Review and audit of a DRI plant using SL / RN technology
At the invitation of the customer, the specialists of SPA RAKURS LLC together with Ukrasa Energy LLC and Nikoprogresstroy LLC performed a review and audit of the DRI production plant using SL/RN technology on December 6-7, 2019. The factory is located in Iran.
The structure of the plant includes:
- Complex for the production of DRI;
- Smelting complex.
The DRI production complex includes:
1. Warehouse of raw iron ore;
2. Warehouse of coal;
3. The site of crushing and sorting of iron ore;
4. The site of crushing and sorting of coal;
5. The site of charge preparation;
6. Firing area (tube furnace);
7. DRI sorting section;
8. Magnetic separation section;
9. Shipment of finished products.
During the familiarization work and communication with the technical staff of the factory, our specialists determined the following:
- The DRI production complex operates on raw materials that are significantly different (for the worse) in terms of characteristics from the design;
- Oxidized iron ore is used with a content of Fetotal=56-59% with a gross rock basicity of 0.7-0.9 (up to 0.5 permissible), which leads to high crust formation in the furnace;
- The furnace loading with iron ore raw materials is 50% of the design (13 t/h), which leads to a significant increase in costs to maintain the required temperature regime of the furnace;
- The furnace burner operates on ground coal;
- Specific heat consumption through the shell of the tube furnace and with flue gases increased in comparison with the design 1.5-2 times;
- The presence of small things of -5 + 0 mm in the finished product reduces the specific productivity of the tube furnace for a suitable product;
- The use of hematite ore with an iron content of less than 55.0% as an iron ore raw material is not economically feasible due to the high slag yield at the metallurgical conversion in an induction furnace;