Flammability considerations

Another class of processes where it is advantageous to keep the reactants separated from each other, except within the catalyst pores, is oxidation of light gaseous hydrocarbons (e.g., ethene, propene, butene). Conventionally these processes are carried out in multi-tubular fixed-bed reactors (see, for example, Fig. 20). Flammability considerations usually restrict the feed mixture composition. By adopting the concept of a multi-tubular cooled catalytic membrane reactor (with inclusion of heat pipes ), with reactants kept separate, we should be able to avoid any flammability constraints. 

Solution adhesives consist of solid rubber dissolved in a solvent such as toluene, naphtha, or trichloroethane. The solvent used will depend on the drying and flammability considerations in the application. Milled raw rubber can be shredded and agitated in the solvent until a clear solution is obtained. Other components are added at this stage and mixed uniformly. Alternatively, the solid rubber can be compounded with other components and the mix dissolved in the solvent. 

Besides, the usage of halogen-replaced bisphenols and dicarboxylic acids for synthesizing polyesters of lowered flammability considerably... 

Besides, the usage of halogen-replaced bisphenols and dicarboxylic acids for S5rnthesizing polyesters of lowered flammability considerably increases the cost of the latter. Consequently, the aromatic inhibiting flame additions are necessary for creating thermally and fire resistant pol5mieric materials. The introduction of such agents in small amounts would not diminish properties of polyesters. 

Fixed bed reactors are limited by flammability considerations to about 1.2 to 1.8 mol% butane in the feed, as the butane and air are premixed outside the reactor. The fluidized bed can operate with up to possibly 5 mol% butane in the feed because butane is sparged separately into the bed and the mass of catalyst acts as a heat sink. The higher butane-to-air feed ratio reduces the size of the downstream gas handling section of the process, reducing the capital cost. 

Potential health and safety problems of acryflc polymers occur in their manufacture (159). During manufacture, considerable care is exercised to reduce the potential for violent polymerizations and to reduce exposure to flammable and potentially toxic monomers and solvents. Recent environmental legislation governing air quality has resulted in completely closed ketde processes for most acryflc polymerizations. Acryflc solution polymers are treated as flammable mixtures. Dispersion polymers are nonflammable. 

The various fumigants often exhibit considerable specificity toward insect pests, as shown in Table 8. The proper choice for any control operation is determined not only by the effectiveness of the gas but by cost safety to humans, animals, and plants flammabdity penetratabdity effect on seed germination and reactivity with furnishings. The fumigants may be used individually or in combination. Carbon tetrachloride has been incorporated with carbon disulfide, ethylene dichloride, or ethylene dibromide to decrease flammability, and carbon dioxide is used with ethylene oxide for the same purpose. 

The test shall be hydrostatic, using water, with the following exceptions. If there is a possibility of damage due to freezing or if the operating fluid or piping material would be adversely affected by water, any other suitable hquid may be used. If a flammable hquid is used, its flash point shall not be less than 50°C (120°F), and consideration shall be given to the test environment. 

When reading an accident report, look for the things that are not said. For example, a gland leak on a liquefied flammable gas pump caught fire and caused considerable damage. The report drew atten-... 

It should not be assumed that just because there is no seal, sealless pumps are always safer than pumps with seals, even with the advanced technology now available in sealless pumps. Use sealless pumps with considerable caution when handling hazardous or flammable liquids. 

If the density of a vapor is greater than air, as is the case with most gases and vapors encountered in industry, flammable concentrations may collect at low levels, such as at floor level or in basements, and can travel considerable distances to a source of ignition and the flames will then flash back. 

Safety Considerations Design and location of storage tanks, vents, piping, and connections are specified by state fire marshals, underwriters codes, and local ordinances. In NFPA 30, Flammable and Combustible Liquids Code, 1993 (published by the National Fire Protection Association, Quincy, Mass.), liquid petroleum fuels are classified as follows for safety in handhng ... 

For reactors containing flammable liquids, where the reactor design pressure is insufficient to contain a deflagration, consideration should be given to providing an inert gas blanket (usually nitrogen). 

Regulations and specifications. There may be international (e.g. EU), national or local regulations concerning the use of materials. These may be with respect to factors such as flammability, contact with foodstuffs, environmental considerations and medical criteria. 

An elementary introduction to chemistry is given in Chapter 3 this serves only to provide background and for more advanced consideration reference will be necessary to specific text books, e.g. as listed in the Bibliography. A brief discussion of the relevance of physicochemical principles to hazard identification is given in Chapter 4. Relevant toxic and flammable properties, and summaries of appropriate precautions to cater for them during handling, use and disposal, are provided in Chapters 5 and 6, respectively. Reactive hazards are discussed in Chapter 7. The special problems with cryogenic materials and chemicals under pressure, typified by compressed... 

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