Pulp and paper industry wastewater

Vieira M, Tavares CR, Bergamasco R, and Petrus JCC. Application of ultrafiltration-complexation process for metal removal from pulp and paper industry wastewater. J. Membr. Sci. 2001 194 273-276. 

EPA 821/R-93-017, Analytical Methods for the Determination of Pollutants in Pulp and Paper Industry Wastewater. October 1993. National Technical Information Service, Springfield, VA. 

Oxygen is used to treat municipal wastewater and wastewater from the pulp and paper industry (see Aeration, water treatment Wastes, industrial Water). Many of these water appHcations can use VSA-produced oxygen (advantage /). Demonstration and development programs are in place that use oxygen to oxidize sludge from municipal waste and bum hazardous wastes and used tires (advantages 1—4). 

The pulp and paper industry and potable and wastewater treatment industry are the principal markets for aluminum sulfate. Over half of the U.S. aluminum sulfate produced is employed by the pulp and paper industry. About 37% is used to precipitate and fix rosin size on paper fibers, set dyes, and control slurry pH. Another 16% is utilized to clarify process waters. The alum sold for these purposes is usually Hquid alum. It is frequendy acidic as a result of a slight excess of H2SO4. Aluminum sulfate consumption by the pulp and paper industry is projected to remain constant or decline slightly in the near term because of more efficient use of the alum and an increased use of alkaline sizing processes (13). 

The pulp and paper industry is the largest industrial process water user in the U.S.5 In 2000, a typical pulp and paper mill used between 15,140 and 45,420 L (4000 to 12,000 gal) of water per ton of pulp produced. 1 2 3 4 General water pollution concerns for pulp and paper mills are effluent solids, biochemical oxygen demand (BOD), and color. Toxicity concerns historically occurred from the potential presence of chlorinated organic compounds such as dioxins, furans, and others (collectively referred to as adsorbable organic halides, or AOX) in wastewaters after the chlorination/ extraction sequence. With the substitution of chlorine dioxide for chlorine, discharges of the chlorinated compounds have decreased dramatically. 

The pulp and paper industry generates hazardous wastes, but most are associated with wastewater, which is rendered nonhazardous in wastewater treatment or neutralization units within the manufacturing facilities and therefore is not subject to RCRA requirements. Also, black liquor is exempt as a solid waste if it is reclaimed in a recovery furnace and reused in the pulping process. 

The organic chemical industry, the food processing industry, the pulp and paper industry, the textile industry, and the petroleum industry are important industries that produce organic process wastes. Unlike inorganic process wastes, they contain dissolved and insoluble matter in the main wastewater stream thus, they are more difficult to handle for disposal. They have its characteristic biological problems and spontaneous interaction with the surrounding environment, particularly, under high solar radiation. 

Specific effluents have also been subjected to WRF-mediated remediation studies. Decolourization, dechlorination and detoxification of highly toxic bleach plant effluents derived from the pulp and paper industry have been reported [26-28], while degradation and decolourization of synthetic dyes due to the non-specificity of the LMEs have been widely documented [29, 30], Likewise, treatment of the acidic, phenolic-rich olive oil mill wastewater has shown COD reduction, decolourization and dephenolization [31-34],... 

Wastewater-derived alkylphenolic compounds have been studied extensively. The concentrations of nonylphenol ethoxylates (NPEOs), as the strongly prevalent sub-group of APEOs, determined in the influents of WWTPs (Table 6.1.4), varied widely among various WWTPs from <30 to 1035 pg L 1. However, values can go up to 22 500 pg L-1 in industrial wastewaters (especially from tannery, textile, pulp and paper industry). Levels of octylphenol ethoxylates (OPEOs) are significantly lower, comprising approximately 5-15% of total APEOs in WWTP influents, which is congruent with their lower commercial use. 

Thermophilic Anaerobic Reactor Applications. Pulp and paper industries typically discharge warm (50°C) effluents, and conventional reactors operating under mesophilic conditions require cooling of such wastewaters. Attempts have been made periodically by various groups to investigate the possibility of applying thermophilic anaerobic processes to pulp and paper discharges, but to date there is no conclusive evidence to prove the superior performances of thermophilic reactors as compared to their mesophilic counterparts. 

Over the last decade, much interest has been generated in monitoring environmental problems and associated risks of wastes, in particular, wastewaters generated by the pulp and paper industries. A major goal is to reassess the target pollutant levels and consider the use of risk-based discharge permit values rather than the absolute endpoint values. This risk-based approach requires analytical tools that can quantify the ecotoxic characteristics of discharges rather than the absolute concentration of specihc pollutants or the values of lumped pollution parameters such as BOD, COD, and so on. 

Anaerobic-aerobic processes have a high potential for the treatment of pulp mill wastewater containing xenobiotic compounds. The pulp and paper industry is under great pressure to remove chlorophenols, chlorinated aliphatic hydrocarbons, and chlorinated dioxins and furans from wastewater. The Canadian government requires that pulp mill effluent contain no measurable level of dioxins or furans (Murray Richardson, 1993)- Such regulations require novel wastewater treatment technologies for the complete removal of target compounds. 

Zhang, Q.H., Xu, Y., Wu, W.Z., Xiao, R.M., Feng, L., Schramm, K.W., Kettrup, A., 2000b. PCDDs and PCDFs in the wastewater from Chinese pulp and paper industry. Bull. Environ. Contamin. Toxicol. 64, 368-371. 

NCASI. 1993. Summary of data reflective of pulp and paper industry progress in reducing the TCDD/TCDF content of effluents, pulps and wastewater treatment sludges. National Council of the Paper Industry for Air and Stream Improvement, Inc. Special report no. 93-08. 

Because of the large volume of wastewater generated in hydraulic debarking and the problems associated with recycling it, waste treatment and disposal techniques used by the pulp and paper industry are applicable. This involves the employment of heavy-duty clarifiers to remove suspended solids, followed by biological treatment to remove oxygen-demanding substances. 

In addition to in situ soil applications, Fenton reagent has also been studied for treatment of industrial waste streams. For example, the treatment of residual Kraft black liquor from the pulp-and-paper industry has been shown to be effective [42]. Near-complete degradation of lignin (95-100%) and decolorization were achieved under optimized conditions. Basic oxygen furnace slag was evaluated as a source of iron for degradation of 2-chloro-phenol in industrial wastewater [43], and favorable results were achieved. 

Hakulinen R. The use of enzymes for wastewater treatment in the pulp and paper industry—a new possibility. Water Sci Technol 1988 20(1) 251-262. 

The principal use for sodium sulfide in the United States is for dehairing leather before tanning, in Western Europe for leather tanning, and in Japan for production of chemicals and dyes. The major use for NaHS in the United States is the pulp and paper industry, followed by metals and minerals. In Japan, sodium hydrosulfide is mainly used in the production of chemicals and dyes, in wastewater treatment, and in leather tanning.11... 

To reduce production of chlorinated organics during bleaching, the pulp and paper industry has replaced chlorine with chlorine dioxide. Chlorine dioxide or its primary precursor, sodium chlorate, can be produced by the low-tonnage chlorine industry with the same hardware that is used for synthesis of chlorine and hypochlorite. This simple transition from chlorine to chlorine dioxide synthesis may be the reason for the less-than-anticipated usage of hydrogen peroxide in the pulp and paper industry. Increasing use of chlorine dioxide could also lead to its applications in other effluent treatment areas such as industrial wastewater remediation. 

The treatment and safe disposal of waste is equally important whether it be waste generated by the pulp and paper industry, by the leather industry or gaseous waste. Recently, in addition to other membrane-based processes, demand has grown in the wastewater treatment industry for a process that uses both a biological stage and a membrane module, known as the membrane bioreactor (MBR) process. The bioreactor and membrane module each have a specific function (1) the biological degradation... 

Membrane technology may become essential if zero-discharge mills become a requirement or legislation on water use becomes very restrictive. The type of membrane fractionation required varies according to the use that is to be made of the treated water. This issue is addressed in Chapter 35, which describes the apphcation of membrane processes in the pulp and paper industry for treatment of the effluent generated. Chapter 36 focuses on the apphcation of membrane bioreactors in wastewater treatment. Chapter 37 describes the apphcations of hollow fiber contactors in membrane-assisted solvent extraction for the recovery of metallic pollutants. The apphcations of membrane contactors in the treatment of gaseous waste streams are presented in Chapter 38. Chapter 39 deals with an important development in the strip dispersion technique for actinide recovery/metal separation. Chapter 40 focuses on electrically enhanced membrane separation and catalysis. Chapter 41 contains important case studies on the treatment of effluent in the leather industry. The case studies cover the work carried out at pilot plant level with membrane bioreactors and reverse osmosis. Development in nanofiltration and a case study on the recovery of impurity-free sodium thiocyanate in the acrylic industry are described in Chapter 42. 

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