Low-pressure separator

The high-temperature section has a high control temperature, and the opening degree of the pressure control valve in the low-pressure separator is large； At high thermal scores, the control temperature is low, and the opening degree of the pressure control valve in the low-pressure separator is small.

I feel that in terms of the metrics, a higher value for pressure control opening corresponds to greater pressure, which may indirectly indicate an increasing reaction depth, while a lower value may indicate a decreasing reaction depth. 2. Have the upstream heat exchanger fins or air-cooling louver blades been moved? An increase in temperature after cooling will cause the pressure control valve of the low-pressure separator to open wider, while a lower temperature after cooling will cause it to close gradually. 3. Check whether there is cross-pressure during the liquid discharge operation in the dehydrogenation unit; if the low-pressure separation pressure suddenly increases during this operation, it is necessary to consider the possibility of cross-pressure as well as the accuracy of the level gauge in the dehydrogenation unit. 4. If the back route is not unobstructed, gradually increasing the flow rate on the other side helps to determine whether there is an obstruction in the desulfurization pipeline due to low pressure, or whether ammonia salts are causing blockages. If both the flow meter and the pressure in the back route for desulfurization gradually decrease, while the pressure controlled by the valve for low pressure continues to rise despite this, and no change occurs even after opening an alternative route, then it is necessary to consider the possibility of a blockage. In short, the level of voltage control corresponding to low scores is generally one of the best indicators for reflecting the degree of depth; please forgive any mistakes in what I’ve said.

If there is more light component and the depth is greater, one can refer to the opening degree of the liquid control valve

Shouldn’t the opening angle of a deep-depth hydraulic control valve be reduced?

The large variation in the opening degree of the low-pressure control valve is mainly due to the fact that sometimes there is only one valve position, or the valve even shuts off intermittently; at certain times, however, its opening degree can reach over 140%, approaching 50%

As the depth increases, the cold low-pressure liquid control valve opens more, while the hot low-pressure liquid control valve closes more

The low score is mainly due to the condensation of recycled hydrogen; temperature control is key.

Why do cold lows get larger? Won’t it also produce small molecules or gas phase?

The pressure control valve of the low-pressure tank in the hydrogenation unit operates in a direct-acting manner: as the pressure increases, the valve opening increases, and vice versa. In the case of low-pressure tanks, with a constant operating temperature, the level of pressure directly indicates the degree of reaction depth; the higher the degree of reaction depth, the more light components are present, and thus the pressure increases ； With a low reaction depth and few light components, the pressure is low. When the pressure-controlled valve is operated in automatic control mode, it shows that: at high pressure, the valve opening is large; at low pressure, the valve opening is small.

Should the hydraulic control valve be opened or reduced?