Handling operations

In all HF processes, the HF leaves the furnace as a gas, contaminated with small amounts of impurities such as water, sulfuric acid, SO2, or SiF. Various manufacturers utilize different gas handling operations, which generally include scmbbing and cooling. Cmde HF is condensed with refrigerant, and is further purified by distillation (qv). Plant vent gases are scmbbed with the incoming sulfuric acid stream to remove the bulk of the HF. The sulfuric acid is then fed to the furnace. Water or alkah scmbbers remove the remainder of the HF from the plant vent stream. 

Iron ores of different characteristics and compositions can be blended to a more uniform composition. This can be accompHshed during handling operations involved in transporting ore to its point of use, or through special blending faciUties, such as stacking and reclaiming. 

An air valve, sometimes called the air-activated valve, is widely used for automated food handling operations. Although electronic or electric control boxes may be a part of the system, the valve itself generally is air-activated, and is more reflable than other types. Air-operated valves are used for in-place cleaning systems, and for the transfer and flow control of various products. 

In addition to encompassing all of the unit operations in the plant, the plant flow sheets may also include materials handling operations associated with the transport and storage of materials in and around the mill. Typically, flow sheets provide quantitative information regarding water and slurry flows, toimages, and assays. 

Truck unloading stations, barge, ship, or railcar loading and unloading stations grain and rack dryers and handling operations. Source Pahl, D., /. Air PoIIut. Control Assoc. 33, 468-482 (1983). 

Operating costs are best done in-house, because company personnel are familiar with corporate philosophies of staffing, maintenance, control laboratory operations. administrative requirements, and many other support aspects of running the business. If adequately staffed, the in-house study group should handle operating costs rather than try to teach a contractor company requirements. 

Health and Safety at Work etc. Act 1974 Management of Health and Safety at Work Regulations 1992 Management of Health and Safety at Work (Amendment) Regulations 1994 Manual Handling Operations Regulations 1992... 

Study of possible failures in handling operations 7 Benefits and practicality of evacuation... 

Cost-effective control of dust problems arising from bulk materials handling requires an initial examination of the overall handling operations. Factors influencing dust generation and dispersion must be understood in order to achieve a proper design. 

Make provision in your contract procedures for requiring customers to supply handling, operating, and maintenance instructions as necessary for any product they supply. 

Solid (particulate) emissions are produced from incomplete combustion of fuels, solids, drying operations, crushing and grinding operations, solids handling operations, and so on. The largest volume of emissions is from products of combustion (C02, CO, NOv, SO.v and particulates). Acid... 

Unexpected sources of ignition may lead to ignition of flammable materials during chemical processing or handling operations. 

Hazards attendant on the use of this powerful oxidant may in many cases be eliminated by substitution with sodium perborate (actually sodium borate hydrogen peroxidate) [1]. One of several wooden boxes of the peroxide (not clearly labelled as such) exploded with great violence dining handling operations. It seems likely that contamination with a combustible material, or possibly with moisture, had occurred [2],... 

This method of conveying now is being selected for an increasing number of industrial applications and products and hence, is playing a more vital and integral role in numerous bulk handling operations and processes. Some of the major reasons are listed below. 

For a dust ignition to occur, the suspended solids concentration must lie between lower and upper limits which vary from material to material and are influenced by subtle factors such as particle shape and size distribution. From the standpoint of assessing safety hazards in commercial and industrial operations, the lower explosive limit is the more important one. The rationale of this statement is that, if the possibility of exceeding the lower limit in a powder-handling operation can not be completely ruled out, then a hazard must be recognized and appropriate measures taken. Over the... 

Selected aspects of safe practice in solids handling are covered below. For additional information, refer to the rules for plant safety prepared by the Expert Commission for Safety in the Swiss Chemical Industry (ESCIS, 1988). While making no mention of fluidization, this source provides many practical suggestions for the avoidance of electrostatic ignition risks in powder handling operations. 

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