Industrial waste auditing

The audit program employs contractors for completion of waste audit studies of specific industries. After the studies are completed a final report is then generated, containing recommendations and conclusions for waste reduction. The final report is used as a source document for developing the fact sheets and the WRAM for use by small quantity generators (SQG). Currently 19 different industry waste audit studies have been completed. 

The principal intent of a waste audit is to critically assess various inputs, processes, and outputs to find methods and practices for minimizing waste and reducing the resource consumption in a sustainable and environmentally benign way without compromising the commercial interest of the company. The waste audit phase would typically be a data collection and information synthesis phase that explores the current situation. Traditionally, an industrial waste audit also develops a list of waste minimization options and undertakes some preliminary technical and economic feasibility studies on the identified options to recommend about these opiions. 

C. Visvanathan (Asian Institute of Technology in Klongluang Pathumthani, Thailand), who contributed the chapter on Industrial Waste Auditing, writes, As new opportunities to reuse and recycle industrial waste are explored, complete prohling of waste is essential. The lirst step to exploring such an opportunity is to undertake comprehensive waste auditing. This chapter discusses industrial waste audit techniques in an easy, simple, step-by-step approach that can even be understood by those who are new to the subject."... 

DHS. 1989. Waste Audit Study Fabricated Metal Products Industry. Department of Health Services, Toxic Substances Control Division, Alternative Technology Section. Prepared by Jacobs Engineering Group. Contract No. 87-T0096. 

The waste audit program is Intended to provide assistance to California s small quantity generators of hazardous waste. This is accomplished by issuing contracts to evaluate waate reduction opportunities in industries typically comprised of small to medium businesses. Waste-generating operations are studied to identify potentials for reducing waste, recycling or recovering resources, or alternative treatment measures. The economic feasibilities of the various alternatives are analyzed, and the study results are compiled in a final waste audit report. 

PRC Environmental Management, Inc. 1988. Waste Audit Study—Metal Finishing Industry. United States Environmental Protection Agency and California Department of Health Services, San Francisco, California. 

Industrial Waste Treatment Characterizing Waste Streams Evaluating Waste Reduction Opportunities Waste Reduction Audit Checklist... 

Industry Observations Wasle Management Concerns Technology Development and Transfer Management Involvement Waste Audit Results... 

Mercury is one of a number of toxic heavy metals that occur in trace amounts in fossil fuels, particularly coal, and are also present in waste materials. During the combustion of fuels or wastes in power plants and utility boilers, these metals can be released to the atmosphere unless remedial action is taken. Emissions from municipal waste incinerators can substantially add to the environmental audit of heavy metals, since domestic and industrial waste often contains many sources of heavy metals. Mercury vapor is particularly difficult to capture from combustion gas streams due to its volatility. Some processes under study for the removal of mercury from flue gas streams are based upon the injection of finely ground activated carbon. The efficiency of mercury sorption depends upon the mercury speciation and the gas temperature. The capture of elemental mercury can be enhanced by impregnating the activated carbon with sulfur, with the formation of less volatile mercuric sulfide [37] this technique has been applied to the removal of mercury from natural gas streams. One of the principal difficulties in removing Hg from flue gas streams is that the extent of adsorption is very low at the temperatures typically encountered, and it is often impractical to consider cooling these large volumes of gas. 

Waste Audits The company must identify the processes, the products, and the waste streams in which (hazardous) chemicals are used. Mass balances of specific (hazardous) chemicals will help to identify source reduction opportunities. Engineering interns could be very valuable in conducting such audits. An outside person can achieve significant progress in this area as well, due to the fact that he or she may be able to cut through some of the management and personnel barriers of the industry. 

Once a waste-minimization program is set to be undertaken, the physical work starts with a series of detailed surveys of ongoing activities inside the industry, starting from raw material entering the premises to finished products and byproducts (including wastes). These audits can be termed as waste audits or waste-minimization audits. The principal intent of such audits is to critically assess various inputs, processes and outputs to find methods and practices for... 

Phases I to n have covered planning and undertaking waste audit, resulting in the preparation of a material balance for each unit operation. Phase IV represents the interpretation of the material balance to identify process areas or components of concern. Figure 4 represent a material balance algorithm for the textile industry in establishing waste reduction options. 

Industrial waste is an important source of energy and material hence, many industries are engaged in extensive environmental audits and evaluate their own waste management activities. There are large economic as well as environmental benefits when appropriate waste management is implemented. The existing system within industry requires an energy-optimisation alternative for the plastics waste... 

UNIDO, Waste Reduction Auditing Manual, US/GLO/91/103, United Nations Industrial Development Organization, Industrial Sectors and Environment Division, Vienna, Austria, 1991. 

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