Feed separation tank for sulfur-resistant shift reaction

Don’t you mix steam before making the change?

No, the steam mixture was placed after one transformation

What is separated is the condensate; the liquid that is separated out is water vapor. When calculating the water-to-vapor ratio, we are referring to water vapor, not liquid water.

If there is no separation tank, before entering the next stage, must the crude syngas pass through a syngas heater – can the condensate be heated into steam in this process?

It then depends on the amount of condensate; too much of it is not acceptable. We have heaters and water separators before the converter inlet, but there have been cases where water entered the converter due to water in the vaporization zone.

Can liquid condensate be carried in the process gas even under normal operating conditions? If not, is it possible to do without a separation tank?

If no separator is used and heat exchange is not possible during the initial gas introduction, the condensate will inevitably be carried into the reactor and soak the catalyst.

The ratio of water vapor coming from vaporization must be relatively high, right?

Generally, gas-liquid separation tanks should be installed on the feed lines of the conversion units, whether it is the first, second, or third conversion unit. Its main function is to prevent excessive liquid in the intake air from causing problems, as well as abnormal operation of the heater, which could lead to the accumulation of liquid in the feed pipeline and the formation of slug flow ； Furthermore, the liquid enters the conversion reactor, causing foaming of the catalyst and leading to a deterioration in operating conditions.

Here are a few points to consider: 1. First, for the shift reaction in fixed-bed batch gas production and coal gasification processes, external steam is required to adjust the water vapor ratio; whereas for the shift reaction in slurry coal gas production, no steam needs to be added, as the water vapor present in the coal gas itself is sufficient to meet the production requirements. A small amount of the condensate water in water gas may vaporize in the heat exchanger, having little effect on the water-to-gas ratio in the conversion process ； However, those that do not have time to vaporize are carried into the catalyst layer, causing caking and scaling of the catalyst as well as the loss of active components, which leads to a decline in the catalyst’s activity. 2. Furthermore, high temperatures and pressures, in the presence of water, can easily cause corrosion at the welds on the tube sheet of heat exchangers, leading to internal leakage in the tubes of the heat exchanger. Therefore, not separating the condensate is purely harmful with no benefits at all.