FREMGANGSMAATE FOR GJENVINNING AV SVOVELSYRE.

摘要

In a sulphuric acid recovery process, wherein the majority of acid is reclaimed and recycled by spray drying a waste acid stream, an improved process for recovering the sulphur content of the metal sulphates. The improved process comprises roasting the metal sulphates to generate metal oxides and a gaseous stream of sulphur dioxide and sulphur trioxide, which gaseous stream is fed to the spray drier to reduce the level of heated make-up air required for spray drying, and for recovery of the sulphur value contained in the gaseous stream. The process reduces the loss of sulphur value and produces a solid metal oxide powder which is easier to dispose.