7574-Wang-ch10_R2_030806 10 Treatment of Timber Industry Wastes Lawrence K. Wang Zorex Corporation, Newtonville, New York, U.S.A., and Lenox Institute of Water Technology, Lenox, Massachusetts, U.S.A. 10.1 INTRODUCTION The timber products processing industry encompasses manufacturers and processors who use forest materials to produce their goods and merchandise. Fifteen distinct subcategories of manufacturers and/or processors are engaged in the utilization of timber. This chapter addresses three major subsections of the entire industry: (a) wood preserving, both steaming and Boulton processes; (b) insulation board manufacturing; and (c) both wet–wet (S1S or smooth one side) and wet–dry (S2S or smooth two side) hardboard manufacturing. The number of dischargers in the timber products processing industry in the United States can be broken down as follows: (a) 19 direct dischargers; (b) 55 indirect dischargers; and (c) 172 zero dischargers. 10.1.1 Water Pollution The timber industry treats timber and wood products with chemical preservatives to protect the wood from degradation due to various organisms including fungi, and insects such as borers and termites. This treatment extends the range of applications and the service life of the wood. By design, the chemicals used to protect wood must be toxic to the target organisms, but they may also affect nontarget organisms and the environment [1]. The following groups of preservatives are commonly used for wood preservation: (a) copper chrome arsenate (CCA); (b) copper-based alternatives to CCA [ammoniacal copper quaternary (ACQ) and copper azole]; (c) boron; (d) creosote; and (e) pyrethroid- and metal- based light organic solvent preservatives (LOSPs). Section 10.2.1 presents a complete list of toxic chemicals used in wood preservation in the United States. Copper chrome arsenate (also known as CCA or chromated copper arsenate) consists of three metals: copper, chromium, and arsenic. All three metals pose a risk to the environment. Both hexavalent chromium and arsenic can cause cancer in humans. The CCA concentrate is diluted with water to create a working solution that is used in the pressure treatment of timber. CCA-treated timber is commonly a greenish color, but this is also often the case with the other copper-based preservatives. CCA-treated timber is registered for use by the industrial countries under their laws. The registered uses include internal building uses and external uses such as decks, walkways, fences, playground equipment and retaining walls, and some marine water applications such as wharfs and jetty piles. 409 © 2007 by Taylor & Francis Group, LLC 7574-Wang-ch10_R2_030806 10.1.2 Air Pollution and Health Hazards Published results of scientific studies indicate that copper, chromium, and arsenic slowly leach from CCA-treated timber products. All three metals pose a risk to human health and the environment, but also exist naturally in the environment in varying concentrations. Based on currently available evidence, CCA-treated wood does not pose any significant risk to the public. However, as arsenic is a known human carcinogen, it would be prudent to avoid unnecessary exposure to it. Some common sense tips to minimize unnecessary exposure to CCA-treated timber are: (a) treated wood should never be burned in open fires, stoves, fireplaces, or residential boilers; (b) hands should always be washed thoroughly after contact with any treated wood, especially before eating and drinking; (c) food should not come into direct contact with any treated wood; and (d) precautions should be taken to wear protective gear when working with CCA-treated wood. 10.1.3 Solid Wastes Disposal Small quantities of household CCA-treated timber waste (e.g., offcuts from a small job) could be placed in the owner’s rubbish bin, with the rest of owner’s household waste. CCA-treated timber waste from larger household building and demolition jobs is classified as inert waste, and can be disposed of to most suburban landfills. CCA-treated timber waste from industrial sources should only be disposed of to certain landfills. CCA-treated timber waste must not be burned or used as such. 10.1.4 Global Trends The timber industry is moving away from using pesticides such as CCA and creosote. The United States and Canada have moved to phase out the use of CCA to treat timbers intended for residential uses after December 2003 and Europe after June 2004. This trend appears to be driven by recent European risk assessments of arsenic, the application of the “precautionary principle,” and by perceived consumer demand shifts in North America [1]. The United States Environmental Protection Agency (USEPA) granted the cancellation of CCA registration for most residential uses of treated timber following an application to do so from the wood preservation industry. From January 1, 2004, the USEPA will not allow CCA products to be used to treat timber intended for most residential uses. The USEPA is continuing an assessment of the risks posed to children by arsenic leaching from CCA-treated timber. The European Commission has announced a partial prohibition on the use of CCA-treated timber, to take effect after June 2004. In addition to the residential uses being restricted in the United States and Canada, CCA preservatives will also not be used in the EU for timber destined for marine and most agricultural uses. The New Zealand Environmental Risk Management Authority (ERMANZ) has decided not to change the registration of CCA following a recent review of the potential public health risks arising from the continuing use of CCA-treated timber. ERMANZ found that the extent of any risk to public health arising from CCA remains unclear but is considering further investigation into the possible environmental and occupational health risks arising from CCA. The Ministry of Environment and the Ministry of Health of Manatu Hauora [2] announced their Guidelines for Selected Timber Treatment Chemicals in 1997. 410 Wang © 2007 by Taylor & Francis Group, LLC 7574-Wang-ch10_R2_030806 10.1.5 Cleaner Production and Economy Cleaner production aims at avoiding the generation of waste and emissions, by making more efficient use of materials and energy, through modifications in the production processes, input materials, operating practices, and/or products and services [3,4]. Van Berkel [4] illustrates how the timber industry and other industries were able to implement cleaner production practices and technologies. Aruna and Mercer [5] state the timber economy of the Mid-Atlantic Region in the United States. Specifically, the health and sustainability of ecosystems in an eight state region for the forest industries (including the timber industry) have been assessed. Wang and colleagues [6], meanwhile, present the costs of various wastewater treatment systems. 10.2 INDUSTRY SUBCATEGORY DESCRIPTION General descriptions and process descriptions for the major subcategories of the timber products processing point source category are introduced in this section. 10.2.1 Wood Preserving Creosote, pentachlorophenol (PCP), and formulations of water-soluble inorganic chemicals are the three most prevalent types of preservatives used in wood preserving. The most common of inorganic chemicals are the salts of copper, chromium, and arsenic. Fire retardants are formulations of salts, the principal ones being borates, phosphates, and ammonium compounds. Of plants in the United States, 80% use at least two of the three types of preservatives. Many plants treat with one or two preservatives plus a fire retardant. There are two basic steps in the wood preserving process: (a) preconditioning the wood to reduce its natural moisture content and to increase permeability; and (b) impregnating the wood with the desired preservatives. The preconditioning step may be performed by one of several methods including (a) seasoning or drying wood in large, open yards; (b) kiln drying; (c) steaming the wood at elevated pressure in a retort followed by application of a vacuum; (d) heating the stock in a preservative bath under reduced pressure in a retort (Boulton process); or (e) vapor drying, heating of the unseasoned wood in a solvent to prepare it for preservative treatment. All of these preconditioning methods have, as their objective, the reduction of the moisture content in the unseasoned stock to a point where the requisite amount of preservative can be retained in the wood. Conventional steam conditioning (open steaming) is a process in which unseasoned or partially seasoned stock is subjected to direct steam impingement at an elevated pressure in a retort. The maximum permissible temperature is set by industry standards at 1188C and the duration of the steaming cycle is limited by these standards to no more than 20 hours. Steam condensate formed in the retort exits through traps. The condensate is discharged to oil–water separators for removal of free oils. Removal of emulsified oils requires further treatment. In closed steaming, a widely used variation of conventional steam conditioning, the steam needed for conditioning is generated in situ by covering the coils in the retort with water from a reservoir and heating the water by passing process steam through the coils. The water is returned to the reservoir after oil separation and reused during the next steaming cycle. There is a slight increase in volume of water in the storage tank after each cycle due to water exuded from the Treatment of Timber Industry Wastes 411 © 2007 by Taylor & Francis Group, LLC 7574-Wang-ch10_R2_030806 wood. A small blowdown from the storage tank is necessary to remove this excess water and to control the level of wood sugars in the water. Modified closed steaming is a steam conditioning process variation in which steam condensate is allowed to accumulate in the retort during the steaming operation until it covers the heating coils. At that point, direct steaming is discontinued and the remaining steam required for the cycle is generated within the retort by utilizing the heating coils. Upon completion of the steaming cycle, and after recovery of oils, the water in the cylinder is discarded. Preconditioning is accomplished in the Boulton process by heating the stock in a preservative bath under reduced pressure in the retort. The preservative serves as a heat transfer medium. After the cylinder temperature has been raised to operating temperature, a vacuum is drawn, and water, which is removed in vapor form from the wood, passes through a condenser to an oil–water separator. At this point low-boiling fractions of the preservative are removed. The Boulton cycle may have a duration of 48 hours or longer for large poles and piling. This fact accounts for the lower production per retort day as compared to plants that steam condition. The vapor-drying process consists of exposing wood in a closed vessel to vapors from any one of the many organic chemicals that are immiscible with water and have a narrow boiling range. The following is a summary of toxic pollutants found in significant quantities in the wood preserving category [7,8]: . Pentachlorophenol . Phenol . 2,4-Dimethylphenol . 2,4-Dichlorophenol . Copper . Chromium . 3,4-Benzofluoranthene . Benzo(k)fluoranthene . Pyrene . Benzo(a)pyrene . Indeno (1,2,3-cd)pyrene . Benzo(ghi)perylene . Arsenic . Nickel . Zinc . Fluorene . Phenol . Fluoranthene . Chrysene . Bis(2-ethylhexyl)phthalate . Naphthalene . Acenaphthylene 10.2.2 Insulation Board Manufacturing Insulation board is a form of fiberboard, which in turn is a broad generic term applied to sheet materials constructed from ligno-cellulosic fibers. Insulation board is a “noncompressed” fiberboard, which is differentiated from “compressed” fiberboards, such as hardboard, on the basis of density. Densities of insulation board range from about 0.15 to 0.50 g/cm 3 (9.5–31 lb/ft 3 ). 412 Wang © 2007 by Taylor & Francis Group, LLC 7574-Wang-ch10_R2_030806 There are more than 16 insulation board plants in the United States with a combined annual production capacity of over 330 million square meters (3600 million square feet) on a 13 mm (0.5 in.) basis. Sixteen of the plants use wood as a raw material for some or all of their production. One plant uses bagasse exclusively, and one plant uses waste paper exclusively for raw material. Four plants use mineral wood, a nonwood-based product, as a raw material for part of their insulation board production. Five plants produce hardboard products as well as insulation board at the same facility. Insulation board can be formed from a variety of raw materials including wood from softwood and hardwood species, mineral fiber, waste paper, bagasse, and other fibrous materials. In this section, only those processes employing wood as raw materials are considered. Plants utilizing wood may receive it as roundwood, fractionated wood, and/or whole tree chips. Fractionated wood can be in the form of chips, sawdust, or planer shavings. The toxic pollutants found in significant quantities in insulation board manufacturing wastewater are: . Copper . Nickel . Zinc . Phenol . Benzene . Toluene 10.2.3 Hardboard Manufacturing Hardboard is a form of fiberboard, which is a broad generic term applied to sheet materials constructed from ligno-cellulosic fibers. Hardboard is a “compressed” fiberboard, with a density greater than 0.50 g/cm 3 (31 lb/ft 3 ). The thickness of hardboard products ranges between 2 and 13 mm (nominal 1/12 to 7/16 in.). Production of hardboard by the wet process method is usually accomplished by thermomechanical fiberization of the wood furnish. One plant produces wet–dry hardboard using primarily mechanical refining. Dilution of the wood fiber with fresh or process water then allows the formation of a wet mat of a desired thickness on a forming machine. This wet mat is then pressed either wet or after drying. Chemical additives help the overall strength and uniformity of the product. The uses of manufactured products are many and varied, requiring different processes and control measures. The quality and type of board are important in the end use of the product. Hardboard that is pressed wet immediately following forming of the wet-lap is called wet–wet or smooth-one-side (S1S) hardboard; that which is pressed after the wet-lap has been dried is called wet–dry or smooth-two-side (S2S) hardboard. There are about 16 wet process hardboard plants in the United States, representing an annual production in excess of 1.5 million metric tons per year. Seven of the plants produce only S1S hardboard. Nine plants produce S2S hardboard. Of these nine, five plants also produce insulation board, while three plants also produce S1S hardboard. The toxic pollutants found in significant quantities in the hardboard manufacturing wastewater are [8]: . Copper . Phenol . Chromium . Benzene Treatment of Timber Industry Wastes 413 © 2007 by Taylor & Francis Group, LLC 7574-Wang-ch10_R2_030806 . Nickel . Toluene . Zinc 10.3 WASTEWATER STREAMS The timber products processing industry was analysed in a screening program for the 129 USEPA priority pollutants. Those pollutants detected in screening were further analyzed in a verification sampling analysis. The minimum detection limit for toxic organics is 10 mg/L and for toxic metals, 2 mg/L. Any concentration below its detection limit is presented in the following tables as BDL, below detection limit. 10.3.1 Wood Preserving Wastewater The quantity of wastewater generated by a wood preserving plant is a function of the method of conditioning used, the moisture content of the wood being treated, and the amount of rainwater draining toward the treating cylinder. Most wood preserving plants treat stock having a wide range of moisture contents. Although most plants use predominantly one of the major conditioning methods, many plants use a combination of several conditioning methods, and the actual quantity of wastewater generated by a specific plant may vary considerably. The average wastewater volume from 14 Boulton plants is reported to be 21,200 L/day (5600 gal/day) or 139 L/m 3 (1.03 gal/ft 3 ) of production. The average wastewater volume for eight closed loop steaming plants is 5200 L/day (1370 gal/day) or 60 L/m 3 (0.45 gal/ft 3 ). The average wastewater volume for 10 plants that treat significant amounts of dry stock is 13,300 L/day (3510 gal/day) or 121 L/m 3 (0.91 gal/ft 3 ). Additionally the average wastewater volume for 14 open steaming plants is 32,300 L/day (9250 gal/day) or 236 L/m 3 (1.87 gal/ft 3 ). Tables 1A and B present the concentrations of toxic pollutants found in streaming subcategory raw wastewater and in Boulton subcategory raw wastewater, respectively. Table 1C presents the concentrations of toxic pollutants found in both streaming and Boulton subcategory treated effluent (Source: USEPA). 10.3.2 Insulation Board Manufacturing Wastewater Insulation board plants responding to the data collection portfolio reported fresh water usage rates ranging from 95,000 to 5,700,000 L/day for process water (0.025–1.5 MGD). One insulation board plant that also produces hardboard in approximately equal amounts, uses over 15 million L/day (4 MGD) of fresh water for process water. Water becomes contaminated during the production of insulation board primarily through contact with the wood during fiber preparation and forming operations. The vast majority of pollutants are fine wood fibers and soluble wood sugars and extractives. More specifically, potential sources of wastewater in an insulation board plant include: (a) chip washwater; (b) process whitewater generated during fiber preparation (refining and washing); (c) process whitewater generated during forming; and (d) wastewater generated during miscellaneous operations (dryer washing, finishing, housekeeping, etc.) The average unit flow for an insulation board mechanical refining plant is 8.3 L/kg (2000 gal/ton), assuming the plant produces a full line of insulation board products and practises internal recycling to the extent practicable. Table 2 presents concentrations of toxic pollutants found in insulation board manufacturing raw wastewater [8]. 414 Wang © 2007 by Taylor & Francis Group, LLC 7574-Wang-ch10_R2_030806 Table 1A Concentrations of Toxic Pollutants Found in Streaming Subcategory Raw Wastewater Toxic pollutant (mg/L) Range Median Metals and inorganics Antimony BDL–47 BDL Arsenic 3–14,000 33 Beryllium BDL–19 BDL Cadmium BDL–10 BDL Chromium 1–98 23 Copper 8–850 120 Lead BDL–91 14 Mercury BDL–BDL BDL Nickel 3–150 28 Selenium BDL–7 BDL Silver BDL–6 BDL Thallium BDL–10 BDL Zinc 120–820 310 Phthalates Bis(2-ethylhexyl)phthalate BDL–440 BDL Phenols 2-Chlorophenol BDL–42 BDL 2,4-Dimethylphenol BDL–6,600 130 Pentachlorophenol 1,200–160,000 16,000 Phenol 1,400–87,000 16,000 2,4,6-Trichlorophenol BDL–530 BDL Monocyclic aromatics Benzene BDL–2,800 1,000 Ethylbenzene 37–2,100 380 Toluene 27–3,200 500 Polycyclic aromatic hydrocarbons Acenaphthene 1,100–55,000 1,500 Acenaphthylene BDL–1,200 720 Anthracene/phenanthrene 2,000–39,000 6,500 Benzo(a)anthracene BDL–7,700 160 Benzo(a)pyrene BDL–2,700 BDL Benzo(b)fluoranthene BDL–1,700 BDL Benzo(ghi)perylene BDL–320 BDL Benzo(k)fluoranthene BDL–3,900 BDL Chrysene BDL–4,700 73 Dibenzo(ah)anthracene BDL–430 BDL Fluoranthene 630–35,000 1,600 Fluorene 820– 48,000 1,500 Indeno(1,2,3-cd)pyrene BDL–5,500 BDL Naphthalene 380–45,000 2,200 Pyrene 360–22,000 810 Halogenated aliphatics Methyl chloride BDL–700 77 Chloroform BDL–20 BDL BDL, below detection limit. Source: USEPA. Treatment of Timber Industry Wastes 415 © 2007 by Taylor & Francis Group, LLC 7574-Wang-ch10_R2_030806 Table 1B Concentrations of Toxic Pollutants Found in Boulton Subcategory Raw Wastewater Toxic pollutant (mg/L) Range Median Metals and inorganics Antimony BDL–13 3 Arsenic 3–14 7 Beryllium BDL–2 BDL Cadmium BDL–5 BDL Chromium 4–3,900 9 Copper 80–1,600 110 Lead BDL–14 5 Mercury BDL–3.7 BDL Nickel 20–210 94 Selenium 2–53 3 Silver BDL–2 BDL Thallium BDL–2 BDL Zinc 320–26,000 840 Phthalates Bis(2-ethylhexyl)phthalate BDL–1,500 430 Phenols 2-Chlorophenol BDL 2,4-Dimethylphenol BDL Pentachlorophenol 27,000 Phenol 71 2,4,6-Trichlorophenol BDL Monocyclic aromatics Benzene BDL Ethylbenzene BDL Toluene BDL Polycyclic aromatic hydrocarbons Acenaphthene BDL–2,800 BDL Acenaphthylene BDL–2,100 BDL Anthracene/phenanthrene BDL–1,500 920 Benzo(a)anthracene BDL–34 BDL Benzo(a)pyrene BDL Benzo(b)fluoranthene BDL Benzo(ghi)perylene BDL Benzo(k)fluoranthene BDL Chrysene BDL–18 BDL Dibenzo(ah)anthracene BDL Fluoranthene BDL–280 BDL Fluorene BDL–820 BDL Indeno(1,2,3-cd)pyrene BDL Naphthalene BDL–3,100 BDL Pyrene BDL Halogenated aliphatics Methyl chloride 2,600 Chloroform BDL BDL, below detection limit. Source: USEPA. 416 Wang © 2007 by Taylor & Francis Group, LLC 7574-Wang-ch10_R2_030806 Table 1C Concentrations of Toxic Pollutants Found in Both Streaming and Boulton Subcategory Treated Effluent Toxic pollutant (mg/L) Range Median Metals and inorganics Antimony BDL –14 BDL Arsenic 2–7,000 35 Beryllium BDL –13 BDL Cadmium BDL–7 BDL Chromium BDL–4,000 8 Copper 18–270 57 Lead BDL–37 4 Mercury BDL–2 BDL Nickel 2– 150 18 Selenium BDL– 39 2 Silver BDL–4 BDL Thallium BDL–7 BDL Zinc 47 –41,000 200 Phthalates Bis(2-ethylhexyl)phthalate BDL–300 BDL Phenols 2-Chlorophenol BDL 2,4-Dimethylphenol BDL–140 BDL Pentachlorophenol 32–8,300 2,700 Phenol BDL–16,000 15 2,4,6-Trichlorophenol BDL Monocyclic aromatics Benzene BDL –33 10 Ethylbenzene BDL–20 BDL Toluene BDL –140 23 Polycyclic aromatic hydrocarbons Acenaphthene BDL–18,000 90 Acenaphthylene BDL–190 BDL Anthracene/phenanthrene BDL–37,000 59 Benzo(a)anthracene BDL– 3,400 BDL Benzo(a)pyrene BDL–290 BDL Benzo(b)fluoranthene BDL–2,500 BDL Benzo(ghi)perylene BDL –63 BDL Benzo(k)fluoranthene BDL–210 BDL Chrysene BDL–19,000 BDL Dibenzo(ah)anthracene BDL Fluoranthene BDL–17,000 110 Fluorene BDL –16,000 36 Indeno(1,2,3-cd)pyrene BDL–110 BDL Naphthalene BDL–36,000 33 Pyrene BDL–9,400 77 Halogenated aliphatics Methyl chloride 13–1,900 140 Chloroform BDL–23 BDL BDL, below detection limit. Source: USEPA. Treatment of Timber Industry Wastes 417 © 2007 by Taylor & Francis Group, LLC 7574-Wang-ch10_R2_030806 10.3.3 Hardboard Manufacturing Wastewater Significant amounts of water are required for production of hardboard by wet process. Plants responding to the data collection portfolio reported fresh water usage rates for process water ranging from approximately 190,000 to 19 million L/day (0.05–5 MGD). One plant produces both hardboard and insulation board in approximately equal amounts, and reported fresh water use of over 15 million L/day (4 MGD). Process water becomes contaminated during the production of hardboard primarily through contact with the wood raw material during the fiber preparation, forming, and, in the case of S1S hardboard, pressing operations. The vast majority of pollutants in the wastewater consist of fine wood fibers, soluble wood sugars, and extractives. Additives not retained in the board also add to the pollutant load. Process whitewater is the water used to process and transport the wood from the fiber preparation stage through mat formation. Process whitewater produced by the dewatering of stock at any stage of the process is usually recycled to be used as stock dilution water. However, in order to avoid undesirable effects in the board when elevated concentrations of suspended solids and dissolved organic materials occur, excess process whitewater is discarded. Potential wastewater sources in the production of wet process hardboard include: (a) chip washwater; (b) process whitewater generated during fiber preparation (refining and washing); (c) process whitewater generated during forming; (d) hot press squeezeout water; and (e) wastewater generated during miscellaneous operations (dryer washing, finishing, housekeeping, etc.). A unit flow of 12 L/kg (2800 gal/ton) is considered to be representative of an S1S hardboard plant that produces a full line of hardboard products and that practises internal Table 2 Concentrations of Toxic Pollutants Found in Insulation Board Subcategory Raw Wastewater, USEPA Verification Data Toxic pollutant (mg/L) Number of Samples Range Median Metals and inorganics Antimony 4 0.67–3 1.5 Arsenic 4 1.6–3.3 2.5 Beryllium 4 0.5– 0.83 0.5 Cadmium 4 0.5– 1.0 0.66 Chromium 4 1.3– 11 4.9 Copper 4 200–450 310 Lead 4 1.3–21 3.3 Mercury 4 1–7.5 5.8 Nickel 4 8.8– 240 58 Selenium 4 3.3–5.0 4.5 Silver 4 0.5– 0.6 0.5 Thallium 4 0.5– 0.83 0.7 Zinc 4 250 –720 530 Toxic organics Chloroform 3 BDL–20 BDL Phenol 3 BDL–40 BDL Benzene 3 BDL–70 50 Toluene 3 BDL–60 40 BDL, below detection limits. Source: USEPA. 418 Wang © 2007 by Taylor & Francis Group, LLC [...]... , 210 ,8 3,000 700 78 540 ,180 ,3.2 140 ,22 ,24 51 ,29 ,16 ,6.4 , 110 ,38 ,1.6 ,6.4 35 ,3.2 ,24 ,24 ,1.6 83 NM 88 92 NM NM NM 94 NM NM 99 95 96 96 NM NM 7574-Wang-ch10_R2_030806 Treatment of Timber Industry Wastes 423 Table 7 Wood Preserving Phenols Analysis Data Averages for Plants with Current BPT in Place Waste load (kg /100 0 cu.m) Number of plants Phenols 2-Chlorophenol 2,4-Dimethyl phenol 2,4,6-Trichlorophenol... wastewater 10. 4 WASTEWATER TREATMENT The following sections address the current level of in-place treatment technology and the raw and treated effluent loads and percent reduction for several pollutants and several plants Information is organized with respect to the aforementioned subcategories 10. 4.1 Wood Preserving Wastewater Treatment The following sections present the current level of in-place treatment. .. Chemicals; Manatu Hauora, June 1997; pp 37, http://www.mfe.govt.nz/publications/ hazardous/ timber-guide-jun97 /chapter- 1-jun97.pdf Wang, L.K.; Krouzek, J.V.; Kounitson, U Case Studies of Cleaner Production and Site Remediation; United Nations Industrial Development Organization (UNIDO): Vienna, Austria, 1995; Training Manual No DTT- 5-4 -9 5, 136 Van Berkel, C.W.M Cleaner production: a profitable road for sustainable... Taylor & Francis Group, LLC 9 – 100 12 – 26 5 – 13 7 – 60 17 – 5,500 440 – 14,000 20 – 800 1.2 – 310 60 – 2,400 18 – 60 5 – 180 5 – 13 3,000 – 24,00 340 1.9 –120 0.003 – 0.04 37 0.009 7574-Wang-ch10_R2_030806 Treatment of Timber Industry Wastes 421 Spray-assisted solar evaporation: 26% of all plants; Effluent recycle to boiler or condenser: 17% of all plants Current level of in-place technology, steaming,... follows: Primary gravity oil– water separation: 100 % of all plants; Chemical flocculation and/or oil absorptive media: 100 % of all plants; Aerated lagoon: 100 % of all plants; Holding basin: 100 % of all plants; Spray-assisted solar evaporation: 100 % of all plants; Effluent recycle to boiler or condenser: 100 % of all plants Current level of in-place technology, steaming, with indirect dischargers... Raw Wastewater and Treated Effluent Characteristics, Annual Average BOD (kg/Mg) TSS (kg/Mg) Plant number Raw waste Treated effluent Percent reduction Raw waste Treated effluent Percent reduction 360 36 889 4.6 21 1.3 1.0 0.28 0.07 76 99 95 0.88 31 0.46 1.2 1.5 0.16 NM 95 65 NM, not meaningful Source: USEPA © 2007 by Taylor & Francis Group, LLC 7574-Wang-ch10_R2_030806 Treatment of Timber Industry Wastes... for wastewater treatment at a hardboard manufacturing plant producing S2S hardboards Use of a settling pond and aerated lagoon system for wastewater treatment at a hardboard manufacturing plant producing S1S hardboards Use of a nonspecified system for wastewater treatment at a hardboard manufacturing plant producing S2S hardboards Use of a settling ponds and aerated lagoon system for wastewater treatment. .. aerated lagoon system for wastewater treatment at a structure/ decorative insulation board plant using thermomechanical process Use of oxygen-activated sludge system and clarifier for wastewater treatment at an insulation board/hardboard plant using thermomechanical process Use of an aerated lagoon, evaporation pond, and self-contained discharger (irrigation) system for wastewater treatment at an insulation... activated sludge system for wastewater treatment at a structure/ decorative insulation board plant using mechanical process Use of a floc-clarifier, aerated lagoon, and discharge to POTW system for wastewater treatment at a structure/decorative insulation board plant using mechanical process Use of a settling pond, aerated lagoon, and oxidation pond system for wastewater treatment at an insulation board... phenols for plants with current pretreatment technology in place and current BPT in place [8] In addition, Tables 8 and 9 present data for average raw and treated waste loads and percent removals of metals for plants with current BPT in place [8] 10. 4.2 Insulation Board Manufacturing Wastewater Treatment The following is a summary of the current level of in-place treatment technology for six plants: . detection limit. Source: USEPA. Treatment of Timber Industry Wastes 417 © 2007 by Taylor & Francis Group, LLC 7574-Wang-ch10_R2_030806 10. 3.3 Hardboard Manufacturing Wastewater Significant amounts. Guidelines for Selected Timber Treatment Chemicals; Manatu Hauora, June 1997; pp. 37, http://www.mfe.govt.nz/publications/ hazardous/ timber-guide-jun97 /chapter- 1-jun97.pdf. 3. Wang, L.K.; Krouzek,. announced their Guidelines for Selected Timber Treatment Chemicals in 1997. 410 Wang © 2007 by Taylor & Francis Group, LLC 7574-Wang-ch10_R2_030806 10. 1.5 Cleaner Production and Economy Cleaner