Gases, storage

Gas phase applications of activated carbon fall into the main categories of separation, gas storage, and catalysis. These applications account for about 20% of the total use of activated carbon, with the majority using either granular or pellet type. Table 3 shows the major gas phase applications, again along with 1987 consumption levels. 

Enhancement of gas storage capacity through adsorption occins when the overall storage density is increased above that of the normal gas density at a given pressure. The adsorbed phase has a greater density than the gas phase in equilibrium with it. However, enhancement in a storage system of fixed volume can only happen if a greater amount of gas is adsorbed compared to the volume of gas displaced by the adsorbent volume. 

All commercial carbons have been made for uses other than natural gas storage. They are for the most part granular materials and pack into vessels with a substantial inter-particle void volume which results in low bulk densities. Some... 

Komodromos, C., Frickcr, N. Slater, G., "Development of Novel Tanks for Low-Pressure Adsorbed Natural Gas Storage in Vehicles", International Association for Natural Gas Vehicles, Toronto, 1994... 

Liquefied petroleum gas Storage of LPC at Eixed Installations (HSE, HSG 34) Storage and Use of LPC at Metered Estates (HSE, CSll) Storage and Use of LPC on Construction Sites (HSE, CS6) Keeping of LPC in Cylinders and Similar Containers (HSE, CS4)... 

Benzene zero 0.005 Anemia decrease in blood platelets increased risk of cancer Discharge from factories leaching from gas storage tanks and landfills... 

Figure 3.5 shows a liquefied gas storage facility which incorporates many of these principles. CCPS (1993a) provides several other exam-... 

Gas storage cabinets were originally developed for the semiconductor industry in the 1970s. These early storage cabinets consisted of a box that enclosed the tank and connections they were operated under negative pressure and exhausted to the outside. Gas storage cabinets have become more sophisticated, adding gas detection, fire sprinklers, alarms, and pneumatic controls. " Some cabinets have point-of-operation air cleaners such as scrubbers. 

Many building and health and safety codes require the use of gas storage cabinets, exhausted enclosures, and/or separately ventilated gas storage rooms for toxic gases. These controls are also recommended for flammable and corrosive gases. 

Gas storage cabinets consist of a box that encloses the tank(s) and all connections. Many include change out capabilities and an access door. The cabinets are exhausted to remove any contaminant that may leak into the cabinet and to maintain the cabinet under negative pressure relative to the... 

Gas storage cabinets are used to contain compressed gas cylinders containing toxic, flammable, or corrosive gases. 

Gas storage cabinets are designed to contain one to four gas cylinders. The cylinders are connected to a gas distribution system which is also contained in the cabinet. Very sophisticated systems are available from cabinet manufacturers. These may include automatic or semiautomatic change-over capabilities, fire sprinklers, purging systems, and gas detection systems which may include alarms and automatic shutoff. Point-of-use scrubbers may also be incorporated into the design, depending on the gas being used (see Fig. 10.43). 

Gas storage cabinet use may be required by local, state, or national codes. These codes vary by location and the designer or user of the cabinet is referred to these codes for further information. One source of building code information in the U.S. is the Uniform Building Code and the Uniform Fire Code. ... 

FIGURE 0.43 Typical designs for gas storage cabinets (Matheson Gas Products, used with permission)... 

Burgess et al." describe a study of gas storage cabinets. In the study, coefficient of entry (CJ for various inlet/outlet configurations was measured. A tracer gas study is also described. The tracer gas study involved releasing sulfur hexafluoride (SF ) at 0.032 L s" at a critical leak position in the cabinet and measuring SFg concentration in the exhaust stream. The tracer gas was turned off when a steady exhaust stream concentration was observed and the time for the concentration to decay to 5% of steady state was measured. 

The study found that the slot-type inlet at the bottom of the cabinet door resulted in higher pressure losses (lower CJ than the diffuser or perforated plate inlet. The exhaust configuration had little effect on Q or tracer gas clearance time. The study also concluded that an exhaust rate 0.118 m s for a two-cylinder cabinet was sufficient as little improvement was seen with an increase to 0.165 m s F" The slotted inlet took longer to clear a leak than either the perforated plate or diffuser inlet. Measured coefficients of entry for a two-cylinder gas storage cabinet are shown in Table 10.9. 

Baker, W. E., J. J. Kulesz, R. E. Richer, R. L. Bessey, P. S. Westine, V. B. Parr, and G. A. Oldham. 1975 and 1977. Workbook for Predicting Pressure Wave and Fragment Effects of Exploding Propellant Tanks and Gas Storage Vessels. NASA CR-134906. Washington NASA Scientific and Technical Information Office. 

Recent uses for natural gas storage include utilizing storage to provide transportation balancing seiw-ices, to take advantage of variations in prices, to maintain wellhead production and to meet new sales commitments by marketers. 

Recommendations for the design and construction of refrigerated liquefied gas storage tanks... 

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