Hazard control inerting

Inherently safer approaches to dust explosion hazard control include inerting and building equipment strong enough to contain an explosion. 

Inert gas-filled motors can also be used in refineries and chemical plants, but their applications are limited. They have tightly fitted covers and oil seals around the shaft to minimize gas leakage, are continually pressurized with an inert gas or instrument air, and are equipped with an internal air-to-water heat exchanger. Inert gas-filled motors are suitable for any hazardous location but require auxiliaries such as cooling water, gas pressurizing system, and control accessories. 

Although microwave-heated organic reactions can be smoothly conducted in open vessels, it is often of interest to work with closed systems, especially if superheating and high-pressure conditions are desired. When working under pressure it is strongly recommended to use reactors equipped with efficient temperature feedback coupled to the power control and/or to use pressure-relief devices in the reaction vessels to avoid vessel rupture. Another potential hazard is the formation of electric arcs in the cavity [2], Closed vessels can be sealed under an inert gas atmosphere to reduce the risk of explosions. 

Detonation arresters are typically used in conjunction with other measures to decrease the risk of flame propagation. For example, in vapor control systems the vapor is often enriched, diluted, or inerted, with appropriate instrumentation and control [5]. In cases where ignition sources are present or predictable (such as most vapor destruct systems), the detonation arrester is used as a last-resort method anticipating possible failure of vapor composition control. Where vent collection systems have several vapor/oxidant sources, stream compositions can be highly variable and this can be additionally complicated when upset conditions are considered. It is often cost-effective to perform hazard analyses such as HAZOP or fault... 

Storage tanks Dikes Emergency valves Inspections Procedures Specifications Limitations Design separation, inerting, materials of construction Capacity and drainage Remote control hazardous materials Flash arresters and relief devices Contamination prevention, analysis Chemical, physical and quality stability Temperature, time and quantity... 

The readers are referred to new references (46-49) and US governmental reports (50-59) for modem site remediation technologies. For completion of a successful site remediation project, all aspects of environmental pollution control (air, noise, water, and soil) must be considered. Oxidation chemically converts hazardous contaminants to non-hazardous or less toxic compounds that are more stable, less mobile, and/or inert. The oxidizing agents most commonly used are ozone, hydrogen peroxide, hypochlorites, chlorine, and chlorine dioxide (46,47). Figme 3 shows a typical chemical oxidation system for site remediation. 

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