NI-0038

N-38 REV. E ENGLISH JUL / 2000

PROPERTY OF PETROBRAS 82 pages

CRITERION FOR DESIGN OF DRAINAGE,SEGREGATION, FLOW AND PRELIMINARY

TREATMENT OF LIQUID EFFLUENTS OFONSHORE INSTALLATIONS

ProcedureThis Standard replaces and cancels the previous revision.This Standard has been totally revised with respect to the previous revision.The Responsible CONTEC Subcommittee provides guidance on theinterpretation of this Standard when questions arise regarding its contents. TheDepartment of PETROBRAS that uses this Standard is fully responsible foradopting and applying the clauses thereof.CONTEC

Comisso de NormasTcnicas

Technical Requirement: a provision established as being the most adequateand which shall be used strictly in accordance with this Standard. If a decision istaken not to follow the requirement (nonconformity to this Standard) it shall bebased on well-founded economic and management reasons, and be approvedand registered by the Department of PETROBRAS that uses this Standard. It ischaracterized by the verb forms shall, it is necessary..., is required to..., itis required that..., is to..., has to..., only ... is permitted, and otherequivalent expressions having an imperative nature.Recommended Practice: a provision that may be adopted under the conditionsof this Standard, but which admits (and draws attention to) the possibility ofthere being a more adequate alternative (not written in this Standard) to theparticular application. The alternative adopted shall be approved and registeredby the Department of PETROBRAS that uses this Standard. It is characterizedby the verbal form should and equivalent expressions such as it isrecommended that... and ought to... (verbs of a nonmandatory nature). It isindicated by the expression: [Recommended Practice].Copies of the registered nonconformity to this Standard that may contribute tothe improvement thereof shall be submitted to the Responsible CONTECSubcommittee.Proposed revisions to this Standard shall be submitted to the ResponsibleCONTEC Subcommittee, indicating the alphanumeric identification and revisionof the Standard, the clause(s) to be revised, the proposed text, andtechnical/economic justification for revision. The proposals are evaluated duringthe work for alteration of this Standard.

SC - 34Environment

The present Standard is exclusive ownership of PETRLEOBRASILEIRO S.A. - PETROBRAS, for internal use in the company,and any reproduction for external use or disclosure, withoutprevious express authorization, will imply an unlawful actpursuant to the relevant legislation through which the applicableresponsibilities shall be imputed. External circulation shall beregulated by a specific clause of Secrecy and Confidentiality,pursuant to the terms of the intellectual and industrial propertylaw.

ForewordPETROBRAS technical standards are prepared by Working Groups - GTs

(consisting of PETROBRAS specialists and specialists from PETROBRAS Subsidiaries), arecommented by Local Representatives (representatives of the Industrial Units, Engineering Projects,Technical Divisions and PETROBRAS Subsidiaries), are approved by the ResponsibleSubcommittees - SCs (consisting of specialists belonging to the same specialty, representing thevarious PETROBRAS Departments and PETROBRAS Subsidiaries), and approved by the CONTECGeneral Assembly (consisting of representatives of the Superintendencies of the PETROBRASDepartments and PETROBRAS Subsidiaries that use PETROBRAS technical standards). APETROBRAS technical standard is subjected to revision at any time by the ResponsibleSubcommittee and must be reviewed every 5 years to be revalidated, revised or cancelled.PETROBRAS technical standards are prepared in accordance with standard PETROBRAS N - 1.For complete information about PETROBRAS standards see PETROBRAS Technical StandardsCatalog.

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SUMARY

FOREWORD............................................................................................................................................................ 8

1 SCOPE ................................................................................................................................................................ 8

2 SUPPLEMENTARY DOCUMENTS ..................................................................................................................... 8

3 DEFINITIONS ...................................................................................................................................................... 9

3.1 EMERGENCY CONTROL WATER ....................................................................................................... 9

3.2 CONTAINED AREA............................................................................................................................... 9

3.3 CONTROLLED AREAS ......................................................................................................................... 9

3.4 ACCUMULATION BOX........................................................................................................................ 10

3.5 TANK BOTTOM DRAINAGE SYSTEM SAMPLING BOX.................................................................... 10

3.6 COLLECTOR TANK OF THE DIVED AREA........................................................................................ 10

3.7 CONTAMINATED COLLECTOR TANK............................................................................................... 10

3.8 TANK BOTTOM DRAINAGE MANEUVERING AND INSPECTION BOX............................................ 10

3.9 PASSAGE BOX ................................................................................................................................... 10

3.10 SPECIAL PASSAGE BOX................................................................................................................. 10

3.11 PASSAGE BOX WITH WATER SEAL............................................................................................... 10

3.12 TANK BOTTOM DRAINAGE SYSTEM OUTLET BOX...................................................................... 10

3.13 VALVES BOX OF THE DIVED AREA................................................................................................ 11

3.14 FLOOR GRATER WITH WATER SEAL ............................................................................................ 11

3.15 CLOSED SYSTEM ............................................................................................................................ 11

3.16 SEALED SYSTEM............................................................................................................................. 11

3.17 DRY-WEATHER FLOW RATE .......................................................................................................... 11

4 GENERAL CONDITIONS .................................................................................................................................. 11

5 SYSTEMS CLASSIFICATION............................................................................................................................ 12

6 CLEAN PLUVIAL SYSTEM................................................................................................................................ 13

6.1 DESCRIPTION .................................................................................................................................... 13

6.2 MAJOR CONTRIBUTIONS.................................................................................................................. 13

6.3 DRAINAGE, COLLECTION AND FLOW ............................................................................................. 13

6.4 PRELIMINARY TREATMENT.............................................................................................................. 13

7 CONTAMINATED SYSTEM............................................................................................................................... 14

7.1 DESCRIPTION .................................................................................................................................... 14




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8 OILY SYSTEM ................................................................................................................................................... 17

8.1 DESCRIPTION .................................................................................................................................... 17



8.3.1 DRAINAGE OF TANK BOTTOM OILY WATER (SEE FIGURES A-17 TO A-21 OF ANNEX A). 188.3.2 COLLECTION AND FLOW ......................................................................................................... 19


9 SOUR WATER SYSTEM ................................................................................................................................... 21

9.1 DESCRIPTION .................................................................................................................................... 21


9.3 COLLECTION AND FLOW .................................................................................................................. 21


10 CAUSTIC OR ACID SYSTEM.......................................................................................................................... 22

10.1 DESCRIPTION .................................................................................................................................. 22

10.2 MAJOR CONTRIBUTIONS................................................................................................................ 22

10.3 DRAINAGE, COLLECTION AND FLOW ........................................................................................... 23

10.4 PRELIMINARY TREATMENT............................................................................................................ 23

11 SULFIDE SPENT SODA SYSTEM ................................................................................................................. 24

11.1 DESCRIPTION .................................................................................................................................. 24


11.3 COLLECTION AND FLOW ................................................................................................................ 24


12 PHENOLIC SPENT SODA SYSTEM............................................................................................................... 25

12.1 DESCRIPTION .................................................................................................................................. 25




13 PUMP OUT SYSTEM ...................................................................................................................................... 27

13.1 DESCRIPTION .................................................................................................................................. 27


14 HIGH SOLID CONTENT STREAM .................................................................................................................. 27

14.1 DESCRIPTION .................................................................................................................................. 27


14.3 DRAINAGE, COLLECTION AND FLOW ........................................................................................... 28


15 SANITARY SYSTEM ....................................................................................................................................... 29

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15.1 DESCRIPTION .................................................................................................................................. 29




16 SHIP BALLAST OILY WATER SYSTEM ......................................................................................................... 29

16.1 DESCRIPTION .................................................................................................................................. 29

16.2 FLOW ................................................................................................................................................ 29


17 DRILLING DISCHARGE WITH WATER BASE FLUID .................................................................................... 30

17.1 DESCRIPTION .................................................................................................................................. 30



17.4 CONSTRUCTION OF DIKES ............................................................................................................ 30


18 DRILLING DISCHARGE WITH OIL BASE FLUID ........................................................................................... 31

18.1 DESCRIPTION .................................................................................................................................. 31




19 DRILLING CONTAMINATED EFFLUENT ....................................................................................................... 31

19.1 DESCRIPTION .................................................................................................................................. 31



20 COMPLETION EFFLUENTS............................................................................................................................ 32

20.1 DESCRIPTION .................................................................................................................................. 32




21 SPECIAL SYSTEMS........................................................................................................................................ 33

21.1 DESCRIPTION .................................................................................................................................. 33

21.2 SYSTEM FOR EFFLUENTS WHICH CAN BE CONTAMINATED WITH TETRAETHYL LEAD (TEL)OF ETHYLATION UNITS ................................................................................................................ 33

21.2.1 COLLECTION AND FLOW ....................................................................................................... 34

21.2.2 PRELIMINARY TREATMENT ................................................................................................... 34

21.3 EFFLUENTS CONTAMINATED WITH ALCOHOL/MTBE ................................................................. 34



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21.4 EFFLUENTS OF AREAS FOR STORAGE OF SOLID MATERIALS, MATERIALS IN GRAINS ORMATERIALS IN POWDER FORM................................................................................................... 35

21.4.1 DESCRIPTION.......................................................................................................................... 35



21.4.4 PARTITION BOX OR WEIR ONLY ........................................................................................... 36

21.4.5 ACCUMULATION BASIN.......................................................................................................... 36

21.4.6 DECANTING INSTALLATION................................................................................................... 36

21.5 LABORATORY EFFLUENTS............................................................................................................. 36

21.5.1 DESCRIPTION.......................................................................................................................... 36


21.5.3 PRELIMINARY TREATMENT OF TOXIC LABORATORY EFFLUENTS .................................. 37

22 BASIC DESIGN REQUIREMENTS.................................................................................................................. 37

22.1 ROUTING STUDIES.......................................................................................................................... 37

22.2 DIMENSIONING ................................................................................................................................ 38

22.3 SLOPE AND SPEED ......................................................................................................................... 39

22.3.1 SPEED LIMITS.......................................................................................................................... 39

22.3.2 SLOPE LIMITS.......................................................................................................................... 39

22.4 DRAINAGE ELEMENTS AND DEVICES CHARACTERISTICS........................................................ 39

22.4.1 GENERAL................................................................................................................................. 39

22.4.2 CLEAN PLUVIAL SYSTEM....................................................................................................... 40

22.4.3 OILY SYSTEM .......................................................................................................................... 41

22.5 MATERIALS ...................................................................................................................................... 41

22.6 OPERATION MANUAL...................................................................................................................... 42

23 CHARACTERIZATION AND TREATABILITY OF EFFLUENTS ...................................................................... 44

23.1 CHARACTERIZATION OF EFFLUENTS........................................................................................... 44

23.2 TREATABILITY OF EFFLUENTS...................................................................................................... 44

24 TREATMENT AND FINAL DISPOSAL............................................................................................................. 44

FIGURES

FIGURE 1 - DIAGRAM OF EFFLUENTS ROUTING AND PRELIMINARY TREATMENT FROM THECONTAMINATED SYSTEM ............................................................................................................ 15

FIGURE 2 - DIAGRAM OF ROUTING AND PRELIMINARY TREATMENT OF THE OILY SYSTEMEFFLUENTS.................................................................................................................................... 20

FIGURE 3 - DIAGRAM OF ROUTING AND PRELIMINARY TREATMENT OF THE SOUR WATER SYSTEMEFFLUENTS.................................................................................................................................... 22

FIGURE 4 - DIAGRAM OF ROUTING AND PRELIMINARY TREATMENT OF THE HYDROGEN SULFIDESPENT SODA SYSTEM EFFLUENTS............................................................................................ 24

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FIGURE 5 - DIAGRAM OF ROUTING AND PRELIMINARY TREATMENT OF THE PHENOLIC SPENT SODASYSTEM EFFLUENTS.................................................................................................................... 26

FIGURE 6 - DIAGRAM OF ROUTING AND PRELIMINARY TREATMENT OF STREAMS WITH HIGHCONTENT OF SOLIDS ................................................................................................................... 28

FIGURE 7 - DIAGRAM OF ROUTING AND PRELIMINARY TREATMENT OF COMPLETION EFFLUENTSYSTEM.......................................................................................................................................... 33

FIGURE 8 - SPECIAL SYSTEM FOR EFFLUENTS CONTAMINATED WITH ALCOHOL/MTBE....................... 35

FIGURE 9 - DIAGRAM OF ROUTING AND PRELIMINARY TREATMENT OF EFFLUENTS FROM THE AREASFOR STORAGE OF SOLID MATERIALS IN GRAINS OR POWDER FORM ................................. 36

FIGURE 10 - HYDRAULYC DIMENSIONING TABLE........................................................................................... 38

FIGURE A-1 - TYPICAL STREET OUTLINE DRAWING....................................................................................... 45

FIGURE A-2 - TYPICAL OUTLINE DRAWING FOR STREETS DRAINAGE ........................................................ 46

FIGURE A-3 - TYPICAL OUTLINES FOR STREETS AND SLOPES DRAINAGE................................................. 47

FIGURE A-4 - DETAIL 1 ........................................................................................................................................ 48

FIGURE A-5 - DETAIL 2 ........................................................................................................................................ 48

FIGURE A-6 - DETAIL 3 ........................................................................................................................................ 49

FIGURE A-7 - DETAIL 4 ........................................................................................................................................ 49

FIGURE A-8 - DETAIL 5 ........................................................................................................................................ 50

FIGURE A-9 - DIVED AREA DRAINAGE DIAGRAM (FOR CONTAMINATED SYSTEM ONLY).......................... 51

FIGURE A-10 - DIVED AREA DRAINAGE DIAGRAM (WITH ALTERNATIVE TRANSFER TO CLEAN PLUVIALSYSTEM)...................................................................................................................................... 52

FIGURE A-11 - DIVED AREAS DRAINAGE FOR THE CONTAMINATED SYSTEM ONLY ................................. 53

FIGURE A-12 - DRAINAGE OF THE DIVED AREAS (WITH ALTERNATIVE TRANSFER TO CLEAN PLUVIALWATER SYSTEM)........................................................................................................................ 54

FIGURE A-13 - DIVED AREA DRAINAGE (VALVE BOX CLOSE TO DRAINAGE CHANNEL) ............................ 55

FIGURE A-14 - DIVED AREAS DRAINAGE (VALVE BOX FAR FROM THE DRAINAGE CHANNEL) ................. 55

FIGURE A-15 - DIVED AREA DRAINAGE VALVE BOX .................................................................................... 56

FIGURE A-16 - COLLECTOR TANK OF THE DIVED AREA................................................................................. 56

FIGURE A-17 - DIAGRAM SHOWING MANUAL TANK BOTTOM DRAINAGE SYSTEM OPENED SYSTEM(WITH INSPECTION AND MANEUVERING BOXES) .................................................................. 57

FIGURE A-18 - DIAGRAM SHOWING MANUAL TANK BOTTOM DRAINAGE SYSTEM - CLOSED SYSTEM(WITH SAMPLERS)...................................................................................................................... 58

FIGURE A-19 - DIAGRAM SHOWING MANUAL TANK BOTTOM DRAINAGE SYSTEM CLOSED SYSTEM(WITH CENTERED SAMPLERS) ................................................................................................. 59

FIGURE A-20 - DIAGRAM SHOWING AUTOMATIC TANK BOTTOM DRAINAGE SYSTEM (WITH ANOIL/WATER INTERFACE CONTROL SYSTEM FOR EACH TANK)............................................ 60

FIGURE A-21 - DIAGRAM SHOWING AUTOMATIC TANK BOTTOM DRAINAGE SYSTEM (WITH ANOIL/WATER INTERFACE CONTROL SYSTEM FOR A GROUP OF TANKS)............................. 61

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FIGURE A-22 - MODEL OF PARTITION BOX OF CONTAMINATED SYSTEM (WITH OVERFLOW TO THEBAC) ............................................................................................................................................. 62

FIGURE A-23 - MODELS OF OILY SYSTEM PARTITION BOX AND ACCUMULATION BASIN (BAO)............... 63

FIGURE A-24 - CONTAMINATED WATER ACCUMULATION TANK (CAT)......................................................... 64

FIGURE A-25 - OILY WATER ACCUMULATION TANK (OAT)............................................................................. 65

FIGURE A-26 - TYPICAL DIAGRAM OF CONTAINED AREAS ............................................................................ 66

FIGURE A-27 - SIMPLIFIED DIAGRAM OF DRAINAGE SYSTEMS OF A PROCESS UNIT ............................... 67

FIGURE A-28 - DRAINAGE OF CONTAINED AREAS OF PUMPS ...................................................................... 68

FIGURE A-29 - SIMPLE FLOOR GRATER ........................................................................................................... 69

FIGURE A-30 - GRATER FOR EQUIPMENT WITH VISIBLE DISCHARGE ......................................................... 70

FIGURE A-31 - GRATER FOR EQUIPMENT WITH END FLANGED AT THE COUPLING .................................. 71

FIGURE A-32 - FLOOR GRATER WITH WATER SEAL ....................................................................................... 72

FIGURE A-33 - DRAINAGE OF EQUIPMENT....................................................................................................... 73

FIGURE A-34 - OPTIONAL ACCESS FOR DRAINS CLEANING.......................................................................... 74

FIGURE A-35 - GRATER BOX WITH COVER FOR PLUVIAL WATERS.............................................................. 75

FIGURE A-36 - CONTAMINATED COLLECTOR TANK........................................................................................ 76

FIGURE A-37 - PASSAGE BOX WITH WATER SEAL FOR INLET PIPING SYSTEM WITH ND 50 CM .......... 77

FIGURE A-38 - PASSAGE BOX WITH WATER SEAL FOR INLET PIPING SYSTEM WITH ND > 50 CM........... 78

FIGURE A-39 - SQUARE PASSAGE BOX WITHOUT NECK ............................................................................... 79

FIGURE A-40 - SQUARE PASSAGE BOX WITH NECK....................................................................................... 80

FIGURE A-41 - COLLECTOR TANK WITH PUMPING.......................................................................................... 81

FIGURE A-42 - TYPICAL DIAGRAM FOR DRAINAGE CHANNELS OF PUMP-OUT SYSTEM - PLAN VIEW ANDSECTION...................................................................................................................................... 82

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/FOREWORD

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FOREWORD

This Standard is the English version (issued in JAN/2001) of Standard PETROBRAS N-38 -REV. E - JUL/2000.

1 SCOPE

1.1 This Standard establishes basic criteria and requirements of design which shall beconsidered for the following systems: drainage, collection, segregation, routing, accumulationand preliminary treatment of industrial and domestic liquid effluents of PETROBRASOnshore Units.

1.2 This Standard is applied to design starting from its issue date.

1.3 This Standard contains Technical Requirements and Recommended Practices.

2 SUPPLEMENTARY DOCUMENTS

The documents listed below contain valid requirements for the present Standard.

Resoluo CONAMA-020/86, de 18/06/86;PETROBRAS N-1203 - Design for Fire Protection Systems in Hydrocarbon

Installations;PETROBRAS N-1601 - Construo de Drenagem e de Despejos Lquidos em

Unidades Industriais;PETROBRAS N-1645 - Critrios de Segurana para Projeto de Instalaes

Fixas de Armazenamento de Gs Liqefeito dePetrleo;

PETROBRAS N-1674 - Layout Design for Petroleum Refinery;PETROBRAS N-1886 - Projeto de Sistemas de Combate a Incndio com gua

e Espuma para reas de Armazenamento eTransferncia de lcool;

PETROBRAS N-1947 - Aplicaes de Revestimento Base de Esmalte deAsfalto em Tubulaes Enterradas ou Submersas;

PETROBRAS N-2238 - Revestimentos de Dutos Enterrados com FitasPlsticas de Polietileno;

ABNT NBR 5645 - Tubo Cermico para Canalizaes;ABNT NBR 5688 - Sistemas Prediais de gua Pluvial, Esgoto Sanitrio e

Ventilao - Tubos e Conexes de PVC, Tipo DN -Requisitos;

ABNT NBR 7229 - Projeto, Construo e Operao de Sistemas deTanques Spticos;

ABNT NBR 7362-1 - Sistemas Enterrados para Conduo de Esgoto -Parte 1: Requisitos para Tubos de PVC com JuntaElstica;

ABNT NBR 7661 - Tubo de Ferro Fundido Centrifugado, de Ponta eBolsa, para Lquidos sob Presso, com Junta NoElstica;

ABNT NBR 7663 - Tubo de Ferro Fundido Dctil Centrifugado, paraCanalizaes sob Presso;

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ABNT NBR 7665 - Sistemas para Aduo e Distribuio de gua - Tubosde PVC 12 DEFOFO com Junta Elstica - Requisitos;

ABNT NBR 8160 - Sistemas Prediais de Esgoto Sanitrio - Projeto eExecuo;

ABNT NBR 8682 - Revestimento de Argamassa de Cimento em Tubos deFerro Fundido Dctil;

ABNT NBR 8890 - Tubo de Concreto Armado, de Seo Circular, paraEsgoto Sanitrio;

ABNT NBR 9793 - Tubo de Concreto Simples de Seo Circular paraguas Pluviais;

ABNT NBR 9794 - Tubo de Concreto Armado de Seo Circular paraguas Pluviais;

ABNT NBR 9800 - Critrios para Lanamento de Efluentes LquidosIndustriais no Sistema Coletor Pblico de EsgotoSanitrio;

ABNT NBR 9896 - Glossrio de Poluio das guas;ABNT NBR 10004 - Resduos Slidos;ABNT NBR 10158 - Tampo Circular de Ferro Fundido - Dimenses;ABNT NBR 10160 - Tampo Circular de Ferro Fundido;ABNT NBR 10843 - Tubos de PVC Rgido para Instalaes Prediais de

guas Pluviais;ABNT NBR 10845 - Tubo de Polister Reforado com Fibras de Vidro, com

Junta Elstica, para Esgotos Sanitrios;ABNT NBR 11852 - Caixa de Descarga;Associao Brasileira de Cimento Portland - BT 55 - Efeito de Vrias SubstnciasSobre o Concreto;PFAFSTETTER, Otto - Chuvas Intensas no Brasil - 2 Edio - 1982 - RJ -

Departamento Nacional de Obras de Saneamento.

3 DEFINITIONS

For the purposes of this Standard the definitions in items 3.1 to 3.17 are adopted,complemented by those given in standard PETROBRAS N-1674 and standardsABNT NBR 7229 and NBR 8160.

3.1 Emergency Control Water

Water used on special occasions such as for fire fighting, for cooling vessels or equipmentunder abnormal conditions and for dilution of toxic, combustible or flammable liquids, gasesor vapors.

3.2 Contained Area

An area surrounded by walls, projections, drainage channels, or lowered to limit thespreading of liquids inside it and to promote their flow through graters, to prevent thereception of contributions from outside the contained area (see FIGURE A-6 of ANNEX A).

3.3 Controlled Areas

Contained areas which have devices for controlling the effluents flow received therein, suchas dived area.

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3.4 Accumulation Box

A box to storage oily waters from the tank bottom.

3.5 Tank Bottom Drainage System Sampling Box

A box to collect the samplers flow of storage tank bottom drainage piping system, built with aneck to prevent the inflow of pluvial waters accumulated in the basin (see FIGURES A-18and A-19 of ANNEX A).

3.6 Collector Tank of the Dived Area

A box to collect pluvial waters from inside the basin, with a device for removing solids,interconnected through pipe to the basin valve box (see FIGURES A-9, A-10, A-11, A-12 andA-16 of ANNEX A).

3.7 Contaminated Collector Tank

A box to collect pluvial waters or emergency control waters from non-contained areas ofprocess units and the drainage from other boxes and sending them to a contaminatedsystem with a water seal device and a metal grater (see FIGURE A-36 of ANNEX A).

3.8 Tank Bottom Drainage Maneuvering and Inspection Box

A box for incoming pipe from the storage tank bottom drain, to permit the visualization of thedrained fluid. It is located near the storage tank and it has a neck to prevent the inflow ofbasin pluvial waters (see FIGURE A-17 of ANNEX A).

3.9 Passage Box

A box to collect and/or rout flows, allowing the inspection and cleanup of drainage networks,which may be fitted with a vent device (see FIGURES A-39 and A-40 of ANNEX A).

3.10 Special Passage Box

A passage box to collect and/or rout flows, allowing the inspection and cleanup of specificdrainage networks such as sour waters system and spent soda system among others. Theseboxes shall have suitable characteristics for each system.

3.11 Passage Box with Water Seal

A passage box with a water seal and vent device to prevent the propagation of gases alongthe pipe (see FIGURES A-37 and A-38 of ANNEX A).

3.12 Tank Bottom Drainage System Outlet Box

A box to access to the tank bottom drainage pipe outlet valve, with a spindle to hand at theground level and located outside the basin (see FIGURES A-17, A-18 and A-19 ofANNEX A).

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3.13 Valves Box of the Dived Area

A box to access to the valve or to the manifold of the basin drainage outlet valve, locatedoutside the basin, with spindles for handling at the ground level, interconnected to thecollector tank, which allows the pluvial waters in the basin to be sent to the clean orcontaminated pluvial system (see FIGURES A-9, A-10, A-11, A-12, A-13, A-14 and A-15 ofANNEX A).

3.14 Floor Grater with Water Seal

A grater to collect pluvial water or emergency control water in the contained areas and tosend the effluents to the passage box (see FIGURE A-32 of ANNEX A).

3.15 Closed System

A group of pipes, boxes and other devices to prevent the direct contact of the liquid streamscirculating inside them in contact with the atmosphere.

3.16 Sealed System

A group of pipes, boxes and other devices to prevent vapors release to the atmosphere,relieving them through specific accessories.

3.17 Dry-Weather Flow Rate

Consists on flows rate which do not depend on rains, such as drainage from the bottom ofpetroleum and its products tanks, drainage from equipment, purge from cooling towers,different effluents from process units and floor washing waters of all areas characterized bythe presence of various contaminating agents.

4 GENERAL CONDITIONS

4.1 The philosophy which shall orient the execution of draining designs shall be thecomplete segregation of oily/contaminated systems from the clean pluvial system, to preventthe discharge of oily/contaminated waters into the receiving body and overload of the EffluentTreatment Station with the improper outflow of clean pluvial waters.

4.2 Drainage systems shall be dimensioned to hold the highest of the following contributingflows rates:

a) rain, emergency discharges, drains of equipment, machines cooling water andprocess effluents, occurring simultaneously;

b) emergency control waters.

4.3 For any system, the contribution of pluvial water shall be calculated considering thearrival time of the contribution located farthest away until the interest point (concentrationperiod), besides the rain intensity variation with time.

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4.4 The volume of pluvial waters for any system shall be calculated considering the soilabsorption coefficient.

4.5 The region rainfall shall be considered for a period of 20 years. These data shall beobtained through local records gathered by an entity of proven capacity or rates indicated inthe book Chuvas Intensas no Brasil, by Otto Pfafstetter.

4.6 The flows rate indicated by standards PETROBRAS N-1203 and N-1886 shall beconsidered as total contribution of emergency control water. For design purposes, anemergency situation occurring in more than one unit simultaneously shall not be considered.

4.7 The equipment such as furnaces, pumps, heat exchangers and others which make thearea susceptible to leakage of petroleum, its products, excluding LPG and other liquefiedgases, and/or other chemical products, shall be installed in contained areas (seeFIGURE A-26 of ANNEX A).

4.8 The piping system accessories located on pipeways, such as valves, flanges, vents,drains, filters and other places where leakage of petroleum, its products and/or otherchemical products, excluding LPG and other liquefied gases, may occur, shall be installed incontained areas.

4.9 The Operation Manual of systems which contribute to the drainage system should bechecked and, if necessary, revised, so that the contaminant contents and flows rate of liquideffluents from the process units be minimized by adjustments in the process, recycling and/ortreatment at the location. [Recommended Practice]

5 SYSTEMS CLASSIFICATION

Liquid effluents shall be classified into one of the following systems:

a) clean pluvial;b) contaminated;c) oily;d) sour waters;e) caustic or acid;f) sulfide spent soda;g) phenolic spent soda;h) pump-out;i) high solid content stream;j) sanitary;k) ship ballast oily water;l) drilling discharge with water base fluid;m)drilling discharge with oil base fluid;n) contaminated drilling;o) completion effluents;p) specials [Tetraethyl Lead (TEL), MTBE, alcohol, areas used for storage of solid

materials, laboratories].

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6 CLEAN PLUVIAL SYSTEM

6.1 Description

A system to which uncontaminated water streams are sent, permitting the presence ofsubstances in such concentrations that they can be directly discharged into the receivingbody, in accordance with CONAMA Resolution 020/86 and/or the applicable State orMunicipal Legislation.

6.2 Major Contributions

6.2.1 Pluvial water, emergency control water and floor washing water collected at pointssuch as:

a) administrative area;b) streets outside the battery limits of the units;c) buildings, streets and areas not subject to contamination by process units,

transfer and storage areas and utilities stations;d) areas for spheres and cylinders of gases, including liquefied gases, as well as

the respective escape channels and contention basins;e) dived areas containing LPG or other refrigerated gases;f) dived areas with a segregated tank bottom drainage system (see item 7.3.1);g) pipeways, excluding their contained areas;h) earthmovement areas intended for future expansions.

6.2.2 Effluents such as: purge from boilers.

6.3 Drainage, Collection and Flow

6.3.1 The dived area shall be drained as described in item 7.3.1.

6.3.2 In the case of the area for spheres and cylinders of gases, the effluent shall be sent toa contention basin, in accordance with standard PETROBRAS N-1645, before beingreleased into the clean pluvial system.

6.3.3 A gravity flow in an opened drainage channel should preferably be adopted. Thedrainage channel may be built of reinforced concrete, masonry covered with mortar, concretehalf-round, or molded in the soil covered with reinforced mortar.

6.4 Preliminary Treatment

The effluents characterized in this system shall undergo treatments for removal of coarsesolids and sand before being released into the receiving body. The streams that receivecontribution from drainage from the dived areas shall have a sealed baffle with a water seal.

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7 CONTAMINATED SYSTEM

7.1 Description

A system to which water streams characterized by the occasional presence of hydrocarbonsare sent, and which may contain suspended and dissolved solids and/or other contaminantsin such concentrations that they cannot be released directly into the receiving body, inaccordance with CONAMA Resolution 020/86 and/or the applicable State or MunicipalLegislation.


7.2.1 Pluvial water, emergency control water, cooling water, floor washing water anddrainage collected at places such as:

a) dived areas, including those which have a segregated tank bottom drainagesystem (see item 7.3.1), excluding those which containing LPG and otherliquefied or refrigerated gases;

b) contained areas of pipeways, that is, areas susceptible to leakage such asthose near vents, flanges, valves, drains and other accessories;

c) manifold areas;d) non-contained areas of process units, of thermoelectric power stations and of

pumps;e) contained areas of Liquid Effluents Treatment Station;f) contained areas of compressor stations;g) area of oil base drilling and/or completion fluid treatment station;h) areas for collection and cleanup of materials and equipment to avoid oil

pollution;i) area for checking loads tank trucks.

7.2.2 Effluents such as: continuous purge from accumulation basins of cooling towers.


7.3.1 Drainage of the dived area (see FIGURES A-9 to A-16 of ANNEX A).

7.3.1.1 The drainage from the dived area shall be completely segregated from the drainagefrom tank bottoms.

7.3.1.2 Pluvial waters that fall in the dived areas shall be sent to the collector tanks of thedived area.

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7.3.1.3 The outlet pipe of the collector tank, after passing through the dike, shall be sent tothe basin valve box, which sends the flow to the contaminated system (see FIGURES A-9and A-11 of ANNEX A). As an alternative to this system, a manifold may be installed in thebasin valve box so as to permit the flow to be sent to the clean or contaminated pluvialsystem (see FIGURES A-10 and A-12 of ANNEX A), provided the following conditions arefollowed:

a) the tank to be drained shall have a telemetry-based level measuring system;b) existence of operational criteria ensuring that the basin drainage operation and

transfer of products to the tank operation will not occur simultaneously;c) existence of instrumentation and control systems or operational procedures

ensuring constant supervision of the basin or valve box, so as to guarantee theabsence of oil in the clean pluvial system.

7.3.2 A gravity flow shall be adopted, preferably using open reinforced concrete drainagechannels toward the Liquid Effluent Treatment Station. The pumping to a nearby collectorshall only be adopted in exceptional cases and preferably outside the battery limits of theunits.

7.3.3 The use of piping system shall be adopted within the battery limits of process units atstreet crossings or where necessary.

7.3.4 Collection and flow of effluents from non-contained areas of process units, ofthermoelectric power stations, of pump stations, as well as pipeways located within theseareas shall be accomplished through a sealed and buried system up to the battery limit of theunit.


7.4.1 The diagram shown in FIGURE 1 shall be adopted as a basis for the preliminarytreatment:

FIGURE 1- DIAGRAM OF EFFLUENTS ROUTING AND PRELIMINARYTREATMENT FROM THE CONTAMINATED SYSTEM

Disposal inReceiving Body

ContaminatedEffluent

DesandingUnitGrating

PartitionBox

AccumulationBasin or Tank ofContaminated

System

PrimaryTreatment

1st Weir

2nd Weir

Overflow Unit ofAccumulation

Basin or Tank ofOily System

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7.4.2 Under dry weather conditions, the effluents shall be sent to the SAO without free fall ofeffluent. Under rain or fire conditions, when the inflow rate into the partition box is higher thanthe maximum transfer capacity of this system to the SAO, the excess flow rate shall bediverted through the weir to the accumulation basin.

7.4.3 Grating

Equipment used for retaining coarse solids through fixed or movable gratings with facilitiesfor cleaning and removing retained solids.

7.4.4 Desanding Unit

Equipment used for removing fine solids, consisting of a settling system, equipped withfacilities for cleaning and removing retained solids.

7.4.5 Partition Box (See FIGURE A-22 of ANNEX A)A box for ruting excess flows resulting from rain or emergency water, when the inflow rateinto this box is over than the maximum transfer capacity allowed for this system to thetreatment station. Under normal conditions, the effluent is sent to the treatment stationthrough a suitable flow rate limiting system. This box has two weirs: the first one for divertingthe excess flow to the BAC/CAT and the second, fitted with a baffle and a water seal, is usedfor diverting the flow exceeding the capacity of the BAC/CAT to the receiving body.

7.4.6 Accumulation Basin or Tank - BAC/CAT (See FIGURES A-22 and A-24 of ANNEX A)

7.4.6.1 Reinforced concrete basin or closed tank dimensioned to store the effluent flow ratefrom the contaminated system exceeding the treatment station capacity. After the rain oremergency situation has finished, the accumulated effluent shall be transferred to thetreatment station, preferably by gravity, with a flow rate not exceeding the maximum designflow rate specified for the treatment system.

7.4.6.2 The BAC/CAT capacity shall be dimensioned to hold the largest of the followingvolumes:

a) emergency control water for 30 minutes of fire fighting, with the flow rateaccording to the criterion of standards PETROBRAS N-1203 and N-1886;

b) the excess flow rate defined in item 7.4.2, calculated for the maximum regionrainfall, determined in a recurrence period of 20 years, and for a rain durationequal to the period of time needed for the arrival contribution located farthestaway at the basin, plus 10 minutes.

7.4.6.3 When the contaminated flow rate exceeding the capacity of the treatment stationaccumulates in a tank (CAT), the following premises shall be followed (see FIGURE A-24 ofANNEX A):

a) the tank shall be built in accordance with the API Manual design criteria;b) the maximum working level of the CAT shall be below the maximum level of the

contaminated partition box, providing a difference in level to promote the flowmovement;

c) provision shall be made for an emergency overflow over the maximum workinglevel of the CAT.

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7.4.6.4 More than one group may be used (partition box plus BAC/CAT), to reduce theperiod of time needed for arrival of the contribution located farthest away.

8 OILY SYSTEM

8.1 Description

A system to which water streams characterized by the constant presence of hydrocarbonsare sent, and which may contain suspended and dissolved solids and/or other contaminants.


8.2.1 Pluvial water, emergency control water, cooling water, floor washing water anddrainage collected at places such as:

a) contained areas of process units, of thermoelectric power stations and ofpumps;

b) loading and unloading areas of trucks and tank cars for petroleum or itsproducts;

c) area for washing equipment in factory;d) area for washing heat exchanger bundles;e) contained areas of the fire fighting training field;f) landfarming;g) service stations and garages where lubrication and washing of vehicles occur.

8.2.2 Effluents such as:

a) drainage from the bottom of tanks containing petroleum and its products,excluding LPG and other liquefied or refrigerated gases;

b) drainage from the bottom of slop tanks, when not contaminated by thecompounds indicated in item 9.1 (see Note);

c) drainage from the bottom of industrial embankment;d) drainage from the bottom of equipment of process units, of thermoelectric

power stations and of areas of pumps containing or moving oils, including thosefrom sour water and spent soda treatment units;

e) intermittent purge of surfaces of accumulation basins of cooling towers;f) effluents from desalters;g) petroleum products water;h) tank ballast oily water;i) effluents from tanks for washing parts, equipment and instruments which use

petroleum products and other chemical products.

Note: The slop tanks containing effluents presenting contamination by the compoundsmentioned above shall be fitted with devices allowing the drainage to a sour watersystem.

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8.3.1 Drainage of Tank Bottom Oily Water (See FIGURES A-17 to A-21 of ANNEX A)

8.3.1.1 Basic Concepts

a) the drainage of oily waters from tank bottom should preferably be automatic,with gravity flow to the oily system;

b) at the outlet of the dived area, the drainage pipe shall be fitted with valves witha spindle for handling at ground level, centered at the outlet box;

c) the tank bottom drainage shall be always kept separate from drainage frompluvial waters falling in the dived areas;

d) the automatic or manual drainage system shall have resources for recoveringthe volume of oil retained in the lines between the tank and the block valves;

e) the automatic or manual drainage system shall have a water/oil interfacedetection system;

f) the drain valves shall be kept close to the tank shell regardless of the solutionadopted;

g) in the case that is necessary control the tank bottom drainage flows rate fortreatment, a drainage tank may be used;

h) if a suitable treatment system is unavailable, the tank bottom drainage shall besent to an accumulation box for future treatment.

8.3.1.2 Automatic Tank Bottom Drainage System (See FIGURES A-20 and A-21 ofANNEX A)

a) this system shall be basically comprised of motor-operated block valves (onevalve for each tank), water/oil interface sensing elements and a programmablelogic controller (PLC);

b) in the case of the solution adopted is a dedicated PLC, exclusively for theautomatic drainage system, it shall be capable of communicating with the PLCof the plant;

c) oily waters shall flow through piping system, by gravity, directly from the tanksto the oily system;

d) sensing elements shall detect the content of oil in the drained fluid;e) these elements shall send signals to the programmable logic controller which

controls the flow block valves installed in the drainage lines of the tanks;f) a water/oil interface control system shall be installed, preferably as close as

possible to each tank;g) if a water/oil interface control system is adopted for each group of tanks

connected to a block valve manifold, the sensing element shall be located tominimize its distance from the storage tanks, with provision being made for arecovery system of the product contained in the piping system section betweenthe tank and the block valve.

8.3.1.3 Manual Tank Bottom Drainage System

a) opened system (see FIGURE A-17 of ANNEX A):- the tank bottom drain shall discharge into an inspection and maneuvering box,

built inside the basin, with a neck to prevent the pluvial waters inflow, allowingthe visualization of the water/oil interface;

- according to the operational needs or the characteristics of each tank, theremay be one or more boxes per tank built near each drain;

- from the inspection and maneuvering box the flow is sent through pipingsystem to the outlet box;

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b) closed system (see FIGURES A-18 and A-19 of ANNEX A):- the tank bottom drainage piping system shall have a sampler located near the

next drain, allowing visual detection of the water/oil interface;- there shall be a sampling box with a neck below the sampler to prevent the

pluvial waters inflow from the basin;- there may be one or more drainage points according to the operational needs

or characteristics of each tank, with the samplers located near each tankdrain;

- the drainage from the sampling box shall be sent to the oily water pipingsystem;

- in the case of the samplers and all valves are centered for ease of systemoperation, a system shall be provided for recovery the oil retained in the lines,through a group of specific lines and valves, which shall discharge into anaccumulation sump tank located outside the basin.

8.3.1.4 Drainage System Using Drainage Tank

a) the individual drainages from tanks shall be interconnected to a header whichwill send the flow to the drainage tank;

b) tank drainage shall stop automatically via a signal indicating the end of thewater phase from the sensor installed at a strategic point or another waterphase indication system, so as to minimize the presence of oil in piping system;

c) the effluents shall be sent from the drainage tank to the oily system, preferablyby gravity, with controlled flow rate;

d) the drainage tank shall have an oil collecting floating device.

8.3.1.5 Drainage System Using Accumulation Box

a) the dimensioning of the accumulation box shall be compatible with the volumeto be drained and with the transfer and treatment capacities;

b) the accumulation box shall be provided with a level control system, interlockedwith the tank drainage system, to prevent the box from overflowing;

c) the accumulation box shall have installations to allow it to be emptied into cartsor into the treatment system.

8.3.2 Collection and Flow

Collection and flow shall always be accomplished through a sealed and buried system. Theflow shall be by gravity toward the Liquid Effluent Treatment Station. The pumping to anearby collector shall only be adopted in exceptional cases.


8.4.1 The diagram shown in FIGURE 2 shall be adopted as a basis for the preliminarytreatment.

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FIGURE 2 - DIAGRAM OF ROUTING AND PRELIMINARY TREATMENT OF THEOILY SYSTEM EFFLUENTS

8.4.2 Under dry weather conditions, the effluents shall be sent to the SAO without free fall ofeffluent (submerged incoming piping system). Under rain or fire conditions, when the inflowrate into the partition box is higher than the maximum transfer capacity of this system to theSAO, excess flow shall be diverted through a weir to the accumulation basin/tank.

8.4.3 Landfarming and other areas effluents that may carry significant quantities of sandshall pass through a local system for removal of these solids before being sent to thepreliminary treatment.

8.4.4 Grating

Equipment for retaining coarse solids through fixed or movable gratings provided withinstallations for cleaning and removing retained solids.

8.4.5 Partition Box (See FIGURE A-23 of ANNEX A)A box for sending oily effluents from the process and pluvial or emergency waters of oilyareas. Under normal conditions the effluent is sent to the treatment station through a suitableflow rate limiting system. When the inflow into this box is higher than the maximum capacityallowed for transfer to the treatment station, the excess flow is diverted through a weir to theBAO/OAT.

8.4.6 Accumulation Basin or Tank - BAO/OAT (See FIGURES A-23 and A-25 of ANNEX A)

8.4.6.1 Reinforced concrete basin or closed tank dimensioned to hold the flow rate of oilyeffluent exceeding the capacity of the treatment station. After the rain or emergency situationhas ceased, the accumulated effluent shall be transferred to the treatment station, preferablyby gravity and without free fall of effluent, with a flow rate not exceeding the maximum designflow rate specified for the treatment system.

OilyEffluent

PrimaryTreatmentGrating PartitionBox

AccumulationBasin/Tank ofOily System

AccumulationBasin/Tank ofContaminated

System

Overflow

Pipe

Weir

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8.4.6.2 The capacity of the basin/tank shall be dimensioned to hold the highest of thefollowing volumes:

a) emergency control water for the periods and flows rate for fire fighting defined instandards PETROBRAS N-1203 and N-1886;

b) the excess flow rate described in item 8.4.2, for the maximum region rainfall,determined in a recurrence period of 20 years and considering a period of2 hours and 30 minutes of rainfall.

8.4.6.3 The BAO shall be fitted with a weir, with a baffle to retain oil, to permit its overflow tothe BAC.

8.4.6.4 When the flow exceeding the capacity of the treatment station is accumulated in thetank (OAT), the following premises shall be observed (see FIGURE A-25 of ANNEX A):

a) the tank shall be built in accordance with the API Manual design criteria;b) the maximum working level of the OAT shall be below the maximum level of the

oily partition box, providing a difference in level to promote movement of flow;c) the overflow level shall be below the maximum level of the oily partition box and

over the maximum level of the BAC/CAT to promote displacement of flows.

9 SOUR WATER SYSTEM

9.1 Description

A system to which steam condensate from the process units and other streamscontaminated especially with sulfides, mercaptides, ammonia, cyanides, phenols, cresolsand other contaminants.

9.2 Major Contributionsa) condensate from the atmospheric distillation reflux drum;b) condensate from the vacuum distillation top drum;c) condensate from the reflux drum of the fractionating column of the Catalytic

Cracking units (FCC or RFCC);d) condensate from the reflux drum of stabilizers of hydrosulfurizations (HSSs)

and hydrotreatments (HDTs);e) water for washing gases of the FCC and RFCC;f) liquid from the flare system condensate separation drum;g) other components similar to those described above from the other units such as

Coke, Reform and others, besides effluents from their reactors and productwashing equipment;

h) drainage from the bottom of slop tanks when contaminated with the compoundsindicated in item 9.1.

9.3 Collection and Flow

Collection and flow shall be accomplished through a closed system. These effluents shall besent to the Sour Water Treatment Unit.

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SourWaters

Storage andPreliminarySeparation

of Oil

Burning orRecoveryof Sulfur

Reuse orOily System

Reuse orOily System

Sour WaterTreatment Unit

Recovered Oil

Residual Gas

Effluent

FIGURE 3 - DIAGRAM OF ROUTING AND PRELIMINARY TREATMENT OF THESOUR WATER SYSTEM EFFLUENTS

9.4.2 Storage and Preliminary Separation of Oil

Sour waters shall be stored in a vessel or load tank capable of allowing the unit to operate ata constant flow rate and with a sufficient volume to contain the inventory of the unit in case ofan emergency. The vessel or tank shall be sealed with inert gas or fuel gas, with relief to theflare system. The system shall have installations for separating oil, with the separated oilbeing sent for re-use or to the oily system and the sour waters sent to the sour watertreatment unit.

9.4.3 Sour Water Treatment Unit

The sour water treatment unit shall separate the gas and liquid phases so as to permit thegas phase to be sent to the residual gas system or to the sulfur recovery system and theliquid phase for re-use, such as desalination of petroleum, or to the oily system. When thedestination of the liquid phase effluent is the oily system, its maximum temperature shall belimited to 40 C. The contents of contaminants, particularly sulfides and ammonia, shall besuch as to ensure that the final effluent of the industrial effluent treatment unit complies therequirements of the applicable environmental legislation.

10 CAUSTIC OR ACID SYSTEM

10.1 Description

A system to which water streams characterized by contamination through drainage, spillageor leakage of equipment which move or contain caustic or acid products.

10.2 Major ContributionsPluvial waters, emergency control waters, cooling waters and floor washing waters collectedat places such as:

a) contained areas of equipment of process units, containing or moving caustic oracid fluids such as proportioning pumps, soda tanks and sulfuric acid tanks;

b) contained areas of units used for preparation of caustic or acid solutions;c) contained areas for loading and unloading caustic or acid fluids.

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10.3.1 The drainages from contained areas, as well as the effluents from operationsinvolving regeneration and displacement of ionic exchange vessels, shall be sent tocontainment/neutralization tank(s).

10.3.2 Collection and flow shall be accomplished at all times through a closed and buriedsystem or covered drainage channels with removable covers, resistant to alkalis and acids.These effluents shall be brought together in a special passage box within the limits of eachunit and then sent, if possible, to a special central passage box for subsequent transfer to thecontainment/neutralization tank.

10.3.3 When the transfer from the central box to the containment tank is done by pumping,the pumping system shall be designed so as to ensure that there will be no possibility ofoverflowing.

10.3.4 The containment/neutralization tank shall be in reinforced concrete, with anti-corrosive coating, and provided with effluent neutralization installations.

10.3.5 The effluents from backwashing and rinsing operations may be sent to the cleanpluvial system, provided they are free of hydrocarbons and substances with concentrationsbelow the limit established by CONAMA Resolution 020/86. [Recommended Practice]

10.3.6 Sulfuric acid and caustic soda tank drains shall be fitted with double blockvalves.


10.4.1 The largest contribution between rain (2 hours and 30 minutes of rainfall) andaccidents shall be considered for the dimensioning of the system. The effluents from thecaustic drainage system shall be sent to a containment/neutralization tank.

10.4.2 Containment/neutralization tank(s) containing acid or alkaline effluents shall be sizedto contain the largest of the following possible effluent volumes:

a) effluent from regeneration and displacement operations;b) largest possible leakage in contained area.

10.4.3 The neutralization of effluent, where necessary, may be effected in the containmenttank, which in this case shall be provided with installations for its accomplishment, or inanother unit which does the neutralization. The containment tank shall have installations forpumped discharge.

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10.4.4 When neutralization is accomplished by the balanced reaction of acid effluents withalkaline effluents, the capacity of the neutralization tank(s) shall be such as to contain theeffluents of regeneration and displacement from a cationic vessel and an anionic vesselcombined together. Neutralization tank(s) shall be covered with alkaline and acid resistantmaterials and equipped with installations to complete the neutralization. After theneutralization, the effluent shall be sent to the clean pluvial water system, provided itcomplies with the requirements of the applicable environmental legislation.

11 SULFIDE SPENT SODA SYSTEM

11.1 Description

System to which water streams characterized by contamination with sulfides, mercaptides,cyanides and phenols in a concentration below 1 % (p/v) are sent. This system also has freenon-reacted soda.

Note: If any stream containing phenols in a quantity over 1 % (p/v), it shall beconsidered phenolic spent soda.

11.2 Major Contributionsa) soda from the caustic treatment of products;b) waters used for washing products from caustic treatments.


Collection and flow shall be effected through a closed system provided with special passageboxes. These effluents shall be sent to the Spent Soda Treatment Unit.


11.4.1 The diagram shown in FIGURE 4 shall be considered as a basis for the preliminarytreatment.

Storage andPreliminary

Separation of OilOily SystemSulfide Spent

Soda

Spent SodaTreatment Unit

Recovered Oil

Effluent

Residual GasBurning orRecoveryof Sulfur

Reuse orOily System

FIGURE 4 - DIAGRAM OF ROUTING AND PRELIMINARY TREATMENT OF THEHYDROGEN SULFIDE SPENT SODA SYSTEM EFFLUENTS

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The effluents from the sulfide spent soda system shall be stored in two tanks or vessels (onereceiving spent soda and the other feeding the unit), which may be the same ones used inthe phenolic spent soda system in case the treatment is the same. The tanks or vessels shallhave installations for removing floating oil, and shall be sealed with inert gas or fuel gas, withrelief to the flare system. The oil separated shall be sent for re-use or to the oily system. Thefeed shall be done in such a manner as to prevent free fall of products in the tank or vessel.

11.4.3 Treatment and Neutralization

11.4.3.1 The sulfide spent soda, free from excessive oil, shall be processed for removal andneutralization of contaminants. Among the existing processes, the following ones areaccepted:

a) saturation with sour acid;b) wet thermal oxidation;c) neutralization with residual flue gases;d) neutralization with strong mineral acid.

11.4.3.2 Regardless of the process adopted, the gases produced in the treatment andneutralization unit shall be sent to the de residual gas system or to the sulfur recovery unit.The oil separated during the process shall be sent for re-use or to the oily system. The liquideffluent from the sulfide spent soda treatment and neutralization unit shall be sent to the oilysystem. Its maximum temperature shall be limited to 40 C, the contents of contaminants,particularly sulfides and phenols and the pH, shall be such as not to impact the effluenttreatment station causing non-compliance of the final effluent with the applicablerequirements.

12 PHENOLIC SPENT SODA SYSTEM

12.1 Description

A system to which water streams contaminated with sulfides, mercaptides, cyanides, cresolsand phenols with a concentration over 1 % (p/v) are sent. This system also has non-reactedfree soda.

12.2 Major Contributionsa) soda from caustic treatments of products;b) waters used for washing products from caustic treatments.


Collection and flow shall be accomplished through a closed system provided with a specialpassage box. These effluents shall be sent to the Spent Soda Treatment Unit with re-use ofthe cresols being possible.

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12.4.1 The diagram shown in FIGURE 5 shall be adopted as a basis for the treatment.

FIGURE 5 - DIAGRAM OF ROUTING AND PRELIMINARY TREATMENT OF THEPHENOLIC SPENT SODA SYSTEM EFFLUENTS


The effluents from the phenolic spent soda system shall be stored in two tanks or vessels(one receiving spent soda and the other feeding the unit), which may be the same ones usedin the sulfide spent soda system in case of the same treatment. The tanks shall haveinstallations for removal of floating oil and shall be sealed with inert gas or fuel gas, with reliefto the flare system. The oil separated shall be sent for re-use or to the oily system. The feedshall be accomplished to prevent free fall of product in the tank or vessel.

12.4.3 Treatment and Neutralization

12.4.3.1 The phenolic spent soda excess oil-free shall be processed for removal andneutralization of contaminants. Among the existing processes the following ones areaccepted:

a) saturation with acid gas;b) neutralization with residual flue gases;c) neutralization with strong mineral acid.

12.4.3.2 Regardless of the process adopted, the gases produced in the treatment andneutralization system shall be sent to the residual gas system or to the sulfur recovery unit.The oil separated during the process shall be sent for re-use or to the oily system. The liquideffluent from the phenolic spent soda treatment and neutralization unit shall be sent to theoily system. Its maximum temperature shall be limited to 40 C, the contents ofcontaminants, particularly sulfides and phenols and the pH shall be such as not to impact theeffluent treatment station and thus entail non-compliance of the final effluent with the relevantrequirements.

Phenolic Spent Soda

Re-use or OilySystem

Burning orRecovery of

Sulfur

Oily SystemStorage and

Preliminary Separationof Oil

Spent SodaTreatment

Unit

Re-use

Residual Gas

Recovered Oil

Oil with fraction

withCresols

of Cresols

System

Effluent

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13 PUMP OUT SYSTEM

13.1 Description

A system to which hydrocarbon streams, either specified or otherwise, from the emptying ofequipment, piping system and samplers during scheduled or emergency shutdowns inprocess units shall be sent.


Collection and flow shall be done in accordance with the process design specifications. If thatdesign specifies a buried collecting network within the process unit, that network shall complythe following requirements:

13.2.1 The collector network shall have a constant camber toward the accumulation tank orvessel.

13.2.2 The collector network shall be contained inside concrete drainage channels, filledwith fine, dry and loose sand and closed with a concrete cover totally enclosed withhydrocarbon resistant mastic so as to prevent the entrance of pluvial water inside thechannel (see FIGURE A-42 of ANNEX A).

13.2.3 At each end of the collector there shall be a blind flange to permit the cleanup in caseof clogging. The access to this flange shall be through a concrete box with a cover made ofthe same material.

13.2.4 The bottom of the drainage channel shall have a camber to the boxes of access tothe flange with a device to prevent entrainment of sand. The bottom of the box for access tothe flange shall be interconnected through a siphon to an oily system box.

13.2.5 If the accumulation vessel or tank is located within the battery limits of the unit and itis buried, it shall be installed inside a concrete basin, filled with fine, dry and loose sand, insuch a manner as to ensure that there will not be an empty space between the vessel andother constructive elements.

14 HIGH SOLID CONTENT STREAM

14.1 Description

System to which non-oily water streams with a high concentration of suspended solids aresent.

14.2 Major ContributionsEffluent such as clarifier purges and backwashing of fresh water filters treatment units.

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14.3.1 Collection and flow shall be done based on the process design specifications.

14.3.2 The flow should preferably be by gravity in an open drainage channel, which may bebuilt in reinforced concrete, masonry covered with mortar, concrete half round, or molded inthe soil and covered with reinforced mortar. Depending on the type of chemical productsfound in the system and their concentrations, it may be necessary to use PVC pipes fordrainage.

14.3.3 A special attention shall be paid to the drainage design so as to prevent low speedthus preventing excessive decanting of solids inside the elements during the flow.



EffluentPartitionBox

Solids Removal

System

Reuse or DisposalIn the Receiving Body

According to theRequirements ofthe Applicable

Environmental Legislation

Water

Treatment orDisposal

Solids

ReceivingBody

Weir(EmergencyOverflow)

FIGURE 6 - DIAGRAM OF ROUTING AND PRELIMINARY TREATMENT OFSTREAMS WITH HIGH CONTENT OF SOLIDS

14.4.2 Under normal process conditions, the effluents shall be sent to the system used forremoving suspended solids and contaminants. The treated water shall subsequently beutilized through recirculation. When it is not possible fully re-use the water after passing itthrough the decanting system, the effluent may be discharged into the receiving body,provided it complies with the requirements of the applicable environmental legislation.

14.4.3 In sporadic and emergency situations, in case of the capacity of the solid removalsystem is exceeded, or in case of process failure, the effluent may be sent to the cleanpluvial system for a short period of time. [Recommended Practice]

14.4.4 The sludge removed during the separation process shall have suitable treatment anddisposal.

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15 SANITARY SYSTEM

15.1 Description

A system to which effluents from the use of water for hygienic purposes are sent.

15.2 Major ContributionsEffluents collected at points such as:

a) lavatories;b) showers;c) closet bowls;d) urinals;e) sinks and drains of kitchen equipment;f) drains of building floors;g) drinking fountains.


15.3.1 Collection and flow shall be done in accordance with standard ABNT NBR 8160.

15.3.2 The non-sanitary effluents shall only be discharged into the sanitary sewage inspecial cases provided the requirements of standard ABNT NBR 9800 are complied.


For units having a secondary (biological) treatment of industrial effluents, the effluents fromthe sanitary system after coarse solids have been removed, shall preferably be sent to thattreatment. In the other cases, the treatment of effluents from the sanitary system shallcomply with standard ABNT NBR 7229, in accordance with the applicable environmentallegislation.

16 SHIP BALLAST OILY WATER SYSTEM

16.1 Description

System to which oily waters from the ballast of ships and other vessels are sent.

Note: The effluents from the ballast of ships that are contaminated with toxic chemicalproducts shall not be included in this system.

16.2 Flow

Oily water from ship ballast shall be flowed of separate piping systems and it shall be sent toballast storage tanks. Ballast storage tanks shall be dimensioned so as to ensure that therewill be no need at any time for ballast oily water to be disposed of without treatment. The flowfrom these tanks to the industrial Liquid Effluent Treatment Station should preferably be bygravity in a closed system.

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The oily water contained in ballast storage tanks shall be sent to the SAO through the oilysystem and then sent to the receiving body, in case of the effluent contamination levelcomplies the requirements of the applicable environmental legislation. Otherwise, the SAOeffluent shall be sent for complementary treatment.

17 DRILLING DISCHARGE WITH WATER BASE FLUID

17.1 Description

Effluents disposed of in drilling dikes without hydrocarbons, and with suspended anddissolved solids and/or other contaminants.


17.2.1 Pluvial waters, floor washing waters from the following areas:

a) drilling fluid tanks;b) drilling platform;c) drilling fluid pumps.


a) discharged water base fluid;b) water used for washing vibrating screens.


Collection and flow shall be by gravity through concrete drainage channels sent to the drillingdike on a selective way so as to prevent the mixture with the clean/sanitary pluvial systems.

17.4 Construction of Dikes

In regions with a very permeable (sandy) soil or in calcareous soils which can containcaverns near the surface (carstic relief) and in the case of residues generated by the drillingfluids belonging to class I or II in accordance with standard ABNT NBR 10004, the drillingdikes shall be waterproofed during their construction by using compacted clay or anothermaterial so as to obtain a maximum vertical permeability coefficient of 10-7 cm/s to preventeffluents percolation and, as a result, contamination of the water table.


The primary treatment is the removal of solids by decanting in drilling dikes and the re-use ofthe contaminated water. At the end of the drilling activity the dike shall be drained and buriedin accordance with the current legislation.

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18 DRILLING DISCHARGE WITH OIL BASE FLUID

18.1 Description

Effluents discharged into drilling dikes with the presence of hydrocarbons, suspended solids,dissolved solids and/or other contaminants.


18.2.1 Pluvial waters, floor washing waters of the following areas:

a) drilling tanks;b) drilling platform;c) drilling pumps.


a) discharged oil base fluid;b) waters for washing vibrating screens.


Collection and flow shall be done by gravity through concrete drainage channels directed to acovered tank or basin to prevent the contamination of the area with oil.


The effluent shall undergo a treatment for removal of coarse solids, sand and fines forreutilization. The unused effluent, which is not re-used, shall undergo treatment for finaldisposal in accordance with the current legislation.

19 DRILLING CONTAMINATED EFFLUENT

It is the effluent likely to contain hydrocarbons and suspended solids.

19.1 Description

These are pluvial waters, waters used for washing and for drainage collected in the areas ofmotors and generators of the rig.


Collection and flow of these effluents shall be by gravity through concrete drainage channelsdirected to a water/oil separator, on a selective way, so as to prevent the mixture amongclean/sanitary/oily pluvial systems.

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The primary treatment is the removal of oil in the water/oil separator and the drainage ofwater. The effluent shall be sent to the clean pluvial system, provided it complies with therequirements of the applicable environmental legislation, otherwise it shall be sent to thedike.

20 COMPLETION EFFLUENTS

20.1 Description

Effluents from interventions in onshore oil wells from completion, recompletion, restoration,cleaning operations and changes in elevation method, fracturing, chemical treatments,formation and products tests, abandonment and other related activities.


20.2.1 Pluvial waters, floor washing water, in areas such as:

a) fluid tanks;b) platform;c) process pumps.


a) saline solutions;b) viscosified fluids;c) solutions with detergent;d) foamy fluids;e) acid fluids;f) alcoholic fluids;g) fluids with organic solvents;h) alkaline solutions;i) oil formation fluids;j) fluid of formation without oil;k) washings of fluid tanks.


Collection shall be done for tanks with installations allowing the transfer of effluent to atreatment station by truck or to a dike.



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Completion Fluidsand Solutions

from Well

Fluid Tanks forPreparation,

Accumulation andNeutralization

DrillingDike

Suitable Treatment orDisposal in ReceivingBody According to theApplicable Legislation

Flare

TreatmentSystem

By Truck

Return

FIGURE 7 - DIAGRAM OF ROUTING AND PRELIMINARY TREATMENT OFCOMPLETION EFFLUENT SYSTEM

20.4.2 The acid and alkaline fluids shall be neutralized before being disposed of into thedike.

20.4.3 The saline solutions containing chromate (Cr VI) shall undergo a reduction andprecipitation process before being sent to the dike.

20.4.4 For combustible fluids (fluids from formation with oil and fluids with organic solvents),it is recommended that they be burned or transported to a treatment station.[Recommended Practice]

20.4.5 The other fluids mentioned in item 20.2.2 shall be sent to the dike. If any fluidconsiderably modifies the physical-chemical characteristics of discharge of effluent from thedike into the receiving body, it shall be sent to a treatment station.

20.4.6 The dike effluent shall be sent to the receiving body when it complies with the currentenvironmental legislation; otherwise, it shall be transferred to a treatment station.

21 SPECIAL SYSTEMS

21.1 Description

Systems to which effluents presenting proper characteristics which do not permit them to beclassified into the systems described above or which require special precautions for theircollection, flow and preliminary treatment are sent.

21.2 System for Effluents which Can be Contaminated with Tetraethyl Lead (TEL) ofEthylation Units

This system includes effluents collected at the following points:

a) scale-tank area;b) covered platform for storage and emptying of drums;c) parking area for unloading trucks and/or containers with TEL;d) area for parking of TEL trucks and storage of containers with TEL;e) equipment for transferring and mixing TEL, connected to gasoline or kerosene

lines.

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21.2.1 Collection and Flow

Effluents shall be conveyed through piping system and a special passage box to anintercepting well.

21.2.2 Preliminary Treatment

Effluents collected at the intercepting well for retaining tetraethyl lead (TEL) shall be takendirectly to the oily system. The decanted TEL retained on the bottom of the intercepting wellshall be collected and placed in a drum.

21.3 Effluents Contaminated with Alcohol/MTBE

These are effluents from leaks and/or spills of these products, particularly in the yards ofloading/unloading areas and in the contained areas of their pump stations, either mixed ornot with pluvial waters, floor washing waters or fire-fighting waters.

Notes: 1) In order to minimize the possibility of these residues being generated, theseareas subject to contamination shall be covered whenever possible.

2) This system does not apply to truck loading areas, where alcohol/MTBE a

Documents

NI-0038