Specification Package Plant-

8/12/2019 Specification Package Plant-

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TECHNICAL SPECIFICATION FOR

WASTEWATER TREATMENT SYSTEM

PART 1: PACKAGE PLANT


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CONTENTS

1 SCOPE 1

2 NORMATIVE REFERENCE 1

3 TERMS AND DEFINITIONS 1

4 FUNDAMENTAL REQUIREMENTS 34.1 Endorsement 34.2 Packaged Components of Package Plant 34.3 Arrangement of Tank 44.4 Flow Splitter and Distribution 44.5 Code and Model 44.6 Marking and Labelling 5

4.6.1 Prefabricated Tank 54.6.2 Inspection Cover 54.6.3 Permanence and Visibility 5

5 OPERATIONAL PERFORMANCE 55.1 Process 55.2 Civil and Structure 6

5.2.1 General 65.2.2 Foundation Work 65.2.3 Prefabricated Tank 6

5.2.3.1 Design Basis 65.2.3.2 Tank Integrity 75.2.3.3 Tank Strength 75.2.3.4 Watertightness 75.2.3.5 Partition Wall 75.2.3.6 Joints 8

5.2.4 Anchorage 85.2.5 Backfill Material 85.2.6 Retaining Wall 8

5.3 Design Service Life 8

6 PERFORMANCE CRITERIA 96.1 Unit Process 9

6.1.1 Effluent Weir 96.1.2 Sludge Treatment 9

6.1 Piping System 96.2.1 General 96.2.2 Inlet and Outlet Pipe 96.2.3 Air Pipe 96.2.4 Sludge Transfer Pipe 106.2.5 Effluent Pipe 10

6.3 Pumping System 106.3.1 Pump 106.3.2 Duct Foot, Transfer Pipe and Guide Rail 11

6.4 Air Lift System 116.5 Diffuser 116.6 Valve 116.7 Inspection Opening and Cover 116.8 Flow Distribution Chamber 136.9 Lifting Device 136.10 Control and Instrumentation 13


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7 CONSTRUCTION OF PREFABRICATED TANK 137.1 Glass Fibre Reinforced Plastic (FRP) Tank 13

7.1.1 Design Basis 137.1.2 Material 137.1.3 Composition 137.1.4 Thickness 13

7.1.5 Surface Finish 147.1.6 Physical Properties 14

7.2 High Density Polyethylene (HDPE) Tank 147.2.1 Design Basis 147.2.2 Material 147.2.3 Composition 157.2.4 Thickness 157.2.5 Surface Finish 157.2.6 Physical Properties 15

7 DELIVERY AND INSTALLATION 15

9 TESTING AND CERTIFICATION 16

9.1 Type Testing 169.2 Process Performance Evaluation and Testing 169.3 Test Record 16

ANNEX

Annex A Normative ReferenceAnnex B External hydrostatic pressureAnnex C Internal pressureAnnex D Lateral loads for non-cylindrical shape tanksAnnex E WatertightnessAnnex F Partition WallAnnex G Joints

Annex H Thickness

LIST OF FIGURE

Figure 4.1 Scope of Biological Treatment System for Package PlantFigure 4.2 Typical Concepts of Flow Splitter and Flow DistributionFigure 4.3 Typical Marking and Labelling for Inspection CoverFigure 6.1 Typical Pipe Support and BracketFigure 6.2 Typical Manhole Cover

LIST OF TABLE

Table 4.1 Maximum Numbers of Prefabricated Tanks for Package PlantTable 4.2 Range of Model for Package PlantTable 5.1 Minimum Design Service Life for Package Plant ComponentsTable 6.1 Material of Construction for the ValvesTable 6.2 Performance Requirements for Inspection CoverTable 7.1 Physical Properties of Glass Fibre Reinforced Plastic Tanks at 27C 5CTable 7.2 Physical Properties of High Density Polyethylene Tanks at 27C 5CTable 9.1 Requirements of the Type TestsTable 9.2 Criteria for Process Performance Evaluation and Testing of Package Plant


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Part 1: Package Plant

1

STANDARD SPECIFICATION FOR WASTEWATER TREATMENT SYSTEMPart 1: Package Plant

1 SCOPE

This Specification specifies operational performance requirements and performance criteria forpackage plant used for the treatment of domestic wastewater for a population equivalent between 150and 5000. The Specification specifies technical means of compliance and provides test specificationsto enable performance measurement of package plant.

The subjects in the Specification deal with the features of functional design, material, construction,installation and testing that are a means of compliance with the operational performance requirementsof the package plant. The focus is made to the packaged biological treatment system comprisingprefabricated components of tanks, piping, aeration and pumping system, flow distribution and otherancillary equipment, control and instrumentation.

The intended use of this Specification are to reveal a practise worthy of consideration in ensuring theeffective operational performance, reliability and durability of package plant to give the intended

results under normal operating conditions along its serviceable life. The requirements specified hereinare also to enable the testing agency to check the conformance of the package plant to theSpecification and to allow certification and accreditation in reference to the measurable componentsof performance for quality assurance.

This Specification does not cover the design of treatment processes, mechanical and electricalcomponents and control and instrumentation. All these components shall be designed to bestengineering practice in compliance with the Guidelines and Standards recognised by the Commission,bylaws, regulations and other regulatory agencies requirements relevant to the aspects.

2 NORMATIVE REFERENCE

The documents and publications that are indispensable and referred to for the application of thisSpecification are listed in Annex A.

3 TERMS AND DEFINITIONS

For the purpose of this Specification, the terms and definitions given in MS 1228 and following apply:

3.1 AnchorageA device or technique for holding the tank in the ground against hydrostatic uplift pressure

3.2 AssemblyMechanical equipment that can be removed and replaced as a whole

Note: Example for an assembly is a pump, an air blower, a diffuser

3.3 Design Service LifeOperating time until breakdown of structural and machinery element under design loading, which isreached by a certain percentage of the elements tested

Note: Design service life is different from both the warranty time and average service life of use, as used for costefficiency calculations.

3.4 DesludgingRemoval of accumulated sludge from sludge holding tank

3.5 ExtensionA structure used to bring the inspection cover to finished ground level


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3.6 EquipmentAny component which is installed in, mounted on, attached to, or operated on structures, in theperformance of their intended function

3.7 Inspection OpeningAn opening in the top surface of the prefabricated tank fitted with a cover to allow access for visual

inspection of the interior of the tank and contents, removal of equipment and desludging, but notintended to allow people to enter a tank

3.8 LaminateFor glass fibre manufacture, the set layer or layers of reinforcement impregnated with polyester orother resin forming a thick structural membrane, excluding the gel-coat

3.9 Lateral LoadThe load applied sideways onto a buried tank due to the combined effects of soil, water and traffic

3.10 Operational PerformanceThe functions that a system has to perform in order to operate as defined

3.11 Package PlantA prefabricated factory-built sewage treatment installation

3.12 Partition WallAn internal wall within a prefabricated tank

3.13 Performance CriteriaThe qualitative or quantitative description of the operational performance

3.14 Production batchA clearly identifiable collection of units, manufactured consecutively or continuously under the sameconditions, using material to the same specification

3.15 SampleOne or more units of product drawn from a batch, selected at random without regard to quality, thenumber of units of product in the sample being the sample size.

3.16 Serviceable LifeThe period of time in which with only normal and routine maintenance, the package plant andassociated fittings and equipment perform satisfactorily without failure

3.17 StructureAny construction and its components built for the accommodation of equipment

3.18 Type testingTesting, normally conducted by accredited laboratory performed to demonstrate that the material,

component, joint or assembly is capable of conforming to the requirements given in the Specifications

3.19 Unit ProcessAny structure including any related equipment which is used as a process stage and which can beisolated from other parallel, upstream or downstream structures

Note: Examples for a unit are a screen chamber, an aeration tank, a clarifier, a sludge holding tank.


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4 FUNDAMENTAL REQUIREMENTS

For package plant serving the population equivalent between 150 and 5000, the requirements in thisSpecification shall be in addition to those specified in Malaysian Sewerage Industry Guideline (MSIG),Vol. IV.

4.1 Endorsement

The calculations, engineering design and drawings of prefabricated packaged biological treatmentsystem of the package plant shall be duly endorsed by the manufacturer for each approvedapplication. The endorsement shall include the components of process, structural, hydraulic,mechanical, electrical, control and instrumentation.

The Professional Engineers who are responsible in endorsing the calculations, engineering designand drawings for the entire package plant covering inlet works, outlet works, packaged biologicaltreatment system and foundation shall ensure the installation and construction for all thesecomponents at site conform to the design intent.

4.2 Packaged Components of Package Plant

The biological treatment system in which the scope extend 300 mm from the inlet pipe of firstprefabricated tank/ chamber to 300 mm from the outlet pipe of final prefabricated tank/ chamber asshown in Figure 4.1 including:

a) inter tank piping;

b) air piping for aeration, mixing and air lift system;

c) pumping for sewage and sludge transfer;

d) mechanical equipment;

e) electrical, control and instrumentation components; and

f) concrete chamber constructed within this area

shall be packaged in terms of layout, arrangement, biological processes, piping system, pumpingsystem, aeration system, air lift system together with the size, type and numbers of mechanicalequipment, electrical, control and instrumentation components equipped in the systems. Thedimensions of each prefabricated tank shall be fixed.

Figure 4.1 Scope of Biological Treatment System for Package Plant

Note: This layout shown is an indicative view of typical package plant for reference purposes

Legend:

Scope SHT Sludge holding tank FS Flow splitter

BT Balancing tank AET Aeration tank CL Clarifier

DC Distribution chamber AT Anoxic tank

FS

BlowerHouse

300 300

BT

CL

CLAET AT

SHT

AET AT

SHTInletWorks

DC

OutletWorks


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4.3 Arrangement of Tank

Provided that it is proven in both process and hydraulic design, the prefabricated tanks in seriescarrying out a complete process of a unit of process tank shall be considered as one (1) tank.

4.4 Flow Splitter and Distribution

As a mechanism to allow the diversion of flow, the flow splitter shall be provided in the flow systemdistributing to maximum two (2) numbers of unit process tank and the flow distribution shall beprovided in the flow system distributing to maximum four (4) numbers of unit process tank.

Figure 4.2 shows the typical concept of flow splitter and flow distribution in package plant application.

4.5 Code and Model

The coding requirements to name the model of package plant shall follow the sequence code ofidentification with maximum characters as shown below.

AAA / BBB / 1234 / CCC Example: XXS/HKA/3000/CAS

where; AAA - Name of companyBBB - Brand / Model1234 - Actual population equivalent of package plantCCC - Type of treatment process

The model of package plant shall be limited to the range of population equivalents with minimumintervals as shown in Table 4.2.

Table 4.2 Range of Model for Package Plant

Model Range Interval

150 P.E ~ 1000 P.E 50

1200 P.E ~ 3000 P.E 200

3500 P.E ~ 5000 P.E 500

CL

Figure 4.2 Typical Concepts of Flow Splitter and Flow Distribution

Flow Distribution

CL2

1CL

CL AET3 AET 1

CL4

AET CL AET2

Flow Splitter

Stoplog

Stoplog


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4.6 Marking and Labelling

4.6.1 Prefabr icated Tank

Each prefabricated tank shall be marked, as a minimum, with the following information:

a) Manufactures name or trademark.b) Manufacturing serial number.

c) Manufacturing date (MM/YY).

d) Diameter and capacity.

e) Standard number.

f) Certification number.

4.6.2 Inspection Cover

Each inspection cover shall be properly marked and labelled as typically shown in Figure 4.3 with the

following information to ease identification of the unit process for the treatment system.

a) Model of the package plant.

b) Unit process for the tank.

c) Dimension of the tank (Length x Width x Diameter/ Height).

d) Standard number.

e) Certification number.

4.6.3 Permanence and Visib ili ty

All marking and labelling shall be permanent, legible and clearly visible at time of installation. The

marking and labelling shall be stencilled, laminated or embossed to the tank.

Figure 4.3 Typical Marking and Labelling for Inspection Cover

5 OPERATIONAL PERFORMANCE

5.1 Process

Under normal operating conditions of sewage treatment that receive medium concentration ofdomestic raw sewage, the package plant shall be able to provide absolute Standard A effluent quality

according to Environmental Quality Act, 1979. The package plant shall also be capable:


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a) to encourage and provide sufficient amount of mixed liquor suspended growth (MLSS) in thetreatment system;

b) to provide minimum dissolved oxygen concentration of 2 mg/l to prevent oxygen diffusionlimitation from hindering substrate removal by the microorganism;

c) to provide sufficient mixing to keep the sludge in suspension without causing any settlement of

sludge in any part of the relevant unit process tanks, which require mixing;

d) to allow entry of wastewater with the minimum of disturbance to surface layers by maintaininghydraulic flow and patterns throughout the treatment system without causing any increment insurface loading and velocity current;

e) to provide good quality of sludge with normal settling characteristics indicated by sludge volumeindex (SVI30) and sludge settled volume (SSV30) of the respective treatment system adopted;

f) to avoid likelihood of blockage in sewage and sludge transfer system within the package plantboundary during its serviceable life.

5.2 Civil and Structure

5.2.1 General

The civil and structural components of package plant shall be designed by a relevant qualifiedProfessional Engineer, using appropriate design methodologies and relevant Standards to bestengineering practice.

The structures and construction of the package plant shall be:

a) stable to bear all loads during construction, operation and maintenance periods such as waterpressures, static and dynamic forces being induced by the equipment;

b) able to prevent the likelihood of damage from superimposed loads or normal ground movement;

c) resistant against chemical and biological attack from wastewater, sludge, air and gas components

and against temperature changes as appropriate;d) able to retain the structural integrity including alignment, orientation and levelling and function

properly with only normal maintenance over their serviceable life.

5.2.2 Foundation Work

The foundation works for the installation of major and auxiliary components for the package plant shallbe designed and constructed so that component such as inspection chamber shall be secured toavoid disruption to the operation and maintenance works and process of the system. The foundationshall be able to prevent the possibility of sludge settlement, differential settlement between structuresand between structures and equipment such as pipeline.

5.2.3 Prefabr icated Tank

5.2.3.1 Design Basis

The prefabricated tanks and its foundation shall be designed to achieve the required design servicelife and long term structural integrity and shall meet the worst-case conditions not limiting to:

a) when the prefabricated tanks are fully emptied; and

b) during high groundwater conditions.

The construction and installation of the prefabricated tanks shall resist hydrostatic uplift pressures i.e.uplift loads from groundwater and be protected against floatation in areas of high water table level orwhen the tank is emptied. The bottom of an excavation for the prefabricated tanks shall provide a

uniform base to support the tanks in a level position.


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The structural design of a prefabricated tank shall consider all factors that can affect the strength andintegrity of the tank, like soil conditions and area of installation so that the entire structure of theprefabricated tanks and its associated components are integrally sound. The resistance to loadincurred during transport and installation shall also be considered in the structural design of the tanks.

5.2.3.2 Tank Integrity

The integrity of the prefabricated tanks shall be such that no full penetration crack shall be developeda width greater than 0.1 mm during any stage of production. Further widening or lengthening of anycrack shall not occur during subsequent handling, installation or use.

5.2.3.3 Tank Strength

All prefabricated tanks shall be structurally designed to withstand the maximum earth load equivalentto an overburden depth of 1000 mm at maximum depth of cover of 1000 mm. The prefabricated tanksshall be capable of withstanding loads imposed on its roof and walls i.e. top and lateral loads duringand after installation. Account shall be taken of any load imposed on the tank structure as a result ofthe technique used to anchor the tank in the ground.

The following verification test methods shall be carried out to authenticate the strength of theprefabricated tanks to withstand:

a) External hydrostatic pressureWhen tested in accordance with Annex B, the prefabricated tanks shall not leak or fail of othermeans after holding the external water pressure load equal to the tank diameter plus 1000 mm ofoverburden depths for 24 hrs and additional superimposed negative internal pressure equal to thedepth of cover of 1000 mm times 9.78 kPa/m plus 18 kPa for 1 minutes.

b) Internal pressureWhen tested in accordance with Annex C, the prefabricated tanks with a diameter 3000 mm orless shall withstand pressure of up to 25 psig (172.5 kPa) and for prefabricated tanks with adiameter greater than 3000 mm shall be able to withstand pressure of up to 15 psig (103.5 kPa).

c) Lateral loads for non-cylindrical shape tanksWhen tested in accordance with Annex D, there shall be no structural failure, undue distortion orin surface cracking in excess of that permitted in 5.2.3.2 due to external hydrostatic groundwaterand soil loading of 11 kPa/m depth acting on an empty tank.

d) Hydrostatic upliftAn installed prefabricated tank shall not move when subjected to uplift forces generated bysurrounding groundwater or be stressed to cause such cracks in excess of those in 5.2.3.2.

e) Impact ResistanceWhen tested in accordance with ASTM D3029, the internal tank wall surface for prefabricatedFRP and HDPE tanks shall withstand the impact of 0.36 kg (0.8 lb) steel ball at a distance equalto the diameter of the tank above the tank bottom.

5.2.3.4 Watertightness

For cylindrical prefabricated tanks complete with attachments, when tested in accordance with AnnexE, tanks with 3000 mm diameter and less, shall not leak at pressure level of 5 psig (34.5 kPa) andtanks greater than 3000 mm diameter, shall not leak at pressure level of 3 psig (20.7 kPa).

For other shape prefabricated tanks, when tested in accordance with Annex E, it shall have noleakage and no damp patches.

5.2.3.5 Partition Wall

When a partition wall is used to divide the prefabricated tanks into different compartments,assumptions regarding the arrangement of liquid loading shall cause the most critical effects such as:

a) Particular attention shall be paid to possible sliding and overturning due to differential moment;


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b) The partitions shall be structurally sound and fixed without diminishing the integrity of the tank;

c) The tank partition wall during pumping out shall not collapse, or permanently deformed. Averification test shall be in accordance with Annex F.

5.2.3.6 Joints

The joints between fittings and the wall of prefabricated tanks and between tank components such asthe wall and lid, shall have a durable seal, be watertight, and have sufficient integral strength andflexibility to maintain a sound structure. The verification test for joints around fittings shall be made inaccordance with Annex G.

5.2.4 Anchorage

The anchor system consist of straps, cables, turnbuckles and anchor hooks shall have strength of atleast 1.5 times the maximum uplift force of an empty tank without backfill in place. All the anchorsystem components shall be made of Grade 304 stainless steel comply with ASTM A240/ A240M.

Details shall be provided by the prefabricated tank manufacturer with the installation instructions,which shall show the recommended relationship between levels in the tank, groundwater levelssurrounding the tank, and anchorage requirements.

5.2.5 Backf ill Material

The backfill material for the prefabricated tanks shall be of particle size and grading that allow thespecified relative compaction to be achieved with the intended compaction methods. The materialshall notcontain organic material that affect the backfill material performance and free of materialsthat be physically and chemically harmful to the tanks. The support and overlay material shall beplaced in layers of appropriate thickness for the method of compaction, to achieve the relativecompaction or soil modulus.

5.2.6 Retaining wall

The retaining wall shall be designed and checked accordingly by taking into account among others, allpossible factors involved contributing to the lateral earth pressure. The wall member shall also becapable of meeting serviceability requirements at site condition.

5.3 Design Service Life

The minimum design service life against defects, deterioration and total failure of the components forthe package plant shall be as Table 5.1 below.

Table 5.1 Minimum Design Service Life for Package Plant Components

Component Standards Design Service Life

Prefabricated FRP tankBS EN 4994, BS EN 13923 or

ASTM D4097 > 50 years

Prefabricated HDPE tank AS/NZS 4766 or CSA B66-05

Civil and structure BS 8110-1 > 50 years

Mechanical and electrical BS EN 12255-1 10 years

Control and instrumentation BS EN 12255-12 10 years

Corrosion resistance coating BS EN ISO 12944-1 to 8 10 years


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6 PERFORMANCE CRITERIA

6.1 Unit Process

6.1.1 Effluent Weir

The weir in sedimentation tank shall be accessible without causing obstruction and not posing anyhealth and safety issues. The weirs shall always be levelled for even distribution of flow. Slots in theweir shall be provided to allow for level adjustment during the installation stage. Flow through over theweir shall be calculated based on the actual type of weir used.

6.1.2 Sludge Treatment

The amount of wasted sludge, Qwasteshall be used to size the sludge holding tank. The amount of thewasted sludge in mass shall be balanced with the sludge accumulation rate in reference to thecomputed sludge age.

An adequate air mixing mechanism and air supply shall be provided in the sludge holding tank toensure the sewage content is sufficiently mixed to keep it in suspension, without causing any

hardened sludge settled at the bottom of the tank between the desludging periods of 30 days.

The sludge treatment by anaerobic digester shall not be allowed as it require intensive health andsafety requirements and control system, which is not suitable for operation and maintenance of thepackage plant within the serving population equivalent.

6.2 Piping System

6.2.1 General

The piping system for the package plant shall comply with the following criteria:

a) The arrangement of the piping system and interconnection pipes in the prefabricated tanks shall

not obstruct maintenance work of the equipment in the tanks;

b) All the buried piping shall be properly bedded and supported with the selected compacted fillmaterial;

c) All the above ground piping shall have a minimum distance of 75 mm from the ground level. Itshall be provided with a proper pipe support and bracket. The bracket shall be made steel coatedwith hot dipped galvanised in compliance with BS EN ISO 12944. The typical pipe support andbracket is shown in Figure 6.1;

d) The arrangement of the above ground piping shall minimise obstruction and maneuvrebility;

e) Any on-site installation or assemblies of pipe support that is attached to the prefabricated tankshall not be allowed;

f) No bending is allowed at any sewage distribution pipe excluding the force main piping. Instead, achamber shall be provided to cater for any change of direction in sewage flow.

6.2.2 Inlet and Outlet Pipe

All openings for pipes connection of the prefabricated tanks shall be pre-fitted at the factory with asocket, a spigot, a flange or a 300 mm length short piece of pipe. On-site drilling of openings for pipeconnection shall be prohibited.

6.2.3 Air Pipe

The air pipes that consist of air distribution pipes from blower, header pipes, drop leg/down pipes andother pipes to convey the air for aeration, mixing or air lift purposes shall be:

a) able to withstand maximum air temperatures generated by the blower and pressures of 25% morethan the design pressure of the blower;


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b) painted in green with the air flow direction be painted in white at maximum interval of 3 m;

c) above ground for the air distribution pipes from the blower to the unit processes;

d) properly bracketed with Grade 304 stainless steel U-bolt in compliance with BS EN 10088-1:2005for the down pipes to limit the movement of the diffusers;

e) designed to provide even and adequate air distribution to all relevant unit processes;

f) provided with instruments such as air gauge or pressure gauge for the pipes conveying air formixing and air lift purposes. The points to allow calibration shall be provided for the fixedinstrument, while points to allow measurement shall be provided for the portable instrument;

6.2.4 Sludge Transfer Pipe

All jointing to connect the sludge transfer pipes shall be double flange with Grade 304 stainless steelbolts and nuts in compliance with ISO 3506-1 to ISO 3506-3. No thread union or coupling shall beallowed in any jointing part of the pipes.

6.2.5 Effluent Pipe

The effluent discharge piping system that passes through or by-passes the disinfection treatmentfacility shall be designed so as not to cause any nuisance.

The invert level of the effluent pipe shall be at a minimum of 300 mm from the top water level of thereceiving watercourse.

6.3 Pumping System

6.3.1 Pump

The minimum control mechanism for the pumps installed within the package plant shall be:

a) automatic by float switch for sewage transfer pump;

b) automatic by timer and interlock with solenoid valve for return and waste sludge pump insedimentation tank;

c) manual by push button for sludge transfer pump to remove the sludge from sludge holding tank.

Non-submersible pumps shall be provided with parking bay with shade.

NOTES :-

1. ALL DIMENSIONS ARE IN MILIMETERS UNLESS OTHERWISE STATED.

10mm (MIN.) HOT DIPGALVANISED BOLTS AND NUTS

HOT DIPPED GALVANISED PIPEBRACKET AT AN INTERVAL OF2000mm C/C (MAX.)

CONCRETESLAB

PIPE

GL

75

(MIN.)

(MIN.)

75

(MIN.)

GL

(MIN.)

SAND BEDDING

50

50

Figure 6.1 Typical Pipe Support and Bracket


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6.3.2 Duck Foot, Transfer Pipe and Guide Rail

All pumps shall be completely installed with duck foot, guide rail and lifting chain comply with thefollowing requirements:

a) The duct foot shall be installed and assembled at the factory. No installation or assemblies at site

shall be allowed except for the connection of the transfer pipe and the guide rail;b) The guide rail shall be properly bracketed with U-bolt to secure the movement of the pump;

c) All fasteners of the duct foot shall be watertight;

d) The guide rail, lifting chain and U-bolt bracket shall be made of Grade 304 stainless steel incompliance with BS EN 10088-1.

6.4 Air Lift System

The solenoid valves shall be provided for intermittent air lift system for both return and waste sludgeand scum skimmer.

6.5 Diffuser

All diffusers shall be supported from the tank base and shall not be bolted to the bottom of the tank.The diffusers shall be removable and easy to re-install onto the diffuser support.

The support for the diffusers shall be made of non-corrosive material and shall be designed to suit theapplication. The support shall be capable to prevent buoyancy of the diffuser.

6.6 Valve

All valves shall be accessible and not obstruct maintenance work. The valves of 100 mm diameterand above shall be installed in the inspection chamber.

Selection of materials to be used in the construction of body and seal of the valves shall be inaccordance with the application in order to optimize functional reliability, fluid compatibility,serviceable life and cost. The material of the valve shall comply with requirements in Table 6.1 below.

Table 6.1 Material of Construction for the Valves

Type ofValve

StandardsMaterial of Construction

Body Parts in contact with sewage

SolenoidValve

-Brass and bronze. Polyamidematerials for plastic valves.

Austenitic corrosion-resistant steel

Gate Valve BS 5150 Ductile Iron Austenitic corrosion-resistant steel

Check Valve BS EN 12334 Ductile Iron Austenitic corrosion-resistant steel

6.7 Inspection Opening and Cover

The design and arrangement of the inspection cover in reference to the inspection openings shall beconsistent with the operational requirements of the package plant. The inspection cover shall beinstalled at any location on top of the tank except at assembly joints, rib or reinforced ring location.

The inspection cover shall have a size of 600 mm x 600 mm or 600 mm diameter and shall beequipped with a frame support together with hinge and handle made of Grade 304 stainless steel. Forinspection opening bigger than the size of inspection cover, bracing to support the cover made ofGrade 304 stainless steel shall be provided. All stainless steel Grade 304 shall comply with BS EN

10088-1.


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Y

Y

Y

Y

AAA/BB

B/1234

/CC

BALAN

CINGT

ANK

X

X

600

600

600

X

X

NOTES :-

1. ALL DIMENSIONS ARE IN MILLIMETERS UNLESS OTHERWISE STATED.

STAINLESS STEEL HINGE

30mm FONT SIZE

AAA/BBB/1234/CCBALANCING TANK

3.0(L)X3.5(W)X3.2(D)

GFRP/HDPE/CI MANHOLE COVER

STAINLESS STEEL HANDLE

STAINLESS STEEL HINGE


PREFABRICATED TANKGL

6 x 100 (min.)

STAILESSSTEEL HINGE

GFRP/HDPE/CI

MANHOLE COVER

PREFABRICATEDTANK

GL

STAINLESS STEELHINGE

30mm FONT SIZE

AAA/BBB/1234/CCBALANCING TANK

3.0(L)X3.5(W)X3.2(D)


STAINLESS STEEL HANDLE

STIFFENER

600

50

PLAN

PLAN

SECTION Y-Y

SECTION X-X

The inspection covers shall be securely fitted and attached to the opening and shall have themechanism preventing it from being accidentally shut. The collar of the opening to place theinspection covers shall be raised to a minimum height of 150 mm above ground level. The typicalinspection cover is shown in Figure 6.2.

150 (min)

150 min)

Figure 6.2 Typical Manhole Cover

The inspection cover shall provide an effective, durable and watertight seal and be able to withstand

superimposed loads at operating temperature of 27C to 35C with incorporation of thermal expansionand contraction complying with the requirements as shown in Table 6.2 below.

Table 6.2 Performance Requirements for Inspection Cover

Parameter Standards Performance Requirements

Load Bearing Capacity BS EN 12255-1 3.5 kN/m2

Maximum Deflection Limit BS EN 12255-110 mm or the span divided by 200,

whichever is smaller

Class BS EN 124 B 125

Personnel Load BS EN 124 125 kN for fully walk-able load

Design Safety Factor ANSI/ASCE 7-984:1 for allowable stresses shall be

met for all load combinations


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The inspection cover shall be sufficiently protected during its serviceable life, which similar to theprefabricated tanks against degradation due to exposure to UV light and corrosion due to exposure tocorrosive sewage environment.

6.8 Flow Distribution Chamber

The design and construction of the flow distribution chamber shall prevent any sedimentation. Theadjustable features shall be provided within the flow distribution chamber and shall be constructedusing one of the following material:

a) Reinforced concrete with a minimum of Grade C30 in compliance with BS 8007;

b) FRP with minimum thickness of 5.0 0.5 mm in compliance with BS EN 4994, BS EN 13923 orASTM D4097;

c) Steel plate coated with hot dipped galvanised of 140 m or high build tar epoxy coating of 200 mminimum dry film thickness. The steel plate and the coating shall comply with the requirements inEN 10163-2and BS EN ISO 12944-1 to BS EN ISO 12944-8 respectively;

d) Stainless steel of minimum Grade 304 in compliance with BS EN 10088-1;

e) Any other material that is approved by the Regulator to be used for this purpose.

6.9 Lif ting Device

The lifting device shall be installed so that to avoid direct loading to the structure of the prefabricatedtanks. Where fixed lifting device is provided, it shall be supported by the spread footing to ensureeven distribution of loads exerted by the weight of the devices.

6.10 Contro l and Instrumentation

The necessary measuring and control equipment shall be specified taking into account the installationconditions. This applies both to its location within the package plant and to the layout and size of thestructures as a function of the type of equipment in compliance with BS EN 12255-12.

7 CONSTRUCTION OF PREFABRICATED TANK

7.1 Glass Fibre Reinforced Plastic (FRP) Tank

7.1.1 Design Basis

The seams and openings of the glass fibre reinforced plastic tanks shall be designed in accordancewith BS EN 4994, BS EN 13923 or ASTM D4097. The tanks shall be able to operate under the

temperature of 17C to +50C.

7.1.2 Materials

The resin shall be unsaturated thermosetting polyester or epoxy resin that has minimum heatdistortion temperature of 65C when tested in accordance with ISO 75-2. The resin shall contain notless than 50% w/w, by mass of non-volatile materials, no pigment or fillers and not more than 2% w/wof thixotropic agents.

The glass fibre, which used as the reinforcing material shall be suitable grade of glass fibre having aglass finish compatible with the resin used and complying with BS 3396.3, BS 3749, BS EN 14020-3and BS EN 14118-3, as appropriate. The C-glass of fibre shall be added for corrosion protection.

7.1.3 Composition

The laminate shall contain not less than 30% w/w of glass fibre content. No fillers or pigments shall beincluded in the laminate. Any parts or surfaces that are exposed to the sun shall be constructed withultraviolet-light inhibitors added to the laminate.


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7.1.4 Thickness

The minimum cylindrical wall and end panel thickness for cylindrical tanks shall be 8.0 0.5 mm. Fordifferentially shaped of tank, the minimum thickness of the structural tank wall shall be 8.0 0.5 mm.

The thickness of the partition wall and all other internal components shall be at least 5.0 0.5 mm. Averification test shall be in accordance with Annex H.

7.1.5 Surface Finish

The exterior surface shall be relatively smooth with no sharp projections and be free of blisters largerthan 15 mm in diameter, delaminating, and fibre show.

The interior surface shall be resin rich with no exposed fibres. The surface shall be free of crazing,delamination, blisters and wrinkles of 3.5 mm or greater in depth.

7.1.6 Physical Properties

In addition to the tests specified in 5.2.2, the following type test to verify the physical properties of the

glass fibre reinforced plastic tanks at 27C 5C shall be carried out using test specimens prepared inaccordance with ISO 1268-4.

Table 7.1 Physical Properties of Glass Fibre Reinforced Plastic Tanks at 27C 5C

Criteria Physical Properties Testing Standards

Flexural Strength 110 MPa ISO 14125

Modulus of Elasticity 4830 MPa ISO 14125

Impact Resistance No surface cracks visible to normalor corrected normal vision

ISO 179-2

Barcol Hardness 35 BS EN 13923

Water Absorption 0.75% ISO 62

Glass Fibre Content 30% w/w ISO 1172

Tensile Strength 65 MPa ISO 527-4

Tensile Elongation 1.5%. ISO 527-4

Tensile Modulus 7000 MPa ISO 527-4

Specific Gravity 1.5 ISO 62

Fire Rating < 25s ASTM E84

Class 1 BS476

7.2 High Densi ty Polyethylene (HDPE) Tank

7.2.1 Design Basis

The seams and openings of the high density polyethylene tanks shall be designed in accordance withAS/NZS 4766 or CSA B66-05.

7.2.2 Materials

The polymer resin used shall be a minimum of PE 80 with density 940 kg/m3 970 kg/m

3in the form

of powders, granules or pellets with no more than 10% of recycled materials. The materials shall be

as uniform in composition and size and as free of contamination.


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7.2.3 Composition

The carbon black or titanium dioxide shall be added to the polymer resin as UV stabiliser and shall

contain 2.5% 0.5% by mass with dispersion of not more than Grade 3 and toluene extract of notmore than 0.10% m/m.

7.2.4 Thickness

The minimum thickness of the tank walls, partition wall, other internal components, base and accessopening covers shall be 6.0 0.5 mm. A verification test shall be in accordance with Annex H.

7.2.5 Surface Finish

The exterior surface shall be ribbed, relatively smooth and impervious to liquid.

The interior surface shall be smooth and of even texture. The surface shall be free from surfaceimperfections, which detract from the performance of the tank in use.

7.2.6 Physical Properties

In addition to the tests specified in 5.2.2, the following type test to verify the physical properties of thehigh density polyethylene tanks at 27C 5C. The test specimens prepared shall reflect themanufacturing process and typical cross section of the tank. The specimens shall be manufactured atthe same time as the tanks produced for installation.

Table 7.2 Physical Properties of High Density Polyethylene Tanks at 27C 5C

Criteria Physical Properties Testing Standards

Flexural Modulus 640 MPa to 1200 MPa ISO 178

Charpy Impact 45 KI ISO 179

Shore Hardness 62 ISO 868

Tensile Strength 17 to 28 MPa ISO 527-4

Tensile Elongation 200% ISO 527-4

Tensile Stress at Yield 23 MPa ISO 527-4

Tensile Modulus 22 MPa ISO 527-4

Vicat Softening Temperature 80 C ISO 306

Melt Index 0.58 ISO 306

Thermal Conductivity 0.4 W/mC ASTM E1225

8 DELIVERY AND INSTALLATION

The manufacturer/supplier shall properly plan the delivery route so as not to cause any damage toroad facilities and harm to road users.

The package plant shall be installed and constructed under the supervision of a Qualified Person andin accordance with detail plans approved by the Commission or other relevant regulations authority.An inventory list of every item to be installed shall be provided and to be checked against theapproved construction drawings. The list shall be endorsed by the Qualified Person.

No fabrication or moulding of any part of the prefabricated tanks and pipe holes drilling shall be

allowed at the site. All jointing and pipe holes connection shall be factory fabricated and moulded.


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9 TESTING AND CERTIFICATION

9.1 Type Testing

Table 9.1 sets out the requirements for the type testing, which the validity period for the test reportshall be limited to five (5) years. Where there is any change in design that affects the particular

performance or requirement or any change in process or material, the type testing shall be conductednot governing by the validity period of the test report.

In the event of a test failure, further product within the batch of production shall be tested. If the firsttwo randomly selected additional tanks meet the requirements, the batch shall be deemed to meet thetest requirements. If one of the additional tanks fail, the batch shall be rejected or every tanksubjected to the relevant test.

The product certification for package plant shall be carried out to provide independent assurance ofthe claim by the manufacturer that the package plant complies with this Specification and consistentlyconform to the requirements of this Specification. The certification shall meet the criteria described inISO/ IEC Guide 28, and full type testing from independently sampled production and subsequentverification of conformance.

9.2 Process Performance Evaluation and Testing

The process performance evaluation and testing shall be mandatory for all package plants. Aminimum of three (3) assessments at different day shall be conducted for a package plant that hasbeen installed for more than two (2) years. All tests and samplings for the performance evaluation andtesting shall be carried out by an accredited laboratory with the verification from the operator on thedata and sampling collected. Table 9.2 showed the criteria for the evaluation and testing.

The number of package plants to be sampled shall be calculated based on the 5% installed units onall ranges of models and for package plants installed with less than 20 units, the performance ofminimum three (3) installed units shall be evaluated and tested. Report on the overall status of theinstalled units shall be reported on a yearly basis to the Commission.

9.3 Test Record

The report shall include, not limiting to the following information for each test specimen:

a) Identification of person and organisation carrying out the test;

b) Identification of the sample tested;

c) Date of test;

d) The test result; and

e) Reference to the test method.


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Table 9.1 Requirements of the Type Tests

CharacteristicsPerformance

Requirements andCriteria Clause

Requirements Test Method

Design and constructi on

Hydraulic performance

5.2.3.7 Joints Annex G

5.2.3.6 Partitions Annex F

5.2.3.5 Watertightness Annex E

6.2.2 Inlet and outlet pipe Design review

6.7Inspection opening andcover

Design review

4.3 Dimension of tank Design review

Structural integrity

5.2.3.3 (a) External hydrostatic pressure Annex B

5.2.3.3 (b) Internal pressure Annex C

5.2.3.3 (e) Hydrostatic uplift Design review

5.2.3.3 (c) Lateral load Annex D

5.2.3.3 (f) Impact resistance ASTM D3029

Marking 4.7 Marking and labelling Design review

Materials and Manufacture

Glass fibre reinforcedplastic tank

7.1.2 Material Evidence by wayof appropriatemanufacturer

documentation ofapprovals or tests

7.1.3 Composition

7.1.4 Surface finish

7.1.5 Thickness Annex H

7.1.6 Physical properties 7.1.6

High densitypolyethylene tank

7.2.2 Material Evidence by wayof appropriatemanufacturer

documentation ofapprovals or tests

7.2.3 Composition

7.2.4 Surface finish

7.2.5 Thickness Annex H

7.2.6 Physical properties 7.2.6


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Table 9.2 Criteria for Process Performance Evaluation and Testing of Package Plant

Criteria DescriptionStandard Referencefor Testing Method

Results

Date/ Time

WeatherbilityCondition of Plant

Status of mechanicalequipment

Current flow/capacity

Flow condition

Influent characteristics

BOD5 APHA 5210-B

COD APHA 5220-C

TSS APHA 2540-D

Oil and Grease APHA 5520-B

pH APHA 4500 H+-B

Ammonical Nitrogen APHA 4500-NH3E

Aeration tank characterist ics

MLSS APHA 2540-D

Dissolved Oxygen APHA 4500 O-G

Sludge Settleability (SSV30) APHA 2710 C

Sludge Volume Index (SVI30) APHA 2710 D

Sludge settlement Sludge judge

pH APHA 4500 H+-B

Temperature APHA 2550 B

Clarifier characteristics

Sludge Blanket Sludge judge

Effluent characteristics

BOD5 APHA 5210-B

COD APHA 5220-C

TSS APHA 2540-D

Oil and Grease APHA 5520-B

pH APHA 4500 H

+

-BAmmonical Nitrogen APHA 4500-NH3E

Total Kjedahl Nitrogen APHA 4500NorgB


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ANNEX A

NORMATIVE REFERENCE

AS 3750.2 Paints for steel structure-ultra high-build paint

AS/NZS 1546.1 On-site domestic wastewater treatment units Part 1: Septic TankAS/NZS 1546.2 On-site domestic wastewater treatment units Part 3: Aerated wastewater

treatment systemsAS/NZS 4766 Polyethylene storage tanks for water and chemicals

ISO 62 Plastics Determination of water absorptionISO 75-2 Plastics Determination of temperature of deflection under load Plastics and

eboniteISO 75-3 Plastics Determination of temperature of deflection under load High strength

thermosetting laminates and long fibre reinforced plasticsISO 179-1 Plastics Determination of Charpy impact properties Non-instrumented impact

testISO 179-2 Plastics Determination of Charpy impact properties Instrumented impact test

ISO 306 Plastics Thermoplastic materials Determination of Vicat softeningtemperature

ISO 868 Plastics and ebonite Determination of indentation hardness by means of adurometer (Shore hardness)

ISO 3506-1 Mechanical properties of corrosion resistant stainless steel fasteners Part 1:Bolts, screw and studs

ISO 3506-2 Mechanical properties of corrosion resistant stainless steel fasteners Part 2:Nuts

ISO 3506-3 Mechanical properties of corrosion resistant stainless steel fasteners Part 3:Set screws and similar fasteners not under tensile stress

ISO 527-1 Plastics Determination of tensile properties General principlesISO 527-2 Plastics Determination of tensile properties Test conditions for moulding and

extrusion plastics

ISO 527-4 Plastics Determination of tensile properties Test conditions for isotropic andorthotropic fibre reinforced plastics composite

ISO 14125 Fibre reinforced plastics composites Determination of flexural propertiesISO/IEC GUIDE 7 Guidelines for drafting of standards suitable for use for conformityassessment

ASTM A240/A240M Standard specification for chromium and chromium-nickel stainless steel plate,sheet and strip for pressure vessels and for general applications

ASTM D3029 Test method for impact resistance of flat, rigid plastic specimens by means of atup (falling weight)

ASTM D4097 Standard specification for contact moulded glass fibre reinforced thermoset resincorrosion resistant tanks

ASTM E84 Standard test method for surface burning characteristics of building materialsASTM E1225 Standard test method for thermal conductivity of solids by means of the

guarded-comparative-longitudinal heat flow technique

BS EN ISO 1461 Hot dipped galvanised coatings on fabricated iron and steel articles.Specifications and test methods.

BS EN 12334 Industrial valves Cast iron check valvesBS EN ISO 12944-1 Paints and varnishes. Corrosion protection of steel structures by protective paint

systems. General introduction.

BS EN 124 Gully tops and manhole tops for vehicular and pedestrian areas Designrequirements, type testing, marking, quality control

BS 4994 Specification for design and construction of vessels and tanks in reinforcedplastics

BS 5150 British Standard Specification for cast iron gate valveBS 8007 Code of practice for design of concrete structures for retaining aqueous liquidsBS 8110-1 Structural use of concrete. Code of practise for design and construction


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BS EN 10088-1 Stainless steels. List of stainless steelsBS EN 10088-2 Stainless steels. Technical delivery conditions for sheet/plate and strip of

corrosion resisting steels for general purposes.BS EN 12255-1 Wastewater Treatment Plants Part 1: General construction principlesBS EN 12255-11 Wastewater Treatment Plants Part 11: General data requiredBS EN 12255-12 Wastewater Treatment Plants Part 12: Control and automation

BS EN 13923 Filament wound FRP pressure vessels. Materials, design, manufacturing andtesting

ANSI/ASCE 7-98 Minimum Design Loads for Buildings and Other StructuresCSA B66-05 Design, material and manufacturing requirements for prefabricated septic tanks

and sewage holding tanks


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ANNEX B

DETERMINATION OF EXTERNAL HYDROSTATIC PRESSURE (EXTERNAL PRESSURE TESTAND INTERNAL VACUUM TEST)

(Normative)

B1 SCOPE

This Annex outlines a method of testing external hydrostatic pressure for a unit of prefabricated tank.

B2 PRINCIPLE

The tank is subjected to external hydrostatic pressure and is then examined for signs of leakage.

Test tanks of each diameter used. If tanks with equal diameter, but of different lengths, testing of thelongest tank shall confirm performance of shorter lengths provided that the wall thickness is constant.If wall thickness is varies with length, test each tank to prove conformance.

B3 TESTING

B3.1 Test Conditions for External Pressure Test

a) Install the empty tank in a test pit using the specified anchoring system and the specifiedoverburden depth and cover to comply with clause 5.2.3.3 (a);

b) Fill the pit with water to such a level that the tank is submerged to its maximum specifiedoverburden depth and cover;

c) Allow the tank to remain submerged for 24 hours;

d) While the tank is still submerged, it is to be subjected for 1 minute to a partial internal vacuum sothat the internal pressure on the tank is 29 kPa less than the external pressure imposed by thehydrostatic head.

B3.2 Test Condit ions for Internal Vacuum Test

a) Seal the empty tank and apply an internal vacuum calculated as per given in equation B1 below.

V = (1/2 D + h) x 0.88 inches Hg/ft (B1)

where; V is the vacuum in inches Hg,

D is the tank diameter in feet, and

h is the maximum specified cover depth in feet, but not less than 3 feet.

b) Hold the vacuum for 60 5 min and check for damage to the tank.

B4 TEST CRITERIAUnder external pressure test, the test tank shall not implode or otherwise be damaged.

Under internal vacuum test, each tank must withstand without rupture, an internal partial vacuumaccording to the equation.


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ANNEX C

DETERMINATION OF INTERNAL PRESSURE (INTERNAL PRESSURE TEST)

(Normative)

C1 SCOPE

This Annex outlines a method of testing internal pressure for a unit of prefabricated tank.

C2 PRINCIPLE

The tank is subjected to internal pressure and is then examined for signs of leakage.

Test tanks of each diameter used. If tanks with equal diameter, but of different lengths, testing of thelongest tank shall confirm performance of shorter lengths provided that the wall thickness is constant.If wall thickness is varies with length, test each tank to prove conformance.

C3 TESTING

The procedure shall be as follows:

a) Test each size of tank to the required pressure level; 25 psig (172.5 kPa) for the prefabricatedtanks with a diameter 3000 mm or less and 15 psig (103.5 kPa) for prefabricated tanks with adiameter greater than 3000 mm;

b) Allow the tank to hold the pressure for a period of 1 min;

c) Run the test using a pressure gage graduated in increments of 1 psig (6.9kpa) or less.

C4 TEST CRITERIAFailure to hold the required pressure as given in 5.2.3.3 (b) with 10% drops allowed for pressure

settlement is indication of failure.


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ANNEX D

DETERMINATION OF RESISTANCE TO LATERAL LOAD (HYDRAULIC TEST)

(Normative)

D1 SCOPE

This Annex outlines a method for testing the resistance of a non-cylindrical prefabricated tank to anapplied lateral load.

D2 PRINCIPLE

The lateral (side loading) forces on a tank due to soil in a fully or partially saturated state, togetherwith any incidental additional loading due to the presence of earth-moving equipment adjacent to thetank wall may be represented by a circumferential load applied to the wall of the tank. These forcesequate approximately to the forces applied to an empty tank held submerged in water.

The test method requires that forces due to any anchorage technique normally used with the

prefabricated tank are simulated during the test.

D3 TESTING

The test procedure shall be as follow:

a) Install the empty tank in the test pit and restrain it as necessary. If it is necessary to reproduceanchorage compression, weights shall be placed on the upper rim of the tank. Holding down thetank in a manner that does not provide any lateral stability to the tank in excess of that providedby the lid, when installed;

b) Fill the outer container with water up to the designed burial depth, including risers, of the test tank;

c) Maintain the tank under test for a minimum of 7 days.

D4 TEST CRITERIAInspection shall show that there have been no leaks and that the integrity of the tank has nopermanent damage. Inspection shall show that the deflection measured in the tank wall does notexceed the wall thickness at that point.


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ANNEX E

DETERMINATION OF WATERTIGHTNESS (LEAKAGE TEST)

(Normative)

E1 SCOPE

This Annex outlines a method of testing the watertightness of unit of prefabricated tanks.

E2 PRINCIPLE

The tank is subjected to a hydrostatic pressure head and is then examined for signs of leakage.

E3 TESTING

E3.1 Test Condit ions for Pneumatic Testing (Cylindr ical Tank)

The tank undergoes an aerostatic test at the required pressure level above ground without special

support, using a pressure gauge graduated in 0.25 psig (1.75 kPa) increments or less.


a) While the tank holding the required internal pressure level as given in 5.2.3.3 (b), coat the entiretank with a liquid composed of water and leak test fluid or detergent;

b) After coating, check the tank visually for leaks, giving special attention to tank openings.

The pressure may drop in this test as the tank makes a temperature adjustment. Do not start theleakage test until the pressure settles and the tank holds the pressure. Make adjustments to the tankpressure to maintain the required pressure during this settling period of 24 hours.

E3.2 Test Conditions for Hydrostatic Testing (Non-cylindrical Tank)

Tanks that can be stood in position without the need of support shall be placed on at least threebearing blocks. Tanks that need support in order to remain in position shall be placed on timberbearers and held in place with chocks. Horizontal tanks shall be supported sufficiently so as tocounter any bending and induced tension.

For the test, an elbow is plumbed into the outlet (temporarily). Start the test with the water level at amark about 50 mm up vertical. Measure the water needed to top tank up to that same sight mark.


c) Level the tank on the supports;

d) Fill the tank with water to the invert of the outlet pipe;

e) Allow to stand for a minimum of 4 hours;

f) Top up with water and start test observation; and

g) Observe for any leakage and count the drops per minute from any single point.

E4 TEST CRITERIAFor cylindrical tanks complete with attachments for 3000 mm diameter and less, it shall not leak atpressure level of 5 psig (34.5 kPa) and for tanks greater than 3000 mm diameter, it shall not leak atpressure level of 3 psig (20.7 kPa).

For non-cylindrical tanks it shall have no leakage and no damp patches for both FRP and HDPE tank.


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ANNEX F

DETERMINATION OF THE RESISTANCE OF A PARTITION TO A HYDROSTATIC HEAD(PUMP OUT TEST)

(Normative)

F1 SCOPE

This Annex outlines a method for testing the resistance of a tank partition to the effects of pumpingout fluid from one side of the partition.

F2 PRINCIPLES

With the fluid is removed from one side of a partitioned tank during pump-out, the partition may besubjected to a hydrostatic pressure head. This test reproduces those conditions and then checks forany signs of weaknesses or failure of the partition.

F3 TESTING

The test procedure shall be as follows:

a) Fill the tank with water up to the top of the partition or to the level of any hole through it;

b) Pump out water from one side of the partition. If the partition is situated so that there is a greaterquantity / head of water on one side as compared to the other, the water shall be pumped outfrom the side that has the least quantity / head;

c) Observe the reaction of the partition to the effect of the pump out process, and over a period of atleast 1 hour.

F4 TEST CRITERIA

The water in the tank shall be able to be pumped out without the partition collapsing or permanentlydeforming.


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ANNEX G

DETERMINATION OF THE INSTALLATION OF FITTINGS IN A SOUND AND WATERTIGHTMANNER

(Normative)

G1 SCOPE

This Annex outlines a method for testing for the installation of fittings in a sound and watertightmanner, whether the fittings are installed in the factory or on-site.

G2 PRINCIPLES

The fittings in a tank are subjected to a low hydrostatic pressure from inside the tank.

It is assumed that a fitting installation that is watertight in this situation will also be watertight againstwater ingress to the tank through the filltings.

G3 TESTING

Tanks that can be stood in position without the need of support shall be placed on at least threebearing blocks. Tanks that need support in order to remain in position shall be placed on timberbearers and held in place with chocks. Horizontal tanks shall be supported sufficiently so as tocounter any bending and induced tension.

For the test, an elbow is plumbed into the outlet (temporarily). Start the test with the water level at amark about 50 mm up vertical. Measure the water needed to top tank up to that same sight mark.

The test procedure shall be as follows:

a) Install fittings in accordance with the manufacturers instruction;

b) Seal openings in the fittings to allow water to build up behind the fitting during the test;

c) Fill the tank with water to the rim;

d) Allow the tank to stand for at least ten minutes;

e) Observe the tank and fittings for any leakage.

G4 TEST CRITERIA

As for FRP and HDPE tanks it shall have no leakage and no damp patches.


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ANNEX H

DETERMINATION OF THICKNESS (THICKNESS TEST)

(Normative)

H1 SCOPE

This Annex outlines a method for testing the thickness of structural tanks wall, end panel, partitionwall and internal components for finish product of prefabricated tank.

H2 PRINCIPLES

The tanks are subjected to non-uniform thickness during the manufacturing process and are thenexamined to ensure that each part complies with the required minimum thickness.

H3 TESTING

The minimum required wall thickness of the cylindrical tank shell at any fluid level shall be determined

by using a Fisher Scope. Vernier Calliper is use when testing the thickness of specimens which arecut out from the shell.

The testing procedure shall be carried out by measuring the thickness at certain parts the determiningcomponents of structural tanks wall, end panel, partition wall and internal components.

H4 TEST CRITERIA

The thickness of all parts measured shall comply with the minimum thickness specified in 7.1.5 and7.2.5.

Documents

Specification Package Plant-