Coal reforming

This case is designed with priority given to the economic indicators in comparison with to the capital costs. An this interesting observation is obtained if the priority is given to the fuel and electricity indicators in comparison to the fixed and capital cost. In this case the highest priority on the rating list is obtained for the coal reforming options. 

As in the Case 7, the priority is given fixed and capital cost in comparison with fuel and electricity cost. The coal reforming options is having priority in comparison with other options under consideration. 

Hydrogen should not be produced using electricity generated by burning fossil fuels. Instead, natural gas or coal reformers should be used at first, and replaced by renewable energy sources as soon as possible. C02 capture from reformers should be seriously considered. 

Coal Reforming Hydrogen with CO2 sequestration Renewable Energy Hydrogen/... 

Some 30% of world production was based on coal reforming (declining rapidly) C+H O = H +CO at 1300 K and CO+H O = 1 + COj with FeO-CiOj-ThOj catalyst. 

Coal reforming - Not good because of pollution and high temperature work. 

Another nuclear heat application system that offers reduction potential is the conversion of coal by gasification to other synthetic fuels. The gasification process selected is dependent on what type of fuel is desired. Hydro-gasification is appropriate for H2 or CH4 production, whereas partial oxidation and steam gasification are better suited for methanol production. The latter process has been proposed for a nuclear coal reforming system with methane reformer and steam gasifier based on a 450 MW(th) HTGR. With an input of 93 t/h of water and 34.5 t/h of coal and 27,490 Nm /h of methane, the methanol production rate would be 101 t/h plus 68 MW(e) electricity [31]. 

Commercially, xylene is obtained by the catalytic reforming of naphthenes in the presence of hydrogen see toluene) or was formerly obtained from coal tar. The material so-produced is suitable for use as a solvent or gasoline ingredient, these uses accounting for a large part of xylene consumption. If xylene is required as a chemical, separation into the iso-... 

Synthesis gas is obtained either from methane reforming or from coal gasification (see Coal conversion processes). Telescoping the methanol carbonylation into an esterification scheme furnishes methyl acetate directly. Thermal decomposition of methyl acetate yields carbon and acetic anhydride,... 

Coal gasification technology dates to the early nineteenth century but has been largely replaced by natural gas and oil. A more hydrogen-rich synthesis gas is produced at a lower capital investment. Steam reforming of natural gas is appHed widely on an iadustrial scale (9,10) and ia particular for the production of hydrogen (qv). 

Cyclic Hydrocarbons. The cyclic hydrocarbon intermediates are derived principally from petroleum and natural gas, though small amounts are derived from coal. Most cycHc intermediates are used in the manufacture of more advanced synthetic organic chemicals and finished products such as dyes, medicinal chemicals, elastomers, pesticides, and plastics and resins. Table 6 details the production and sales of cycHc intermediates in 1991. Benzene (qv) is the largest volume aromatic compound used in the chemical industry. It is extracted from catalytic reformates in refineries, and is produced by the dealkylation of toluene (qv) (see also BTX Processing). 

Naphtha at one time was a more popular feed, and alkah-promoted catalysts were developed specifically for use with it. As of 1994 the price of naphtha in most Western countries is too high for a reformer feed, and natural gas represents the best economical feedstock. However, where natural gas is not available, propane, butane, or naphtha is preferentially selected over fuel oil or coal. 

Coal can be processed to H2 by heat from a high temperature, gas-cooled reactor at a process efficiency of 60—70%. Process steps are coal hquefaction, hydrogasification of the Hquid, and steam reforming of gaseous products (179). 

Of the raw material hydrogen sources—natural gas, coal, and petroleum fractions—natural gas is the most often employed in ammonia plants in the 1990s and steam reforming is by far the most often used process. Partial oxidation processes are utilized where steam-reformable feeds are not available or in special situations where local conditions exist to provide favorable economics. Table 5 fists the contribution of the various feedstocks to world ammonia... 

Capital costs which foUow the same trend as energy consumption, can be about 1.5 to 2.0 times for partial oxidation and coal gasification, respectively, that for natural gas reforming (41). A naphtha reforming plant would cost about 15—20% more than one based on natural gas because of the requirement for hydrotreatiag faciUties and a larger front-end needed for carbon dioxide removal. 

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