The production of 96% sulphuric acid on a chamber plant

Abstract

AbstractIn this paper an account is given of a tower on a chamber acid plant which has been designed and operated in order to produce 96% sulphuric acid. So far as the authors are aware, no such tower has been reported in the literature and it may well be that the one now‐described is unique. In any event the design and operation of such a tower demonstrates a method of employing this section of a chamber plant in order to obtain a very high efficiency of heat utilization and to give a grade of sulphuric acid which it has hitherto been considered only possible to supply from contact plants or by independent concentration units. It was felt that some details of this work would be of particular interest to those associated with industrial and engineering chemistry, and it is especially appropriate that the first general publication of this information should be to the Society Of Chemical Industry in Glasgow, since the tower to be described was built and operated at St. Rollox Works, Glasgow.It may be recalled at this stage, that the early plants for the production of sulphuric acid from sulphur dioxide, oxygen and water in the presence of nitrous gases consisted simply of chambers into which trays of burning sulphur and saltpetre were pushed. The first great improvement was the introduction of the Gay Lussac tower to absorb the nitrous gases in sulphuric acid, but the nitrous gases were recovered from the sulphuric acid and the acid was concentrated in a system independent of the chamber plant, until Glover introduced a tower at the front of the chambers to recover the “nitre” from the Gay Lussac tower acid and to concentrate a mixture of the “nitrous vitriol” so obtained and the acid from the chambers. It always seems, however, to have been generally considered undesirable, and certainly very difficult, to concentrate the acid to much more than 150° Tw. (82%) in the Glover tower, although it was recognized that additional heat was available by the attempts which were made to operate concentrating pans on top of the pyrites and brimstone burners.