Some issues regarding driving
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1. When operating a low-temperature engine, water intercooling is required, and this process needs to be repeated 3 or 4 times. Where should all that water be discharged to? If water intercooling is carried out in winter, could the water freeze? How should this be dealt with? 2. Why is propylene fed into the quencher slowly during gas introduction, rather than all at once? 3. What temperature range is suitable for feeding heat to the reboiler of the heat regeneration tower when establishing a methanol cycle, and where are the measurement points located? 4 Why cannot nitrogen gas be introduced when the liquid level in the concentration tower has not been established?
The regeneration tower should be put into operation once the temperature in the washing tower drops to -20 degrees; nitrogen for stripping can generally be introduced half an hour before gas introduction. Propylene should be introduced slowly; if too quickly, it will cause the compressor to shut down. The water in the system does not freeze easily as long as it is in motion; for example, our operating equipment has parts that are cooled by water. The way to prevent freezing is to keep a certain flow rate of water flowing through these systems.
When the wash tower reaches -20 degrees, the temperature in the regeneration tower should be at a certain level by then. Isn’t the reboiler being brought online gradually? Could the temperature of methanol in the heat regeneration tower end up below the minimum temperature set for that tower, thereby causing damage to the tower’s material?
1. The water is discharged directly into the ditch; it shouldn’t freeze if the volume is large enough. 2. The introduction of propylene should be slow; if it is too fast, the compressor cannot handle it, and secondly, the temperature difference in the heat exchanger is too large. 3. When cooling down, the activation of the thermal regeneration tower should be determined based on the temperature at the inlet of the methanol pump; if this temperature is too low, activating the regeneration tower and the pump will be problematic ； It’s too high; using a pump in such conditions can easily lead to cavitation. It is also not conducive to cooling. 4. The nitrogen stripping gas can be put into use before introduction; during cooling, it is sufficient to maintain the pressure in the concentration tower.
1. During water intermodal transport in the north during winter, water coolers are prone to freezing, which may also damage the pipes. The gutters may freeze up during discharge. Generally, antifreeze agents such as low-carbon alcohols and diols can be added. 【It is recommended to use ethanol; although it is more expensive, methanol is harmful to humans.】 2. One issue is equipment stress, and the other is that propylene gas will vaporize rapidly, resulting in liquid carryover. 4. Operating the nitrogen stripping system too early results in waste of nitrogen, and the exhaust gases may also contain methanol, thereby contaminating the environment ； It is too late to achieve the purpose of pre-cooling the inlet cooler. 3. Please let an expert answer instead. . .
May I ask, where is the monitoring point for reducing the temperature of the absorption scrubber to -20 degrees? Is it at the bottom and top of tower T101? Also, when T101 cools down to -20 degrees, what is the temperature of the methanol in T104?
Regarding the fourth issue, introducing nitrogen for stripping during level establishment can have an impact on the internal components of the tower; since nitrogen can easily push the tray plates over due to the pressure of the liquid
This phenomenon will not occur as long as the liquid level does not rise above the nitrogen inlet!