Modern Gasworks Practice

CHAPTER XX WATER GAS : MANUFACTURE, ENRICHMENT AND USE Water gas is the term applied to the impure mixture of hydrogen and oxides of carbon which is formed when steam is passed through incandescent carbon. The basis of the process was probably discovered by Fontana in 1780, and was quickly followed up by Cavendish, Lavosier, Meusnier and otters. The first attempt to utilize water gas on a commercial scale was made in 1824 by Ibbotson, who experi-mented with a process of steaming the coke remaining in horizontal retorts at the end of the period of carbonization. Many of the earlier attempts, however, met with. failure, but a great advance was made by Gillard at Narbonne in 1856, when that town was lighted by means of blue water gas in conjunction with. platimim wire manties. In America Dr. J. M. Sanders erected a plant in 1858 which consisted of L-shaped cast-iron retorts placed in an ordinary coaJ-gas setting. The retorts were filled with charcoal and were externally heated, superheated steam together with melted rosin being admitted to the top of the retorts. Published results show that the gas was not stable, while the excessive deterioration of the retorts precluded the general adoption of the process. The intermittent system as commonly operated to-day did not make its appear-ance until 1873 whentwo processes, based on alternate periods of “ run ” and “ blow,” were introduced in the United States. One of these—the Strong process—employed a high generator made from firebrick and two secondary chambers packed with firebrick. These latter chambers, heated up during the blow, were employed as superheaters for the steam. Strong aimed purely at making a heating gas; and his system, tliough neglected in this country, was energetically followed up in Ger-many. Lowe, on the other hånd, set out to make an illuminating gas. His plant was designeel on lines very similar to those employed in present-day apparatus. That is to say, he employed for his generator a brick-lined cylindrical shell made from wTouglit iron, the fuel Testing on grate bars above a closed ash-pit. Steam and air were introduced alternately, the blue gas passing on to a large superheater packed with firebricks. Anthracite was the fuel commonly used, while the enrich-ing oil was sprayed on to the top of the fuel, the gas mixture being fixed by passage through the superheater. The Lowe system was introduced into this country in 1889. Water gas must be looked upon as essentially an auxiliary to coal gas, and in this capacity it is employed by a large number of gas undertakings as a means of providing for inerease of business and fluctuations in demand. At the outset it 689 Y Y