Water Loss Management In Distribution Pipe Basic Knowledge

Transcription

1 Water Loss Management In Distribution Pipe Basic Knowledge

2 1. Water Balance IWA concept 2. Water Loss Indicator 3. Reduce Non Revenue water Concept

3 Why water loss is Important? - Lack of water resource - Save operating cost - Save energy for pumping - Increase Level of operation pressure - Reliability in distribution pipe system - Excellent service quality

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5 Background Leak Can t record unavoidable Main Leak Can detect

6 Water Balance IWA concept System Input volume SIV (100%) Authorised Consumption (75.13%) Water Losses UFW (24.87%) Bill Authorised Unbill Authorised Apparent Losses 62.1 (3.6%) Real Losses (CARL) (21.2%) Billed Metered Cons (74.74%) Billed Unmetered Cons 0 (0%) Unbilled Metered Cons 0(0%) Unbilled Unmetered Cons 6.7 (0.39%) Unauthorized Cons 17.2 (1%) Customer Meter Inaccuracies & Data Handling Error 44.9 (2.6%) Leakage on Trunk Mains Leakage on Distribution Mains Leakage on Service Connections up to metering point Show each component of water RW (74.74%) Non Revenue Water (NRW) (25.26%)

7 Component of Authorized consumption Authorized Consumption Billed Meter consumption = customer pay from billing system Customer use Blow off / Fire Hydrant Use in construction Unbilled consumption = Amount water that can authorized from evaluate Use in operation, Utility Blow off / Fire Hydrant Use in construction/repair

8 Component of Water loss Apparent Loss / Commercial Loss Water loss Illegal in consumption Inaccuracy of Meter Physical loss / Real loss Leakage in pipe Unbilled Authoried NRW

9 WB Advantage of using Water Balance - Show all components of water - Clearly, Classify - Low estimate Data / Realizable

10 WB Disadvantage of using Water Balanc - Lack of Data / 1 Billing cycle for Water balance - Customer billing cycle not finish in same time - All of master meter must operation all time Error occur when estimate data

11 Water loss Indicator UFW unaccounted of water Volume / Percentage NRW non revenue water Volume / Percentage ILI Infrastructure leakage index Non Unit

12 Water Audit Concept Top Down Water balance Collect SIV, Componet each water Loss Indicator Bottom - Up Use MNF to evaluate Amount of loss

13 Minimum Night Flow MNF is the Minimum Flow rate at Night time Assumption 1.Leakage all time 2. At night time Consumption is very low 3. MNF is nearless Leak flow 4. Use Daily MNF for estimate Water loss

14 %UFW %UFW = %(SIV Authorized consumption)/ SIV Advance - Easy for Calculate - Easy for collecting data - Easy for monitoring Trend In same area Disadvantage - Error if over estimate Amount of water which Unmetered - Can not compare in Some area

15 Non revenue water %NRW = %(SIV- Billed consumption) /SIV Advantage - Easy - Refer to Revenue Note - NRW > UFW

16 Example Calculate of UFW,NRW Authorized Billed 3000 Billed Metered Cons 2500 Billed Unmetered Cons 500 RW? 3000 (60%) 3500 (70%) Unbilled 500 Unbilled Metered Cons 200 Unbilled Unmetered Cons 300 SIV 5000 (100%) Water Losses UFW?? 1500 (30%) Apparent Losses 250 Real Losses (CARL) Unauthorized Cons 100 Customer Meter Inaccuracies & Data Handling Error 150 Leakage on Trunk Mains 500 Leakage on Distribution Mains 500 Non Revenue Water (NRW)?? 2000 (40%) % Leakage on Service Connections up to metering point 250

17 How to Ranking Area Area 1 Area 3 15% 22% 300 m m 3 Area กม. 38% 250 กม. 270 m 3 Area 4 Area 6 32% 180 กม. 43% 350 m m 3 Area กม. 7% 300 กม. 250 m 3 High 700 กม. Area 7 32% Water loss Volume loss 700 m กม. %NRW 6 2 Pipe length Volume 7 6 Length Low 5 3 2

18 Key factor independent to water loss Pipe length Water loss Pressure Sevice connection

19 ILI infrastructure leakage index ILI = CARL / UARL Advantage - Use variable of factor - Use for Ranking Priority - Can compare for every area Disadvantage - Many source of data - Hard to calculate

20 (Unavoidable Annual Real Losses, UARL) UARL= [18Lm + 0.8Nc + 25Lp]P (liter/day) Lm ค อ Distribution pipe length (km) Nc ค อ No of Connection (point) Lp ค อ Service pipe length (Km) P ค อ Pressure ( m) Standard operating Pressure = 50 m In each area that has different Component has unequal UARL 20

21 (ILI) CARL (Current annual real loss) UARL(Unavoidable Annual Real Losses) For example : CARL from WB table 1,000,000 Liters/day DMA has Pipe length = 30km, Service pipe = 3 km, 1500 concection, average P = 8 m UARL = (18x x x3)x8 = 14,520 Liter/sec ILI: /14520 = 68.9

22 Example (ILI) VS NRW NRW (%) CARL (Liters/Day) UARL (Liters/Day) ILI (times) Area A Area B Area C

23 ILI VS UFW in Branch office of MWA UFW ILI ILI %Loss

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25 System Input Volume High Pressure Optimize Pressure Poor Pressure 1)Pressure Management Revenue Water 2) Speed & Quality of Repairs Leakage management ELL UARL 3) ALC ALR - time % Non-Revenue Water CARL= 40% 4) Pipe Replacement 4 Element of Sustainable Leakage Control Strategy as Contineous Improvement Activities

26 Factor of loss volume No of Leak point -external force - Pipe Material Flow Rate - Pressure - Leak area Uncontroling - Metering Error - Illegal consumption -Pipe age - Soil settlement

27 ELL ELL Economic leakage level is the optimum Level of leakage at the lowest Total Cost Cost of water is vary direct to the amount of water Investment margin is vary indirect to %Reduce of NRW In term of exponentioal

28 Economic Level of Leakage (ELL) The Economic Balance Where the total cost is at a minimum Economic Leakage Level COST OF LEAKAGE CONTROL AND WATER LOSS Background Leakage and Reported Burst Cost of Leakage Control LOSSES (ML/D)

29 Leak Run Time Awareness Total volume loss= (A+L+R)time x Flow rate A L R Time Awareness Location Repair - Flow rate vary direct to Pressure - To reduce loss if can reduce ALR time

30 What is ALR time?

31 Pressure Management To control unnecessary flow rate To increase consumption flow rate To decrease error in meter recording For efficient in Water loss activities

32 Relation between Loss & Pressure FAVAD (Fixed and Variable Area Discharge) L = Cd x A x (2gP) 0.5 n1 (L/Lo) = (P/Po) N1 n1 Find from Pressure step test Generally =

33 Pressure Management concept

34 Pressure Management concept

35 Total Flow Flow independent to pressure (Consumption) Pressure Trend curve 25 Pressure (m) Flow dependent to pressure (Leak)

36 Pressure Management

37 Active leakage control?? Objective To Reduce Leak time A & L time Monitoring system Pin point Activities Loss & Ranking Warning & Aleart System

38 Pipe replacement concept - Limitation of Budget Objective To Reduce Repair time - Financial analysis in project Protect for reburst pipe - Evaluate & Priority of Pipe construction route Expand the life time of Pipe - Select the best of material & construction technique by economic value - Plan for new investment project

39 Q & A