Metal industry wastewaters

Effluent Standards for Metal Industry Wastewaters in Turkey... 

Weng CH, Huang CP (1994) Treatment of metal industrial wastewater by flyash and cement fixation. J Environ Eng 120 1470-1488... 

This preliminary study has shown that aminated ephedra waste biosorbent could be an interesting low-cost biosorbent for copper removal from aqueous solutions. The optimum absorption conditions of aminated ephedra waste pH is 4.7 contact time is 3 h Pseudo-second-order model is more applicable for the adsorption process. The biosorption of Cu + on aminated ephedra waste biosorbent obeys the Langmuir isotherm. According to the Langmuir equation, the maximum adsorption capacities of modified adsorbent for Cu + are 93.11 mg/g. The results obtained with aminated ephedra waste may be tested using metal-industry wastewater containing Cu +, since ephedra waste is an inexpensive source and therefore may have the advantage of economic viability. 

Industrial Wastewater Treatment. Industrial wastewaters require different treatments depending on their sources. Plating waste contains toxic metals that are precipitated and insolubiHzed with lime (see Electroplating). Iron and other heavy metals are also precipitated from waste-pidde Hquor, which requires acid neutralization. Akin to pickle Hquor is the concentrated sulfuric acid waste, high in iron, that accumulates in smokeless powder ordinance and chemical plants. Lime is also useful in clarifying wastes from textile dyeworks and paper pulp mills and a wide variety of other wastes. Effluents from active and abandoned coal mines also have a high sulfuric acid and iron oxide content because of the presence of pyrite in coal. 

Corrosion Resistance. Titanium is immune to corrosion in all naturally occurring environments. It does not corrode in air, even if polluted or moist with ocean spray. It does not corrode in soil and even the deep salt-mine-type environments where nuclear waste might be buried. It does not corrode in any naturally occurring water and most industrial wastewater streams. For these reasons, titanium has been termed the metal for the earth, and 20—30% of consumption is used in corrosion-resistance appHcations (see Corrosion and corrosion inhibitors). 

Wastewater Treatment and Metal Finishing Equipment. .. Your eomplete souree of new and reeonditioned industrial wastewater treatment, metal finishing, and biologieal treatment systems and equipment. URL http //wmi-inc.eom. 

Some very unique opportunities are also exclusively available to the primary metals industry. For example, the use of dry air control devices and dry cast quench operations have been adopted at some facilities to avoid the generation of contaminated wastewater. Additionally, many facilities are finding markets for byproducts (e.g., sulfides resulting from nonferrous smelting operations can be converted to sulfuric acid and subsequently sold) which avoids the need to discharge these contaminants.24 25... 

The nonferrous metals industry is divided into 61 subcategories by the type and source of the metal to be smelted and/or refined and by similar wastewater sources. Twenty-six of these subcategories... 

Johannes, R.D. et al., Electroplating/metal finishing wastewater treatment Practical design guidelines, Proc. 43rd Purdue Industrial Wastes Conference, West Lafayette, IN, 1988. 

FIGURE 9.8 Metal finishing wastewater treatment flow diagram. (Adapted from U.S. EPA, Treatability Manual, Volume II Industrial Descriptions, Report EPA-600/2-82-001b, U.S. Environmental Protection Agency, Washington, DC, September 1981.)... 

Metals have been shown to negatively affect nitrogen transformation and urea hydrolysis. For example, Antil et al.69 discovered that the microbial biomass in a soil receiving sewer water or industrial wastewater decreased with increasing concentrations of cadmium and nickel. The rate of urea hydrolysis was 1.6 times greater in an uncontaminated soil than in a soil containing 0.026 mg Ni g 1. Ammonium concentrations increased for up to 14 days in a soil containing over... 

Amuda, O.S., Amoo, I.A., Ipinmoroti, K.O., and Ajayi, O.O., Coaguation/flocculation process in the removal of trace metals present in industrial wastewater, Journal of Applied Sciences and Environmental Management, 10 (3), 159-162, 2006. 

Amuda, O.S., Giwa, A.A., and Bello, I.A., Removal of heavy metal from industrial wastewater using modified activated coconut shell carbon, Biochemical Engineering Journal, 36, 174-181, 2007. 

Metal industries use substantial quantities of water in processes such as metal finishing and galvanized pipe manufacturing in order to produce corrosion-resistant products. Effluent wastewaters... 

As was indicated in the previous section, the concentration of iron in the mixed wastewaters ranged from 5980 to 6100 mg/L its pH was 0.7 and zinc concentration was 15 pg/L. Since these wastewaters come only from acid baths and not from other processes of the plant, parameters such as cadmium and fluoride are not encountered. The discharge standards for the metal industry effluents set by the Turkish Water Pollution Control Regulation (Official Gazette, Table 15.7, September 4, 1988) are shown in Table 28.10.1... 

TETRA HDS [High density solids] A process for aiding the removal of heavy metals from wastewaters. It is a physical process which controls the characteristics of heavy metal hydroxide precipitates so that they settle quicker. The precipitates have a hydrophobic surface, so they are easy to de-water. Developed and licensed by Tetra Technologies, Houston, TX. Widely used by the iron and steel industry in the United States. Not to be confused with hydrodesulfurization, often abbreviated to HDS. 

Galiulin, R.F, Bashkin, V.N, Galiulina, R.R and Birch, P. (2001). A Critical Review Protection from Pollution by Heavy Metals — Phytoremediation of Industrial Wastewater. Land Contamination Reclamation, 9(4), 349-357... 

A lot of substances and components are present in wastewaters and can be measured, especially the emerging pollutants. However, in practice, the aggregate parameters (BOD, COD, TSS,...) and the physico-chemical ones (temperature, pH, dissolved oxygen, conductivity, turbidity,...) are more often monitored. The only specific compounds generally considered are the N and P forms, and in case of industrial wastewaters, some specific pollutants such as organics (phenolics, hydrocarbons,...) or metallic compounds. 

Biosorption or bioaccumulation, the process of passive cations binding by dead or living biomass, represents a potentially consecutive way of removing toxic metals from industrial wastewaters. Biosorption could be employed most effectively in a concentration range below 100 mg L 1, where other techniques are inactive or too expensive. 

Peters, R.W. Ku, Y. Bhattacharyya, D. Evaluation of recent treatment techniques for removal of heavy metals from industrial wastewaters. AIChE Symposium Series 1985, Si(243). 

HPT Research, Inc., has developed the ionic state modification (ISM) process for the treatment of acid mine drainage (AMD). ISM is an ex situ treatment technology that uses magnets, electricity, and proprietary chemical to precipitate heavy metals, remove sulfate ions, and neutralize acidity from AMD and industrial wastewaters. The end products of the process are a metal hydroxide sludge, a calcium sulfate sludge, and treated liquid effluent. The vendor claims that the metal hydroxide sludge may have some value as an ore, the calcium sulfate may be used as an agricultural additive to soils, and the liquid effluent is free of metal contamination and has low sulfate concentrations. 

Cutting oils and aqueous metal working fluids Industrial wastewater Agricultural waste and runoff Cyanide contamination Desulfurization of coal fines Chlorinated aliphatics Pesticides... 

This technology is currently commercially available. Polylonix Separation Technologies, Inc., offers polymer filtration for the treatment of metal-contaminated wastewaters from the electroplating and printed wire board industries. 

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