Dust control material

Dust control material is applied to calcined coke to help maintain a dnst-free environment. It adds weight to the coke and can have a negative effect on the quality of carbon and graphite artifacts made from the treated coke. Hence, a maximum amount may be specified. 

In the test method (ASTM D4930), a weighed dry representative coke sample 6.3 mm in maximum size is extracted using methylene chloride in a Soxhlet apparatus. The mass of the residue remaining after extraction and evaporation of the solvent is the mass of the dnst control material. This test method is limited to those materials that are solnble in a solvent (e.g., methylene chloride) that can be used in a Soxhlet extraction type of apparatns. Tolnene and methyl chloroform have also been found to give resnlts eqnal to those of methylene chloride. 

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There are two sources of interferences in this test method—moisture and particle size. Moisture increases the mass loss, the moisture-free sample weight is decreased by the amount of moisture actually present in the test sample, and the particle size range of the analysis sample affects the volatile matter. The coarser the sample, the lower the reported yield of volatile matter. The method is not satisfactory for determining the content of dust control material, and samples with a thermal history above 600°C (1112°F) are excluded from this test. 

The health and safety issues outlined herein for particleboard also apply to MDE. A special note should be made of the fact that, because the MDF raw material is of dry fiber base, there exists in MDF a large component of very small, broken, dust-like wood fibers. These contribute to the dust concerns in the manufacturing areas, requiring exceUent dust-control systems, good housekeeping, and personal protection. 

Sealant Manufacturing. Most sealants use mineral-based fillers which may contain small amounts of crystalline siHca. If crystalline siHca is present, dust control is important to prevent inhalation of these particles. Crystalline siHca is a known cause of siHcosis, a debiHtating disease of the lung. Another common safety concern in sealant manufacturing is the use of flammable materials. Not all sealants use flammable ingredients, but for those that do, proper inerting and grounding are needed to prevent potential explosions. 

This discussion will address needs, applications, performance characteristics, and design considerations for LVHV exhaust ventilation. The applications are primarily for dust control. LVHV systems can be effective for protecting workers from dust exposures and for recovering valuable process materials. The equipment, excepting the nozzles, involves technology that is the same as for large central vacuum cleaning systems. 

This Chapter provides information on available certified reference and quahty control materials relevant for use in the measurement of airborne contaminants in occupational hygiene. The majority of measurements made in this area worldwide are solvents, dust (total, respirable), elements, oil mist, quartz, fiber identification (asbestos, man-made fibers), mists and gases. 

Another excipient used in feed additive premixes is a diluent used to dilute or standardize activity. Diluents are similar in composition to grain carriers, except the particle size is generally smaller. No attempt is made to absorb the active drug to the individual particles of the diluents. If a liquid is used it is mainly for dust control. A diluent is considered for use when the level of the active ingredient components in the premix approaches or exceeds 50% of the product or when two or more active components vary greatly from one another in density [13]. Examples of diluent materials are ground limestone, sodium sulfate, kaolin, corn cob flour, and ground oyster shells. 

Extraction of dust via a network of branched ducts, where the particulates are transported under vacuum conditions. Some common examples include the control of dust in materials... 

A HIGH DRAW TENSION O LOW QUALITY STARTING TUBE DUST IN DRAWING ENVIRONMENT WELL-CONTROLLED MATERIALS AND PROCESSING... 

Because of the nondrifting qualities of the granular materials, they can be applied under conditions of greater air movement than fine sprays or dusts. This means that airplanes are not limited to operating a few hours at dawn or dusk but can be used many more hours a day. This in turn should permit more efficient use of airplanes. Each of the above factors should result in lower costs of application of mosquito control materials and make practical the use of control measures over greater areas. 

On a site, materials handling and dust control are always the issues which must be faced. Because the site contains MPA which can pose both an environmental and a direct health risk, the entire excavated site will have to be wet down regularly for dust control, and despite the mud problems this creates, water and mnoff from the site must be collected, tested, treated, prior to its release. The same thing must happen for the treated soils. 

For direct drying of liquids, slurries, and pastes, drum dryers are the only competition for spray dryers, although fluidized bed dryers sometimes can be adapted to the purpose. Spray dryers are capable of large evaporation rates, 12,000-15,000 lb/hr or so, whereas a 300sqft drum dryer for instance may have a capacity of only 3000 lb/hr. The spherelike sprayed particles often are preferable to drum dryer flakes. Dust control is intrinsic to spray dryer construction but will be an extra for drum dryers. The completely enclosed operation of spray dryers also is an advantage when toxic or noxious materials are handled. 

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