Patent GB-231921-A (GB)
Title: Improvements in or relating to the manufacture of sulphuric acid
IPC: C01B17/82
Filed: 1923-12-11
Abstract: 231,921. Jackson, W. J. Mellersh-, (Hurt Engineering Corporation, G. F.). Dec. 11, 1923. Sulphuric acid.-In the manufacture of sulphuric acid by the nitration process, the interaction between the liquids and the gases is obtained by projecting the liquids into the progressing gases in successive fountains of drops which are of such size that they are not carried away by the gas stream. The plant, Fig. 3, com. prises a series of sectional flues A - - G through which the liquids flow by gravity in one direction while the gases pass over them in the opposite direction. The final concentration of the acid takes place in section A by means of the hot sulphurous gases from the burners. The conversion of nitro-sulphonic acid to sulphuric acid takes place in the sections B, C which are formed in one part divided by a transverse dam, the necessary gases flowing from section A, and the lower nitrous oxides being reoxidized in section c. Sulphur dioxide is absorbed in section D and nitrosulphonic acid vapour is formed and dissolved in the liquid, water being supplied by a pipe d. Further treatment of residual sulphur dioxide and recovery of the nitric oxides take place in sections E, F and G which supersede the usual lead chambers and Gay Lussac tower, the gases being cooled while passing from F to G by a cooler F<x>. The concentrated sulphuric acid is withdrawn into a series of cooling vessels L, M, N and finally to a storage tank O, the more dilute acid being similarly treated in tanks N<2>, O<2>. Acid required in the process is delivered by a pump P to measuring and delivery tanks Q, R from which it flows to the section G and the acid containing the recovered nitrogen oxides is stored in a tank T from which it is supplied as required by a pump U to measuring and supply tank V, Y where it is mixed with nitric acid from a tank W. The sections A - - G comprise flues of square cross-section with arched tops the walls being formed of chemical brick lined inside with lead and outside with layers of asbestos and cement covered with sand. The sections are connected by flues of slightly smaller diameter to preserve continuity of flow of the gases. The liquids which form pools at the bottom of the series of connected flues are fountained into the gases by submerged air jets issuing from nozzles formed on the ends of pipes 51 adjustable in height by nuts 55 and pivoted to removable iron plates 59 which cover recesses 58 in the side walls. The nozzles may have tapered, flared, or elongated orifices forming a fan-shaped fountain. The flues forming the sections D - - G are double the width of the preceding sections and the flue bottom 87 Fig. 11, is extended to form an external basin 89 divided from the internal portion 88 by a wall 90 provided with submerged openings 91. In these sections the liquids are caused to follow a zig-zag path between the basin 89 and the flue 88 by means of transverse walls 105, the liquid being cooled in the outer pools by coils 130. The flow of gases through the apparatus is controlled by a series of dampers. Reference has been directed by the Comptroller to Specifications 15459/12, 19084/13, 149,648, 180,546, and 187,016.