Compressed methane gas

Yue, Z.Q. 2013d. On nature of earthquakes with cause of compressed methane gas expansion and migration in crustal rocks, Proceedings of the 5-th Biot Conference on Poromechanics (BIOT-5), July 10-12,2013, Vienna, Austria. 

METHANE. CH4. Aluminum alloys have been used for pressure vessels in the storage and transport of compressed methane gas. Aluminum alloy tanks and pipe lines have been used extensively for handling liquid methane at temperatures as low as — 160°C (-256°F). See also Ref (1) p- 136. (3) pp. 103, 214, (7)p. 121. 

A methane gas stream taken off the demethanizer process, and still at 350 psig, is compressed via byproduct energy from the turboexpanders and raised to 410 psig. The gas is then introduced into a 15,000 hp compressor and raised to 850 psig for delivery back to the El Paso Natural Gas Company. The 60 psig boost by each turboexpander represents a 15% reduction in required horsepower. This amounts to considerable energy saved and is yet another reason why the turboexpander is useful in a cryogenic process of this type. 

An automobila that runs on nntural gas. (a) The vehicle pulled up to a CNG (compressed natural gas) pump. The gas is 90% methane, according to the label on the pump, (b) The car s gas tank (which occupies the dark space inside the back of the trunk) is being filled. 

Every gas consists of particles, whether as atoms (such as neon) or as molecules (such as methane). To a relatively good first approximation, any atom can be regarded as a small, incompressible sphere. The reason why we can compress a gas relates to the large separation between the gas particles. The first effect of compressing a gas is to decrease these interparticle distances. 

For WTW analysis, it is a sufficiently accurate assumption, that natural gas mainly consists of methane (CFI4). Compressed natural gas is also referred to as CNG . Natural gas is extracted, processed, transported and distributed via pipeline to the filling stations, where it is compressed to about 25 MPa. Natural gas sources may vary for different countries. Depending on the source (natural gas quality) and the transport distance (e.g., 4000 km or even 7000 km from Russia, depending on the relevant gas fields) the auxiliary energy needs or energy losses, and hence the GHG-relevant emissions can vary. For the calculation of the energy requirement and GHG emissions for the supply of natural gas, a transport distance of 4000 km is assumed. 

A relevant example is the use of lifetimes to characterize the reactivity of organics. Compressed natural gas (CNG), for example, is a widely used fuel whose major component is methane, CH4. The only known significant chemical loss process for CH4 is reaction with OH ... 

Najour, G. C. King, A. D. Solubility of Naphthalene in Compressed Methane, Ethylene, and Carbon Dioxide. Evidence for a Gas-Phase Complex Between Naphthalene and Carbon Dioxide. J. Chem. Phys. 1966, 45, 1915-1921. 

Methane gas can be condensed by cooling and increasing the pressure. A 600 L sample of methane gas at 25°C and 100 kPa is cooled to -20°C. In a second step, the gas is compressed until the pressure is quadrupled. What will the final volume be (Hint Use both Boyle s law and Charles law to answer this question.)... 

In an ammonia plant (Figure 4.2), the synthesis gas from the reformer furnace is fed into a secondary reformer vessel, where air is added through a burner to create outlet vessel temperatures of -1,800° F (980° C). The outlet of the secondary reformer vessel is cooled in a quench steam generator and sent to a shift converter this is followed by a carbon dioxide removal system such as the one in a hydrogen plant. The purified nitrogen from the air added in the secondary reformer vessel and hydrogen synthesis gas is fed to a methanator to convert residual oxides of carbon back to methane (which is inert in the ammonia conversion) the gas is then compressed to -3,000 psia (2,070 kPa). The compressed synthesis gas is fed to an ammonia converter vessel. As the synthesis gas passes over catalyst beds, ammonia is formed. The ammonia product is then cooled and refrigerated to separate out impurities. 

It is economic to cool the compressed methane for liquefaction by the gas that does not liquefy in the throttling process. In the Claude process, the gas at an intermediate temperature splits into two parts. One of them enters the expander and exhausts as a saturated or slightly superheated vapor, and produces work. The remaining gas is further cooled in the second heat exchanger and throttled to liquefy. The portion that is not liquefied is combined with the output vapor of the expander and recycled into the compressor. 

The addition of a small amount of methane to the mixture tends to increase the work per unit mole required to compress the gas. 

There is interest in compressed natural gas (CNG), which is largely methane, as a clean fuel for passenger and heavy-duty vehicles. However, relative cost and ease of distribution and availability are additional factors to be considered in order for its use to become widespread. In contrast to U.S. legislation, in Europe methane is not excluded from the hydrocarbon emission measurement, and so it would appear that the European requirements... 

A cylinder, of capacity 100.0 liters, contains methane gas originally at 200 atm. and 25 C. Determine by means of the compressibility chart the weight of gas used up when the pressure in the cylinder has fallen to 50.0 atm. Compare the result with that for (i) an ideal gas, (ii) a van der Waals gas. 

Natural gas is a fossil fuel that is found in underground reservoirs. It consists chiefly of methane, with smaller amounts of other hydrocarbons such as ethane, propane, and butane along with inert gases such as carbon dioxide, nitrogen, and helium. The actual composition varies, depending on the region of the source. As an engine fuel, natural gas may be used either in a compressed form, compressed natural gas (CNG) or in a liquid form, liquefied natural gas (LNG). 

The density of methane is approximately 1/1000 of that of petroleum. Hence, to store enough gas to have a calorific value that is equal to that of 1,000 tons of petroleum a storage capacity of 1 million cubic feet is required. Since it is very difficult to find suitable materials of construction to store the highly compressed natural gas (to reduce the volume), alternative sources of... 

Alternative fuels should be substantially non-petroleum in order to provide energy security and environmental benefits, and to substitute for conventional fuels such as gasoline and diesel. Natural gas consisting mainly of methane fits this definition, and the natural gas is mainly stored as compressed natural gas in pressure vessels or as adsorbed gas that can be stored in a porous solid at a low pressure. An important advantage of zeolites over activated... 

TITc) 2.0, is very high compared to that of carbon dioxide, rR l.l. To overcome ideal gas behavior, it is necessary to compress methane to very high pressures to obtain reasonable methane densities and, hence, solvent power. 

Najour, G. C., and A. D. King, Jr. 1966. Solubility of naphthalene in compressed methane, ethylene, and carbon dioxide Evidence for a gas-phase complex between naphthalene and carbon dioxide. J. Chem. Phys. 45 1915. 

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