Superheated Methane

Solution Data for methane are given in Perry s Chemical Engineers Handboo From the table of properties for superheated methane,... 

Interpolation in the tables for superheated methane at 60 bar gives the temperature of the gas entering the throttle valve as 206.5 K. 

In the catalytic steam reforming of natural gas (see Fig. 2), the hydrocarbon stream, principally methane, is desulfurized and, through the use of superheated steam (qv), contacts a nickel catalyst in the primary reformer at ca 3.04 MPa (30 atm) pressure and 800°C to convert methane to H2. 

For equation 26, starting with methane and soHd sulfur at 25°C, and ending with gaseous products at 600°C, the reaction is endothermic and requires 2.95 MJ /kg (705 kcal/kg) of CS2. The reaction of methane and sulfur vapor in the diatomic form is actually exothermic (23,78). Superheating of the sulfur is claimed to be preferable (79), and series operation of reactors offers a means of reducing process temperatures at which the sulfur dissociates (80). 

The quite loud explosions (either immediate or delayed) which occur when LNG (containing usually high proportions of heavier materials) is spilled onto water are non-combustive and harmless [1]. Superheating and shock-wave phenomena are involved [2], There is a similar effect when LNG of normal composition (90% methane) is spilled on to some CsCghydrocarbons or methanol, acetone or... 

Warren Spring describes calibration with methane as a tracer gas. The same holds for cleaning the device. In France it is proposed to clean with superheated steam, followed by a test if every trace of odour is eliminated. 

Stem, L.A. Kirby, S.H. Durham, W.B. (1998). Polycrystalline Methane Hydrate Synthesis from Superheated Ice, and Low-Temperature Mechanical Properties. Energy and Fuels, 12 (2), 201 -211. 

Elemental sulfur1-4 occurs naturally in association with volcanic vents and, in Texas and Louisiana, as underground deposits. The latter are mined by injecting air and superheated water, which melts the sulfur and carries it to the surface in the return flow (the Frasch process). Most of the sulfur used in industry, however, comes as a by-product of the desulfurization of fossil fuels. For example, Albertan sour natural gas, which often contains over 30% (90%, in some cases) hydrogen sulfide (H2S), as well as hydrocarbons (mainly methane) and small amounts of C02, carbonyl sulfide (COS), and water, is sweetened by scrubbing out the H2S and then converting it to elemental S in the Claus process.5 The Claus process is applicable in any industrial operation that produces H2S (see Section 8.5) it converts this highly toxic gas to nontoxic, relatively unreactive, and easily transportable solid sulfur. 

The most effective method of SNG production with an HTGR is the stcam-carbon reforming process in which superheated steam reacts with pulverized coal to form methane-rich SNG. A system for accomplishing this process is shown in Fig. 24. In this system, an intermediate heat exchanger (1HX) has been used to isolate the nuclear heat source from the process steam, thus allowing the use of conventional equipment for... 

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. 

Description The gas feedstock is compressed (if required), desulfurized (1) and process steam is added. Process steam used is a combination of steam from the process condensate stripper and superheated medium pressure steam from the header. The mixture of natural gas and steam is preheated, prereformed (2) and sent to the tubular reformer (3). The prereformer uses waste heat from the flue-gas section of the tubular reformer for the reforming reaction, thus reducing the total load on the tubular reformer. Due to high outlet temperature, exit gas from the tubular reformer has a low concentration of methane, which is an inert in the synthesis. The synthesis gas obtainable with this technology typically contains surplus hydrogen, which will be used as fuel in the reformer furnace. If C02 is available, the synthesis gas composition can be adjusted, hereby minimizing the hydrogen surplus. Carbon dioxide can preferably be added downstream of the prereformer. 

Nickel Carbide,Ni,C solid, stable up to 380-400° decompd by dil acids or by. superheated steam to methane other products. Was prepd by interaction of Ni pdr with GO at 200-300°... 

In the preliminary design of a furnace for industrial boiler, methane at 25 C is burned completely with 20% excess air, also at 25°C The feed rate of methane is 450 kmol/h. The hot combustion gases leave the furnace at 300°C and are discharged to the atmosphere. The heat transferred from the furnace (Q) used to convert boiler feedwater at 25°C into superheated steam at 17 bar and 250 C. 

The product gas of the methanation section contains mainly CHi, Hj, HjO, and CO2. Removing H1O from this stream results in SNG as the final product, which leaves the system at high pressure. The heat released from the hydrogasifier product gas, and the heat generated in the methanation reactors, are used to generate superheated steam (40 bar and 540°C), which enters a steam turbine. A fraction of partly expanded steam is used to dry the biomass, while the remaining part of the steam is used for power generation. 

A process for the conversion of biomass into methanol by means of an HTGR has been proposed [3]. Wood, represented by the chemical formula C6Hg.6403.7, is gasified by superheated steam. Electrolytic hydrogen is added to the product gas and then converted to methanol or methane. Both heat and electricity are provided by an HTGR. The partial processes of steam gasification, water splitting and methanol / methane synthesis are summarized in the overall reaction [3] ... 

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