CONTACT APPARATUS FOR OXIDIZING SULFUR DIOXIDE AND SYSTEMS FOR PRODUCING SULFURIC ACID

摘要

A method is disclosed for oxidizing sulfur dioxide using the contact process in which a gas stream comprising the sulfur dioxide and oxygen itself is used as the cooling medium in a contact apparatus comprising a double pipe heat exchanger. In associated systems for producing sulfuric acid, certain heat exchangers can be omitted thereby allowing for simpler and less expensive systems. The invention is suitable for systems using either a single or, in particular, a double absorption process. Further, the invention is suitable in new systems or in a retrofit of existing systems.

主权项

1. A method of oxidizing sulfur dioxide in a gas stream comprising sulfur dioxide and oxygen at a supply temperature, the method comprising:
providing a first contact apparatus comprising a double pipe heat exchanger comprising:
an inner pipe comprising a first contact catalyst mass, andan essentially concentric outer pipe; exchanging heat with the gas stream to adjust the gas stream to a first contact apparatus inlet temperature; flowing the gas stream between the inner and outer pipes of the double pipe heat exchanger; and collecting the gas stream exiting from between the inner and outer pipes and flowing the gas stream countercurrently through the inner pipe of the double pipe heat exchanger,wherein the gas stream is the cooling medium for the first contact apparatus and is heated to a catalyst activation temperature as it flows between the inner and outer pipes and is heated to a first contact apparatus outlet temperature as it flows through the inner pipe; and whereby a portion of the sulfur dioxide in the inner pipe is oxidized to sulfur trioxide.