METHOD OF PRODUCING SULPHURIC ACID AND APPARATUS THEREFOR Russian patent published in 2014 - IPC C01B17/775 C01B17/80 

FIELD: chemistry.

SUBSTANCE: invention relates to chemical industry. Hydrogen sulphide gas is burnt in a furnace (1). The obtained process gas containing sulphur dioxide and water is fed into an exhaust-heat boiler (2) with a built-in drum separator (3) and then into a steam superheater (4). The first step of catalytic conversion includes feeding cooled gas onto a first catalyst bed of a contact apparatus (5). Sulphur dioxide is converted to trioxide on the first catalyst bed. The process gas is then fed into a gas heat exchanger (6). The cooled process gas enters a second catalyst bed, after which the gas is cooled once more and fed onto a third catalyst bed. The first conversion step is followed by absorption with circulating sulphuric acid until achieving moisture content of not more than 0.005% in the gas entering the second conversion step. Further, the process gas is fed into a heat exchanger (9). The heated gas is fed into the gas heat exchanger (6), after which the gas is fed into the second conversion step - oxidation of residual sulphur dioxide to sulphur trioxide. After the second conversion step, the process gas is cooled in the heat exchanger (9) and fed into an absorber (10).

EFFECT: invention enables to obtain acid of any concentration, simplifies the process system and improves the reliability thereof.

3 cl, 1 dwg