Liquid level control of the ammonia cooler in low-temperature methanol washing
Thread Content
The normal liquid level range for the ammonia cooler in low-temperature methanol washing is 30–80 cm, with an alarm set at 90 cm. Is the cooling capacity higher when the level is near 30 cm or near 80 cm?
A high liquid level in the ammonia cooler results in better cooling performance. But it is related to the pressure of the ammonia cooler at that time. The liquid level should not be too high, as this can cause the compressor to operate with liquid inside it.
I think a high liquid level should affect the flashing space for liquid ammonia, right? And it also affects the area available for heat exchange with the heat transfer medium
A slightly higher liquid level is better, but the level should be determined based on the temperature required by the medium being cooled. A too high liquid level is also not ideal, as it reduces the space available for the evaporation of liquid ammonia, thereby reducing the cooling effect.
I don’t think the level of the liquid has much to do with the cooling efficiency; it is the ammonia cooling pressure that matters. High pressure, excellent cooling performance ； Conversely, the cooling effect is poor. This is just my personal opinion for reference only. :lol :lol :lol
I also think that the level of the liquid has no direct relation to the cooling efficiency. The liquid level is too high; the flash space is limited, which makes it easy for liquid to enter the ice maker
Take a look here to see if it’s helpful: http://bbs.hcbbs.com/viewthread.php?tid=374694&highlight=%B0%B1%C0%E4%C6%F7
The liquid level in the ammonia cooler is generally controlled at around 50%; this is done to increase the heat exchange area. If the heat exchange efficiency of the cooler is poor, one can first increase the liquid level, secondly drain waste from the ammonia cooler to improve its purity thereby enhancing the heat exchange performance, and thirdly clean the cooler
I believe that either too high or too low a liquid level in the ammonia cooler results in poor heat exchange efficiency; an appropriate liquid level is one that just reaches the level of the tube bundles. Of course, the location of the liquid ammonia inlet in the ammonia cooler is also closely related to the suction pressure of the ammonia ice machine
Ugh, how can it be okay? The liquid level is high; mainly because the heat exchange area has increased
If there is data, it can be calculated. At a 30% liquid level, evaporation is the main process; the heat absorbed through evaporation, Q1, can be calculated based on the evaporation area, flow rate, and temperature difference. The heat exchanged, Q2, can be determined using the heat exchange area corresponding to 30%. The sum of these two values represents the total heat absorbed. Similarly, it can also be calculated based on 80% heat exchange area and 20% evaporation; by comparing this with the previous method, it is possible to determine which approach yields better results. However, a high liquid level can cause liquid to enter the compressor inlet, leading to various hazards.