The opening of the liquid nitrogen throttle valve not only affects the reflux ratio of the upper tower, but also affects the reflux ratio of the lower tower. When the opening is increased, the reflux ratio of the upper tower increases, while the reflux ratio of the lower tower decreases, the purity of the nitrogen in the upper tower increases, and the purity of the oxygen enriched night sky in the lower tower increases. However, after the opening is over, the purity of the liquid nitrogen decreases, and the reduction of the reflux ratio of the upper tower is also detrimental to the improvement of the purity of the liquid oxygen. Therefore, an equilibrium point should be found for the opening of the liquid nitrogen throttle valve. We can generally use the purity difference between liquid nitrogen and gas nitrogen to judge whether the opening is appropriate. Generally, the purity of the sprayed liquid nitrogen is equal to that of the upper tower gas nitrogen or the liquid nitrogen is slightly lower, indicating that the opening of the throttle valve is appropriate.
The second stage of DEAR intelligent control system will achieve accurate prediction and active regulation of local equipment. By collecting and analyzing the comprehensive data of different regions (including altitude, air temperature, air humidity, sunshine time, etc.), machine learning can be accurately related to the external environment of different regions. Achieve two purposes: 1. Accurately predict the safe service life of equipment operation in different regions, the best maintenance cycle of components, and the output and working conditions affected by seasonality; 2. According to the seasonal influence in a year, the operating parameters of the equipment are actively regulated.
