Solvents flammability

Chlorobenzenes are generally considered nonflammable materials with the exception of monochlorobenzene, which has a flash point of 34.5°C and is a flammable solvent based on DOT standards. 

Explosible dusts can also be changed into mixtures which are no longer explosible by the addition of inert dusts (e.g., rock salt, sodium sulrate). In general, inert dust additions of more than 50 wt % are necessary here. It is also possible to replace flammable solvents and cleaning agents by nonflammable halogenated hydrocarbons or water, or flammable pressure transmission fluids by halocarbon oils. 

Requiring nitrogen inerting when pouring dry solids into flammable solvents... 

Using a closed charging system rather than pouring dry powders into flammable solvents directly via an open manhole... 

Performing an electrostatic hazard review of the whole plant and all the processes whenever powders and flammable solvents are used... 

Design where natural circulation is sufficient to prevent accumulation of flammables Eliminate flammable solvent (e.g., substitute water-based solvent)... 

Batch dryer operation resulting in a high peak evaporation rate of flammable solvent causing buildup of flammables. Possibility of fire/explosion. 

The drying of flammable solvents with sodium or potassium metal and metal hydrides poses serious potential fire hazards and adequate precautions should be stressed. 

Small concentrations of volatile components in a liquid mixture may accumulate in the vapor space of a container over time and appreciably reduce the flash point relative to the reported closed-cup value. This may be the result of degassing, chemical reaction or other mechanism. An example is bitumen [162]. Similarly, if a tank truck is not cleaned between deliveries of gasoline and a high flash point liquid such as kerosene or diesel oil, the mixture might generate a flammable atmosphere both in the tmck tank and the receiving tank. Contamination at the thousand ppm level may create hazards (5-1.4.3 and 5-2.5.4). Solids containing upward of about 0.2 wt% flammable solvent need to be evaluated for flammable vapor formation in containers (6-1.3.2). 

In the laboratory, a range of slush baths may be used for speciality work. These are prepared by cooling organic liquids to their melting points by the addition of liquid nitrogen. Common examples are given in Table 8.2. Unless strict handling precautions are instituted, it is advisable to replace the more toxic and flammable solvents by safer alternatives. 

COSMETICS, UITH FLAMMABLE SOLVENTS COUMAFURYL see FUMARIN CQUMAPHOS... 

PERFUMERY PRODUCTS, WITH FLAMMABLE SOLVENT PERMANGANATES, INORGANIC, n.o.s. 

Inherent—Eliminating the hazard by using materials and process conditions which are nonhazardous e.g., substituting water for a flammable solvent. 

It may even be possible to eliminate solids handling by processing in a solution. However, this may require an assessment of the hazards of a toxic or flammable solvent in a process compared to the hazards of the solvent-free process. 

A reaction vessel explosion at BASF s resins plant in Cincinnati (July 19, 1990) killed one and injured 71. The BASF facility manufactures acrylic, alkyd, epoxy, and phenol-formaldehyde resins used as can and paper-cup liner coatings. The explosion occurred when a flammable solvent used to clean a reaction vessel vented into the plant and ignited. The cleaning solvent that was not properly vented to a condenser and separator, blew a pressure seal, and fdled the 80-year-old building with a white vapor cloud. 

CFCs have been widely used as cleaning solvents, as they are nonflammable and their toxicity is low. Now, flammable solvents are coming back into favor. A news item from a manufacturer described "a new ozone-friendly cleaning process for the electronics industry, which "uses a unique hydrocarbon-alcohol formulation. It did not remind readers that the mixture is flammable and that they should check that their equipment and procedures are suitable. 

Many explosions, some serious, have occurred in centrifuges handling flammable solvents because the nitrogen blanketing was not effective. 

On all centrifuges that handle flammable solvent, the oxygen content should be continuously monitored. At the very least, it should be checked every shift with a portable analyzer. In addition, the flow of nitrogen should be adequate, clearly visible, and read regularly. 

All such resin solutions are based on flammable solvents and are becoming increasingly less acceptable on health and safety grounds. There is therefore increased interest in water-based polymer dispersion floor sealers, but, to date, none offer the same improvement to flooring performance that some of the resin solutions can provide. 

There are other more recent examples though. In one laboratory, flammable solvents had been used in such small quantities that they required no special storage. As their use of solvents increased, however, there were eventually five-gallon cans of ether casually stored in one comer of a room. When a routine inspection by the fire department uncovered this hazard, the laboratory was forced to install proper storage. 

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