Considering that wastes are resources to be recovered is the key for the success of an IE project using a cleaner production technology. Several successful IE case histories are presented here to demonstrate the advantages of cleaner production for hazardous wastes management [40].
Galvanizing is an antirust treatment for steel. The old process involved large quantities of expensive materials, and highly polluting hazardous wastes.
The cleaner production technologies include: a induction heating to melt the zinc, b electromagnetic field to control the molten zinc distribution, and c modern computer control of the process. The advantages include total suppression of conventional plating waste, smaller inventory of zinc, better process control of the quality and thickness of the zinc coating, reduced labor requirements, reduced maintenance, and safer working conditions.
With the cleaner production technologies in place, capital cost is reduced by two-thirds compared to the traditional dip-coating process. The payback period was three years when replacing existing plant facilities. Sulfur dyes are important dyes yielding a range of deep colors, but they cause a serious pollution problem due to the traditional reducing agent used with them. The old dyeing process involved four steps: a a water soluble dye was dissolved in an alkaline solution of caustic soda or sodium carbonate; b the dye was then reduced to the affinity form; c the fabric was dyed; and d the dye was converted back into the insoluble form by an oxidation process, thus preventing washing out of the dye from the fabric.
The advantages include: reduction of sulfide in the effluent, improved settling characteristics in the secondary settling tank of the activated sludge plant , less corrosion in the treatment plant, and elimination of the foul smell of sulfide in the work place. When solvent-based adhesives were used at Blueminster, UK, the components of the adhesive, normally a polymer and a resin capable of becoming tacky were dissolved in a suitable organic solvent.
The adhesive film was obtained by laying down the solution and then removing the solvent by evaporation. In many adhesives, the solvent was a volatile organic compound VOC that evaporated to the atmosphere, thus contributing to atmospheric pollution. The cleaner production process here involves the use of water-based adhesives to replace the solvent-based adhesives. The economic benefits are derived mainly from the lack of use of solvents and can amount to significant cost savings on equipment, raw materials, safety precautions, and overheads.
Tanning is a chemical process that converts hides and skins into a stable material. Tanning agents are used to produce leather of different qualities and properties. Trivalent chromium is the major tanning agent, because it produces modern, thin, light leather suitable for shoe uppers, clothing, and upholstery.
A cleaner production technology has been developed to recover and reuse the trivalent chromium from the spent tannery liquors for both cost saving and pollution control. Tanning of hides is carried out with chromium sulfate at pH 3.
After tanning, the solution is discharged by gravity to a collection pit. In the recovery process, the liquor is sieved during this transfer to remove particles and fibers originating from the hides. The liquor is then pumped to a treatment tank where magnesium oxide is added, with stirring, until the pH reaches at least 8. The stirrer is switched off and the chromium precipitates as a compact sludge of chromium hydroxide.
After settling, the clear liquid is decanted off. The remaining sludge is dissolved by adding concentrated sulfuric acid until a pH of 2. The liquor now contains chromium sulfate and is pumped back to a storage tank for reuse. In the manufacture of printed circuit boards, the unwanted copper is etched away by acid solutions as cupric chloride. As the copper dissolves, the effectiveness of the solution falls and it must be regenerated, otherwise it becomes a hazardous waste.
The traditional way of doing this was to oxidize the copper ion produced with acidified hydrogen peroxide. During the process the volume of solution increased steadily and the copper in the surplus liquor was precipitated as copper oxide and usually landfilled. The cleaner production process technology uses an electrolytic divided cell, simultaneously regenerating the etching solution and recovering the unwanted copper.
A special membrane allows hydrogen and chloride ions through, but not the copper. The copper is transferred via a bleed valve and recovered at the cathode as pure flakes of copper. The advantages of this cleaner production process are: improvement of the quality of the circuit boards, elimination of the disposal costs for the hazardous copper effluent, maintenance of the etching solution at optimum composition, recovery of pure copper for reuse, and zero discharge of hazardous effluent.
So the payback period for installation of this cleaner production technology was only 18 months. Southdown, Inc. According to Southdown, they are making a significant contribution to both the environment and energy conservation through the utilization of waste-derived fuels as a supplemental fuel source.
Cement kiln energy recovery is an ideal process for managing certain organic hazardous wastes. The burning of organic hazardous wastes as supplemental fuel in the cement and other industries is their engineering approach. Of course, by using hazardous waste fuels, the nation's hazardous waste including infections waste problem is at least partially solved with an economic advantage.
Decarbonization has been extensively studied by Dr L. Wang and his associates at the Lenox Institute of Water Technology, MA, United States, and has been concluded to be technically and economically feasible, in particular when the carbon dioxide gases from industrial stacks are collected for in-plant reuse as chemicals for tanneries, dairies, water treatment plants, and municipal wastewater treatment plants [22,23,42].
Greenhouse gases, such as carbon dioxide, methane, and so on, have caused global warming over the last 50 years. Average temperatures across the world could climb between 1. Carbon dioxide emissions from industry and automobiles are the major causes of global warming. According to the UN Environment Program Report released in February , the long-term effects may cost the world about billion US dollars a year in the future.
This is due to the following projected losses: a human life loss and property damages as a result of more frequent tropical cyclones; b land loss as a result of rising sea levels; c damages to fishing stocks, agriculture, and water supplies; and d disappearance of many endangered species. Technologically, carbon dioxide is a gas that can easily be removed from industrial stacks by a scrubbing process using any alkaline substances.
However, the technology for carbon dioxide removal is not considered to be cost-effective. Only reuse is the solution. The recovered proteins from both tanneries and dairies can be reused as animal feeds. In water softening plants using chemical precipitation processes, the stack gas can be reused as precipitation agent for hardness removal.
In municipal wastewater treatment plants, the stack gas containing carbon dioxide can be reused as neutralization and warming agents. Because a large volume of carbon dioxide gases can be immediately reused as chemicals in various in-plant applications, the plants producing carbon dioxide gas actually may save chemical costs, produce valuable byproducts, conserve heat energy, and reduce global warming problem [47]. By reviewing these case histories, one will realize that materials substitution is an important tool for cleaner production and, in turn, for industrial ecology.
Furthermore, materials substitution is considered a principal factor in the theory of dematerialization. The theory asserts that as a nation becomes more affluent, the mass of materials required to satisfy new or growing economic functions diminishes over time.
The complementary concept of decarbonization, or the diminishing mass of carbon released per unit of energy production over time, is both more readily examined and has been amply studied by many scientists. Dematerialization is advantageous only if using fewer resources accompanies, or at least leaves unchanged, lifetime waste in processing, and wastes in production [43].
It is hoped that through industrial ecology investigations, strategies may be developed to facilitate more efficient use of material and energy resources and to reduce the release of hazardous as well as nonhazardous wastes to our precious environment. Hopefully, we will be able to balance industrial systems and the ecosystem, so our agriculture and industry can be sustained for very long periods of time, even indefinitely, without significant depletion or environmental harm.
Integrating industrial ecology within our economy will bring significant benefits to everyone. Allen, D. Industrial ecology: a chemical engineering challenge. Ausubel, J. Cox, B. High-mileage precept still just a high-priced concept. Times Union, Automotive Weekly, February 22, ; 16 pp. Evers, D. Facility pollution prevention. Frosch, R. Toward the end of waste: reflections on a new ecology for industry. Daedalus ,. Strategies for manufacturing. Scientific American , Graedel, T.
Matrix approaches to abridged life cycle assessment. Hefele, W. Novel integrated energy systems: The case of zero emissions. Indigo Development. Klimisch, R. Designing the Modern Automobile for Recycling. Greening Industrial Ecosystems; Allenby, B. Krofta , M. Krofta, M. Total closing of paper mills with reclamation and deinking installations. Lafayette, IN, ; pp. Lovins, A. Lowe, E. Industrial ecology and industrial ecosystems. Cleaner Prod. ISBN Nagghappan, L. Master Thesis Wang, L. Ohrt, J.
Pratt, W. Renner, M. Rethinking the Role of the Automobile. Rittenhouse, D. Piecing together a sustainable development strategy. Tibbs, H. Industrial ecology: an environmental agenda for industry. Whole Earth Rev. US Congress. Waste Minimization Issues and Options. Facility Pollution Prevention Guide. Wang, L. Recycling and reuse of filter backwash water containing alum sludge.
Water Sewage Works , 5 , Continuous pilot plant study of direct recycling of filter backwash water. Water Works Assoc. Design and specifications of Pittsfield water treatment system consisting of air flotation and sand filtration. Water Treatment , 6, Innovative and cost-effective Lenox water treatment plant. Water Treatment , 7, DTT, 42 pp. DTT, pp. Management of Hazardous Substances at Industrial Sites.
Wernick, I. Materialization and dematerialization measures and trends. Daedalus , 3 , Searching for leverage to conserve forests: the industrial ecology of wood products in the US. Journal of Industrial Ecology , 1 3 , National Material Metrics for Industrial Ecology. Persistent contaminants in the environment affect human health and ecosystems. It is important to assess the risks of these pollutants for environmental policy.
Ecological risk assessment ERA is a tool to estimate adverse effects on the environment from chemical or physical stressors. It is anticipated that ERA will be the main tool used by the U. Toxicity bioassays are the important line of evidence in an ERA.
Recent environmental legislation and increased awareness of the risk of soil and water pollution have stimulated a demand for sensitive and rapid bioassays that use indigenous and ecologically relevant organisms to detect the early stages of pollution and monitor subsequent ecosystem change.
Aquatic ecotoxicology has rapidly matured into a practical discipline since its official beginnings in the s []. However, the experience gained with the bioassay of solid or slimelike wastes is as yet inadequate. At present the risk assessment of contaminated objects is mainly based on the chemical analyses of a priority list of toxic substances. This analytical approach does not allow for mixture toxicity, nor does it take into account the bioavailability of the pollutants present. In this respect, bioassays provide an alternative because they constitute a measure for environmentally relevant toxicity, that is, the effects of bioavailable fraction of an interacting set of pollutants in a complex environmental matrix [].
The use of bioasssay in the control strategies for chemical pollution has several advantages over chemical monitoring. First, these methods measure effects in which the bioavailability of the compounds of interest is integrated with the concentration of the compounds and their intrinsic toxicity. Secondly, most biological measurements form the only way of integrating the effects on a large number of individual and interactive processes.
Biomonitoring methods are often cheaper, more precise, and more sensitive than chemical analysis in detecting adverse conditions in the environment. This is due to the fact that the biological response is very integrative and accumulative in nature, especially at the higher levels of biological organization. This may lead to a reduction in the number of measurements both in space and time [12]. A disadvantage of biological effect measurements is that sometimes it is very difficult to relate the observed effects to specific aspects of pollution.
In view of the present chemicaloriented pollution abatement policies and to reveal chemical specific problems, it is clear that biological effect analysis will never totally replace chemical analysis. However, in some situations the number of standard chemical analyses can be reduced, by allowing bioeffects to trigger chemical analysis integrated monitoring , thus buying time for more elaborate analytical procedures [12].
This phase is characterized by USEPA as the identification of ecosystem components at risk and specification of the endpoints used to assess and measure that risk [13]. Assessment endpoints are an expression of the valued resources to be considered in an ERA, whereas measurement endpoints are the actual measures of data used to evaluate the assessment endpoint.
Toxicity tests can be divided according to their exposure time acute or chronic , mode of effect death, growth, reproduction , or the effective response lethal or sublethal Fig.
Other approaches to the classifications of toxicity tests can include acute toxicity, chronic toxicity, and specific toxicity carcinogenecity, genotoxicity, reproduction, immunotoxicity, neurotoxicity, specific exposure to skin and other organs. Unlike normal toxicity, the incidence of genotoxic effect is thought to be only partially related to concentration one-hit model. A toxicity test may measure either acute or chronic toxicity.
Acute toxicity is indicative for acute effects possibly occurring in the immediate vicinity of the discharge. This final chapter, entitled 'Treatment of power industry wastes' by Lawrence K. Wang, analyses the stream electric power generation industry, where combustion of fossil fuels coal, oil, gas, supplies heat to produce stream, used then to generate mechanical energy in turbines, subsequently converted to electricity. Wastes include waste waters from cooling water systems, ash handling systems, wet-scrubber air pollution control systems, and boiler blowdown.
Wastewaters are characterized and waste treatment by physical and chemical systems to remove pollutants is presented. Similar records in OSTI. GOV collections:. GOV Book: Handbook of industrial and hazardous wastes treatment. Title: Handbook of industrial and hazardous wastes treatment. Full Record Other Related Research. Abstract This expanded Second Edition offers 32 chapters of industry- and waste-specific analyses and treatment methods for industrial and hazardous waste materials - from explosive wastes to landfill leachate to wastes produced by the pharmaceutical and food industries.
Handbook of industrial and hazardous wastes treatment.
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