Filtration system treatment

Indian Ion Exchange and Chemical Industries - Produces reverse osmosis and demineralization systems, base exchange softeners, clarifiers and filters, degassers and de-aerators, filtration and micro filtration systems, effluent treatment plant...http //www.indianionexchange.com. ... 

Innovative Flotation-Filtration Wastewater Treatment Systems. 249... 

FIGURE 6.1 Relationship between H2S03 and HS03 at various pH values. (Taken from Krofta, M. and Wang, L.K., Design of Innovative Flotation-Filtration Wastewater Treatment Systems for a Nickel-Chromium Plating Plant, U.S. Department of Commerce, National Technical Information Service, Springfield, VA, Technical Report PB-88-200522/AS, January 1984.)... 

Alternatively, hexavalent chromium can be reduced, precipitated, and floated by ferrous sulfide. By applying ferrous sulfide as a flotation aid to a plating waste with an initial hexavalent chromium concentration of 130 mg/L and total chromium concentration of 155 mg/L, an effluent quality of less than 0.05 mg/L of either chromium species can be achieved if a flotation-filtration wastewater treatment system is used.15... 

INNOVATIVE FLOTATION-FILTRATION WASTEWATER TREATMENT SYSTEMS... 

There are two innovative flotation-filtration wastewater treatment systems that are technically feasible for the treatment of the nickel-chromium plating wastewater. 

Another innovative flotation-filtration wastewater treatment system adopts the innovative use of the chemical ferrous sulfide (FeS), which reduces the hexavalent chromium and allows separation of chromium hydroxide, nickel hydroxide, and ferric hydroxide in one single step at pH 8.5. Figure 6.7 illustrates the entire system. Again, a DAF-filtration clarifier plays the most important role in this wastewater treatment system. 

It is seen from Figure 6.7 that this system is much simpler, more cost-effective, and easier to operate in comparison with all other process systems discussed earlier. The treatment efficiency of the new flotation-filtration system is expected to be higher than that of the conventional reduction-precipitation system. The new flotation-filtration system also requires much less land space.15... 

FIGURE 6.6 Innovative flotation-filtration wastewater treatment system using conventional chemicals. 

The treatment efficiencies of the two innovative flotation-filtration wastewater treatment systems (Figures 6.6 and 6.7) are expected to be higher than those of the conventional reduction-precipitation system. 

The innovative flotation-filtration wastewater treatment system (Figure 6.6) using conventional chemicals has the highest flexibility and best performance. When desirable, the innovative chemical FeS or equivalent can also be used. 

Another innovative flotation-filtration wastewater treatment system using FeS (Figures 6.7 and 6.8) is highly recommended if a totally new system is to be designed and installed for treatment of nickel-chromium plating wastewater. This system is extremely compact, easy to operate, and cost-effective. Treatment efficiency is also excellent. 

Granular bed filters are used in ten coil coating plants to remove residual solids from the clarifier effluent, and are considered to be tertiary or advanced wastewater treatment. Chemicals may be added upstream to enhance the solids removal. Pressure filtration is also used in this industry to reduce the solids concentration in clarifier effluent and to remove excess water from the clarifier sludge. Figure 7.4 shows a granular bed filter and Table 7.13 presents the heavy metal removal data of a lime clarification and filtration system. 

Wang, L.K., Design and specification of Pittsfield Water Treatment System consisting of air flotation and sand filtration, Water Treatment, 6, 127-146, 1991. 

Krofta, M. and Wang, L.K., Development of innovative flotation-filtration systems for water treatment, part A first full-scale Sandfloat Plant in U.S., Proc. American Water Works Association Water Reuse Symposium III, San Diego, CA, 3, 1226-1237,1984. 

An inexpensive commercial carbon filtration system (Car-bolator) was found to have considerable potential in solving the waste treatment problem at pest control facilities. The Carbolator operates by the recirculation of wastewater through a bed of activated carbon. 

The use of filtration to polish biological treatment system effluent has become more popular in recent years because of more stringent discharge requirements. The 1977 EPA survey of petroleum refineries indicated that 27 of 259 plants used filtration as part of the existing treatment scheme and 16 others planned to install filtration systems in the near future [5]. Filtration can improve effluent quality by removing oil, suspended solids, and associated BOD and COD, and carryover metals that have already been precipitated and flocculated. Improved effluent filtration in one recent instance helped a Colorado refinery to meet the newly adopted discharge toxicity requirements [49]. 

Some fixed filtration systems are relatively inexpensive. For example, constructed wetlands and sand filters are generally the most successful methods of polishing the treated wastewater effluent from lagoons. These systems have also been used with more traditional, engineered primary treatment technologies such as septic tanks and primary clarifiers. In such constructed wetlands, the system utilizes the roots of plants to provide substrate for the growth of attached bacteria, which utilize the nutrients present in the effluents and for the transfer of oxygen. 

Advanced treatment plants employ either granular filters or membrane filters. The former is exemplified by activated carbon, whereas membrane filtration has been developed only in recent memory. Besides the general principle of excluding contaminants based on size, these advanced filtration systems also have a charge that enables them to exclude particles, with the removal of anionic compounds being higher than that of nonionic ones. Both systems come at a premium. 

For an ABG system to treat 15 gal of pesticide wastes per day, the capital cost is 14,950 and the average treatment cost is 1.15/gal. The ABG system coupled with a pigment filtration system for treating ink wastes costs 1.98/gal, assuming capital cost is averaged over 5 years (D13970S). 

The Biocube aerobic biofilter is an ex situ off-gas filtration system that is commercially available. The technology utilizes microbes to biologically oxidize volatile organic compounds (VOCs) and complex odors. It can be used in conjunction with vapor-vacuum-extraction (VVE), a process that draws gases from subsurface soil. These gases often require further treatment before being released into the atmosphere. Biocube has been field tested and has been implemented at over 100 sites for the treatment of hydrocarbon vapors. The technology has also been successfully used for odor control at a variety of sites. In addition, the Biocube system can treat odor and VOC emissions simultaneously. The units are modular, so additional stacks can be added as needed for increased flow and/or removal rates. 

The SBP membrane filtration system concentrates contaminants and reduces the volume of contaminated groundwater, surface water, storm water, landfill leachates, and industrial process water. This hyperfiltration system consists of stainless steel tubes coated with a multilayered membrane, which is formed in-place using proprietary chemicals. The membrane filtration system can be used with an SBP bioremediation system or another technology as part of a treatment train. 

Mechanical forces can disturb the elaborate structure of the enzyme molecules to such a degree that de-activation can occur. The forces associated with flowing fluids, liquid films and interfaces can all cause de-activation. The rate of denaturation is a function both of intensity and of exposure time to the flow regime. Some enzymes show an ability to recover from such treatment. It should be noted that other enzymes are sensitive to shear stress and not to shear rate. This characteristic mechanical fragility of enzymes may impose limits on the fluid forces which can be tolerated in enzyme reactors. This applies when stirring is used to increase mass transfer rates of substrate, or in membrane filtration systems where increasing flux through a membrane can be accompanied by increased fluid shear at the surface of the membrane and within membrane pores. Another mechanical force, surface... 

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