Coproducing cement technological method of producing acid using phosphogypsum and sulfur

Abstract

The present invention relates to a process capable of simultaneously preparing acid and producing cement by combining phosphogypsum with sulfur. It is characterized by utilizing waste slag phosphogypsum obtained by wet process phosphoric acid production to prepare acid and produce cement. In the concrete, the invented process includes the following steps: utilizing low-concentration SO2 gas discharged out from rotary kiln of phosphogypsum acid-making system and making said kiln gas undergo the processes of washing, cleaning and drying, then be mixed with high-concentration SO2 gas discharged from sulfur acid-making system to obtain the SO2 gas whose concentration is 8-9%; and adopting an advanced two-stage two-absorption acid-making process to prepare sulfuric acid; at the same time firing the phosphogypsum in the rotary kiln to obtain cement clinker, grinding and blending so as to obtain cement.

Description

Technical field:

[0001] The present invention relates to a process method for combining phosphogypsum and sulfur to produce acid and co-produce cement. It uses wet-process phosphoric acid to produce waste residue phosphogypsum to produce cement sulfuric acid. Specifically, it refers to the use of phosphogypsum acid system to produce low-concentration SO from a rotary kiln. 2 Gas, the kiln gas is washed, purified and dried, and the high concentration SO 2 The gas is mixed to form SO with a concentration of 8-9% by volume 2 The gas is made into sulfuric acid by the advanced two-turn-two-suction acid production process, and at the same time, phosphogypsum is fired into cement clinker in a rotary kiln, and then cement is made into cement through grinding and batching. Background technique:

[0002] The main component of waste phosphogypsum produced by wet-process phosphoric acid production is CaSO 4. 2H 2 O, is currently mainly used to produce cement and produce sulfuric acid...

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