Cylinders liquefied carbon dioxide

Liquefied carbon dioxide is shipped in uninsulated cylinders, insulated portable tanks, insulated cargo tanks, and insulated tank cars. In high-pressure supply systems, it may be stored and used from single or manifolded uninsulated cylinders. In low-pressure systems, it is stored in insulated pressure vessels with controlled refrigeration systems and auxiliary heating when required. 

Cylinders that meet the following TC/DOT specifications are authorized for liquefied carbon dioxide service 3A1800, 3HT2000, 3AA1800, 3E1800, 3T1800, 3AX1800... 

Under present regulations, cylinders authorized for liquefied carbon dioxide service including fire extinguishers must be requalified by hydrostatic retest every 5 years, with three ex-... 

There are two kinds of liquefied carbon dioxide cylinders in commercial use the standard type and the siphon type. The standard cylinder, in an upright position, discharges gas inverted, it discharges liquid. The valve on the siphon cylinder is equipped with an eductor tube, also known as a dip tube, extending to the bottom of the cylinder. It discharges liquid when the cylinder is in the upright position. With the exception of fire extinguisher cylinders, all siphon-type cylin-... 

Large quantities of carbon dioxide may be obtained from a cylinder of the liquefied gas the gas should be dried by passing it through two Drechsel bottles containing concentrated sulphuric acid. A little air is present in the gas. 

The fluorine produced is either immediately used to prepare other final products or is first liquefied and delivered in steel cylinders where required. When fluorine is liquefied it is first led from the electrolyzer through a steel coil cooled to — 90 °C by dry ice. It then passes through a coil submerged in liquid oxygen, (— 183 °C) to separate the remaining traces of hydrogen fluoride, carbon dioxide and tetrafluoromethane. The product still contains a small... 

Nitrous oxide is contained and transported in its liquid phase in high-pressure gas cylinders or in liquid cylinders. It is transported as a liquefied compressed gas under high pressure in cylinders and at lower pressures and reduced temperatures in refrigerated cargo tanks and insulated portable tanks. Nitrous oxide is stored in a foam-insulated tank accompanied by a refrigeration unit, which is similar to the tank used for carbon dioxide. 

Carbon dioxide can be used to extinguish fires by smothering them. One form of portable fire extinguisher is a cylinder of liquid carbon dioxide—the gas can be liquefied at ordinary temperatures under pressures of about 70 atm. Some commercial carbon dioxide (mainly solid carbon dioxide) is made from the gas emitted in nearly pure state from gas wells in the western United States. Most of the carbon dioxide used commercially is a by-product of cement mills, lime-kilns, and iron blast furnaces. 

Handle in accordance with standard procedures for handling metal cylinders containing liquefied or compressed gases. Carbon dioxide is an asphyxiant and inhalation in large quantities is hazardous. It should therefore be handled in a well-ventilated environment equipped with suitable safety devices for monitoring vapor concentration. 

Surface tension at 90" 16.70 dynes/cm. Shipped as i liquefied gas in low pressure steel cylinders under its own vapor pressure of about 136 pounds per square inch. Contaminants are propane, ethane, carbon dioxide. 

Syringe pumps can provide pulseless flow and can be easily filled with liquid carbon dioxide. Syringe pumps do not have to be cooled because the carbon dioxide is liquefied by pressure, not temperature. However, because the pumps have limited volume, the syringe must be filled and repressurized when the pump cylinder is emptied. Also, when changing modifiers, the pump head must be thoroughly flushed to prevent carryover. The pump should be able to... 

Some liquefied gas mixtures present an additional problem, especially where components have widely varying vapor pressures. Mixtures such as 12% dimethylethylamine/88% carbon dioxide and 20% ethylene oxide/80% carbon dioxide would not remain homogeneous during withdrawal of gas from the container because they fractionate as they are removed from the cylinder. For these mixtures, special eductor tubes have been designed to permit liquid withdrawal and thus reduce fractionation. 

Carbon dioxide is stored in pressure-liquefied state in small containers like compressed gas cylinders and cylinder bundles. Large quantities of COj are transported in special tank trucks respectively railroad tank cars in cryogenic liquefied state, analogous to the gases described in Table 11.1. For the transport of solid CO2 (dry ice), coolers e.g. of polystyrene are used (cf Chapter 6). 

Gases in the nonflammable, liquefied compressed gas category include carbon dioxide, nitrous oxide, and others. Liquefied gases must be filled by weight, not by pressure. Note that this section does not apply to Specification TC/DOT-4L cylinders. 

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