Disposal methods

Costs of various waste disposal methods ate summarized in Table 5. 

Table 5. Estimated U.S. Processing Costs of Waste Disposal Method ...

Disposal of exhausted soHds can be easily overlooked at the plant design stage, particularly when these have no intrinsic value alternative disposal methods might include landfiU of inert material or incineration, hydrolysis, or pyrolysis of organic materials. Liquid, soHd, and gaseous emissions are aU subject to the usual environmental considerations. 

The specific design most appropriate for biomass, waste combustion, and energy recovery depends on the kiads, amounts, and characteristics of the feed the ultimate energy form desired, eg, heat, steam, electric the relationship of the system to other units ia the plant, iadependent or iategrated whether recycling or co-combustion is practiced the disposal method for residues and environmental factors. 

A significant concern in all nitration plants using mixed acids centers on the disposal method or use for the waste acids. They are sometimes employed for production of superphosphate ferti1i2ers. Processes have also been developed to reconcentrate and recycle the acid. The waste acid is frequently first stripped with steam to remove unreacted HNO and NO. Water is then removed by low pressure evapori2ation or vacuum distillation. 

Wastes contaminated with aniline may be Hsted as RCRA Hazardous Waste, and if disposal is necessary, the waste disposal methods used must comply with U.S. federal, state, and local water poUution regulations. The aniline content of wastes containing high concentrations of aniline can be recovered by conventional distillation. Biological disposal of dilute aqueous aniline waste streams is feasible if the bacteria are acclimated to aniline. Aniline has a 5-day BOD of 1.89 g of oxygen per gram of aniline. 

As part of TSCA, EPA can require the testing of any chemical if there is the possibiUty of an unreasonable risk to health or environment or if there is significant human or environmental exposure. If the substance poses an unreasonable risk, EPA can prohibit the manufacture, processing, or distribution of the substance limit the amount of the substance that can be manufactured, processed, or distributed prohibit a particular use for the substance limit the concentration of the substance during manufacture, processing, or distribution regulate disposal methods for the substance and require manufacturers to maintain records of process and to conduct tests to assure compliance with EPA rules. 

Transportation and Disposal. Only highly alkaline forms of soluble sihcates are regulated by the U.S. Department of Transportation (DOT) as hazardous materials for transportation. When discarded, these ate classified as hazardous waste under the Resource Conservation and Recovery Act (RCRA). Typical members of this class are sodium sihcate solutions having sihca-to-alkah ratios of less than 1.6 and sodium sihcate powders with ratios of less than 1.0. In the recommended treatment and disposal method, the soluble sihcates are neutralized with aqueous acid (6 Af or equivalent), and the resulting sihca gel is disposed of according to local, state, and federal regulations. The neutral hquid, a salt solution, can be flushed iato sewer systems (86). 

The individual membrane filtration processes are defined chiefly by pore size although there is some overlap. The smallest membrane pore size is used in reverse osmosis (0.0005—0.002 microns), followed by nanofiltration (0.001—0.01 microns), ultrafHtration (0.002—0.1 microns), and microfiltration (0.1—1.0 microns). Electro dialysis uses electric current to transport ionic species across a membrane. Micro- and ultrafHtration rely on pore size for material separation, reverse osmosis on pore size and diffusion, and electro dialysis on diffusion. Separation efficiency does not reach 100% for any of these membrane processes. For example, when used to desalinate—soften water for industrial processes, the concentrated salt stream (reject) from reverse osmosis can be 20% of the total flow. These concentrated, yet stiH dilute streams, may require additional treatment or special disposal methods. 

Drainage from active mining areas is considerably less than from inactive mines because of the disposal methods currently employed. Prior to discharge, Hquid effluents are limed and settled to precipitate metals as hydroxides. Elocculants are used to reduce the total suspended soHds and, in some instances, filtration of thickener overflow is practiced. 

Landfarming Landfarming is a waste-disposal method in which the biological, chemical, and physical processes that occur in the surface of the soil are used to treat biodegradable industrial wastes. Wastes to be treated are either apphed on top of the laud which has... 

For those waste streams that can impact public health or the environment (if mismanaged), provide a summary of the treatment and disposal methods (for example, solvents are incinerated or recycled, lab wastes are incinerated) used to manage them and identify the on-site or off-site facilities used. Is the disposal of the waste adequately documented (for example, retention of manifests, bills of lading or transfer notes) ... 

Table 28-2 lists some of the currently used pretreatments and ultimate disposal methods for hazardous wastes (6). Pretreatment refers almost entirely to thickening or dewatering processes for liquids or sludges. This process not only reduces the volume of the waste but also allows easier handling and transport. 

General precautions, disposal methods and statutory controls. 

When classified in terms of handling and disposal methods, solid wastes may comprise ... 

The effects from solid waste treatment and disposal depend upon the specific waste and the methods employed. The major disposal methods, depending upon the quantity and nature of the waste, are ... 

Landfill - Typically, the ultimate disposal method for solid wastes Is landfilling. Leaks from landfills need not be reported as a release because the amount of the toxic chemical in the landfill as already been reported as a release. 

Land treatmant/appllcatlon farming - Another disposal method is land treatment in which a waste containing a listed chemical is applied onto or incorporated into soil. While this disposal method is considered a release to land, any volatilization of listed chemicals into the air occurring during the disposal operation must be reported as a fugitive air release in Section 5.1 of Form R. 

Enter one of the following codes to identify the type of treatment or disposal method used by the off-site location for the chemical being reported. You should use more than one line for a single location when the toxic chemical is subject to different disposal methods the same location code may be used more than once. You may have this information in your copy of EPA Form SO, Item S of the Annual/Biennial Hazardous Waste Treatment, Storage, and Disposal Report (RCRA). Applicable codes for Part III, Section 6(c) are as follows ... 

Database containing information on over 400 contractors and the treatment, storage and disposal methods they offer. Treatment is broken into onsite and offsite and then by the following categories biological, chemical, physical, and thermal treatment. Menu driven. Available through cross talk for EPA Regional offices. 

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