This week, a senior technical executive delegation from Iran's ZARRIN Group arrived at our production base to conduct several days of in-depth technical discussions with our combustion technology team on the feasibility of replacing natural gas with low-grade coal powder in Iranian industrial applications. The two sides focused on validating combustion solutions for locally available Iranian coal characterized by high ash, low volatile matter, and high moisture, and reached preliminary cooperation intentions for applications in zinc-lead smelting and cement kiln operations.
Tackling the Low-Grade Coal Challenge with Custom-Engineered Burners
Iran's industrial sector has long relied on natural gas as its primary energy source, but recurring gas supply constraints have made finding reliable alternative fuels an urgent priority for local smelting and building materials enterprises. However, certain Iranian coal deposits are of poor quality, with typical specifications of ash content as high as 20–25%, volatile matter of only 8–13%, and moisture of 8–12%-placing them firmly in the category of difficult-to-burn, low-grade coal. Such coal has a high ignition temperature and poor burnout characteristics, while high ash content tends to cause slagging and wear in the furnace, imposing extremely high demands on burner design.
To address this pain point, our technical team presented ZARRIN with a multi-channel swirl burner solution engineered specifically for low-grade coal. The core advantage of this design lies in its online-adjustable flame geometry: by independently controlling the swirl intensity and axial momentum of each air channel, operators can adjust flame shape and length in real time according to actual coal quality fluctuations and furnace operating conditions, ensuring stable ignition and efficient burnout even under low-volatile conditions. Meanwhile, critical burner components feature customized wear-resistant ceramic liners and anti-slagging coatings, effectively countering the erosion and deposition risks associated with high-ash coal.
CFD Simulation to Precisely Match Zinc-Lead Smelting and Cement Kiln Conditions
During the solution validation session, our company demonstrated its CFD combustion simulation capabilities for the full zinc-lead concentrate-to-ingot process as well as for cement rotary kilns. The roasting and smelting stages of zinc-lead processing are highly sensitive to temperature field uniformity and atmosphere control, while cement kilns require flames with high radiative intensity and good shape retention. Based on the coal quality data and furnace parameters provided by ZARRIN, our CFD team presented preliminary simulation results on site, visually illustrating the flame temperature distribution and species concentration fields of the customized burner under different loads-providing a quantitative basis for subsequent equipment selection and process parameter optimization.
ZARRIN expressed strong interest in the adjustability and fuel flexibility of our burners, particularly recognizing that fuel switching from natural gas to coal powder can be achieved by replacing core burner components without major modifications to the existing furnace structure. The two sides agreed that the next step will be to conduct joint CFD modeling for specific plant furnace types and to arrange for on-site trial burns of our burner prototype in Iran.
This engagement marks a substantive step forward in our high-technology combustion equipment's expansion into the Middle East heavy industry market, and lays a solid foundation of technical trust for subsequent projects involving low-grade coal-to-gas substitution retrofits in Iran.
