Chemical treating agents

The injection point of the sulfuric acid is in the pump bay, or as near as possible to water intake. The sulfuric acid pump is normally a motor-driven proportioning pump, and an electric motor is connected to a pH analyzer installed on the cooling water supply header so that the pump starts and stops, depending on the pH in the circulating water. Table 8.2 summarizes various chemical treating agents for cooling water towers. 

Table 8.2 Chemical Treating Agents for Cooling Water Towers...

The water treatment process, which may not be necessary in some plants and not connected with the chlor-alkali operation in others, may remove suspended solids, dissolved solids (primarily hardness elements), color bodies, and other oiganics. Suspended solids may be removed directly by sedimentation or with the aid of coagulants. Dissolved impurities are usually removed by precipitation with chemical treating agents. The solids generated are removed by sedimentation and filtration, often with the use of filter aids. All these additives increase the volume of waste. Control measures are quite similar to those used with similar process wastes. 

In chemical activation processes, the precursor is first treated with a chemical activation agent, often phosphoric acid, and then heated to a temperature of 450 -700 °C in an activation kiln. The char is then washed with water to remove the acid from the carbon. The filtrate is passed to a chemical recovery unit for recycling. The carbon is dried, and the product is often screened to obtain a specific particle size range. A diagram of a process for the chemical activation of a wood precursor is shown in Fig. 3. 

There are some requirements that oil spill-treating agents should fulfill. Chemical dispersants are often used to disperse spilled oils, which threaten to... 

M272 Water Testing Kit A lightweight portable kit used to detect and identify dangerous levels of common chemical warfare agents in raw and treated water in about seven minutes. It is a test water sampler and is not a continuous monitor. Each kit includes twenty-five tests for each agent. 

All effluents must be characterized in detail when treating agents contaminated with metals from disassembled chemical weapons (i.e., potential trace species and reaction by-products, such as nitrated hydrocarbons, partially oxidized products, and metals, must be identified) and their environmental impacts evaluated. 

Sulfur compounds are most commonly removed or converted to a harmless form by chemical treatment with lye. Doctor solution, copper chloride, or similar treating agents (Speight, 1999). Hydrorefining processes (Speight, 1999) are also often used in place of chemical treatments. When used as a solvent, naphtha is selected for its low sulfur content and the usual treatment processes remove only sulfur compounds. Naphtha, with its small aromatic content, has a slight odor, but the aromatics increase the solvent power of the naphtha and there is no need to remove aromatics unless odor-free naphtha is specified. 

DETAILS DMS is an extremely deadly and insidious chemical that was once considered for use as a chemical warfare agent. Initial exposure frequently produces no symptoms until the delay period has passed. This agent is ideal for treating enclosed spaces such as rooms or an automobile interior. Just figure the volume of the target area in cubic meters and double this amount to be sure. For example, a standard sized automobile has an interior volume of about five cubic meters. Therefore, five grams would... 

Laboratory studies indicate that aquathermolysis can be used to aid in the remediation of waste oils, chromium (Cr VI) and volatile organic compounds (VOCs) in contaminated soils and aquifers. Aquathermolysis is particularly useful in lowering the viscosity of oil and increasing its mobility to facilitate further treatment. Potential applications range from treating household and industrial refuse to destruction of chemical warfare agents. 

Ethylchloroacetate, Cl.CH2.C02.C2Hg raw 122.55 colorless pungent liq, sp gr 1.159 at 20°/4, fr p -26°, bp 144° flash p 54°C insol in w sol in ale, eth or benz. It can be prepd by the action of chloroacetyl chloride on ethanol or by treating chloroacecic acid with ethanol and sulfuric acid. It is used as solvent and as military poison gas. It wasnot described under Chemical Warfare Agents in Vol 2 of Encycl... 

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