A system and method for recovering calcium carbonate and sulfur by calcining gypsum

Abstract

The present invention relates to a system and method for recovering calcium carbonate and sulfur by calcining gypsum, comprising: coal gasification-calcining U-shaped furnace, H 2 O‑CO 2 The processor, the Claus reactor, the right coal gasification section of the coal gasification-calcination U-shaped furnace are connected to the calcium-based substance storage bin and the coal powder storage bin respectively, and the left calcination section of the coal gasification-calcination U-shaped furnace is connected to the The gypsum storage bin is connected, the top of the calcination section on the left side of the coal gasification-calcination U-shaped furnace is connected to the high-temperature separator, and the bottom of the high-temperature separator is connected to the calcium sulfide-calcium oxide cooler, H 2 O‑CO 2 The processor and the calcium carbonate storage bin are connected in sequence, and the H 2 O‑CO 2 The processor is also connected to the Claus reactor, and the Claus reactor is connected to the sulfur recovery device and the sulfur storage bin in sequence, and the sulfur recovery device is also connected to the flue gas purification system. The difficult-to-handle industrial by-product gypsum is used to prepare sulfur and calcium carbonate powder, which can replace limestone as a desulfurization and denitrification agent for recycling, and can also be used as a catalyst for coal gasification process.

Description

technical field [0001] The invention belongs to the field of resource utilization of solid waste, and in particular relates to a technique and method for recovering calcium carbonate and sulfur by calcining gypsum. Background technique [0002] The information disclosed in this background section is only intended to increase the understanding of the general background of the present invention, and is not necessarily taken as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to those skilled in the art. [0003] At present, the production of industrial by-product gypsum in my country is about 118 million tons, and the comprehensive utilization rate is only 38%. Among them, desulfurization gypsum is about 43 million tons, with a comprehensive utilization rate of about 56%; phosphogypsum is about 50 million tons, with a comprehensive utilization rate of about 20%; other by-product gypsum is about 25 million tons, with a com...

AI Technical Summary

Problems solved by technology

Although the utilization rate of phosphogypsum and desulfurized gypsum in Japan is over 90% (there is a serious lack of natural gypsum resources in Japan), the amount is relatively small, and it is also in low-end low-tech fields such as building materials

[0006] On the other hand, the inventors found that our country is short of sulfur resources, and a large amount of sulfur needs to be imported from abroad every year. Sulfur is one of the indispensable chemical raw materials. A large amount of reliance on imports will not only affect the stability of the domestic sulfur market, but also be of great importance to national security. potential threat

At present, most of the flue gas sulfur resource utilization technologies in my country are used to prepare sulfuric acid. However, due to the difficulty in storage and transportation of sulfuric acid, it can only be supplied point-to-point, which greatly limits the application range of sulfur resources.

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