Pressure management for Large

Transcription

1 Pressure management for Large diameter pipe systems Case Study Scottish Water Muirhouse PRV David Humphrey

2 Water treatment works Control in Water networks Booster pumps Reservoirs Pump Fed Gravity Fed Level Control Pressure sustaining Trunk Main Network Domestic Demand Single Feed DMA Pressure Managed Area Multi Feed DMA Flow management valve Industrial Demand Borehole pump Booster pumps with Variable speed drives Remotely controlled Pressure management valve

3 City of Edinburgh Pressure management Zone Population: 500,000 rising to 1,200,000 During summer festival season 18 trunk main PRV sites. Combination of multiple feed and single feed zones. PRVs range in Sizes from: 300mm - 600mm 6 Service reservoirs with flow control

4 Muirhouse PRV Zone Supplies 6 x District Metered Areas (DMAs) PRV is located in a 300mm Trunk Main PRV serving over 15,000 Properties Muirhouse PRV Demand profile: Primarily residential Connected to Tourist attractions including the Royal Yacht Britannia DMA s are pressure managed and optimised Considered to have low levels of leakage

5 Benefits of Pressure management Reduce Leakage by lowering Average zone night pressure (AZNP) Extend pipeline service life Reduce pressure surge Reduce frequency of asset failure Improve customer service less disruption Demand management Effect of Pressure related consumption Result: Calm Network!

6 Limitations of hydraulic control Manual set-point adjustment requires site visits which mean: Health and Safety considerations often challenging site locations Traffic management measures Labour intensive Lacks flexibility to response pro-actively to extreme events (e.g fire demands, seasonal demand) Lacks ability to optimise networks pressure during lower demand period to achieve additional leakage savings

7 Challenges of installing electroinc interfaces No mains power supply available to majority of PRV chambers - Cost prohibitive and long delays for installation. No fixed-line telephone lines - Reliant on Mobile phone Networks Battery life impaired by high power consumption needed for GPRS communication in poor reception areas.

8 Valve Requirements Remote Pressure Set-Point Control For pressure optimisation SCADA Connectivity with Local manual control for near real time incidence response Data Acquisition of key inputs including pressure, flow, battery levels Security Default to fixed pressure mode in the event of power/comms failure Self-powered- Autonomous Robust Withstand high levels of humidity within the chamber

9 Autonomous Power Valve Controller 24V DC Inlet pressure transducer 8 bar Actuator 4 bar Extra capacity to measure: Flow Temperatue turbidity Valve Stem position Outlet pressure transducer 12 Volt battery and Power management system 200V AC e-power IP Turbine OUTPUT: 16 Watts Pressure Reducing Valve Valve controller 3.0 Watts Pressure transmitters: 0.5 Watts Actuator (max) 6.0 Watts TOTAL ENERGY CONSUMPTON: 9.5 Watts

10 Valve Installation Valve Controller Valve size: 300mm 2 x 7Ah Batteries Inlet pressure : 8 bar Outlet pressure: 4 bar Estimated flow: 170 l/s Turbine OPERTING MODES: Auto: Time v Pressure Auto: Flow v Pressure Remote: Manual pressure setpoint Local Manual Pressure setpoint Motorised PRV Pilot

11 Pressure management for Large diameter pipe systems Motorised pilot Manual pilot Flowmeter

12 Control system features 2-Way communication Data Acquisition and Command outputs 15 minute data transmission of all inputs uploaded to Cla-Val Link2Valve web platform Local Control /programming (by hand directly on the valve controller) Remote Control via Link2Valve web platform

13 Results savings achieved 6.2 L/sec = 0.54 ML/d

14 Conclusion Small reductions in pressure across a large number of connections can offer significant reductions in leakage. Self powered intelligent Valve interfaces provide a cost effective and robust solution for the active monitoring and optimisation of water networks in near real-time allowing them to respond to planned and unplanned operational conditions.