Wastewater discharges treatment

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). 

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. 

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

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... 

This treatment process involves the use of chemical compounds to initiate a chemical reaction in the wastewater stream, which ends up neutralizing negatively charged colloids and thus, causing changes that would alter the nature of the wastewater, particularly to conform to the standard of wastewater discharge.4 The treatment process possesses an inherent disadvantage, especially net increase in the dissolved constituents of the wastewater, which can hinder reuse of the wastewater.2 Common chemical treatment processes are discussed below. 

As one of the top water consumers, the food industry is estimated to account for about 9% of water and wastewater treatment market sales. The wastewater discharged from food manufacturing facilities has become a major concern. In this chapter, we will be discussing a series of physical,... 

Treatment of dye-contaminated wastewater discharged from the textile and other dye-stuff industries is necessary to prevent contamination of soil and surface and ground water. Currently, there are several physicochemical and biological methods... 

One of the most observed degradation pathways of non-ionic surfactants of ethoxylate type in the biochemical wastewater treatment process is the bond scission between the lipophilic alkyl chain and the hydrophilic ethoxylate moieties. The resulting ethoxylate compounds, PEG or PPG, are highly polar and are not quite easy to degrade, therefore often they can be observed in wastewater discharges. So, APCI— FIA-MS(+) product ion spectra of selected [M + NH4]+ ions, which were under suspicion as PEG (general formula HO—(CH2—CH2—0) H)... 

These types of surfactants have the largest share of world-wide total production [14] and the highest application rates in household, trade and industrial processes. As these compounds were handled mainly in aqueous systems, they were consequently discharged with the waste-water. After a more or less efficient wastewater treatment (WWT) process, which results in an elimination, i.e. degradation by wastewater biocoenosis and/or adsorption of the surfactants to the sludge, these polar compounds and their metabolites either reach the environment by wastewater discharges or are adsorbed to wastewater sludge,... 

Nonylphenol ethoxylates (NPEOs) are extensively used as surfactants in industrial products (see Chap. 1). NPEOs are a mixture of polyethoxylated mono-alkylphenols, predominantly para-substituted, and are used in the manufacturing of paints, detergents, inks, and pesticides [435, 446]. Surfactants are common water pollutants because of their use in aqueous solutions, which are discharged into the environment in the form of wastewater from treatment plants or sludge stored in landfills. Degradation products of alkylphenol polyethoxylates, i. e., nonylphenol (NP), have the potential to be bioaccumulated, thereby becoming toxic to aquatic [447] and soil microorganisms [435,448]. 

The volume of wastewater produced from a potable water treatment plant (either a conventional sedimentation filtration plant or an innovative flotation filtration plant) amounts to about 15% of a plant s total flow. Total wastewater recycle for production of potable water may save water and cost, and solve wastewater discharge problems [15,35-38]. 

Three categories of regulatory limitations apply to wastewater discharge from industrial facilities such as oilfields and petroleum refineries [20]. The first category includes effluent limitations, which are designed to control those industry-specific wastewater constituents deemed significant from the standpoints of water quality impact and treatability in conventional treatment systems. In the United States, these limitations are the EPA Effluent Guidelines, issued under Public Law 92-500. 

Many refineries in the United States are being required to control whole-effluent toxicity as well as specific toxic constituents to meet new wastewater discharge limits. There can be a variety of toxic constituents that may need to be controlled, depending on waste characteristics and local water quality objectives. The more common constituents in refinery wastewater include cyanide and heavy metals. The treatment processes for control of whole-effluent toxicity, cyanide, and heavy metals are discussed below. 

Inhibition values measured at 11 different time periods in an effluent from a biological wastewater treatment plant with the luminescent bacteria test are shown in Figure 1. The pT-values of this industrial wastewater discharged into the Rhine River ranged between 4 and 12 (Tab. 3). It should be noted, however, that high values were measured prior to an internal processing change in the plant and that low values were obtained after the adjustment. 

Sources of contaminated water in the manufacture of products for which no wastewater discharge is allowed include wet-type debarking operations, steam or hot-water conditioning of logs, veneer drier washwater, glue equipment washwater, and certain types of preservative treatments. Only limited data are available on the quantity and characteristics of these effluents (Table III). Each source of wastewater is discussed below in terms of the problem that it presents and the technology that is available to deal with it. 

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