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Method and apparatus for manufacturing of static filtration media
ts+technologies Producing drinking water from sewage A panel of experts appointed by the Singaporean government has recommended that this small city state, which has one of the highest population densities in the world, should consider averting a future drinking water shortage by reclaiming its potable water from sewage. A two year study commissioned by Singapore’s Public Utilities board demonstrated that an advanced filtration process called NEWater would allow waste from homes and businesses to be rendered potable and mixed into exiting supplies. Two demonstration water treatment plants, each with a production capacity of 10 000 m”/day, have been built (one at Bedok and the other at Kranji). Both plants use microfiltration (UF) and reverse osmosis (RO) to remove particles and bacteria from sewage, followed by ultraviolet disinfection to ensure that the water is safe to drink. MF removes particles and bacteria larger than 0.2 microns in size, and protects the RO membrane against clogging. RO is much finer and filters out particles as small as 0.001 microns, which includes viruses, salts and dissolved organics. The plant at the Bedok Reclamation Works has successfully produced NEWater that exceeds the World Health Organization’s drinking water standards. Currently, Singapore buys more than half of its water from its neighbour Malaysia under treaties that are decades old, and more importantly begin to run out in 2011. Talks between the two countries were held this year, but ended without an agreement on future water prices.
Singapore has set targets to obtain 25% of its water supply from nontraditional sources, i.e. 15% from NEWater, 5% from sea water desalination and 5% from industrial water, by the year 2012.
recess treat
for difficult wastewater
rejected. The permeate is recycled back, and the concentrate is drained into a regional sewage system or disposed according to local regulations.
ure water generated without electricity
to
Because of the very nature of the raw chemicals the detergents industry uses, it produces large volumes of hard to treat wastewater, i.e. it is high in organics, suspended solids, dissolved solids, extreme pH, etc. Also the concentrations of the contaminants can very widely. Environmental regulations require that such wastewater is treated prior to disposal, but conventional treatments often result in high operational costs. Nirosoft Industries Ltd of Israel has developed a two stage membrane process that can treat this waste stream cost effectively The process allows the water to be recycled for washing, and therefore saves both water and waste disposal costs. The treatment is a basic physical separation process and is stable over varying feed conditions. The wastewater plant consistes of pretreatment, which is a combined phase separation and mechanical filtration. This is then followed by UF, which rejects the suspended solids and most of the colour, detergents and organics that cause COD (chemical oxygen demand). The permeate is then delivered to the second stage, while the concentrate is disposed. The second membrane stage uses RO, where dissolved solids and the remaining detergents, colour and organics are
A new compact membrane desalination device that is powered by water rather than electricity is being introduced by the Fraunhofer Patent Center for German Research, Germany Most modern desalination (deionization) systems work on the principle of RO. Salt water is fed under pressure into a module and flows over a synthetic membrane. The polymer material of the membrane allows water to pass through, but rejects the passage of salt ions. Desalinated or fully de-ionized water flows out the other side. However, this process is extermely energy intensive. The new system in contrast uses a water-jet pump to generate the pressure required to force the salt water through the membrane. The new devices, which is manufactured by UT&S GmbH, is already being successfully employed in electroplating plants. Here, the metallic salt baths must be cleaned at regular intervals, which requires de-ionized water because the introduction of foreign salts would adversely effect the properties of the metallic coatings. The use of such a device for the production of potable water remains some time in the future because the system can only operate if there is sufficient water with a minimum feed pressure. This is not always possible in areas with poorly developed infrastructures.
Patent Summaries Method and Apparatus for Separating Particles from Hot Gases, Foster Wheeler Energia Oy, Finland. WO 01/76722. Date of Publication: 18 October 2001.
Solids/Liquids Separator, Water Solutions (Aust] Pty Ltd, Australia. WO 01/88290. Date of Publication: 22 November
Monitoring of Volatile Organic Compounds in Groundwater with an In-situ Sampling Device, General Electric Co, USA. WO 01/77666. Date of Publication: 18 October 2001. Method and Apparatus for Manufacturing of Static Filtration Media, lnnova Pure Water Inc, USA. WO 01/80972. Date of Publication: 01 November 2001.
Filtratian+Separation
2001.
Filter Cloth and Method for Producing the Same, Sefar AG, WO 01/87454. Date of Publications: 22 November 2001. Systems and Methods for Processing Industrial Sludges, Continuum Environmental Inc, USA. wo 01/90005. Date of Publication: 29 November 2001,
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2002
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Singapore has set targets to obtain 25% of its water supply from nontraditional sources, i.e. 15% from NEWater, 5% from sea water desalination and 5% from industrial water, by the year 2012.
recess treat
for difficult wastewater
rejected. The permeate is recycled back, and the concentrate is drained into a regional sewage system or disposed according to local regulations.
ure water generated without electricity
to
Because of the very nature of the raw chemicals the detergents industry uses, it produces large volumes of hard to treat wastewater, i.e. it is high in organics, suspended solids, dissolved solids, extreme pH, etc. Also the concentrations of the contaminants can very widely. Environmental regulations require that such wastewater is treated prior to disposal, but conventional treatments often result in high operational costs. Nirosoft Industries Ltd of Israel has developed a two stage membrane process that can treat this waste stream cost effectively The process allows the water to be recycled for washing, and therefore saves both water and waste disposal costs. The treatment is a basic physical separation process and is stable over varying feed conditions. The wastewater plant consistes of pretreatment, which is a combined phase separation and mechanical filtration. This is then followed by UF, which rejects the suspended solids and most of the colour, detergents and organics that cause COD (chemical oxygen demand). The permeate is then delivered to the second stage, while the concentrate is disposed. The second membrane stage uses RO, where dissolved solids and the remaining detergents, colour and organics are
A new compact membrane desalination device that is powered by water rather than electricity is being introduced by the Fraunhofer Patent Center for German Research, Germany Most modern desalination (deionization) systems work on the principle of RO. Salt water is fed under pressure into a module and flows over a synthetic membrane. The polymer material of the membrane allows water to pass through, but rejects the passage of salt ions. Desalinated or fully de-ionized water flows out the other side. However, this process is extermely energy intensive. The new system in contrast uses a water-jet pump to generate the pressure required to force the salt water through the membrane. The new devices, which is manufactured by UT&S GmbH, is already being successfully employed in electroplating plants. Here, the metallic salt baths must be cleaned at regular intervals, which requires de-ionized water because the introduction of foreign salts would adversely effect the properties of the metallic coatings. The use of such a device for the production of potable water remains some time in the future because the system can only operate if there is sufficient water with a minimum feed pressure. This is not always possible in areas with poorly developed infrastructures.
Patent Summaries Method and Apparatus for Separating Particles from Hot Gases, Foster Wheeler Energia Oy, Finland. WO 01/76722. Date of Publication: 18 October 2001.
Solids/Liquids Separator, Water Solutions (Aust] Pty Ltd, Australia. WO 01/88290. Date of Publication: 22 November
Monitoring of Volatile Organic Compounds in Groundwater with an In-situ Sampling Device, General Electric Co, USA. WO 01/77666. Date of Publication: 18 October 2001. Method and Apparatus for Manufacturing of Static Filtration Media, lnnova Pure Water Inc, USA. WO 01/80972. Date of Publication: 01 November 2001.
Filtratian+Separation
2001.
Filter Cloth and Method for Producing the Same, Sefar AG, WO 01/87454. Date of Publications: 22 November 2001. Systems and Methods for Processing Industrial Sludges, Continuum Environmental Inc, USA. wo 01/90005. Date of Publication: 29 November 2001,
October
2002
17