Halogenated liquid organic wastes

Applicability/Limitations Liquid injection incineration can be applied to all pumpable organic wastes including wastes with high moisture content. Care must be taken in matching waste (especially viscosity and solids content) to specific nozzle design. Particle size is a relevant consideration so that the wastes do not clog the nozzle. Emission control systems will probably be required for wastes with ash content above 0.5 percent (particulate control) or for halogenated wastes (acid gas scrubbers). 

Like supercritical carbon dioxide, supercritical water is a very interesting substance that has strikingly different properties from those of liquid water. For example, recent experiments have shown that supercritical (superfluid) water can behave simultaneously as both a polar and a nonpolar solvent. While the reasons for this unusual behavior remain unclear, the practical value of this behavior is very clear It makes superfluid water a very useful reaction medium for a wide variety of substances. One extremely important application of this idea involves the environmentally sound destruction of industrial wastes. Most hazardous organic (nonpolar) substances can be dissolved in supercritical water and oxidized by dissolved 02 in a matter of minutes. The products of these reactions are water, carbon dioxide, and possibly simple acids (which result when halogen-containing compounds are reacted). Therefore, the aqueous mixture that results from the reaction often can be disposed of with little further treatment. In contrast to the incinerators used to destroy organic waste products, a supercritical water reactor is a closed system (has no emissions). 

Cleaning Up Place any dichloromethane-containing solutions in the ha-halogenated organic waste container and the other organic liquids in the organic solvents container. The aqueous layers should be diluted and neutralized with sodium carbonate before being flushed down the drain. After it is free of solvent, the sodium sulfate can be placed in the nonhazardous solid waste container. 

Cleaning Up Discard halogenated liquids in the halogenated organic waste container. Other solutions should be placed in the organic solvents container. 

Transfer the pot residues from the distillation of spearmint and/or caraway oil to the container for nonchlorinated organic wastes. After performing the prescribed tests on your distillate, put the isolated natural products into appropriately labeled containers. Place the dichloromethane solution from the bromine test for unsaturation in a container for halogenated organic liquids put the manganese dioxide from the Baeyer test for unsaturation in a container for heavy metals. Neutralize and then filter any excess 2,4-dinitrophenylhydrazine solution. Put the filter cake in the container for nonhazardous solids. Flush the filtrate as well as filtrates obtained from recrystallization down the drain. 

Hazardous waste liquid Waste liquid containing organic halogen or metal plating can be made nonhazardous. 

Solvent extraction generates no solid wastes. However, when the feed is a mixture of organic liquids that is treated for the recovery of just one component (e.g., halogenated hydrocarbons), economics may make the purification of the other mixture components impractical. The result is a waste stream needing disposal. 

Place the used filter papers in a container for nontoxic solid waste. Flush the acidic and basic filtrates down the drain. Pour any diethyl ether that has been isolated into a container for nonhalogenated organic liquids. Pour any dichloromethane that has been isolated into a container for halogenated organic liquids. 

Put the unused eluants containing only petroleum ether, acetone, and ethanol in the container for nonhalogenated organic liquids and any unused eluants containing chloroform in the container for halogenated organic liquids. Discard the dry chromatographic plates in the nonhazardous solid waste container. 

The presence and the relative amounts of non-combustibles, water, detergents, halogenated plastics, corrosive materials, and substances that may present a biological hazard in the waste may all affect the choice of incineration process and off-gas treatment, the overall process flow, and the materials used in the construction. Special attention shall be paid to the presence of spent ion exchange resins and organic liquids in the waste. 

Table 7.2 summarizes recommended procedures for waste treatment and disposal procedures, including those needed for waste containing two different types of hazardous materials. For example, the second line indicates that organic liquids containing both toxic chemicals and biological agents must first be disinfected by a halogen and then disposed of with toxic waste. 

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