Wastewater discharge

The surviving U.S. plants have embraced all types of waste treatment processes (see Wastes treatment, hazardous waste Wastes, industrial). The most desired poUution prevention processes are those which reduce the total amount of waste discharged. Treatment and disposal are less strongly emphasized options. Zero wastewater discharge faciHties and water recycling processes are becoming more common (55,56). 

Neutralization. Wastewater discharge usually requires a pH between 6 and 9. Exceptions are a biological process in which microbial respiration degrades acidity (acetic acid is oxidized to CO2 and H2O), or one in which the CO2 generated by microbial respiration neutralizes caustic alkalinity (OH ) to bicarbonate HCO. ... 

In 1972 the U.S. Legislature passed PubUc Law 92-500, which requires certain levels of treatment for industrial wastewater discharges. Effluent guideline criteria (expressed as kilograms poUutant per unit of production) have been developed for each industrial category to be met by specified time periods. 

Other problems that can be associated with the high dust plant can include alkaH deterioration from sodium or potassium in the stack gas deposition on the bed, calcium deposition, when calcium in the flue gas reacts with sulfur trioxide, or formation and deposition of ammonium bisulfate. In addition, plugging of the air preheater as weU as contamination of flyash and EGD wastewater discharges by ammonia are avoided if the SCR system is located after the FGD (23). 

Are wastewaters discharged to a municipal sewage treatment system Discharge in compliance with the treatment system s permit ... 

Using mass-integration strategies of segregation, recycle, interception and sink/ source manipulation, fresh-water usage can in principle be completely eliminated. Hence, for the same reaction conditions and water losses, tl target for wastewater discharge can be calculated from the overall water balance as follows (Fig. 4.4) ... 

The objective of this problem is to employ mass integration techniques to reduce wastewater discharge while alleviating any buildup of ionic species. In this problem, we focus our attention on chlorine ions as the key species. 

The higher the quality of the surface waters providing the supply, the more stringent will be the treated wastewater discharge consent standards imposed by the NRA on effluents returned to the surface waters. 

Wesolowski EA (1999) Simulation of effects of wastewater discharges on Sand Creek and lower Caddo Creek near Ardmore, Oklahoma. Investigations Report 99-4022. US Geological Survey, Denver, Colorado... 

There are an estimated 800 plants in the U.S. involved in the primary or secondary recovery of nonferrous metals. These plants represent 61 subcategories. However, many of these subcategories are small, represented by only one or two plants, or do not discharge any wastewater. This chapter focuses on 296 facilities that produce the major nonferrous metals [aluminum, columbium (niobium), tantalum, copper, lead, silver, tungsten, and zinc]. The volume of wastewater discharged in this industry varies from 0 to 540 m3/T (0 to 160,000 gal/t) of metal produced.13 The global size of the industry is reflected in Table 3.1 (reported in 1000 USD) for the top 20 export countries for nonferrous base metal waste and scrap.4 Here T = metric ton = 1000 kg = 2204.6 lb, t = 2000 lb. 

Wastewater discharge, known as liquid pollution in a facility, makes up a small portion of the total wastestream from foundries.2 Wastewater mainly comes from the noncontact cooling water used to... 

This subcategory is applicable to all wastewater discharges resulting from or associated with forging of aluminum or aluminum alloy products. The forging subcategory consists of approximately 15 plants, 12 of which use only this process. Thus, only 20% of the plants have operations that overlap with one or more other subcategories. 

Thirty plants in the aluminum forming industry use etch or cleaning lines. Rinsing is usually required following successive chemical treatments within these etch or cleaning lines. Wastewater discharge values tend to increase as the number of rinses increase. Table 5.11 summarizes the classical and toxic pollutant data for etch line rinses. 

All four wastewater treatment systems introduced in this chapter are technically feasible for treating nickel-chromium plating wastewater in order to meet the maximum permissible concentrations shown in Table 6.1 for industrial wastewater discharge into a municipal sewerage system15 or Table 6.2 for discharge to surface waters.21... 

Maximum Permissible Concentrations of Industrial Wastewater Discharge into Municipal Systems... 

Maximum Permissible Concentrations of Electroplating Wastewater Discharge to Surface Waters... 

Characteristics of Typical Wastewater Discharge of Conventional Reduction-Precipitation System3... 

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