Application of Cold Solid Briquetting Technology
"Cold-solidified briquettes" made by high-pressure briquetting machine using sludge, dust removal ash, and iron scale produced by steelmaking as raw materials, adding lime, and using organic glue as a binder.
Cold-solid briquettes used in converter steelmaking as coolant and slagging agents can not only reduce the environmental pollution caused by dust removal, but also optimize the raw material structure of steel mills, save energy and reduce the production cost of converter steelmaking, and at the same time realize the recycling of iron-containing resources. This project conforms to the industrial policy of developing circular economy, is a new project to promote steel mills to reduce costs and gain and improve the environment, and also conforms to the company's business policy of vigorously supporting the development of non-steel industries. The economic and social benefits of this project are remarkable, and it has a good development prospect.
Some iron scale or iron concentrate can be added to dust removal ash and taphole ash in steelmaking, and then pressed into briquettes by cold-solid pelletizing process and returned to the converter as steelmaking coolant or slagging agent.
The characteristics of cold-solid briquettes:
1. Accelerate slag formation. The addition of cold-solid pellets increases the FeO content in the early stage slag, accelerates and improves the formation speed of the early stage slag and the physicochemical properties of the middle stage slag, and improves the removal of P and S in the smelting process.
2. The cooling effect is better, and the slag structure is improved. Because cold-solid pellets are added into slag in batches, the melting heat absorption can reduce the input of other slag materials accordingly. After the cold-solid pellets are added to the converter, the lime consumption can be reduced by increasing the lime melting rate and adding part of CaO into the cold-solid pellets.
3. Simplify the operation in front of the furnace. Because of the good slag removal and slag melting effect of cold-solid pellets, fluorite can be reduced or even not added instead of iron sheet, ore, and fluorite, which greatly simplifies the operation before the furnace.
4. Adding cold-solid pellets can increase the basicity of slag, decrease the solubility of MgO in slag, reduce the erosion of furnace lining and prolong the life of the converter at the initial stage of steelmaking.
5. Improve the metal yield. The content of TFe in cold-solidified pellets is 50%-55% so that the metal in converter dust can be recovered favorably.
6. Environmental pollution is reduced. The cold-solid pelletizing production line can effectively treat the dust from dry dedusting in converter steelmaking.
