High-efficiency and energy saving pulverized coal preparation solution! LM Vertical Roller Mill provides powerful support for the 800 tpd Maerz lime kiln project

Pulverized coal preparation is a critical pre process link for quality improvement and carbon reduction in lime production. Keeping pace with the green and intelligent transformation trend of the lime industry, Liming Heavy Industry’s LM vertical coal mill has been operating stably in fuel preparation projects for lime kilns across multiple regions. Relying on full chain technical capabilities, Liming Heavy Industry can customize efficient, safe and energy saving pulverized coal preparation solutions for customers according to on site conditions and production requirements of the project.

What Are the Pulverized Coal Requirements for Maerz Kilns?

Active lime is a core raw material for iron and steel metallurgy, environmental desulfurization, chemical synthesis and other industries. The finished product quality depends on the calcination process performance of the kiln. With the process advantages of parallel flow regenerative combustion, low heat consumption and low emissions, the Maerz double chamber kiln has become the mainstream core equipment for high activity calcium oxide production. Its calcination stability and product quality heavily rely on well matched pulverized coal fuel, and the technical level of the pulverized coal preparation process directly determines the kiln’s thermal efficiency, energy consumption indicators and environmental protection performance.

The Maerz kiln adopts a double chamber vertical structure with alternating operation of the calcination zone and cooling zone. It imposes extremely strict requirements on pulverized coal fuel: 200 mesh fineness, uniform particle size distribution, stable calorific value, proper volatile matter content and low moisture, to ensure complete combustion, stable flame and even calcination temperature inside the kiln. Therefore, the upstream pulverizing system must feature highprecision classification, powerful drying capacity and stable continuous operation performance.

Targeting the harsh working conditions of pulverized coal preparation for Maerz lime kilns, Liming Heavy Industry has developed the large sized, high efficiency and energy saving LM vertical coal mill. It adopts a one step preparation system that integrates drying and pulverizing in one process, delivering both low energy consumption and high production capacity. Equipped with a five level safety explosionproof measure, the mill builds a fireand explosion protection system covering the whole area, full process and all hazard sources, ensuring safe and stable system operation and providing reliable equipment support for large scale pulverized coal production specially for kilns.

Pulverizing Process Flow of LM Vertical Coal Mill

Raw coal is screened by a grid screen at the coal yard and then conveyed to a steep angle belt conveyor or elevator. After iron removal by an electromagnetic iron remover, the belt conveyor or elevator transports the raw coal into the raw coal bunker for storage. After the pulverizing system is fully started, the rod valve at the bottom of the raw coal bunker is opened and the sealed metering belt feeder is activated, feeding raw coal into the vertical coal mill for drying and grinding.

Hot air or waste gas from the hot blast furnace is drawn by the system fan into the vertical coal mill, where it conducts sufficient heat exchange with the ground raw coal inside the mill. The air stream carries pulverized coal to the separator for classification. Coarse coal particles failing to meet the fineness requirement fall back onto the grinding table for re-grinding, while qualified pulverized coal is carried by airflow into the explosion proof pulse baghouse for collection, and then discharged into the pulverized‑coal silo via a star wheel discharger.

100,000 TPA Fuel Pulverizing Project for Lime Kiln

This project supports the customer’s PhaseI 250,000 ton per year high activity calcium oxide production line. In response to the strict process requirements of the 800 tpd Maerz doublechamber kiln on pulverized coal fineness, discharging stability and continuous feeding capacity, Liming Heavy Industry provides the customer with an integrated completeset pulverized coal preparation system solution. The system can stably produce high quality 200 mesh pulverized coal, supply high efficiency fuel for kiln calcination, and ensure efficient operation and steady capacity growth of the whole production line.

Material to be processed: Coal

Finished fineness: 200 mesh

End use: Pulverized coal preparation for double chamber lime kiln

Equipment: Liming Heavy Industry LM Vertical Coal Mill

Centered on the core design philosophy of process integration, safety & environmentalprotection, high efficiency and low energy consumption, the project adopts a compact layout. Multiple safety facilities including CO-O₂ online monitoring system and CO₂ fire-extinguishing system are equipped in the system to provide multi layer safety guarantee for the pulverizedcoal preparation process. The whole production line realizes integrated control over the full workflow of coal drying, grinding, classification and conveying.

Supported by the PLC automatic control system, the project achieves on site unmanned intelligent production. Featuring easy operation and low failure rate, the system ensures non stop round the clock operation and greatly improves the continuity and working condition stability of the production line.

Case:

In the future, the enterprise will keep focusing on industry demands. By delivering more efficient, intelligent and eco-friendly systematic complete grinding solutions that precisely match kiln requirements, we will empower the high quality development of the lime industry.