Reclaim water

Low viscosity urethane polymers have been prepared from castor od and polymeric isocyanates (82). These low mix viscosity systems are extremely usehd for potting electrical components where fast penetration without air voids, and fast dispensing cycles are desirable. Very low viscosity urethane systems containing castor polyols have been prepared for use in reclaiming water-logged buried telephone cable and for encapsulating telephone cable sphces (83—86). 

Water Requirement The water requirement per spiral can range from 1.0 to 2.5 L/s (15 to 40 gal/min) this includes 0.2 to 0.6 L/s (3 to 10 gal/min) of water used in the wash-water channel. An attractive feature of the spiral is that reclaimed water can generally be used in all except the veiy final upgrading step. 

National Research Council. Use of Reclaimed Water and Sludge in Food Crop Production, National Academy of Press, Washington, D.C., 1996. 

Membrane processes, such as hyperfiltration, can also reduce the health risks caused by the presence of pollutants such as pesticides, heavy metals, endocrine disrupters, pathogens and viruses. This is especially important in case where human beings can get in contact with reclaimed water. 

De Peyster A, Donohoe R, Slymen DJ. 1993. Aquatic biomonitoring of reclaimed water for potable use The San Diego health effects study. Journal of Toxicology and Environment Health 39 121-142. 

Barker-Reid F, Fox EM, Faggian R (2010) Occurrence of antibiotic resistance genes in reclaimed water and river water in the Werribee Basin, Australia. J Water Health... 

The El Segundo, CA, Chevron refinery takes a further step in water reuse [76]. It receives 16,300 m /day of reclaimed water to feed its boilers. Microfiltration (ME) and RO are used to treat secondary effluent from the Hyperion Wastewater Treatment Plant to provide low-pressure boiler feedwater while a second pass RO is used to produce high-pressure boiler feedwater. 

Nickel Sulfamate. Vltramon, a Thomas and Betts subsidiary, installed a 1 gpm ARO system to recover rinses and recycle nickel bath used to plate electronic capacitors. Previously, Vitramon had used an ion exchange system to remove the nickel. Ion exchange regenerant was shipped to a reclaimer. Water was reused. Ion exchange cost of operation was 4,000 per month. The ARO system maintains the rinse at less than 40 ppm nickel. Savings from nickel recovery and avoided treatment cost will provide a payback of approximately 10 months. 

Johnson, W.T., Phelps, R.W. and Beatson, P.J. (Oct. 1997) Wastewater reuse using membranes. IDA World Congress on Desalination and Water Science, Madrid. Adham, S., Kumar, M. and Pearce, W.H. (2004) Development of a model for brackish and reclaimed water membrane desalination costs. Proceedings of the International Conference on Desalination Costing, Limassol, Cyprus. 

Some of the largest plants for seawater desalination, wastewater treatment and gas separation are already based on membrane engineering. For example, the Ashkelon Desalination Plant for seawater reverse osmosis (SWRO), in Israel, has been fully operational since December 2005 and produces more than 100 million m3 of desalinated water per year. One of the largest submerged membrane bioreactor unit in the world was recently built in Porto Marghera (Italy) to treat tertiary water. The growth in membrane installations for water treatment in the past decade has resulted in a decreased cost of desalination facilities, with the consequence that the cost of the reclaimed water for membrane plants has also been reduced. 

Reserve pit water A drilling operation should consider reclaiming water from the reserve pit using a dewatering technique. The reclaimed water can then be used as rig-wash water, makeup water for the drilling fluid system, and other rig water usage. Additionally, collected stormwater runoff may be suitable for use. 

Reclaimed water with the chemical characteristics given in the table is being considered for use as makeup water for a cooling tower. Calculate the composition of the blowdown flow if five cycles of concentration are to be used. Assume that the temperature of the hot water entering the cooling tower is 50°C (120°F) and the solubility of CaSCTt is about 2200 mg/L as CaCC>3 at this temperature. 

Bahri, A. (1998). Fertilizing value and polluting load of reclaimed water in Tunisia. Water Res. 32, 11, 3484-3489. 

Contactors are also used in polishing loop for final degassing and to treat recycled or reclaimed water (Figure 2.6). The exact UPW process configuration depends on the specific needs in the plant and on quality of water supply to the plant. But no... 

Combining flocculation and coagulation in a pretreatment process has also been smdied. In a key paper by Lopez-Ramirez et al. [64], the secondary effluent from an activated sludge unit was pretreated, before RO, with three levels intense (coagulation-flocculation with ferric chloride and polyelectrolite and high pH sedimentation), moderate (coagulation-flocculation with ferric chloride and polyelectrohte and sedimentation), and minimum (only sedimentation). The optimum for membrane protection, in terms of calcium, conductivity, and bicarbonates reduction, was the intense treatment. Membrane performance varied with pretreatment but not reclaimed water quahty. The study recommended intense pretreatment to protect the membrane. 

In recent years, efforts have been undertaken to conserve water due to the growing demand for a limited resource. As a result, water reuse is being employed, especially in the Western United States. Water reuse is when wastewater generated from a community is reclaimed for a beneficial use such as irrigation for ornamental or agricultural crops, decorative water features, industrial application and with advanced treatment potable water. The use of reclaimed water may expose the public to chemical and microbial contamination from the wastewater stream. Therefore, for each type of beneficial reuse, treatment standards are being established to protect public health. 

The cleared ICB effluent is approximately 98 wt percent water, 0.8 wt percent sodium sulfate, 0.7 wt percent sodium chloride, and traces of agent impurities and degradation products (PMACWA, 2006). The WRS and the brine reduction system (BRS) reclaim water from the biotreatment system effluent and the blowdown from both the cooling tower and the steam boiler. In addition, some process water passes through an RO system to feed the steam boilers and munitions washout system the retentate is fed to the WRS. 

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