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Natural Gas Purchasing
Published in Stephen A. Roosa, Steve Doty, Wayne C. Turner, Energy Management Handbook, 2020
Stephen A. Roosa, Carol Freedenthal
The synthetic gases that were produced had many unfavorable attributes. Water gas contained high amounts of hydrogen and carbon monoxide (CO). The CO is poisonous and people can die when exposed. The hydrogen in the water gas made it explosive, and many buildings were destroyed when gas from leaks or pipe ruptures ignited. When natural gas became available it quickly replaced synthetic manufactured gas.
The Water-gas Shift Reaction
Published in Martyn V. Twigg, Catalyst Handbook, 2018
Water-gas is an equimolar mixture of hydrogen and carbon monoxide. It is formed when steam is passed through incandescent coke, and the original process for its manufacture was developed by the town-gas industry during the latter part of the nineteenth century to supplement coal gas. The calorific value of water-gas is less than that of coal-gas and had to be raised by addition of oil, which could range from light distillate to heavy fuel oil, to give “carburetted” water-gas before the two gases could be mixed. This led to an improvement in the efficiency of gas making, and also provided a convenient means of meeting the temporary and sudden demands for gas that occurred at peak periods.136 At temperatures above 1000°C steam reacted with coke according to equation (1) but at lower temperatures carbon dioxide, which was produced according to equation (2), became increasingly important. Both reactions are endothermic, and consequently the temperature of the incandescent coke fell as the reaction proceeded.
Coal-Gas
Published in Robert Routledge, Discoveries and Inventions of the Ninteenth Century, 2018
In the process of heating, a proper regulation of the temperature is of the highest importance. It is found that when the retorts are heated to bright cherry-red, the best results are obtained. At a lower temperature a larger quantity of condensable vapours are given off, which collect in the gasholders and distributing pipes as solid or liquid, and occasion much inconvenience, while the quantity of gas obtained is decreased. On the other hand, if the temperature be too high, some of the gases are decomposed, and the quantity of carbon contained in the product is so much diminished as seriously to impair the illuminating power. Again, every second the gases after their production remain in the red-hot retort diminishes their light-giving value; for those hydro-carbons on which the luminiferous power of the gas depends, are then liable to partial decomposition; a portion of their carbon is deposited on the walls of the retort in a dense layer, gradually choking it up, while the liberated hydrogen does not add to the illuminating but to the heating constituents of the gas. A plan has been patented by Mr. White, of Manchester, for rapidly removing the illuminating gases from the retort by sweeping them out by means of a current of what has been termed “water gas.” This water gas is produced by causing steam to pass over heated coke, and is a mixture of carbonic acid, carbonic oxide, and hydrogen. Though only two of these are combustible gases—and even they do not yield light by their combustion, and, by adding to the bulk of the gas, serve rather to dilute it—yet it has been found that in some cases twice the amount of light is obtainable by White’s process than the same weight of coal supplies when treated in the ordinary manner.
Hydrogen and syngas production by catalytic gasification of algal biomass (Cladophora glomerata L.) using alkali and alkaline-earth metals compounds
Published in Environmental Technology, 2019
Abdol Ghaffar Ebadi, Hikmat Hisoriev, Mohammad Zarnegar, Hamed Ahmadi
There is a continuous increase in hydrogen yield with increasing the S/B up to 0.8 (wt/wt), while after that, the increase levels off probably due to the lower reaction rate of steam reforming reaction for further increase of S/B, as shown in Figure 3. The usage of higher amount of steam and promotes the water gas shift reaction, which consumes carbon monoxide and generates hydrogen and carbon dioxide. The reported trends for hydrogen yield with the S/B are in agreement with those obtained by Rapagna et al. [18] in steam gasification experiments. For comparison, the most significant difference between the hydrogen yields obtained from steam gasification without catalysts and in presence of NaOH at S/B of 0.8 which may be related to the higher water content in the system and the resulting sufficient amount of the thermal energy required for hydrogen production. In all cases, the tar content was decreased with increasing the S/B from 0.5 to 0.8 (wt/wt) and then continuously increased for further increase of S/B. In the best case (NaOH), the results show that the tar was reduced by from 2.3 to 1.7 (g/Nm3) when S/B changing from 0.5 to 8.0 (wt/wt). When the AAEM catalysts were used there was a noticeable reduction in the tar content in the gas, especially in the case of NaOH.
Steam gasification of oil sludge with calcined olivine
Published in Petroleum Science and Technology, 2019
A.H. Motlagh, S.V. Klyuev, A. Suendar, A.Z. Ibatova, A. Maseleno
Figure 4 shows the effect of (S/O) steam-to-oil ratio on gas composition. Adding steam to gasifier is usually done when the purpose of gasification process if hydrogen production. As it is clear, increased S/O leads to increased H2 and CO2, and decreased CO and CH4. These trends can be justified according to Le Chatelier's principle. By adding steam to gasifier, water-gas shift reaction moves towards H2 and CO2 products to balance concentration of added steam and bring the reaction to an equilibrium state.