Shenzhen huaxing photoelectric technology co., LTD., as a leading high-tech enterprise and industrial base of LCD panel display in China, has established an unshakable leading position in the industry with its product technology, production process, production capacity design and new product development. The cooperation with huaxing opto-electronics is no longer unfamiliar. Since 2014, T1, T2, T3 and the recent T6 project, our constant theme is to provide customers with the most energy-saving solutions.
In the construction project of the tft-lcd (including oxide semiconductor and AMOLED) production line of the 85th generation of huaxin optoelectronics, the customer's on-site air compressor adopts the combination mode of 15 (centrifuge ZH15000) +2 (oil-free screw ZR315). After using it for more than a month, according to the customer's feedback, during the month, the CDA flow is 145,000 CMH ~ 181,000 CMH, and the instantaneous flow fluctuation reaches 15,000 CMH. There are a lot of emptying phenomena in the actual operation, and the energy waste is serious.
Through the analysis of the operation status, we know:
1) wide flow fluctuation range
According to the flow record chart provided by the customer, the fluctuation range in the actual operation is very large, with the maximum flow of 181065.5m /h, the minimum flow of 144712.9m /h, and the average flow of 162314m /h. The maximum fluctuation range is 36352.6m /h, and the average fluctuation range is 18064m /h.
2) high flow fluctuation frequency
According to the flow record chart provided by the customer, the gas consumption fluctuates very frequently in the actual operation process. There is no stable period of flow during the whole operation process, and the flow is always in a state of frequent fluctuation. Air compressor needs frequent adjustment, or can not be adjusted resulting in vent adjustment. In addition, the field screw machine flow is too small, can not meet the current flow fluctuation range adjustment.
3) long time emptying
According to the user's field application description, due to the high frequency and wide range of flow fluctuation, the air compressor has been using the operation mode of 11+1 or 12+1 (one centrifuge is the idling hot standby machine and the screw machine is rarely opened), resulting in a centrifuge (hot standby machine) being in the state of blowdown for a long time and causing a large amount of energy loss.
Therefore, it can be basically judged that the screw machine collocation is not reasonable. Because the configuration of screw machine ZR315 is too small, two screw machines can only cover 38% of a single centrifuge, which cannot play an ideal regulating role, so customers seldom use it.
We also analyze the energy consumption. According to the practical calculation results of energy consumption and energy consumption of centrifuge design, we found that customers using the actual consumption is higher than design energy consumption by around 10%, equivalent to about 10% of the average volume is in the field is empty, this means that there is always the flow of a centrifuge is in the empty state, this result is consistent and customer actual running situation (1 centrifuges for idling hot standby was empty).
Based on the above situation, we put forward an optimization plan, adding two ZR900VSD oil-free variable frequency screw air compressors to replace one centrifugal air compressor, without the need for hot standby machine. The fluctuation range (about 18000m /h) of the oil-free frequency conversion screw adjusting system can reduce the frequent adjustment and emptying of the centrifuge.
New scheme, the traffic using the centrifugal air compressor (10 or 11), range adopts oil-free frequency inverter control of screw, the centrifugal air compressor running under the most efficient at full capacity, volatility part adopts frequency conversion efficiency, continuous adjustment method, which can fully meet customer actual moment after 18000 m/h range, and good use of the centrifuge in full load operation under the condition of high efficiency and stability. At the same time, two oil-free screw rods are used to replace one centrifuge in operation, and the hot standby machine is cancelled, which can not only achieve the function of regulating the flow rate, but also avoid emptying.
In the new scheme, the oil-free frequency conversion screw ZR900VSD adopts frequency conversion to adjust the fluctuating flow, cancelling the hot standby machine and directly avoiding the phenomenon of a large number of blowdowns on site. Under the best working condition, it is estimated that it can save 18208.8KWh/ day directly for customers, and at 0.6 yuan /KWh, it can save 3,987,727 yuan for customers in a year.