Biological disposal

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. 

Z. Evaporation. If the wastewater is in low volume and the waste material involatile, then evaporation can be used to concentrate the waste. The relatively pure evaporated water might still require biological treatment after condensation. The concentrated waste can then be recycled or sent for further treatment or disposal. The cost of such operations can be prohibitively expensive unless the heat available in the evaporated water can be recovered. 

In all types of biological processes, excess sludge is produced which must be disposed of. The treatment and disposal of sludge are major problems which can be costly to deal with. Anaerobic processes have the advantage here, since they produce considerably less sludge than aerobic processes (on the order of 5 percent of aerobic processes for the same throughput). 

Sludge disposal typically can be responsible for 25 to 40 percent of the operating costs of a biological treatment system. Treatment of sludge is aimed primarily at reducing its volume. This is so because the sludge is usually 95 to 99 percent water and the cost of disposal... 

Small quantities of spilled form amide can be washed away with plenty of water. Larger amounts should be absorbed appropriately or pumped into containers for proper disposal by incineration or biological degradation in a sewage water treatment plant. 

Emissions During Disposal and Incineration. The increasing use of modem incinerators to dispose of domestic waste results in complete combustion of plasticizers to carbon dioxide and water. The preponderance of plasticizer going into landfiUs is as plasticized PVC. Once a landfiU has been capped anaerobic conditions prevail and it is biologically relatively inactive. Under these conditions the main route by which organic components are removed from the landfiU contents is by ingress of water, extraction, and subsequent loss of water from the site to the environment. 

Sewer Disposal. Photoprocessing and printing wastes tend to be aqueous solutions that ate combined with other plant effluents and sent to the local sewer plant for treatment. The parameters of concern include silver, pH, and biological oxygen demand (BOD). BOD is a measure of how well a waste material degrades in the environment. Lower values ate preferred. Silver-bearing waste streams ate typically treated on-site, and the treated effluent is released to the drain. The printer usually receives a small cash credit for silver recovered. 

Incineration in an approved combustion plant is the preferred method of disposal. Wastewater from succinic acid processes is suitable for biological degradation by activated sludge (188). Polymeric sorbents (189) and ferric chloride treatment processes (190) can also be used for wastes containing... 

Clarifiers typically are used in chemical precipitation and biological treatment processes to remove precipitated metal soHds and suspended biological soHds. To prevent the sludge blanket from becoming too thick or heavy, part of the sludge blanket is removed continuously or intermittently from the system and thickened prior to disposal. 

Recovery of Riologieal Conversion Products Biological conversion produces that can be derived from solid wastes include compost, methane, various proteins and alcohols, and a variety of other intermediate organic compounds. The principal processes that have been used are reported in Table 25-64. Composting and anaerobic digestion, the two most highly developed processes, are considered further. The recovery of gas from landfills is discussed in the portion of this sec tion dealing with ultimate disposal. 

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... 

The general purpose of ultimate disposal of hazardous wastes is to prevent the contamination of susceptible environments. Surface water runoff, ground water leaching, atmospheric volatilization, and biological accumulation are processes that should be avoided during the active life of the hazardous waste. As a rule, the more persistent a hazardous waste is (i.e., the greater its resistance to breakdown), the greater the need to isolate it from the environment. If the substance cannot be neutralized by chemical treatment or incineration and still maintains its hazardous qualities, the only alternative is usually to immobilize and bury it in a secure chemical burial site. 

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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