Liquid holdup on the trays of the CO2 washing section in the main scrubber tower of coal chemical industry
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Our company uses the coal-to-gas process for producing synthetic ammonia. The facility is currently operating at near full capacity, but there is a liquid retention issue on the CO2 washing stage of the main scrubber tower. The current system pressure is around 2.9 MPa, and the amount of liquid washed by the system is approximately 230,000 cubic meters. I was wondering if any of you have encountered similar problems before?
It seems that the methanol in the tray cannot all flow down through the downcomer to the lower section; the liquid level control valve is already fully open, but it still doesn’t work – the volume has exceeded the allowable range!
It’s best if you take a photo and send it over; it’s necessary to consider your manufacturing process and specific circumstances in order to analyze it properly. It’s not easy to get it right just by guessing.
First, you should have confirmed that the control room setting matches the opening degree of the valves on site； Secondly, what is the amount of methanol you use for washing? Is it a single wash with lean methanol, or a wash using lean methanol combined with main washing methanol? Is the amount of washing too large? Once again, it’s unclear whether the distribution network for feeding methanol into the tower has been dislodged and entered the pipes, thereby reducing the flow rate in those pipes. We have encountered situations where the distribution packing was displaced, which led to a severe shortage of pump capacity.
First, you should have confirmed that the control room setting matches the opening degree of the valves on site； Secondly, what is the amount of methanol you use for washing? Is it a single wash with lean methanol, or a wash using lean methanol combined with main washing methanol? Is the amount of washing too large? Once again, it’s unclear whether the distribution network for feeding methanol into the tower has been dislodged and entered the pipes, thereby reducing the flow rate in those pipes. We have encountered situations where the distribution packing was displaced, which led to a severe shortage of pump capacity.
Photos cannot be uploaded, but it’s two types of methanol for washing; the one on top is the high-purity methanol!
This shouldn’t happen; currently, the amount of methanol used for washing is within the designed range, and we use nozzles instead of distribution networks.