HVAC Condensate Recovery in Girl Intermediate School

8/18/2019 HVAC Condensate Recovery in Girl Intermediate School

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CONDENSATION RECOVERY QURANIC GIRL INTERMEDIATE SCHOOL CASE STUDY, JUBAIL KINGDOM OF

SAUDI ARABIA

PREPARED BY: MUDASSAR IDRIS RAUT – LEED GREEN ASSOCIATE


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PAGE 1

1.1 ABSTRACT

The biggest reliable source of potable water in Saudi Arabia is from Desalination Watertreatment. Since Ground source water resources are very minimal due to geographical location,country largest demand depends on Desalination water from Sea. However the production cost toconvert saline water to Potable water is considerable [1.09 US$ per cubic meter] . Since water is very crucial for daily activities & converting Saline Water into potable consume ample amount ofenergy & money, it obviously increases an alarm to reduce water consumption at site & look forother replaceable derivatives which can replace Potable water intake from Municipal Bodies. TheSaudi Minister of Water & Electricity estimated that 25% of Saudi Oil & Gas Production in fiscal yr.2009 was used domestically to generate electricity & produce water, with present demand ratessuggesting that this figure will reach 50% by yr. 2030 as per research by [BELFER CENER for science

& International Affair] .

To focus on this cause Mechanical Engineering Division of Abdul Al Rahman AL NaimConsultant- Dammam has developed a conceptual design for Water Reclaim use at Quranic SchoolProject- a Royal Commissioning Project in Jubail, Kingdom Of Saudi Arabia .

1.2 BACKGROUND STUDY ON CONDENSATION

Proposed HVAC system designed is of Chilled Water System where in there are 5 No’s AirHandling Unit used in Girl Intermediate School & 2 No’s Air Cooled Chillers. Since this schools arelocated in Jubail where there is enough amount of humidity present in air, the water present canbe used after condensation. As per ASHRAE [American Society Heating Refrigeration & AirConditioning Engineers] standards school requires larger amount of outside air to main insideschool environment healthy. Now this outside brings large load on Air Handlers Cooling Coils inturn increasing the amount of moist air passing through these Coils. As this air passes through

these coil, temperature of air drops as a result the air can no longer holds the amount of moistureas it was holding when it was relatively hot. This process can easily be understood in Psychometricanalysis of Air handling units. As a result the moisture present in moist air drops off & this entireprocess is called Condensation. Note that not all the moisture present in moist air drops as thereis still resultant moisture present in air leaving the cooling coil. The exact theoretical amount ofmoisture required depends on Indoor Desired room condition: - In this case we are maintaining50% relative humidity as commanded by ASHRAE standards for school project & it also complying with our client Royal Commission Design basis Reports [DBR]. This process is explained in belowfig. 1.1

http://belfercenter.hks.harvard.edu/files/Kajenthira-Anadon-Siddiqi%20--%20Wastewater%20Reuse%20in%20Saudi%20Arabia.pdfhttp://belfercenter.hks.harvard.edu/files/Kajenthira-Anadon-Siddiqi%20--%20Wastewater%20Reuse%20in%20Saudi%20Arabia.pdfhttp://belfercenter.hks.harvard.edu/files/Kajenthira-Anadon-Siddiqi%20--%20Wastewater%20Reuse%20in%20Saudi%20Arabia.pdfhttp://belfercenter.hks.harvard.edu/files/Kajenthira-Anadon-Siddiqi%20--%20Wastewater%20Reuse%20in%20Saudi%20Arabia.pdfhttp://belfercenter.hks.harvard.edu/files/Kajenthira-Anadon-Siddiqi%20--%20Wastewater%20Reuse%20in%20Saudi%20Arabia.pdfhttp://belfercenter.hks.harvard.edu/files/Kajenthira-Anadon-Siddiqi%20--%20Wastewater%20Reuse%20in%20Saudi%20Arabia.pdfhttp://belfercenter.hks.harvard.edu/files/Kajenthira-Anadon-Siddiqi%20--%20Wastewater%20Reuse%20in%20Saudi%20Arabia.pdfhttp://belfercenter.hks.harvard.edu/files/Kajenthira-Anadon-Siddiqi%20--%20Wastewater%20Reuse%20in%20Saudi%20Arabia.pdf


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PAGE 2

1.3 WHAT IS CONDENSATE WATER?

Condensate is a byproduct generated during Air Conditioning process which isusually wasted & drained to sewer. Condensate is generated in the same manner as distilled water, which has a slightly acidic pH value around 5.8 , as compared to a neutral pH value of 7.0,and contains no minerals. However, unlike distilled water, condensate is subject to environmentalcontamination during the process of collection and transport. Microorganisms (e.g., bacteria and viruses) suspended in air drawn from inside and/or outside the building (i.e., return air and/oroutside air) through the Air Handling Unit (AHU) can collect on the cooling coils with the moisture when condensate is formed (see Fig 1.1 for a schematic of an AHU). In addition, being slightly acidic,

condensate tends to react with materials with which it comes in contact. Such reactions can raisethe pH value of condensate. Any molecules or particulates the condensate picks up duringformation or along its flow path can be referred to as a contaminant and must be considered whenmaking treatment decisions.

Fig: 1.1


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PAGE 3

1.4 ACCUSTOMED CONDENSATE PRACTICESLargely the condensate collected is discarded through various drain points & dumped into

normal sewers. This not only waste this high valuable clean Distilled water but also adds loads inSewer Treatment Plant on Local municipal bodies thus increasing additional Energy & Cost factorsto the Government. This not only burden the Government organization but also results inadditional GHG [Greenhouse Gas] emission into environment.

Fig: 1.2


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PAGE 4

1.5 CONDENSATE WATER APPLICATION

Can be used in 3 main Domain.

1. COOLING TOWERS.2. TOILET FLUSHING.3. LANDSCAPE IRRIGATION & HARDSCAPE CLEANING.

The most effective use of condensate water collected from commercial or industrialbuildings is for makeup water in cooling towers. This is because the pure and cool condensate water

dilutes the sediment buildup in cooling towers (the sediment is left behind during the evaporativecooling process), increases the efficiency of the cooling towers by virtue of its relatively cooltemperature, provides the most water in hot and humid conditions when makeup water for thecooling towers is most needed, and requires no additional storage or treatment.

Other common uses of condensate include toilet flushing, irrigation, ornamental water features,and process water, such as that used in manufacturing. Designing for these uses requires a waterbudget to determine how much water is produced (supplied) versus how much is required(demanded) for the intended purpose. Storage is required if the water produced cannot beimmediately used for its intended purpose. This is the case with most applications except forcooling towers and perhaps some process water and irrigation applications, depending on exactneeds. Treatment in the form of filtration and disinfection is used to raise the quality of the waterfor its intended application. Applications in which reclaimed water could conceivably come incontact with human skin or be ingested require the highest-quality water. In all cases, a well-designed and well-maintained HVAC system is critical to the production of condensate that is freeof microbial buildup or other contaminants

Except for Cooling Tower usage, local codes or AHJ Authority Having Jurisdiction & InternationalCode like IPC, IBC should be followed if condensate water is to be used for application involving

direct human contact or some time ingestion. Also a detail water report must be conducted onmonthly basis to study the acidic nature or micro Organism growth of condensate collected forother uses. Because this acidic nature may harm the Toilet ceramic if repeatedly used or it mayharm landscape, Lawn Sprinklers, Drip irrigation pipes, Pumps, Fountains etc. For best result astrict maintenance of AHU equipment is required on weekly/monthly basis from Maintenance &Operation Contractor.

BECAUSE THERE ARE NO COOLING TOWERS IN QURANIC PROJECT, OPTION-2 & OPTION-3 ARE LEFT TO BE IMPLEMENTED. HOWEVER PROPOSED CONCEPT IN THIS REPORT ISOPTION-2 i.e TOILET FLUSHING


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1.6 HOW MUCH CONDENSATE WATER CAN QURANICINTERMEDIATE SCHOOL GIVE?

There are 5 No’s AHU in Quranic Girl Intermediate School & condensate gen erated inGallons by these AHU’ S are given in below Table 1.1.

There are various technique to capture condensate Flow Volume & Engineers & researchers havedeveloped certain Thumb rules even based on Tonnage & Sq Ft Area to be Air Conditioned.

However we have captured theoretical data from HAP [Hourly Analysis Program] Software basedon thermodynamic relation below.

QC= Qa X DENSITY X (W1-W2) X 0.45 X 0.2641 X 60-----

Where,

QC – Gallons/Hr. of Condensate.

Qa = Air Flow rate of mixed air [Return + Outdoor] in CFM

Density - Stds Density of Air = 0.075 lb/ft 3 at atmospheric Pressure.

W1 - Specific humidity of Mix Air Entering Cooling Coil.

W2 – Specific humidity of Cool Air Leaving Cooling Coil.

& 0.45, 0.2641 & 60 are conversion factors to be used to get values in Gallon/Hr.


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AHU-01 AHU-02 AHU-03 AHU-04 AHU-05

JAN 2,769 3,028 3,137 3,151 2,073

FEB 4,789 6,900 6,051 6,227 4,224

MAR 4,194 5,674 5,942 5,939 3,839

APR 4,103 5,743 6,010 5,969 3,756

MAY 5,072 7,837 7,977 7,761 4,745

JUN 6,047 9,502 9,926 9,597 5,794

JUL 1,373 2,158 2,256 2,182 1,317

AUG 6,007 9,468 9,922 9,612 5,787

SEP 3,445 5,266 5,523 5,470 3,273

OCT 6,425 9,388 9,823 9,134 5,990

NOV 5,890 8,042 8,390 8,457 5,422

DEC 2,515 3,034 3,147 3,275 2,212TOTAL

GALLONS/YR BYAHU

52,629 76,039 78,104 76,772 48,431

TOTALGALLONS/YR BYENTIRE SCHOOL

331,977 GALLONS/YR

Table: 1.1


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1.7 CONDENSATE CALCULATION PROCEDURE

Temperature Simulation file of Jubail is recorded from HAP file. The hottest day in particularmonth is recorded for which the condensation is calculated. The Maximum & minimum Dry Bulbtemperature is recorded from HAP file for which W1 & W2 is recorded. Also in spite of recording24 hrs. data for entire day only 13 hrs.[From 5 AM to 5 PM] data is recorded for that particularhottest day in a particular month. 13 hrs. data is then added to get daily data & finally this Hottestday data is multiplied with 70% diversity factor assuming all the condensate generated forremaining days will always generate less amount of condensate. Also it is assume that each monthhave 30 days immaterial of JFMAMJJASOND series. This all assumption are just for ease incalculation as hourly condensate generated for all 365 days will take ample amount of time &perhaps the exact & correlated values will have minimal variations.

W1 & W2 is recorded for every 13 hr. from HAP Psychometric Analysis procedures which showsevery 13 hrs. in every single month. Based on these value & Air flow rate of particular AHU the finalQc value is recorded for every Single hours in those 13 hrs. study. Then all 13 hrs. resulted are

summoned up to get final day value of condensate on that particular day.

Fig: 1.3


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Sample Calculation for January month for AHU-3 is as shown Below in Table-1.2

TIME W1 @ TM W2 @ T0 LPM GPM GPH GPD MONTHLY

JAN

500 0.00864 0.00769 0.52 0.14 8.29

209.14 3137.17

600 0.01105 0.00879 1.24 0.33 19.73

700 0.01105 0.00874 1.27 0.34 20.16

800 0.01107 0.00877 1.27 0.33 20.08

900 0.01104 0.00869 1.29 0.34 20.51

1000 0.01104 0.00869 1.29 0.34 20.51

1100 0.01102 0.00864 1.31 0.35 20.77

1200 0.01103 0.00863 1.32 0.35 20.95

1300 0.01101 0.0086 1.33 0.35 21.04

1400 0.011 0.0086 1.32 0.35 20.95

1500 0.00864 0.00764 0.55 0.15 8.73

1600 0.00807 0.00763 0.24 0.06 3.84

1700 0.00806 0.00765 0.23 0.06 3.58

LPM- Liters Per Minute

GPM – Gallon Per MinuteGPH- Gallon Per Hour

GPD - Gallon Per Day

To Get Monthly data, peak load Condensation value is multiplied with Occupied Days of thatparticular month [In above case January is noted (See Section 1.8).

In a similar way rest of the month data were recorded to get the results of yearly package. This datacapturing is done form all 5 No’s AHU to get the condensate generated for Entire Quranic

Intermediate School. Now as depicted from above calculation & Table-1.1 we have achieved 331,977Gallons of Condensate.

Note that this condensate value is only theoretical figure & actual value in practice may below or more than this. So in order to get full proof value we have assume 50% diversity factor onthis overall value as we cannot ensure that 441,000 Gallons of condensate generated is actuallyfeasible at site. This final assumption is due below discussed reasons.

1. Nature is highly unpredicted as we cannot ascertain the values of Specific humidity W1 & W2 we have entered from HAP analysis is exactly possible at site.

Table: 1.2


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2. The above data is when the building is occupied on full load & all Chillers are running onpeak Load. But this usually happens for only small amount of time & most of the time thebuilding is HVAC system is not running on full load.

3. AHU cooling coils must be perfectly clean & well maintained through the year as we cannot

guarantee the Exact Condensate generated with Poor maintained Cooling Coil.

Moreover under worst case scenario even if we fail to get enough condensate, the proposed designsystem by ACE Consultant is flexible enough to take in account Potable water as a back water toflush the toilets. So the proposed design ensures that Human Comfort will not be disturbed byimplanting Condensate Water system for water flushing. So for Royal Commission it’s a Win -Winsituation where in they can not only save Water used at site but also end up in paying Less Water& Tax to Govt municipal Bodies.

Fig-1.4 shows a comparison between theoretical & diversified Condensate values.50% diversity is just a factor of safety to cushion our design & real-time values at site may exceed this diversityfactor.

7,079

14,095 12,794 12,79116,696

20,433

4,643

20,398

11,488

20,38018,100

7,091

14,158

28,191

25,588 25,582

33,393

40,866

9,286

40,795

22,977

40,759

36,200

14,182

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC

G A L L O

N S

MONTHS

HVAC CONDENSATION COMPARISION BETWEEN THEOROTICAL &50% DIVERSITY FOR QURANIC GIRL INTERMEDIATE SCHOOL

Fig: 1.4


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1.8 SCHOOL HOLIDAYSSEP – 9 TO SEP – 17---------EID AL ADHA HOLIDAYS

DEC-16 TO JAN- 7----------WINTER BREAKMARCH – 24 TO APRIL – 8-----SPRING BREAK

JUNE – 20 TO JULY – 29 ---------SUMMER BREAK

Above holiday structure is taken from KAUST[King Abdulla University of Science & Technology-Thuwal]. Although holiday structure of University is followed, this holiday structure is subjectedto change as per Royal Commission School guidelines.

For all these holidays, school is considered to be completely shut down where in there is noHVAC Equipment running & also there is no Occupant load in School to use Toilet Flushing. Alsoit is assume that a month will have only 22 days of occupancy excluding all weekend.

Note that for this reason among 3 Basic uses of condensate water , we have opted to use condensate water for Toilet Flushing because even if school is shut down we need water to maintain Landscapebut on contrary we don’t need water to flush toilets as there is no Occupant Load in toilets during vacation period.

A detailed graphical representation will help in explaining the Holiday Structure & OccupancyLoad. It is quite important to note at this stage, for Water budget estimating for flushing, we willuse this same occupancy load to balance demand water for Toilet flushing with producedcondensate water.


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1.9 WATER BUDGET

One of the prime motive to develop water budget is to estimate the Water demand used forflushing of Water Closet. We are using highly efficient Toilets in this school with flush rate rangingfrom 0.8-1.28 Gallons/Flush.

Quranic Girl Intermediate School is divided into 5 Zones for both HVAC & plumbingCalculations. The detail Sub-Division of these zone is shown below in figure-1.51

Fig: 1.5


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Total number of Water Closet in all Zones & their respective demand Flow volume is as shown inTable-1.31 & Total Flushing Demand for Entire School/monthly is shown in Table-1.32

Fig: 1.51


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ZONENO'S OFWATERCLOSET

GALLONS/FLUSH

NO OF OCCUPANTFlush/

Person/DayFlush/Day/

ZoneGallons/Day/

Zone

A 5 0.8 20 3 60 48

B 7 0.8 246 3 738 590

C 7 0.8 246 3 738 590

D 7 0.8 225 3 675 540

E 3 0.8 20 3 60 48

MONTHNO OFOCCUPIEDDAYS

Gallons/Month

ZONE-A

Gallons/Month

ZONE-B

Gallons/Month

ZONE-C

Gallons/Month

ZONE-D

Gallons/Month

ZONE-E

JAN 15 720 8,850 8,850 8,100 720

FEB 22 1,056 12,980 12,980 11,880 1,056

MAR 15 720 8,850 8,850 8,100 720

APR 14 672 8,260 8,260 7,560 672

MAY 22 1,056 12,980 12,980 11,880 1,056

JUN 22 1,056 12,980 12,980 11,880 1,056

JUL 5 240 2,950 2,950 2,700 240

AUG 22 1,056 12,980 12,980 11,880 1,056

SEP 11 528 6,490 6,490 5,940 528

OCT 22 1,056 12,980 12,980 11,880 1,056

NOV 22 1,056 12,980 12,980 11,880 1,056

DEC 12 576 7,080 7,080 6,480 576

TOTAL GALLONS/YR/

ZONE 9,792 120,360 120,360 110,160 9,792

TOTAL GALLONS/YRFOR ENTIRE SCHOOL 370,464

Table: 1.31

Table: 1.32


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1.91 DETAIL WATER BUDGET CALCULATION OF ZONE- A FOR JANUARY MONTH

Assuming 3 flushes/day/student or staff in Girl Intermediate SchoolToilet Flush & Gallons used in ZONE-A:

No of occupant = 20

Flush/person/day = 3

Flush/Day/Zone = 20 x 3 = 60

Gallons/Day = 60 x 0.8 = 48

No of Occupied days in January Month = 15 Days

Total Demand Gallons/month = 15 x 48 = 720 Gallons-----------A

Available Gallons of Condensate Generated in January month for this Zone

2769 Gallons-----------------B

Assuming 50% diversity factor as discussed above in section 1.7

Total Supply Condensate = 2769 x 0.5 = 1385---------------C

[Please read Point 1,2,3 in section 1.7 to know more about this Diversity Factor]

From Equ-A & Equ-C it’s clear that Condensate generated is enough to take all the flushesassumed & still 1385-720= 665 Gallons will be left unused for any uncertain demand.

This explains that condensate generated in January Month for Zone-A in GIRL

INTERMEDIATE SCHOOL IS SUFFICIENT TO FLUSH THESE TOILETS

1.92 DETAIL WATER BUDGET CALCULATION OF ZONE-B FOR JANUARY MONTH

Assuming 3 flushes/day/student or staff in Girl Intermediate School

Toilet Flush & Gallons used in ZONE-B:

No of occupant = 246


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Gallons/Day = 738 x 0.8 = 591




3028 Gallons-----------------B




From Equ-A & Equ- C it’s clear that Condensate generated is not enough to take all theflushes assumed & still 8856-1328= 7528 Gallons will be additional demand.

This explains that condensate generated in January Month for Zone-B in GIRLINTERMEDIATE SCHOOL IS NOT SUFFICIENT TO FLUSH THESE TOILETS

1.93 DETAIL WATER BUDGET CALCULATION OF ZONE-C FOR JANUARY MONTH


Toilet Flush & Gallons used in ZONE-C:No of occupant = 246



Gallons/Day = 738 x 0.8 = 591




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3137 Gallons-----------------B




From Equ-A & Equ- C it’s clear that Condensate generated is not enough to take all theflushes assumed & still 8856-1569= 7287 Gallons will be additional demand.

This explains that condensate generated in January Month for Zone-C in GIRLINTERMEDIATE SCHOOL IS NOT SUFFICIENT TO FLUSH THESE TOILETS

1.94 DETAIL WATER BUDGET CALCULATION OF ZONE-D FOR JANUARY MONTH


Toilet Flush & Gallons used in ZONE-D:

No of occupant = 225



Gallons/Day = 675 x 0.8 = 540

No of Occupied days in January Month = 15 DaysTotal Demand Gallons/month = 15 x 540 = 8100 Gallons-----------A


3151 Gallons-----------------B


Total Supply Condensate = 3151 x 0.5 = 1575.5---------------C



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From Equ-A & Equ- C it’s clear that Condensate generated is not enough to take al l theflushes assumed & still 8100-1575.5= 6524.5 Gallons will be additional demand.

This explains that condensate generated in January Month for Zone-D in GIRLINTERMEDIATE SCHOOL IS NOT SUFFICIENT TO FLUSH THESE TOILETS

1.95 DETAIL WATER BUDGET CALCULATION OF ZONE-E FOR JANUARY MONTH


Toilet Flush & Gallons used in ZONE-E:

No of occupant = 20



Gallons/Day = 60 x 0.8 = 48




2073 Gallons-----------------B




From Equ-A & Equ- C it’s clear that Condensate generated is enough to take all the flushesassumed & still 1037-720= 317 Gallons will be left unused for any uncertain demand.


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This explains that condensate generated in January Month for Zone-E in GIRLINTERMEDIATE SCHOOL IS SUFFICIENT TO FLUSH THESE TOILETS

CONCLUSION: CONDENSATE GENERATED IN ZONE-A & ZONE-B IS SUFFICIENT TOCOVER ALL THE FLUSHING DEMANDS DUE TO LOW OCCUPANT LOAD BUTCONDENSATE GENERATED IN ZONE-B,C,D IS NOT SUFFICIENT TO MEET THE FLUSHINGDEMAND DUE TO HIGH OCCUPANT LOAD

The Demand curve vs Condensate to support flushing Demand for all the zone is shown

below in Fig:1.6

720

1,056

720 672

1,056 1,056

240

1,056

528

1,056 1,056

576

1038

1796

1573 1539

1902

2268

515

2253

1292

2409

2209

943

0

500

1,000

1,500

2,000

2,500

3,000


G A L L O N S

MONTH

ZONE-A


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PAGE 19

8,850

12,980

8,8508,260

12,980 12,980

2,950

12,980

6,490

12,980 12,980

7,080

1,514

3,4502,837 2,871

3,9194,751

1,079

4,734

2,633

4,6944,021

1,517

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000


G A L L O N S

MONTH

ZONE-B

8,850

12,980

8,8508,260

12,980 12,980

2,950

12,980

6,490

12,980 12,980

7,080

1,569

3,026 2,971 3,005

3,989

4,963

1,128

4,961

2,761

4,9114,195

1,573

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000


G A L L O N S

MONTH

ZONE-CFig: 1.6


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PAGE 20

8,100

11,880

8,1007,560

11,880 11,880

2,700

11,880

5,940

11,880 11,880

6,480

1,575

3,114 2,970 2,9853,881

4,798

1,091

4,806

2,735

4,567 4,228

1,637

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000


G A L L O N S

MONTH

ZONE-D

Fig: 1.6


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PAGE 21

From above graphical representation it’s clear that for Zone-A & Zone-E; condensate is available inexcess amount & same can be pumped to Zone – B, C, and D as required as condensate in theseZone is not sufficient due to heavy Occupant Load. This can be well understood with Fig 1.7 whichshows condensate deficit in Zone-B-C-D.

As Zone-B is close to Zone-A, excess condensate from Zone-A can be used in Zone-B. In a similar way excess condensate from Zone-E can be used in Zone-D. This is explained in Table: 1.4 & Fig1.7.

This will ensure that the excess of Condensate in Zone-A, E is not wasted & in-turn used in otherzone to meet the motive of water conservation

720

1,056

720 672

1,056 1,056

240

1,056

528

1,056 1,056

576

1,037

2,1121,920 1,878

2,373

2,897

658

2,893

1,636

2,9952,711

1,106

0

500

1,000

1,500

2,000

2,500

3,000

3,500


G A L L O N S

MONTH

ZONE-E

Fig: 1.6


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EXCESSCONDENSATE

IN ZONE-A[X]

ORIGINALCONDENSATE

IN ZONE-B[Y]

COMPENSATEDCONDENSATE

OF ZONE-B[Z=X+Y]

EXCESSCONDENSATE

IN ZONE-E[M]

ORIGINALCONDENSATE

IN ZONE-D[N]

COMPENSATEDCONDENSATE

OF ZONE-D[O=M+N]

JAN 665 1,514 2,179 317 1,575 1,892FEB 1,338 3,450 4,788 1,056 3,114 4,170

MAR 1,377 2,837 4,214 1,200 2,970 4,169APR 1,380 2,871 4,251 1,206 2,985 4,191MAY 1,480 3,919 5,399 1,317 3,881 5,197JUN 1,968 4,751 6,719 1,841 4,798 6,639JUL 447 1,079 1,526 418 1,091 1,509

AUG 1,947 4,734 6,681 1,837 4,806 6,643SEP 1,195 2,633 3,828 1,108 2,735 3,843OCT 2,156 4,694 6,850 1,939 4,567 6,506

NOV 1,889 4,021 5,910 1,655 4,228 5,883DEC 682 1,517 2,199 530 1,637 2,167

8,100

11,880

8,1007,560

11,880 11,880

2,700

11,880

5,940

11,880 11,880

6,480

1,575

3,114 2,970 2,9853,881

4,798

1,091

4,806

2,735

4,567 4,228

1,6371,892

4,170 4,169 4,1915,197

6,639

1,509

6,643

3,843

6,5065,883

2,167

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000


G A L L O N S

MONTH

COMPENSATED CONDENSATE ZONE-D

Table: 1.4

Fig: 1.7


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PAGE 23

At this stage we can build the condensate use of Entire School with the total demand. This isexplained with Fig: 1.8 below.

8,850

12,980

8,8508,260

12,980 12,980

2,950

12,980

6,490

12,980 12,980

7,080

1,514

3,4502,837 2,871

3,9194,751

1,079

4,734

2,633

4,6944,021

1,5172,179

4,7884,214 4,251

5,399

6,719

1,526

6,681

3,828

6,8505,910

2,199

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000


G A L L O N S

MONTH

COMPENSATED CONDENSATE ZONE-B

27,240

39,952

27,24025,424

39,952 39,952

9,080

39,952

19,976

39,952 39,952

21,792

7,079

14,095 12,794 12,79116,696

20,433

4,643

20,398

11,488

20,38018,100

7,091

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

45,000


G A L L O N S

MONTH

DEMAND VS CONDENSATE IN ENTIRE GIRL INTERMEDIATESCHOOL

Fig: 1.7

Fig: 1.8


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PAGE 24

2.0 CONCLUSION AFTER WATER BUDGETTING.

After detailed Water Budget study, it can be concluded that if we can use

1. 100% Condensate water for Toilet Flushing we can save up to 331,977 Gallons/Yr. of Potable water.

2. 50% Condensate water for Toilet Flushing we can save up to 165,989 Gallons/Yr. of Potable water.

In addition it’s important to note that these thousands of Gallons is avoided both at input stage &

at Exit stage of School premises. This means W e don’t need to pump this much of saved Gallons of water from Marafiq Municipal Govt

Organization which not only guarantee reduced Water charges to Quranic Project but alsoreduces Water Desalination requirement at these many Gallons of water thus helping Saudi Arabia energy demand crisis which is discussed in Section 1.1.

We can avoid draining these many Gallons of water into Local Sewer which could have againincreased Water Treatment Cost of these many Gallons.

Lease but not less, this condensate Reclaim may look like tiny save of water when compared withOverall Mutrafiah Quranic School Demand but still this little saving of water can assureSustainability & Commitment to Environment.

2.1 COST ANALYSIS A. SYSTEM WITHOUT CONDENSATE

Let us now analysis how much savings we get in terms of money. Clearly there is 370,464 Gallonsor 1403 Cu meter of annual water demand alone for flushing. If it happens to use only Potable wateralone for flushing, it would cost 8,414 SAR/Annual as per Marafiq Water Tariff in Table 1.5.


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PAGE 25

WITHOUT CONDENSATE

MONTH

DemandGallons/MonthEntireSchool

Potable WaterDemand CU

METER/MONTHENTIRE SCHOOL

SAR[300 ABOVE]

CU.M6 SAR

JAN 27,240 103 619

FEB 39,952 151 907

MAR 27,240 103 619

APR 25,424 96 577

MAY 39,952 151 907

JUN 39,952 151 907

JUL 9,080 34 206AUG 39,952 151 907

SEP 19,976 76 454

OCT 39,952 151 907

NOV 39,952 151 907

DEC 21,792 82 495TOTAL 370,464 1,402 8,414

Note: Water tariff are standards water tariff takenexclusively for Royal Commissioning Projects considering

water consumption are always above 300 CuMeter/Monthly

8414 SAR annual cost will be of no comparison if it needs to be compared with CondensateRecovery System Initial Cost. Because in Saudi Arabia water is charged at very low compared

with a price its produced at Desalination Plants. This extra amount Govt is subsidizing from overexempting on its citizen & delivering water at very low tariff. This is why we cannot get a Pay Backperiod for our Condensate Recovery System with actual Marafiq Tariff as this system obviously will exceed 8414 SAR overall Cost even for a Payback Period of 5 yrs.

So to get a clear picture let us bring additional Cost for Sea Water Desalination & Water Treatmentto be done to this 1403 Cu meter water, so that this water to be eligible for Potable Water.

Note that this additional cost Saudi Govt is paying for every Cu Meter to convert Sea Water intoPotable water & treat Sewer after being used.

Table: 1.5


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PAGE 26

A Potable Water Cost: 8414 SAR--------------------------A

B. Cost of Desalination=4.08 SAR/Cu Meter [1.09 US$/CU Meter]

Total Cost = 4.08 x 1403 = 5724 SAR ------------------------B

C. Cost Of Water Treatment = 7.45 SAR/CU Meter [1.98 US$/CU Meter]

Total Cost = 7.45 x 1403 = 10,452 SAR-------------------------C

TOTAL COST = A +B + C = 8414+5724+10,452 = 24,590 SAR /Annual.

B. SYSTEM WITH CONDENSATE

Assuming 50% condensation, we noticed that we have 165,989 Gallons ofCondensate. Table 1.6. & additional we need 774 Cu Meter of potable water

for complete flushing. This comes with an expense of 4644 SAR/Annually. A Potable Water Cost: 4644 SAR--------------------------A

B. Cost of Desalination=4.08 SAR/Cu Meter [1.09 US$/CU Meter]

Total Cost = 4.08 x 774 = 3158 SAR ------------------------B

C. Cost Of Water Treatment = 7.45 SAR/CU Meter [1.98 US$/CU Meter]

Total Cost = 7.45 x 774 = 5766 SAR-------------------------C

TOTAL COST = A+B + C = 4644+3158+5766 = 13,568 SAR /Annual.

Table: 1.5


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PAGE 27

TOTAL COST SAVINGS: 24,590 – 13,568 = 11,022 SAR/ANNUALLY

TOTAL WATER SAVINGS: = 165,989 GALLONS/ANNUALLY

WITH CONDENSATE

MONTH

DemandGallons/MonthEntireSchool

Gallons OF 50%Condensate/

MonthEntire School

POTABLEWATER CU

METER/MONTHENTIRE SCHOOL

SAR[300

ABOVE]CU.M6 SAR

JAN 27,240 7,079 76 458

FEB 39,952 14,095 98 587

MAR 27,240 12,794 55 328

APR 25,424 12,791 48 287

MAY 39,952 16,696 88 528

JUN 39,952 20,433 74 443

JUL 9,080 4,643 17 101

AUG 39,952 20,398 74 444

SEP 19,976 11,488 32 193

OCT 39,952 20,380 74 445

NOV 39,952 18,100 83 496DEC 21,792 7,091 56 334

TOTAL 370,464 165,989 774 4,644Note: Water tariff are standards water tariff taken exclusively for Royal

Commissioning Projects considering water consumption are alwaysabove 300 Cu Meter/Monthly

CONDENSATE RECOVERY SYSTEM COST:

PAYBACK PERIOD:

Table: 1.6


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PAGE 28

2.2 BASIC DESIGN

Concept of Initial Design is made simple with the use of 2 No’s Condensation Tank. Exacttank sizing & Pipe Sizing is not done at this stage of design as the whole Condensate ReclaimEngineering need prior approval from Royal Commissioning.

2 tank concept is used to overcome all the unpredicted condensation thus adding moresafety & reliability. Tank-1 is designed to hold 1 week condensate & Tank-2 is designed to dependon Tank-1 to meet the Flushing demand. Also 2 or more Zones can be combined to use this DualDesign concept. Tank-1 can hold 1 week condensate demand to feed the Flushing requirement inSchool. Float switch installed in Tank-2 is preset between Upper & Lower layer; where in lowerlayer is set for at least 1 day Flushing Demand of Zones involved in that design

Fig-1.9 explain the schematic layout of typical Condensate Collection System.

NOTE:

1. To capture the flow of condensate Water Metering may be required. This will bemandate if any building is applying for LEED Certification; as per LEED V4 is concernedBuilding Level Water Metering is both Pre-requisite & Credit. However in this proposeddesigned we have not included any Water meters since Quranic Project didn’t appliedfor any LEED certification.

2.

It will be an optional step to use water treatment depending on the pH value of thecondensate. If pH reduces drastically then a chlorine Dosing tank along with pH sensorinstalled & interlocked with dosing tank may be used. It all depends on pH value ofcondensate at the time of Commissioning Phase.

SEQUENCE OF OPERATION

Float switch in Tank-2 after reaching at lower level sends a control signal to Motorized Valve-1 through Control Logic Panel-1[CP-1]. This will activate the valve to open & condensatecollected in Tank 1 reaches Tank-2. This flow is sensed by Flow-Switch installed & this in turn givesa Control Logic Signal to Motorized valve-2 to get closed.

If the Motorized Valve-1 open & there is no condensate in Tank 1; then in this case the Flow Switch will send signal to Motorized Valve-2 to open through Cp-2. This will activate Potable Water Feedin Tank-1 & once upper level is reached Potable water is stopped.

CP-1 & CP-2 are interlocked to control Potable Water feeding.


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PAGE 29

2.2 CONDENSATE RECOVERY & GREEN PLUMBINGMECHANICAL CODE.

Because condensate is onsite Water recovered water we need to follow extra code apart fromusual IPC/ASPE Standards & Code. AS a practice we have followed [IAPMO] Green PlumbingMechanical Code Supplement 2012 . This code help is additional safety & further design &Commissioning input that must be adhered in addition to IPC Code.

Fig: 1.9


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PAGE 30

Fig 503.9 is a reference from Sec: 503.7 explaining the signage required in Reclaimed Waterservices. As far as Water quality is concerned of recovered Condensate water , Section: 504.10DESIGN & INSTALLATION direct AHJ [Authority Having Jurisdiction] or local code for furthertreatment before any end use on Toilet flushing.

2.3 INSTALLED SNAPS FOR REFRENCE

REFERENCE: Review of Saudi Arabia Municipal Water Tarif- Omar K M Ouda, Department of Civil

Engineer, Prince Muhammad Bin Fahd University, Al Khobar, Kingdom Of Saudi Arabia. Hourly Analysis Program Software Specific Humidity results for Quranic Girl Intermediate

School- Mutrafiah Project, Al Jubail- Kingdom of Saudi Arabia Designed by Abdul Rahman AL Naim Consultant Engineers- Dammam, Kingdom Of Saudi Arabia.

San Antonio- United States of America- User Manual for Condensate Collection & UseManual for Commercial Buildings.

ASHRAE Journal on Condensate Recovery System by Karen Guz Vol 47, no-6 Published on June 2005.


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White paper by Belfer Center for Science & international Affairs on Waste Water Reuse inSaudi Arabia by Arani, Laura Diaz & Afreen Siddique.

Engineers Newsletter by TRANE Vol 36-4 for FAQ on LEED & HVAC design forsustainability.

2012 Green Plumbing & Mechanical Code Supplement; Second Edition. American Society of Plumbing Engineer; Vol-2 for Water Purification stds & treatment.

Documents

HVAC Condensate Recovery in Girl Intermediate School