Compressed air has become an indispensable form of energy in many production processes due to its cleanliness and safety. It is even called the fourth energy source. In most manufacturers, the energy consumption of compressed air accounts for 10%-35% of total energy consumption. Through the statistics of the air systems of various industries, the vast majority of compressed air systems, whether new or old, operate Unsatisfactory efficiency—compressed air leaks, artificial gas, incorrect use, and inadequate system control all result in reduced efficiency. This means that improving the operating efficiency of the compressed air system plays a very important role in saving energy consumption of the air compressor and increasing labor productivity. According to China's energy-saving project "zhong" motor system energy saving "an important part. 1 Introduction to the analysis method of energy saving potential of compressed air system This paper conducts continuous on-site inspection of the use of compressed air system in the production workshop of a manufacturing company in Shanghai, collects system pressure and current data, and establishes the energy consumption baseline of compressed air system. Multi-point recording equipment is installed at the job site to collect various key data, and finally the performance curve of the existing system is obtained. After understanding the operating characteristics of the system, through a series of professional analysis, combined with the basic principles of compressed air, find opportunities for energy saving and enhance the reliability of the system. 2 Overview of compressed air system The air compressor station in the production workshop of the company is equipped with 5 Atlas oil-injected screw air compressors with a total installed capacity of 190 kW. Among them, GA-ll (24.5L/S, llkW) 2 is dry. Equipment, air compressor back end is equipped with a gas storage tank. Compressed air is mainly supplied to the workshop cylinders and pneumatic tools, and the cylinder gas requirements are. 5-0.6Mpa, pneumatic pressure requirements for pneumatic tools are 3 compressed air system test analysis During the test process, the production tasks of the workshop are normal, and the test results can reflect the actual production conditions. The pressure and air compressor current data of the compressed air system in the processing workshop are as follows and shown below: 1. The operating pressure diagram of the air compressor is shown from the data curve in the above figure. At present, the current and air pressure of the air compressor fluctuate too much, so There is a certain energy-saving space, and the instability of the current is caused by the instability of the air pressure. The instability of the air pressure is caused by excessive gas consumption or leakage. It can be seen that there is obvious adjustment and unloading adjustment. And very frequently. The screw air compressor of the company currently adopts the on/off adjustment (on/off adjustment) control mode. When the compressor is unloaded, it still consumes about 35% of the power at full load, and the compressor does not produce gas at this time. The test pressure sampling point is at the gas storage tank of the system. The air compressors of 1, 2 and 5 are supplied one-to-one to the gas equipment. The current average pressure is 6.5 bar, and the maximum pressure is 8.1 bar. Most of the time, it is in the state of loading and unloading. Pressures that exceed actual pressure requirements can cause more energy wastage for the system. According to the operating experience, the pressure difference is 1bar, the energy consumption can vary by 7%-15%. 4 Compressed air system optimization scheme design According to the above data and analysis, it is recommended to use the air compressor high-efficiency frequency conversion control system and the central control system to make the gas supply. The system is better matched according to the actual needs of the system, stabilizes the supply pressure, improves the efficiency of the compressor at partial load, reduces energy consumption, and reduces the labor load of the air compressor station staff. 4.1 Installation of frequency conversion high-efficiency control system According to the characteristics of system flow load change, the air compressor can be modified with high-efficiency energy-saving controller, so that it has the function of speed control, the gas production is proportional to the speed, and the air compressor is adjusted after the transformation. The problem that the compressor is less efficient under partial load due to the unloading control mode can be avoided, and the supply air pressure can be made more stable than the loading and unloading mode. 4.2 Installation of intelligent centralized control system The compressor intelligent centralized control system is used to control the Atlas screw air compressor. The intelligent centralized control system can comprehensively control the screw compressor according to the pressure demand of the air compressor system. The operation of the air compressor. 4.3 Other system optimization recommendations Energy waste due to leakage is considerable. According to statistics, the leakage in the factory usually accounts for 10-30% of the gas supply, and the poorly managed factory may even be as high as 50%. The leakage problem is common in Cylinders, solenoid valves, pneumatic valves, air handling components, etc. In the case of leakage, more than 90% of the leakage is due to aging or damage to the components in use. Some professional monitoring equipment such as parallel access intelligent gas leak detectors, leak point scanning guns, etc. can be used to take measures to prevent the running, running, dripping and leaking of the compressed air system, and carry out maintenance work and component replacement work accordingly. According to the system test results and analysis, based on the economic and practical principles, it is proposed to install energy-saving measures such as variable frequency high-efficiency control system, centralized control system and end leakage treatment. It is estimated that the energy saving rate of the compressed air system can reach 40%. 28.3 million KWh, which is expected to save about 90,000 yuan in electricity costs annually. 5 Summary At present, the annual power consumption of air compressors in China is close to 300 billion kWh. The energy consumption of compressed air systems in modern industrial sites can not be ignored. Energy-saving transformation and improvement of its operating efficiency will become industrial energy-saving. An important task, which has enormous economic and social benefits, and contributes to the realization of the national energy conservation goals during the 12th Five-Year Plan period. 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