Use of highly polished reclaimed water as a means to supplement water resources in the Maltese Islands. Dr.Ing.Paul Micallef

Transcription

1 Use of highly polished reclaimed water as a means to supplement water resources in the Maltese Islands. Dr.Ing.Paul Micallef 1

2 BACKGROUND inh/km Malta Netherlands Belgium United Kingdom Germany Italy Luxembourg Czech Republic Denmark Poland Portugal Slovakia France Slovenia Austria Spain Greece Lithuania Estonia Sweden Finland Demographic Characteristics highest population density; AND Climatic Characteristics semi-arid climate

3 BACKGROUND Malta Cyprus Denmark Poland Belgium Germany United Kingdom Spain Italy France Netherlands Lithuania Portugal Luxembourg Estonia Slovakia Austria Hungary Ireland Latvia Slovenia Sw eden Finland Water Availability (m3/cap/year) Lowest Water Availability per Capita in the EU

4 BACKGROUND Water availability has always been a limiting factor for the country s development. Demand management (utilisation of drip irrigation, flow restrainers) Supply augmentation (at domestic level, using cisterns to catch rain falling on roof tops and at regional level, the building of water catchment reservoirs, dams in valleys) Dr.Ing.Paul Micallef 4

5 BACKGROUND Water Conservation Introduction of RO Introduction of Multi-flash distillers

6 DEMAND AND SUPPLY OTHERS,6,265 INDUSTRY,5,967 OVER ABSTRACTION GROUNDWATER, 17, m AGRICULTURE, 29,272 DESALINATION, 17, DOMESTIC, 22,955 SUSTAINABLE GROUNDWATER ABSTRACTION, 25,000 0 RAINWATER HARVESTING, DEMAND DEMAND AND SUPPLY SUPPLY Dr.Ing.Paul Micallef 6

7 POLICY APPROACH Increase efficient use (various tools used); Introduction of new sources of water to be used in lieu of groundwater (reducing overabstraction to sustainable levels) HOWEVER If demand not controlled, it will keep increasing with supply Dr.Ing.Paul Micallef 7

8 DEMAND AND SUPPLY OTHERS,6,265 INDUSTRY, 5,967 POTENTIAL POLISHED RECLAIMED WATER, 12, HPRW Project, 7, m AGRICULTURE, 29,272 DESALINATION,17, DOMESTIC,22,955 SUSTAINABLE GROUNDWATER ABSTRACTION,25,000 0 RAINWATER HARVESTING,4,000 DEMAND SUPPLY Dr.Ing.Paul Micallef 8

9 Controlling Demand HPRW, 24, m Others, 6,265 Industry, 5,967 Desalination,17, Agriculture, 20, Sustainable groundwater, 25, Domestic, 16,705 0 Rainwater Harvesting, 4,000 DEMAND SUPPLY Dr.Ing.Paul Micallef 9

10 Treated Sewage Effluent and main problems related to its use especially in agriculture Malta case GOZO Ras il-hobz 4,000 m 3 /day, 2008 Ic-Cumnija 8,000 m 3 /day, 2009 Ta Barkat 55,000 m 3 /day 2011 MALTA St.Antnin 12,000 m 3 /day, 1980 Dr.Ing.Paul Micallef 10

11 Salinity issues Network Infrastructural shortcomings Brine discharges into the network Dr.Ing.Paul Micallef 11

12 Infrastructural deficiencies POTABLE SUPPLY MONITORING SITE SEWAGE MONITORING SITE CHLORIDE CONTENT 200<>400mg/l 400<>600mg/l 600<>800mg/l 800<>2,000mg/l >2,000mg/l The Sewerage Master Plan (COWI, 1992) refers to various instances where infiltrations of sea water into the sewers were identified in particular in those areas where the sewers are Built-up Area Industrial Zones Hotels Main Sewer Lines situated below sea-level. One of the areas identified was the Sliema-Gzira area. In fact, conductivities in the sewers are of around an order of magnitude higher than that of the potable water supply in the area.

13 Sea-Water Intrusion Reduction

14 Sea-water infiltration increases: Transfer pumping costs Salinity of wastewater entering STPs thereby increasing re-use process costs

15 Rehabilitation works using trenchless in-situ repairs comprising localised sewer patching, polyurethane resin injection in manhole walls and sewer lining (CIPP)

16 Possible solutions to use available treated sewage effluent Further polishing to ensure quality standards required for reuse; Solve salinity issues at source; Dr.Ing.Paul Micallef 16

17 The main objective of the proposed project is to provide alternative water resources to replace part of the abstraction of groundwater in Malta thus protecting and preserving the Environment. In particular, the intention is to produce seven million cubic metres of water per annum to replace groundwater abstraction, thereby reducing the pressure on the water table to an environmentally sustainable groundwater abstraction level of around 25 million cubic metres per annum. 17

18 Conceptual Approach WSC OPERATIONS Metering & Billing CONSUMER (Potable Water) Metering & Billing CONSUMER (Second Class Water) RO PLANT PSs BHs WATER RECLAMATION PLANT UF/RO SEWAGE TREATMENT PLANT SEA GROUNDWATER SEA 2 nd CLASS + INDIRECT POTABLE (RECHARGE) UF and RO polished treated wasetwater for both second class purpose and also indirect potable use via artificial recharge 18

19 Management of the water cycle in Malta From source, collection, purification and supply of drinking water, to treatment of used water and turning it into Highly Polished Reclaimed water, drainage of storm water Rain Sea Dr.Ing.Paul Micallef 19 Direct use of surface water for non-potable Use

20 Planned and potential treatment volume Modular approach = flexibility to respond to efficiency measures Distribution EU funds used (ERDF, EARDF) Dr.Ing.Paul Micallef 20

21 Polishing and blending set-up Dr.Ing.Paul Micallef 21

22 Economic quality level of supply : On site increase in quality when required (MORISO) Solar-Powered Mobile Polishing Plant for high-end agriculture Designed and engineered in-house by WSC Engineers

23 Client can choose different water-quality according to crop requirements down to 400µS; Fully-autonomous, solar-powered operation and complete mobility; User-friendly.

24 Plans Reduction in level of treatment (discharge control) Tackling emerging pollutants (although no heavy industry in Malta) - Lower Production Costs - Dr.Ing.Paul Micallef 24

25 Results from Mediwat The polished treated effluent produced by this pilot plant was periodically analysed for a number of indicators of organic pollutants which could potentially be present in domestic sewage. These indicators are Pharmaceuticals Carbamezepine, Acetominophen, Diazemam, Diclofenac, Dilantin, Fluoxetine, Gemfibrozil, Hydrocodone, Ibuprofen, Iopromide, Meprobamate, Naproxen, Pentoxifylene, Mefanamic Acid Solvents/Plasticizers/Surfactants Dibutylphtalate, Glycol Ether, Alkyl Benzene, Dibromochloromethane, Perfluorooctanic Acid, Perfluorooctanesulfonic Acid, BisphenolA Personal Care Products Caffeine, Galoxolide, Oxybenzone, TCEP and DEET Steroids Androstenedione, Estradiol, Estriol, Estrone, Ethinylestradiol, Progesterone, Testosterone AntiMicrobial Agents Trimethoprim, Triclosan, Sulfamedthoxazole, Erythromycin. Analysis for all these indicator parameters with the exception of Dibromochloromethane yielded a negative result (<0.01ug/l). The above list of parameters was based on literature survey. Further tests are in the pipeline. Dr.Ing.Paul Micallef 25

26 Driving Factors Further reduce the present demand levels; Maximize the use of non-potable water sources, with particular reference to treated sewage effluent; Provide water to customer in a rational and sustainable way Provide the lowest cost of water service to all users Public input shows support of non-potable development Dr.Ing.Paul Micallef 26

27 Demand sources The main sources of Demand for the Treated Sewage Effluent (TSE) have been identified namely: The domestic sector; Those who undertake an economic activity such as, tourism, farms, agriculture, industry, commercial, government and others; Those who produce an environmental or public goods aspect such as landscaping, recreational (watering of public parks as well as irrigation of sports facilities such as football and golf turfs); aquifer recharge. Dr.Ing.Paul Micallef 27

28 BENEFITS OF HIGHLY POLISHED RECLAIMED WATER USE the enhancement of the water balance by creating additional water resources the protection and preservation of the environment. Dr.Ing.Paul Micallef 28

29 Feed (Gozo) Product (Gozo) Parameters High Low High Low Conductivity ms/cm Chlorides mg/l Nitrates mg/l NO Ammonia mg/l N Negligible Total Suspended Solids mg/l COD mg/l Results obtained from the Ultra Filtration and Reverse Osmosis Pilot Plant experiment in Gozo Dr.Ing.Paul Micallef 29

30 Feed (Bulebel) Product (Bulebel) Parameters High Low High Low Conductivity ms/cm Chlorides mg/l Nitrates mg/l NO 3 - Ammonia mg/l N Total Suspended Solids mg/l COD mg/l Results obtained from the Ultra Filtration and Reverse Osmosis Pilot Plant experiment in Malta Dr.Ing.Paul Micallef 30

31 Product Quality ECond (us/cm) Feed UF Product RO Product Product Quality 250 Nitrate (mg/l) Feed UF Product RO Product 0 Dr.Ing.Paul Micallef 31

32 Product Quality COD (mg/l) Feed UF Product RO Product Product Quality Total Bacterial cfu/ml Feed UF Product RO Product Dr.Ing.Paul Micallef 32

33 The Water Reclamation Project is divided into three distinct subprojects. These three sub-projects have been identified according to their geographic location (namely Gozo, Malta North and Malta South) as follows: Equipment (Ultra-filtration followed by reverse osmosis and by advanced oxidation stages); Civil Works (intended to house the equipment above); Infrastructure (intended to transport final product to end use point). Dr.Ing.Paul Micallef 33

34 Beyond the proposed project, other actions and issues to address.. Public Perception; Costs (lowering treatment needs by upstream solutions. Thus, monitoring of disposal of sewage in the network with testing of sewage chemical quality need to be stepped up to reduce salinities and therefore need for eventual further treatment); Demand management; The whole proposed set up invariably will require a very strict monitoring programme both at source (STP) and most importantly after the polishing stage; Water Safety Plan Well-equipped Laboratory Stability to ensure private investment Other solutions to address the water demand/supply gap include Rainwater harvesting Artificial recharge AN INTEGRATED APPROACH IS IMPORTANT AND THIS CAN ONLY BE ACHIEVED THROUGH A NATIONAL WATER PLAN Dr.Ing.Paul Micallef 34

35 THANK YOU Web Site: Dr.Ing.Paul Micallef 35