Some people have analyzed the air compressor, the power consumption of the air compressor is very large, but it can not be used, researchers are also studying energy-saving air compressors, constantly updating equipment, resulting in high energy consumption of air compressors for the following reasons:
1. Low equipment efficiency
Most of the air compressors installed a few years ago are low-energy equipment,The device does not match the terminal properly,Just to meet the basic needs of production;The adjustment mode of air compressor is backward and there is no centralized control,When the gas consumption changes randomly,The air compressor is seriously wasted due to unloading;The gas used by the terminal equipment is unreasonable, the efficiency is low, and the gas used by the equipment is wasted。
2. Unreasonable gas supply pressure
There is no hierarchical planning of gas supply pressure, but simply adopts high pressure gas supply plus mechanical self-operated pressure reducing valve to meet different pressure needs, and a lot of energy is wasted on the valve。In addition, when the demand side gas consumption changes cause random fluctuations in the pipe network pressure, in order to avoid frequent start and stop of the unit, it is necessary to set a wide range of pressure changes, resulting in large fluctuations in the outlet pressure of the air compressor, increasing the operation energy consumption of the air compressor system。
3. Causes of energy waste
High no-load energy consumption
At present, most enterprise compressors are single N cubic, and the compressor starts and stops only N or multiple of N, and the air compressor equipment starts and stops relying on the tradition of manual management。Especially when the gas load changes frequently, the system cannot react quickly, nor can it achieve the fine tuning of the compressor displacement, which forms the no-load of the compressor in the air compressor station。
Under normal circumstances, when the pressure reaches y kg, the air compressor enters the unloading operation state, when the pressure is reduced to x kg, the compressor enters the no-load state, that is, the intake valve is closed so that the motor is in an idling state, and the excess compressed air in the oil pre-separation tank is discharged through the vent valve。Closing the intake valve to make the motor idle although the air compressor does not need to compress the gas for work, the air compressor still needs to drive the screw or piston to do rotary movement in idle, and the power consumption continues to occur。The actual test found that the energy consumption of the air compressor under no-load is as high as 40% ~ 55% of its full load operation。
High climbing energy consumption
Screw compressor has two operating modes, adding, unloading operation mode or no-load, full load operation mode。The loading and unloading control mode makes the pressure of the compressed gas move back and forth between x kg and y kg。x kg is the lowest working pressure value, that is, the lowest pressure (loading pressure) that can ensure the normal operation of the user.。Under normal circumstances, the relationship between x kg and y kg can be expressed by the formula: y kg =x kg +(1+δ), δ is a percentage, its value is roughly between 10% and 25%。The pressure difference is generally more than one kilogram。Through theoretical calculation and practical testing, it is learned that for every 1kg increase in air compressor pressure, energy consumption increases by 5-6%。
It can be seen that in the air compressor under the loading and unloading gas supply control mode, its working pressure is from x to y, and there is an energy consumption of pressure climbing, and there is actually energy waste。At the same time, before the gas above x kg enters the gas terminal, its pressure needs to be reduced by the pressure reducing valve to close to x kg, the higher the pressure, the faster the flow rate, which results in the same working condition, the higher the pressure, the greater the gas consumption。The process is also a waste of energy。
Traditional management
In the use and management of air compressor station, there are two unavoidable contradictions。One is that the enterprise has a clear assessment of the air compressor management personnel, then the air pressure is often not enough or the habit of opening less, which is not conducive to the normal operation of the production line, or the pressure can not meet the requirements of the use of equipment, resulting in an increase in the failure of the gas terminal。One is that there is no clear assessment of air compressor managers, which will lead to more air compressors and high no-load energy consumption of air compressor stations。No matter what kind of management mode, the result will be that the waste of electric energy in the air compressor station will increase, and it is not conducive to safe production。