Abstract: The specification discloses a process for the treatment of waste gas containing hydrogen chloride wherein the gas is at an elevated temperature in the range of from about 300.degree. F. to about 3000.degree. F. and is produced from the thermal decomposition of material contaminated with hazardous chlorinated organic compounds. The waste gas is contacted in a reaction unit with an alkaline brine solution under conditions such that hydrogen chloride in the waste gas reacts with the alkali to form a chloride salt and water. The heat of the gas evaporates water from the solution to maintain the salt concentration sufficiently high to cause the formation of salt crystals in the solution. The gas is conducted from the reaction unit following contact with the solution under conditions such that the gas includes water evaporated from the solution.

Abstract: A thermal treatment process employs an indirectly fired rotary kiln in which matrix material contaminated with organic substances such as dioxins, PCBs, PAHs, fuel oils, and the like is heated as the material is advanced through the kiln to cause components of the organics to be released as vapor. Purge gas of low oxygen content is conducted through the kiln at a relatively low velocity of from about 0.5 ft./sec. to about 10 ft./sec. to gently sweep the vaporized components of the organic substances from the kiln and to minimize the entrainment of solid particulates, and to produce an off gas mixture including the vaporized components. The off gas is conditioned after removal from the kiln to render it acceptable for discharge to the atmosphere. The oxygen concentration in the kiln is maintained at a sufficiently low level to substantially prevent combustion of the vaporized organic components in the kiln.

Abstract: A system including a method and apparatus for treating waste containing organic contaminants which includes a direct fired, countercurrent, rotary kiln providing a soaking zone having an oxidizing atmosphere through which the materials being treated are passed after the unwanted organics are removed, and a secondary combustion chamber for oxidizing gases containing vaporized or pyrolyzed organics in which the organics are burned and are subjected to high temperatures for a holding time sufficient to effect destruction of the organic contaminants. The system includes means to minimize off-gas so as to make possible a reduction in size of the equipment employed.

Abstract: The invention is an apparatus for aerobically biodegrading an organic compound such as a petroleum product which is contaminating a particulate solid such as soil and a process for employing the apparatus. A preferred embodiment comprises a pit lined with an impermeable liner in which gas distributing means and contaminated soils are distributed as alternate layers and air is urged into the gas distributing means.

Abstract: A method is disclosed for the monitoring and control of a microbial population in a biotechnological system. The method involves the identification of at least one critical subpopulation and determining the optimal level for said subpopulation. A controlled variable is determined which can be adjusted to alter the level of the subpopulation. The method employs nucleic acid hybridization in the microbial population. This involves the preparation of a labelled probe from nucleic acid having a nucleotide sequence substantially complementary to a nucleotide sequence in the nucleic acid in the subpopulation. A representative sample of the microbial population is obtained and treated to free nucleic acids and to denature double-stranded nucleic acids. The resulting sample nucleic acids are contacted with the labelled probe under appropriate conditions to form duplexes.

Abstract: A system including a method and apparatus for treating waste containing organic contaminants which includes a direct fired, countercurrent, rotary kiln providing a soaking zone having an oxidizing atmosphere through which the materials being treated are passed after the unwanted organics are removed, and a secondary combustion chamber for oxidizing gases containing vaporized or pyrolyzed organics in which the organics are burned and are subjected to high temperatures for a holding time sufficient to effect destruction of the organic contaminants. The system includes means to minimize off-gas so as to make possible a reduction in size of the equipment employed.

Abstract: A process in which spent catalyst from chlorofluorocarbon production is treated to detoxify the catalyst for safe disposal or reprocessing. The spent catalyst includes antimony and arsenic halides, halogenated organic liquids, and has an upper liquid portion and a lower sludge or semisolid portion. The processing of both the liquid and sludge portions includes hydrolyzing the catalyst in an aqueous solution of ferric chloride resulting in formation of a ferric ion/fluoride ion complex in addition to insoluble compounds, and neutralizing the reaction mass following hydrolysis with an aqueous suspension of calcium hydroxide. The volatile organics are stripped from the neutralized reaction mass and collected for reuse or disposal. The reaction mass is dried to yield the insoluble compounds in a solid form for subsequent reprocessing or disposal.

Abstract: The present invention is a method for distributing a colloid-free, aqueous solution containing a peroxygen compound in a particulate matter containing clay without causing the clay to swell. It has been found that hydrogen peroxide alone causes swelling of clays. It is well-known that monovalent ions cause clays to disperse and swell. It is unexpected to find that perborate and persulfate anions do not cause clays to swell, even in the presence of sodium ions. The process is useful for enhancing the biodegradation of contaminants in clayey soils or for winning mineral values from clayey ore deposits.

Abstract: The present invention provides a composition of nutrients and a method using such a composition to stimulate the growth of aerobic bacteria, and particularly bacteria capable of biooxidizing contaminants in a subterranean formation.