Gas variation in hydrogen production units
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I would like to ask that in a dry gas hydrogen production plant, since the medium-pressure reformate exits the medium-pressure reformer and then goes directly to the PSA unit for purification, and the PSA unit has very strict requirements regarding water content, how is the water content in the medium-pressure reformate controlled? Should it be controlled in the upstream units, during the steam supply process in the conversion system?
After the medium-pressure reactor, there is a cooling zone before reaching the PSA
The temperature of the medium-temperature gas coming out of the medium-temperature reactor is over 400 degrees; after a series of heat exchange and liquid separation processes, it reaches room temperature with an extremely low water content before entering the PSA unit. There is also a raw gas liquid separation tank before the gas enters the PSA adsorption towers.
After being produced in the medium-pressure shift unit, the gas undergoes a series of heat exchange and cooling processes, as well as water-gas separation, before entering the PSA unit. The temperature at which it enters the PSA unit depends on the efficiency of the water cooler’s heat exchange capabilities, as well as on the control of the water-to-gas ratio in the medium-pressure shift unit!
Medium-pressure gas treatment mainly involves dehydration using medium-pressure gas coolers and liquid separation tanks.
The PSA unit is equipped with a desiccant to absorb saturated water vapor. It is advisable to install a plate-type cooler with low-temperature water at 6–9 degrees, along with a gas-water separator, before feeding the medium-pressure gas into the PSA unit; this can significantly reduce the moisture content in the gas fed into the PSA.
What to do about the water-to-carbon ratio? Don’t they know about separation tanks, air cooling, and water cooling? I’m a bit speechless:L
Primarily, it must be cooled to below 40°C before entering the PSA; only after complete liquid separation can it proceed into the PSA
Before entering the PSA unit, isn’t there a series of heat exchangers? There are also several separation tanks for water removal; once the temperature drops to 40 degrees, there’s basically no water left before entering the PSA unit
Behind the medium transformer there is a cooler, and behind the cooler lies the medium transformer water separation tank; it is sufficient to control the liquid level in this tank as well as the temperature of the fluid entering the PSA unit.