Chlorinated solvents burning

Volatile organic compounds (VOC) contribute to the formation of tropospheric ozone (summer smog). Certain halogenated hydrocarbons (e.g. CFCs) also destroy the stratospheric ozone layer. Chlorinated solvents are hazardous to water and, if disposed of incorrectly (e.g. burning), may emit highly toxic substances (e.g. dioxins). 

Waste oil Used oil which contains in excess of 1000 ppm chlorine, 5 ppm arsenic, 2 ppm disposal cadmium, 10 ppm chromium, 100 ppm lead, or having a flash point of less than 40°C is considered to be hazardous waste and cannot be burned for energy recovery or used in any way to produce fuel. Waste oil containing more than 1000 ppm chlorine is considered to be contaminated with chlorinated solvents or PCB and is designated as hazardous waste. 

It has extremely low water vapor transmission, even with extruded thin transparent film. Chemical resistance is generally good, although not comparable to PTFE and other fluoroplastics. Chlorinated solvents, in particular, can affect PCTFE, and it can be subjected to stress cracking at elevated temperatures. The presence of chlorine atoms, used to enhance flame retardancy, keeps PCTFE in the non burning category with PTFE. It causes, however, a serious increase in dielectric losses, particularly at high frequencies. 

General guidelines for initial disposal (D, dilute with water neutralize, if necessary, with an appropriate inorganic acid or base and flush down drain C, chlorinated solvent disposal NC, non-chlorinated solvent disposal S, solid disposal in accredited landfill site or burned in a chemical incinerator R, refer to local safety officer)... 

Phosgene was originally manufactured as a war gas. It is now used in the manufacture of dyes, resins, and pesticides. It is also commonly produced when chlorinated compounds are burned, such as in a fire, or in the process of welding metal that has been cleaned with chlorinated solvents. 

Chemical properties Polycarbonate is a generic term for polymers that contain carbon acid esters in the chains of their molecules. Pale yellow colour on manufacture due to impurities in the monomers (bisphenol-A), which is masked with blue dyes. PC is a polar polymer and is dissolved by chlorinated solvents. Almost self-extinguishing on burning. Poor resistance to chemicals and weathering. 

Incineration to waste provides a last resort for environmentally acceptable disposal. Since this has often been necessary for burning used chlorinated solvent residue, the incinerator needs to be equipped with sophisticated scrubbing facilities. 

Provided that the solvent/oil mixture has not been contaminated with high-boiling chlorine compoimds it should be possible to use the residue from recovery as a fuel. However, trichloroethylene is very effective for cleaning chlorinated paraffin waxes from equipment and the chances of ending up with a residue containing too much chlorine to burn in anything but a chemical incinerator are appreciable. 

There are two types of incinerators used predominantly for incineration of hazardous waste. The first type is the rotary kiln, which operates at temperatures of approximately 2300 "F. More hazardous wastes are burned in this type of kiln than any other and it is the one for which most tests on destruction efficiencies have been done. A second type is the cement kiln, which is now being used more often. The temperature of the cement kiln reaches 3000 "F. The hazardous waste is blended with the fuel and used in the making of cement. By modifying the fuel blend, it is possible to obtain efficient destruction, even for chlorinated solvents. 

CH2C1 CH2C1. Colourless liquid with an odour like that of chloroform b.p. 84 C. It is an excellent solvent for fats and waxes. Was first known as oil of Dutch chemists . Manufactured by the vapour- or liquid-phase reaction of ethene and chlorine in the presence of a catalyst. It reacts with anhydrous ethano-ales to give ethylene glycol diethanoate and with ammonia to give elhylenediamine, these reactions being employed for the manufacture of these chemicals. It burns only with difficulty and is not decomposed by boiling water. 

Entry into a tank that has contained any chlorinated or any easily evaporated solvent requires special procedures to ensure worker safety. The heavier vapors tend to concentrate in unventilated spaces. The proper tank entry procedure requires positive ventilation, testing for residue solvent vapor and oxygen levels, and the use of respiratory equipment and rescue harness. Monitoring the tank from outside is also important. The use of an appropriate gas mask is permissible in vapor concentrations of less than 2% and when there is no deficiency of atmospheric oxygen, but not for exposures exceeding one-half hour. Skin exposure to 1,1,1-trichloroethane can cause irritation, pain, bHsters, and even burning. Eye exposure may produce irritation, but should... 

PS is soluble in aromatic hydrocarbon solvents and is resistant to aqueous solutions of nonoxidizing acids, alkalis, and salts. It is attacked by chlorine and oxidizing acids, such as 25% nitric and 95% sulfuric adds. In the absence of flame retardants, this aromatic hydrocarbon polymer burns readily and produces considerable amounts of black smoke. The latter is due to the formation of highly colored cyclic byproducts as the PS is burned. 

A paste of zinc powder and carbon tetrachloride (with kieselguhr as thickener) will readily burn after ignition by a high-temperature primer [1]. Intimate mixtures of chlorinated rubber with powdered zinc (or its oxide) in presence or absence of hydrocarbon or halocarbon solvents react violently or explosively at about 216°C... 

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