Material balance
Thread Content
This post was last edited by reelove on 2015-10-24 at 15:42. The vacuum level in the device’s pressure relief flash tower is currently 30 KPA. The heat exchanger fed into the tower is at the same height as the top of the tower; everything worked fine during the water-based operation phase, but now that oil is being used for operation, the material balance cannot be maintained. Simply put, there is too much residue in the pipeline; the pump filters for feeding and discharging often get clogged, which results in a reduction in flow rate. The feed flow meter also fails to display flow rates intermittently, with only the discharge flow meter functioning properly. It might be due to the vacuum level; as a result, after the feed pump stopped operating, the liquid level in the tower continued to rise, which led to one instance of the tower being flooded. Later, after reducing the vacuum level to 10 kPa, this problem disappeared. However, for normal production the vacuum level needs to be between 50 and 70. Now the pump fails to create sufficient vacuum, and the tower gets flooded. What should be done going forward? Furthermore, when transporting oil currently, it’s impossible to determine the material balance points for feeding and discharging. The discharge volume is fixed, and no matter how the feeding volume is adjusted, the liquid level cannot be stabilized – it either drops steadily or rises steadily. The valve opening has to be adjusted by jumping between 10% and 80% in order to prevent sudden changes in the liquid level, which is really troublesome! Please share some suggestions; there are 2 questions, I hope you can help!
Please check the quality of the oil; this kind of problem shouldn’t occur
With the recycling of used oil, that’s the quality of the oil that results
Before entering the vacuum flash tower, the raw material is filtered through a filter with a high mesh size to remove impurities. A Blue-type filter with an open-filter plate is used at the pump inlet.
Set the feed control valve to manual mode, find the valve position that results in the smallest fluctuations, and then switch it to automatic mode. Of course, the prerequisite is to find a way to keep both the pump flow rate and the column pressure stable. It is also best to check whether there is any blockage in the diaphragm at the site of the differential pressure level gauge.
Generally, there are many impurities in the initial stage, which can easily cause blockages in instruments, valves, etc.; therefore, inspection and cleaning are necessary. . . . . . . . . . . . .
Close the upper and lower valves of the on-site level gauge, remove the diaphragm box, clean it, and then reinstall it; I suspect that the delay in the liquid level indication is the cause of the problem.