Fire tubes hazard

The hazard tree also helps identify protection devices to include in equipment design that may minimize the possibility that a source will develop into a condition. Examples would be flame arrestors and stack arrestors on fire tubes to prevent flash back and exhaust sparks, gas detectors to sense the presence of a fuel in a confined space, and fire... 

Controls for laser operations depend on prevention of the beam from striking persons directly or by reflection. Effects will depend on the power output of the laser, but even the smallest is a potential hazard if the beam is permitted to strike the body and especially the eye. Low output lasers are normally used in the construction industry as levelling devices. Workers with lasers should know the potential for harm of the equipment they work with, and should be trained to use it and authorised to do so. If the beam cannot be totally enclosed in a firing tube, eye protection should be worn which is suitable for the class of laser being operated (classification is based on wavelength and intensity). A specific risk assessment should be made before the use of laser equipment is authorised. 

Figure 1.6 shows a typical direct fired heater. Oil flows through an inlet distributor and is heated directly by a fire box. The heat may be supplied by a heating fluid medium, steam, or an electric immersed heater. Direct heaters are quick to reach the desired temperature, are efficient (75-90%), and offer a reasonable initial cost. Direct fired heaters are typically used where fuel gas is available and high volume oil treating is required. On the other hand, they are hazardous and require special safety equipment. Scale may form on the oil side of the fire tube, which prevents the transfer of heat from the fire box to the oil emulsion. Heat collects in the steel walls under the scale, which causes the metal to soften and buckle. The metal eventually ruptures and allows oil to flow into the fire box, which results in a fire. The resultant blaze, if not extinguished, will be fed by the incoming oil stream. 

Some gas processes use direct fired furnaces. Process fluid flows inside tubes that are exposed to a direct fire. In this case radiant energy is important. Furnaces are not as common as other devices used in production facilities because of the potential fire hazard they represent. Therefore, they are not discussed in this volume. 

Where water will create a serious fire or personnel hazard, a suitable nonwater automatic extinguishing system should be considered. Penetrations through fire-rated floor, ceiling, and wall assemblies by pipes, conduits, bus ducts, cables, wires, air ducts, pneumatic tubes and ducts, and similar building service equipment should be protected in accordance with NFPA 101 , Life Safety Code. All floor openings should be sealed or curbed to prevent liquid leakage to lower floors. Door assemblies in 1 -hour rated fire barriers should be y4-hour rated. Door assemblies in 2-hour rated fire barriers should be 1 V2-hour rated. 

Castor Oil, Oxidized, Heating of castor oils in intimate contact with air or oxygen at temps of 80 to 130°, with or wo a catalyst, produce oils of high viscosity and higher d, than untreated castor oils. The oxidized oils, known also as "blown oils are used as plasticizers in lacquers, artificial leathers, oil cloths and similar products (Ref 5,p 241). It was claimed by Nakamura (AddnlRef d) that a small quantity of peroxide was formed when castor oil was treated with air at ca 155°. Mondain-Monval Marteau(Addnl Ref e) claimed that direct oxidation of castor oil (as well as of some other vegetable oils) by air in a heated glass tube also produced peroxides Refs l)Daniel(1902), 472 2)Thorpe 2(1938), 420-22 3)CondChemDict(1942), 288(Cheddites) 4)Davis( 1943), 258, 269, 358-60 365 5)Kirk Othmer 3(1949), 237-44 6)Izzo, Pirotecnia(1950), 226-7 239 7)Kirk Othmer 11(1953), 323 8) Sax(1957), 444(Toxicity fire hazard of castor oil) 9)CondChemDict(1961), 229 10)US... 

The inverted filtration method of Bost and Constable (p. 81) is particularly advantageous for filtering hot solutions of nitrobenzyl bromide, since it reduces the fire hazard and the manipulation of the lachrymatory solutions. To avoid clogging, a tube of 8-10 mm, bore must be used for connecting the filtering flasks. About 3.5 1, of ligroin may be recovered from the mother liquors. 

Financing costs, 196, 207-208, 211 Finishing in equipment fabrication, 449 Fiimed-tube heat-exchanger costs, 616 Fire and explosion hazards, 55-59 Firm process design, 14, 18 Fittings ... 

Polymerization of cis- or trans-pentadienes as inclusion compounds with deoxycholic acid, by y-irradiation, gave optically active polymers.The electrochemical determination of vitamin D in the presence of vitamin A has been explored. Substantial losses of corticosterone and its 11-deoxy-derivative occurred when methanolic solutions were evaporated in soda-lime test tubes, although borosilicate tubes were satisfactory. The fire and explosion hazards have been assessed for a variety of commercial steroids in aerosol form. A review of... 

---