Coke passivation treatment technology
Thread Content
Coke passivation treatment technology refers to a treatment method that can improve the thermal properties of coke during or after the coking process. The principle is to use certain mineral additives to reduce the reactivity of coke, which means to reduce the reaction ability of coke with carbon dioxide gas at high temperatures, inhibit the gasification reaction of coke in the blast furnace, thereby increasing the strength of coke after reaction, reducing the degree of damage and deterioration of coke particle size, and ultimately improving the production and operation conditions of the blast furnace. Although the mechanism and principle of passivation treatment have been discovered as early as the 1960s, it has not been applied in actual industrial production. Until recent years, laboratory research and industrial application tests have been carried out in China, and the progress has been very rapid, and it is expected to form a new coke post-processing technology. Passivation treatment technology can effectively improve the thermal quality of coke. Whether it is added in coal blending, added during coke quenching or sprayed on the surface of cold coke, it can reduce CRI by more than 3 to 5 percentage points and increase CSR by more than 3 to 8 percentage points, thus ensuring the stability of blast furnace conditions, smooth operation, increased production, coke saving, and increased coal injection volume. The processing cost per ton of iron is 4 to 6 yuan. Main method 1. Boric acid 70-90%, borax 0-10%, fineness below 500 mesh, purity above 98%, silica 5-30%. The coke passivating agent is stirred with heated water to prepare a modifier solution with a concentration of 1 to 4%. The injection amount is 1 to 5% of the weight of the coke, and is sprayed on the surface of the coke in a three-dimensional cross-mist form through a booster pump and a special nozzle. It is low cost and can improve the thermal properties of the coke, but the effect is not obvious. 2. Imported reagents have complex ingredients, are expensive, and the cost is too high, so they cannot be promoted. For improvement methods, please read the expert’s tips: handshake
Which companies have done or are doing coke passivation treatment? ? What is the specific treatment effect? How economical or popular it is. I think some steel plants may do this kind of treatment in their own coking plants. I’m afraid not many pure coking companies do this. I don’t know what the development scenario will be.
Our factory has done experiments and learned from Jigang. Adding boric acid to the coke quenching pool, the treatment cost per ton of coke is 16 yuan, the CRI is reduced by more than 3.5 percentage points, the CSR is increased by more than 4 percentage points, the blast furnace smelting efficiency is improved, and the coke ratio is reduced. However, it was not recognized by the company, so it could not be promoted.
The key is to see the application effect in the blast furnace. It must indeed reduce the coke ratio and increase the amount of coal injection. It must be recognized and accepted by iron-making. No matter how active the coking is, it will not work. There are two mechanisms for spraying boron compounds. The first is a physical effect, which seals the coke pores. The second is a chemical effect, which changes the ash composition. Can these effects still be reflected in the blast furnace? After the surface is reacted, the internal physical effects are powerless. The changes in chemical composition are weakened in the blast furnace system, and the effect is no longer so obvious. My personal opinion needs to be discussed in depth.
I particularly agree with what the 5th floor said. We Jiaohua people are so oppressed and exploited by the iron-smelting people:'( :@.