1000,000TPY Coal Powder Grinding Project
Design Scheme
Project Site: Shandong, China
Equipment: 4 MTW215 European Mills (Secondary Phase) and other auxiliary machines used for feeding, powder preparation, dust removal, powder collection, transportation, storage and nitrogen protection
Material: Coal
Finished Product: Coal powder
Input Size: ＜50mm
Output Size: 200meshes, D80
Capacity: 1,000,000TPY
Model of Efficient & Clean Use of Coal under Depression of Coal Industry
In response to national’s advocacy on clean use of coal, an energy company in Shandong purchased 4 MTW European Mills (secondary phase) for coal powder preparation from ZENITH. Through atomization of micro-coal, the coal will be supplied to industrial boilers as fuel. The use of coal powder can increase the combustion efficiency and thermal efficiency of boilers greatly and bring economic profits as much as hundreds of millions yuan. Undoubtedly, this is the model of efficient and clean use of coal.
Project Profile
Through the technology of micro coal atomization, the fuel can mix with air fully to form a rotary vortex and then the fuel enters the industrial boilers and burns in suspension inside. The use of thermal system, monitoring and controlling system and exhaust purifying system achieves the efficient combustion with emissions reaching the emission standards of gas.
Project Background
1. Depression of Coal Enterprises
Meanwhile, government actively advocates and supports the market-oriented reform and structural management in coal industry by releasing related policies. Under the condition of balancing supply and demand, it is urgent for coal industry to upgrade.
2. Support of National Policies
According to the fifth plenary of CPC’s 18th Central Committee, the clean use of fossil energy must be put on the schedule, coal included. So it can be concluded that the promotion of efficient and environmental coal powder boiler will be a key energy-saving technology.
3. Environmental Pressure
Using coal briquette as the fuel, traditional industrial boilers discharge a great deal of dust and contaminant. The emission of dust is ≤30mg/m3, SO2 ≤100mg/m3, nitrogen oxides ≤200mg/m3.
4. Economic & Environmental Profits
The use of coal powder boilers can burn over 98% of coal powder. Meanwhile, compared to the traditional boilers, the coal powder boilers can save energy by over 30% while heat efficiency keeps above 90%. The operation costs can be reduced by 20-30%.
Configuration Of Project
1. Main Equipment
The mill is equipped with the bevel gear integral transmission device, inner thin-oil lubrication system, monitor of oil temperature. Meanwhile, the mill boasts small occupation of land, low total investments, low operation costs, high efficiency and environment protection.
2. Auxiliary Machines
(1) Nitrogen Making System
Air enters the efficient oil remover. After that, the air-dryer removes most moisture and the powder filter. Then the air enters the air storage tank. After buffer, the air is sent into the nitrogen making machine. Clean compressed air enters to the adsorption tower. In the adsorption tower, the oxygen and nitrogen would be separated and the nitrogen would be sent to the tank for storage.
(2) Fire Extinguishing System
When the content of CO is beyond the preset-value, the alarm starts to send signal to the audible and visual alarm. Then the alarm counts down for 30s. When it counts down to 0, the alarm will send signal to the CO2 fire extinguishing system which is started to extinguish the fire.
(3) Pneumatic Conveyor
Pneumatic conveyor is mainly responsible for the transportation of coal powder. It can send the coal powder into the finished product bin from a long distance.
(4) Intelligent Centralized Control System
MTW European Mill has specialized intelligent control system. It takes ESC to control operation intelligently. And apart from the central control, it can control operation remotely.
Technological Analysis
Raw coal is sent to the scrapper conveyor for moisture removal. Then the coal enters the closed storage bin and transferred to MTW215 European Mill. After that, the coal powder undergoes the classification. The finished coal powder collected enters the elevator. The complete set of this system is equipped with the nitrogen making system and CO2 system to avoid explosion and to extinguish the fire if necessary.
Project Advantages
1. EPC Project
EPC service specially designed and offered to bring convenience to our customers. The service covers every and each stage of a project including the topographic survey, design of production line, test of raw material, the analysis of requirements on finished product, calculation of investment costs, installation of machines, and commissioning, etc.
2. Easy Operation
To make the operation easier, we took unique two-step method. Specifically, the two-step method refers to the solution which separates the drying process and powder preparation process. The system is simple and easy to be controlled.
3. Low Investment
The MTW European Mill is equipped with the bevel gear integral transmission device, inner thin-oil lubrication system, monitor of oil temperature. Meanwhile, the mill boasts low total investments, low operation costs, high efficiency and environment protection.
4. Safe & Environmental
To ensure safe operation during the coal powder preparation, the plant is equipped with nitrogen making system and CO2 fire extinguishing system in avoidance of explosion and fire accidents.
Analysis of Profits
(1) Analysis of Economic Profits
The atomization of micro coal can increase the combustion ratio to 98%, the thermal efficiency to 90%. Besides, steam production can be increased from 5.5 tons to 9 tons. Compared to the traditional industrial boilers, the clean coal powder boilers can save coal by 30%, electricity by 20%, water consumption by 10%, floor space by 60% and labor force by 50%. The sales volume of clean coal powder attains 800 million yuan and 100 million yuan of taxation of profit is got.
(2) Analysis of Social Benefits
The clean coal powder produced in this production line is supplied to the industrial boilers after the atomization of coal powder. It reduces the combustion of lump coal and urges coal industry to transform and upgrade. It is the model of clean use of coal.
(3) Analysis of Environment Benefits
All emissions met the standards of gas boilers, helping the environment protection.
Customer Feedback
This clean coal powder preparation production line was large and the requirement on quality of coal powder was quite strict, so we were very careful when we chose the machine manufacturers. After various inspections and analysis, we chose ZENITH. From the site survey to the commissioning, ZENITH offered us professional solutions and services. The 4 mills we purchased are running stably and the yielding is beyond our expectations.
Extended Reading
Introduction of Micro Coal Atomization
The key of this technology is atomizing micro coal by mixing it with the air vortex repeatedly. Mixing the micro coal (200meshes) with the high-speed air vortex is the first step. The mixture will be sent into the boilers and burn in suspension there. The use of thermal system, monitoring and controlling system and exhaust purifying system achieves the efficient combustion with emissions reaching the emission standards of gas.
Through selection, drying and grinding, the micro coal used in the efficient coal powder boilers can become the powder (200 meshes). Centralized management and unified delivery not only ensure the quality of coal powder but also eliminate the scattered coal piles. The boilers are characterized by high efficiency, environment protection, clean emission and high automation. Therefore, the promotion of efficient coal powder boilers plays an important role in clean use of coal, environment improvement and the growth of environment-friendly industries.
