Cement plants need to use air compressors

Technical description on the application process of air compressor in cement plant

As a key power equipment in the cement production line, air compressors provide power support for core links such as material transportation, equipment driving, and process control by providing compressed air. The following specifications are given for its typical application scenarios and system configuration requirements:

1. Core process application scenarios

1. Powdered material conveying system：
   • Pneumatic conveying technology is used to convey cement clinker, coal powder and other powdery materials to designated locations through compressed air. This system can effectively solve the dust pollution problem existing in traditional mechanical transportation, and the transportation efficiency is improved by more than 40%.
   • Typical applications include key processes such as raw meal warehousing and transportation, clinker cooling and transportation out of the kiln, and cement finished products warehousing and transportation.
2. Process equipment drive system：
   • Provides power source for pneumatic valves, pulse dust collectors, air cannons and other equipment. In process links such as preheater clearing, grate cooler arch breaking, and humidifier tower water spraying, the response time of the compressed air-driven actuator is less than 0.3 seconds.
   • Key equipment configuration: pneumatic gate valve, pneumatic flow control valve, reverse blowing ash cleaning device, etc.
3. homogenization system：
   • In raw meal homogenization warehouses, cement storage warehouses and other links, compressed air is used for fluidization homogenization treatment. Air is distributed through a porous plate at the bottom to form a fluidized bed layer with a homogenization coefficient of more than 1.5.
   • Typical configuration: Roots blower air supply system, air distribution valve set, fluidized bed device.
4. combustion control system：
   • Provide combustion-supporting air for thermal equipment such as decomposing furnaces and rotary kilns. By accurately controlling air flow, complete fuel combustion is ensured and thermal efficiency is improved by 8%-12%.
   • Key parameters: Primary air volume control accuracy is ±2%, secondary air temperature is stable at 1050℃±20℃.

2. Expansion of special process applications

1. Humidifying tower spray system：
   • The compressed air drives the dual-fluid spray gun to atomize the process water to a particle size of less than 50μm to achieve flue gas cooling and dust capture. The system can reduce the flue gas temperature below 150℃ in 0.5 seconds.
   • Configuration requirements: air pressure 0.4-0.6MPa, flow adjustment ratio 1:10.
2. Online analysis and sampling system：
   • Provide backgas source for precision instruments such as X-fluorescence analyzers and particle size analyzers. Use 0.22μm precision filtration technology to ensure that the cleanliness of the sampling pipe meets the ISO 8573-1 Class II standard.
   • Key configurations: oil-free air compressor, stainless steel sampling probe, automatic blowback device.
3. Packaging and delivery system：
   • In the bag insertion and bag unloading process of the packaging machine, compressed air is used to drive the air cylinder, and the packaging efficiency can reach 120 bags per minute. At the same time, a dust removal fan is equipped to keep the dust concentration in the working environment below 2mg/m³.
   • Typical configuration: thin film cylinder, electromagnetic reversing valve, pulse dust collector.

3. System configuration specifications

1. Gas supply station design：
   • The compressed air station is centrally set according to the air consumption and adopts a modular design. The pressure fluctuation range of the main gas supply pipe network is controlled at ±0.05MPa to ensure stable operation of process equipment.
   • Typical configuration: 3-5 screw air compressors (including standby units), adsorption dryers, three-stage filtration devices.
2. Pipe network layout requirements：
   • The main pipe is made of DN150-DN300 seamless steel pipe, and the branch pipe diameter is selected from DN20-DN100 according to the air consumption. The slope of the pipeline shall not be less than 1:100 to ensure automatic discharge of condensate.
   • Key node configuration: automatic drainage valve, pressure gauge, temperature sensor, and maintenance valves are set every 100 meters.
3. quality control standard：
   • The quality of compressed air needs to meet the ISO 8573-1 standard: pressure dew point ≤-40℃, oil content ≤0.01mg/m³, and particulate matter ≤0.1μm.
   • Testing requirements: Check the pressure dew point every day, check the oil content every week, and conduct microbial culture testing every month.

4. Key points of operation and maintenance

1. daily inspection：
   • Record the exhaust temperature, pressure and oil level of the air compressor every 2 hours, and trigger a sound and light alarm when the parameters are abnormal.
   • Check the vibration intensity of the pipeline every day. When the amplitude exceeds 0.15mm, check the fixing status of the pipe clamp.
2. regular maintenance：
   • Replace the air filter element and oil filter every 2000 hours of operation, and replace the lubricating oil every 4000 hours.
   • The main engine of the air compressor is overhauled every year to test the rotor clearance. If the wear exceeds 0.2mm, it needs to be returned to the factory for repair.
3. energy-saving management：
   • Using frequency conversion speed regulation technology, the motor speed is automatically adjusted according to the air consumption, and the pressure can be reduced to 0.1MPa for standby during no-load periods.
   • Equipped with a waste heat recovery device, the exhaust heat of the air compressor is used to prepare 60℃ process hot water, and the measured energy saving rate can reach 15%-20%.

It is recommended that cement companies establish an energy efficiency evaluation system for compressed air systems and monitor specific power (kW/m³/min) indicators in real time by installing smart meters and flow meters. For continuous operation systems, a linkage control system can be configured to automatically start and stop the unit based on real-time pressure to control the number of operating units within the most appropriate range to achieve energy conservation and consumption reduction goals.