Compressed gases transportation

For distributing larger quantities of gaseous helium, argon, and occasionally neon, a number of large, horizontal, compressed gas cylinders are manifolded on tmck semitrailers (called tube trailers) or railroad cars. Like individual cylinders, these serve both as transport containers and rental storage containers. Capacities of tube trailers range from about 300 to 5,000 m (10,000—175,000 fT) of gas. 

Butadiene is primarily shipped in pressurized containers via railroads or tankers. U.S. shipments of butadiene, which is classified as a flammable compressed gas, are regulated by the Department of Transportation (254). Most other countries have adopted their own regulations (30). Other information on the handling of butadiene is also available (255). As a result of the extensive emphasis on proper and timely responses to chemical spills, a comprehensive handbook from the National Fire Protection Association is available (256). 

The second Hquefaction process is carried out at temperatures from 261 to 296 K, with Hquefaction pressures of about 1600—2400 kPa (16—24 atm). The compressed gas is precooled to 277 to 300 K, water and entrained oil are separated, and the gas is then dehydrated ia an activated alumina, bauxite, or siHca gel drier, and flows to a refrigerant-cooled condenser (see Drying agents). The Hquid is then distilled ia a stripper column to remove noncombustible impurities. Liquid carbon dioxide is stored and transported at ambient temperature ia cylinders containing up to 22.7 kg. Larger quantities are stored ia refrigerated iasulated tanks maintained at 255 K and 2070 kPa (20 atm), and transported ia iasulated tank tmcks and tank rail cars. 

The compressors to be covered in this book are those using mechanical motion to effect the compression. These types of compressors are commonly used in the process and gas transport/distribution industries. A partial list of these industries includes chemical, petrochemical, refinery, pulp and paper, and utilities. A few typical applications are air separation, vapor extraction, refrigeration, steam recompression, process and plant air. 

Adiabatic compression test High pressure is applied rapidly to a liquid in a U-shaped metal tube. Bubbles of hot compressed gas are driven into the liquid and may cause explosive decomposition of the liquid. This test is intended to simulate water hammer and sloshing effects in transportation, such as humping of railway tank cars. It is very severe and gives worst-case results. 

Hydrogen can be stored and transported as a compressed gas, a cryogenic liquid or in solids. Liquid hydrogen is closer to gasoline in the areas of volume and vehicular weight. In commercial aircraft, the takeoff... 

After the hydrogen is extracted, it must be compressed and transported, if this equipment operates on fossil fuels, they will produce C02. Running an engine with hydrogen extracted from natural gas or water could produce a net increase of C02 in the atmosphere. 

Seamless steel pressure vessels are the most common method in use today for hydrogen transportation at short distances (<200 km) and when small quantities are involved (up to about 500 kg). The different vessel options include cylinders, manifolded cylinder pallets and tube trailers. While single cylinders or manifolded pallets are trucked to the destination and off loaded, tube trailers, which consist of several steel cylinders mounted to a protective framework, are often left in place and replaced when empty. Transporting hydrogen in liquefied form is seven times more efficient in terms of actual hydrogen weight transported than using compressed gas cylinders. 

In short pipelines are the preferred option for large quantities and long distances liquid hydrogen is for smaller volumes and transport over long distances, and compressed gas is for small quantities over short distances. 

The sources of acetylene, nitrous oxide, and sometimes air are usually steel cylinders of the compressed gases purchased from specialty gas or welders gas suppliers. Thus, several compressed gas cylinders are usually found next to atomic absorption instrumentation and the analyst becomes involved in replacing empty cylinders with full ones periodically. Safety issues relating to storage, transportation, and use of these cylinders will be addressed in Section 9.3.7. The acetylene required for atomic absorption is a purer grade of acetylene than that which welders use. 

All precautions relating to compressed gas cylinders must be enforced—the cylinders must be secured to an immovable object, such as a wall they must have approved pressure regulators in place they must be transported on approved carts etc. Tubing and connectors must be free of gas leaks. There must be an independently vented fume hood in place over the flame to take care of toxic combustion products. Volatile flammable organic solvents and their vapors, such as ether and acetone, must not be present in the lab when the flame is lit. 

In the stripper/condenser, the gas is cooled by counterflowing condensate from the condenser. The temperature of the SO2 rich gas that leaves the condenser is used to control the amount of cooling medium that must be sent to the condenser. Condensate from the stripper is returned to the buffer mix tank. The SO2 rich gas, containing at least 90% SO2 with the remainder being water, is ready for transport to a process unit. In the refinery, this normally will be the SRU or acid plant, where it will be converted to elemental sulfur or sulfuric acid. The SO2 can also be compressed and transported if necessary. Eigure 16.9 shows a typical Belco LABSORB System. 

Traditionally, hydrogen has heen stored, transported and used in the form of compressed gas or cryogenic liquid. Recharge-ahle metal hydrides have heen proposed as an alternative solid state storage method. A dynamic research community has assembled to explore the scientific basis and evaluate the technology of this hydrogen-metal reaction Metal hydride topics have... 

Compressed Gas (Liquefied) Under U.S. Department of Transportation regulations (refer to 49 CFR 173.300), a liquefied compressed gas is defined as a gas which, under the charged pressure, is partially liquid at a temperature of 70 °F. 

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