Whole-body two-sided flame separating type heating rotary kiln and method for producing direct reduction iron co-production carbon base fertilizer

Abstract

The invention relates to a whole-body two-sided flame separating type heating rotary kiln and a method for producing direct reduction iron co-production carbon base fertilizer. According to the invention, a rotary kiln cylinder is composed of two cylinders namely an outer cylinder and an inner cylinder; an in-depth reduction chamber is formed between the outer cylinder and the inner cylinder and is divided into 6 to 12 in-depth reduction chambers by support partition boards; each separated in-depth reduction chamber is filled with equivalent reduced material, the filling rate is increased by 6 to 12 times, and the productivity of direct reduction iron of the rotary kiln is also increased by 6 to 12 times, so that the production capacity of the kiln is greatly improved, the kiln size is relatively reduced, and the investment on the kiln is also greatly reduced relatively. Except carbon, biomass materials including straws and the like can be used as a reduction agent, so that pollution to the environment caused by combustion of the biomass materials is avoided, waste materials are recycled, high-concentration coal gas and by-products of co-production biochar base fertilizer are recycled, energy conservation, emission reduction and carbon drop are realized, and NOx is not generated.

Description

technical field [0001] The invention belongs to the field of metallurgical equipment and agricultural technology, and in particular relates to a whole-body double-sided flame-insulated heating rotary kiln and a method for co-producing carbon-based fertilizer by direct reduction of iron. Background technique [0002] Crop straw is an excellent biomass energy, and it has a large output every year. In recent years, during the summer harvest and autumn and winter, there are always a large amount of wheat, corn and other straws burned in the field, which produces a lot of thick smoke. Not only It has become the bottleneck of rural environmental protection, and even the chief culprit of the urban environment. Crop straw has become a new source of pollution in rural areas. As a large agricultural country, our country can generate more than 700 million tons of straw every year, which has become "waste" that is "not very useful" but must be disposed of. If it is completely handled b...

AI Technical Summary

Problems solved by technology

However, my country's current direct reduced iron technology is relatively lagging behind. The annual output of reduced iron is less than 600,000 tons, accounting for less than 1% of the world's total output of reduced iron.

[0020] In the existing external heating (flame separation) rotary kiln in the market, due to the supporting device of supporting ring and supporting wheel in the middle of the kiln, only the supporting ring and supporting wheel can be left in the heating furnace, and the high temperature section of the kiln is disconnected. , cannot be heated for a long distance, and the temperature curve is wavy, forming a segmented external heating (flame-type) rotary kiln heating furnace. Therefore, the scale of the kiln is small, the reduction temperature is low, and the temperature in the high-temperature zone is discontinuous and unstable , it is impossible to realize the long-distance heating of the rotary kiln, the reduction kiln is short, the production capacity is low, the temperature curve fluctuates greatly, and it cannot meet the requirements of reduced iron for the continuity and stability of the reduction temperature, and can only be used on a small scale for chemical industry, non-ferrous precious metals, etc. Industries with less processing capacity cannot satisfy the application and development in the field of reduced iron

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