Discussion on Energy Saving of cement injection Screw Air CompressorDate: 2019-06-20 Views:
Cement production is a highly energy-consuming industry. The biggest challenge in cement plant is energy consumption(thermal energy and electric energy consumption), accounting for about 50%~70%of production cost. In recent years, central and local governments have strengthened control over energy-intensive cement industries, requiring improvement of ecological benefits and sustainability, and issued rules and regulations and fines, urging cement enterprises to reduce energy consumption and carbon dioxide emissions. Therefore, how to explore the energy consumption of cement in depth and improve the efficiency of energy use is a problem to be faced by every cement enterprise.
In the general cement plant, the power consumption of the air compressor is 20-25% of the total power consumption of the plant, and if the power consumption of the air compressor is reduced by 15%, the total power consumption of the factory can be reduced by 2-3%.
The purchase of air compressor opportunity results in a large purchase cost, but this cost only accounts for 7% of the air compressor cost, and the maintenance cost of the air compressor is only 8%. The most difficult to pay attention to is the electricity charge consumed by the air compressor, accounting for 85% of the use cost of the air compressor in the whole life cycle.
From all aspects, reducing the cost of power can effectively save energy.
1.the current situation of air compressor is tested by energy-saving diagnostic equipment.
Determine whether an air compressor is energy-saving, and check the energy efficiency limit value and energy efficiency level>of GB191532009
Second, the replacement of more energy-saving units;
Due to the progress of technology, now two-stage compression, permanent magnet frequency conversion can easily achieve level 1 energy efficiency, or even more than level 1 energy efficiency.
The two-stage compression reduces the compression ratio of each stage, reduces the internal leakage, improves the volume efficiency, reduces the bearing load, and improves the life of the main engine. The two-stage compression replaces the single-stage compression, and the exhaust volume is increased by nearly 15%, which can achieve up to 15% energy saving effect.
Because of its excellent motor efficiency and saving the energy consumption of air load conversion of ordinary units, permanent magnet frequency conversion unit can also greatly improve the operation efficiency of the machine and save energy consumption. In a cement plant in Sichuan, our company replaces 4 air compressors produced by a certain brand with an Yonites UDT110 two-stage compression permanent magnet variable frequency screw air compressor. The operation shows that the customer opens a production line to save 1200 degrees a day, and two lines to save 600 degrees a day, and the energy saving effect is very remarkable!
3. improve the air compression pipeline system to achieve the best state;
Air leakage is a direct waste, resulting in pressure drop in the compression pipeline, resulting in pressure of the air compressor, every kilogram of pressure, the energy consumption of the system increases by 7%, and increases the maintenance and maintenance costs at the same time. The larger the pore size and pressure, the more leakage volume. 1. Mm small hole leakage cost is about 2700 yuan a year!
4. Effective use of linkage control system;
When multiple air compressor units work at the same time in cement plant, the joint control system can give full play to the energy saving effect to the greatest extent. by monitoring the pressure of the system in real time, it stops the operation of unnecessary air compressor and controls the number of air compressor running units in the most suitable range. In the past, a factory used four ordinary air compressors of 37kW, one of which was replaced with one of the two-stage compression permanent magnet variable frequency screw air compressor and added to the joint control program, saving 160000 yuan a year!
5. to maintain and maintain the air compressor to save energy.
If the internal filter of the air compressor is clogged, the energy consumption will increase. For example: oil blockage. Because of blockage, there will be pressure loss, and this pressure drop must be pushed up by compressor to make the system pressure reach the required value. When the three filter pressure drop reaches 1bar, the energy consumption of the system needs to be increased by 7%, resulting in energy consumption loss. Take the 37kW machine as an example, running 7200 hours a year and consuming about 18000 degrees more per year.
In summary, all factory equipment managers can check that your air compressor has reached the level 1 energy efficiency level? Does your air compressor system match reasonably? Is your air compressor pipeline system reasonable? Is your air compressor system in place for Nissan management?
For bag dust removal and instrument gas system, there are the following main problems:
1. Most of the machines are more than 8 years of equipment, and some of the air compressors have served for more than 13 years;
2, there are many single screw compressors, the gas volume attenuation is serious, the energy consumption is huge;
3, almost all the compressors are used for pressure reduction, and the internal pressure of the air compressor system is generally higher than that of the gas storage tank (0.1MPa).
4, most systems have no frequency converter, the gas supply pressure is higher than the demand pressure, and a small number of systems have compressor unloading.
5. there is a large pressure difference in the gas transportation pipeline, which improves the operating pressure of the whole system in order to meet the normal operation at the end of the system, resulting in great waste.
The post-treatment equipment (cold dryer, filter, etc.) in the system is basically unmaintained, and more than 80% of the equipment is in a stagnant state, which not only can not achieve the predetermined goal of water removal, but also increases the pressure loss of the system and reduces the passage.