WASTE-GENERATING PROCESSES

Code SIC group classification Waste-generating processes Expected specific wastes... 

The assessment of waste generation should start with the collection of information about the plant s waste-stream process and operation. A thorough understanding of the waste-generating process and streams is considered the best option for the reduction of this waste. 

Determine of modifications to a waste-generating process result in less leachable waste... 

Waste Minimization Analyze each waste-generating process for opportmiities to reduce the volume generated or ways to reuse or recycle wastes. Note that the waste minimization or pollution prevention opportmiities that are presented in this section can be used for this step. 

For solid wastes, since the main solid waste-generating process is drilling, the solid waste disposal processes are geared toward drilling waste. But solid waste is also generated during production and maintenance. These wastes are usually transported oflfsite. Other solid waste disposal methods include ... 

Facility Description—This section gives information about N Reactor operations such as facility process descriptions, waste-generating processes, Resource Conservation and Recovery Act of 1976 (RCRA), treatment, storage, and disposal (TSD) units at the N Reactor facility and other facilities outside of the N Reactor area. Figures 3-2 through 3-13 are sectional drawings of N Reactor Itself, which provide the reader with an Idea of the size and elevation of this structure. 

Radioactive and hazardous wastes were generated in various processes that supported N Reactor. In some cases, wastes were considered both hazardous and radioactive and were referred to as mixed wastes. The main waste-generating processes are discussed in the following subsections. The waste streams are summarized in Table 3-2. 

The assessment phase serves to identify the best options for minimizing waste through a thorough understanding of the waste-generating processes, waste streams, and operating procedures. Therefore, the initial tasks in the assessment phase include collecting information about the facility s waste streams, processes, and operations. 

Regulations. In order to decrease the amount of anthropogenic release of mercury in the United States, the EPA has limited both use and disposal of mercury. In 1992, the EPA banned land disposal of high mercury content wastes generated from the electrolytic production of chlorine—caustic soda (14), accompanied by a one-year variance owing to a lack of available waste treatment faciUties in the United States. A thermal treatment process meeting EPA standards for these wastes was developed by 1993. The use of mercury and mercury compounds as biocides in agricultural products and paints has also been banned by the EPA. 

With these waste-minimization techniques, methanol synthesis is relatively clean, and poses no unique environmental hazards. The need for environmental controls is more closely associated with the synthesis gas generation process. 

In-plant controls are perhaps the best approach to eliminate waste generation and pollution problems, and many times good payback exists on recovery of products lost because of poor process controls. If the production department is responsible for the generation and in-plant control of wastes, this will help ensure that initial standards for water use and process loss are reasonable and that they are maintained (33). 

Ereduc tion of a product or service must be evaluated over its entire istoiy or life cycle. This life-cycle analysis or total systems approach (Ref. 3) is crucial to identifying opportunities for improvement. As described earher, this type of evaluation identifies energy use, material inputs, and wastes generated during a products hfe from extraction and processing of raw materials to manufacture and transport of a product to the marketplace and finally to use and dispose of the produc t (Ref. 5). 

Assessment Phase The assessment phase aims to collect data needed to identify and analyze pollution-prevention opportunities. Assessment of the facility s waste-reduction needs includes the examination of hazardous waste streams, process operations, and the identification of techniques that often promise the reduction of waste generation. Information is often derived from obsei vations made during a facihty walk-through, interviews with employees (e.g., operators, line workers), and review of site or regulatory records. One professional organization suggests the following information sources be reviewed, as available (Ref. 7) ... 

Waste Reduction Processes can be redesigned to reduce the amount of waste generated. For example, transfer hnes between processes can be Blown clear pneumaticaUy to drive liquid into the Batch mix tank. 

Identification of Waste Constituents In any processing (and disposal) scheme, the key item is knowledge of the characteristics of the wastes to be handled. Without this information, effective processing or treatment is impossible. For this reason, the characteristics of the wastes must be known before they are accepted and hauled to a treatment or disposal site. In most states, proper identification of the constituents of the waste is the responsibility of the waste generator. 

A systematic program should he undertaken to examine all sources of waste production and to develop alternative operations and processes to reduce waste generation. 

Table 16.5 Examples of hazardous gases generation from waste pretreatment processes ...

---