PSA hydrogen production

I suggest you find a few books and read more; it’s impossible to cover everything in a forum.

I. Process Flow The process flow of this unit is divided into three stages: the pressure swing adsorption hydrogen production stage, the deoxygenation and compression stage of the semi-finished hydrogen, and the evacuation and compression stage of the desorbed gas. ① PSA process: This process removes the vast majority of impurity components from the feed gas, while the hydrogen component is concentrated and purified there. This process is the core part of the entire facility; depending on the scale of the facility, it employs an 8-3-2/V operating process flow. The feed gas enters this unit at a pressure of 0.6 MPa(g) and a temperature of 40°C. After liquid substances are removed via the gas-liquid separator V0101, it passes through the flow control valve FICQ0101 and enters a pressure swing adsorption system composed of 8 adsorbers. At any given moment, 3 of these adsorbers are in use; the feed gas enters them from the bottom (the inlet side) through the corresponding 3 valves among KV101A-C-E-G-B-D-F-G. The adsorbers contain various adsorbent materials, and as the gas flows upward through the adsorption beds, impurity components are selectively adsorbed by the adsorbents. The hydrogen that has not been adsorbed exits from the top of the adsorbers through the corresponding 3 valves KV-102A-C-E-G-B-D-F-H, and then passes through the semi-product pressure control valve PICA203 to enter the semi-product buffer tank V0201, from where it is sent as crude hydrogen to the deoxygenation process. Each adsorber sequentially goes through steps such as adsorption (A), first-stage pressure equalization drop (E1D), second-stage pressure equalization drop (E2D), reverse pressure release (D), evacuation (V), second-stage pressure equalization rise (E2R), first-stage pressure equalization rise (E1R), and final pressurization (FR) at different times. All the pressure equalization drops in the adsorber are used for the pressure equalization increases in other adsorbers to fully recover H2 from the regenerating adsorber. The impurity components adsorbed in the adsorption tower are regenerated through steps such as reverse pressure release and vacuum pumping. II. Description of the process flow: The pressure swing adsorption section consists of eight adsorbers. The feed gas enters the three adsorbers that are in the adsorption stage through the feed gas valve KV101ACEGBDFH. Impurities such as CH4, O2, N2, CO, C3, and C4 are adsorbed by the bed layers, while the less strongly adsorbed component, hydrogen (containing a small amount of impurities), flows out from the top of the tower and exits through one of the outlet valves KV-102A-C-E-G-D-F-H. After pressure regulation using the adsorption pressure control valve PICA-203, this gas is sent to the deoxygenation system. The hydrogen entering the semi-product buffer tank V0201 is first heated to 80–100°C by the deoxygenation heater E0201 before entering the catalyst bed. Under the catalytic action of the palladium catalyst CNA561, the small amount of oxygen present in the hydrogen reacts with hydrogen to form water, thereby reducing the oxygen content to below 5 PPm. The hydrogen gas, with a temperature of 90–120°C upon exiting the deoxidizer, is cooled to ≤40°C in the deoxidizer cooler E0202. It then enters the deoxidation and water separation unit V0202, from where it is sent to the inlet of the product hydrogen compressor C0201AB via the product hydrogen buffer tank V0203. After being pressurized to 2.5 MPa by C0201AB, it is sent to the hydroprocessing unit or the reforming unit. The desorbed gas from pressure swing adsorption comes from the reverse discharge, vacuum pumping, and vacuum flushing steps. The gas with high pressure in the reverse discharge stage is desorbed through reverse discharge, and the corresponding two gases from KV-106A-C-E-G-D-F-H are sent to the desorbed gas buffer tank V0301 via the reverse discharge main valve KV-108. The back-pressure is lower during reverse playback. The gas in V0301 is controlled by the degassing pressure regulator PV-303 to enter tank V0302B. The desorbed gas from the vacuuming and vacuum flushing steps is drawn out through two corresponding ones of the vacuum desorption valves KV-103A-C-E-G-B-D-F-H, and is pumped by vacuum pump P0301 into the desorbed gas mixing tank (V0302A). There, the water entrained in the gas is separated, after which the gas is sent to the inlet of the desorbed gas compressor (C0302AB).

Although the process is a bit different, I still learned something. Everyone, please share as many suggestions as you can; thank you! :lol