CN-120425366-B - Alkaline electrolysis hydrogen production system

CN120425366BCN 120425366 BCN120425366 BCN 120425366BCN-120425366-B

Abstract

The invention belongs to the field of electrolytic hydrogen production, and discloses an alkaline electrolytic hydrogen production system which comprises an alkali liquor circulation loop, an oxyhydrogen separation loop, a hydrogen deoxidation drying loop and a cooling water circulation loop, wherein the alkali liquor circulation loop comprises an electrolytic tank, a hydrogen precooler, an oxygen precooler, a hydrogen separator, an oxygen separator and an alkali liquor cooler, alkali liquor from the hydrogen separator and the oxygen separator enters the alkali liquor cooler, is subjected to secondary cooling by cooling water from the cooling water circulation loop, enters the electrolytic tank to carry out electrolytic hydrogen production, then enters the hydrogen precooler and the oxygen precooler, is subjected to primary cooling by the cooling water from the alkali liquor cooler, realizes gradient cooling in a cooling mode of carrying out a two-time heat exchange process, furthest carries out heat recovery in the electrolytic hydrogen production process, improves the heat exchange efficiency of the system, and can reduce the load of subsequent oxyhydrogen separation and hydrogen drying treatment by using the recovered heat to preheat hydrogen, and further reduces the energy consumption of the system.

Inventors

RONG YANGYIMING
Ma Qinhui
FANG HAO
FENG BIAO
LIU QIUHUA
MA SHIHAO
LI CHENGJUN
GAO JUN
ZHU BO

Assignees

中国电建集团华东勘测设计研究院有限公司

Dates

Publication Date: 20260505
Application Date: 20250512

Claims (8)

1. An alkaline electrolytic hydrogen production system, comprising: The system comprises an alkaline liquor circulation loop, an anode outlet of the electrolytic tank, an alkaline liquor inlet of the oxygen precooler, an alkaline liquor outlet of the oxygen precooler and an alkaline liquor inlet of the oxygen separator, wherein water in the alkaline liquor is subjected to decomposition reaction in the electrolytic tank, a cathode outlet of the electrolytic tank is communicated with the alkaline liquor inlet of the hydrogen precooler, an alkaline liquor outlet of the hydrogen precooler is communicated with the alkaline liquor inlet of the oxygen precooler, an alkaline liquor outlet of the hydrogen precooler and an alkaline liquor outlet of the oxygen separator are both communicated with the alkaline liquor inlet of the alkaline liquor cooler, and an alkaline liquor outlet of the alkaline liquor cooler is communicated with the electrolytic tank; The hydrogen-oxygen separation loop is communicated with the hydrogen-oxygen separation loop and can separate hydrogen from oxygen; the hydrogen deoxidation drying loop is communicated with the hydrogen deoxidation drying loop and can dry the separated hydrogen; The cooling water circulation loop is also communicated with the alkali liquor cooler, a cooling water outlet of the alkali liquor cooler is respectively communicated with a cooling water inlet of the hydrogen precooler and a cooling water inlet of the oxygen precooler, and the cooling water outlet of the hydrogen precooler and the cooling water outlet of the oxygen precooler are both communicated with the cooling water circulation loop; The hydrogen-oxygen separation loop comprises a hydrogen cooler, an oxygen cooler, a hydrogen scrubber, an oxygen scrubber, a first gas-liquid separator and a second gas-liquid separator, wherein the hydrogen cooler is positioned at the top of the hydrogen separator and is communicated with the first gas-liquid separator, a gas-liquid outlet of the hydrogen cooler is communicated with a gas-liquid inlet of the hydrogen scrubber, and a gas-liquid outlet of the hydrogen scrubber is communicated with a liquid return port of the hydrogen separator; the hydrogen outlet of the hydrogen scrubber is communicated with the first gas-liquid separator, and the liquid outlet of the first gas-liquid separator is communicated with the water return port of the hydrogen separator; The oxygen outlet of the oxygen scrubber is communicated with the second gas-liquid separator, the oxygen outlet of the second gas-liquid separator is communicated with an external collecting pipeline, and the liquid outlet of the second gas-liquid separator is communicated with the water return port of the oxygen separator; the hydrogen deoxidization drying loop comprises a first preheater, a hydrogen heat regenerator, a deoxidization heater, a deoxidization tower, a first cooler, a second cooler, a third gas-liquid separator, a fourth gas-liquid separator, a three-tower drying system, a regeneration heater, a second preheater and a hydrogen filter; The hydrogen outlet of the first gas-liquid separator is communicated with the hydrogen inlet of the first preheater, the hydrogen outlet of the first preheater is communicated with the low-temperature inlet of the hydrogen heat regenerator, the low-temperature outlet of the hydrogen heat regenerator is communicated with the inlet of the deoxidizing heater, the outlet of the deoxidizing heater is communicated with the inlet of the deoxidizing tower, the outlet of the deoxidizing tower is communicated with the high-temperature inlet of the hydrogen heat regenerator, the high-temperature outlet of the hydrogen heat regenerator is communicated with the hydrogen inlet of the first cooler, the hydrogen outlet of the first cooler is communicated with the inlet of the third gas-liquid separator, the hydrogen outlet of the third gas-liquid separator is communicated with the inlet of the three-tower drying system, and the three-tower drying system can dry the separated hydrogen.
2. The alkaline electrolysis hydrogen production system of claim 1, wherein the lye outlet of the hydrogen separator and the lye outlet of the oxygen separator are both communicated with the lye inlet of the lye cooler by a lye circulating pump.
3. The alkaline electrolysis hydrogen production system of claim 1 wherein the hydrogen cooler is connected to the hydrogen separator with a flange and the oxygen cooler is connected to the oxygen separator with a flange; the hydrogen scrubber and the oxygen scrubber both comprise a scrubber shell and a cooling coil pipe arranged in the scrubber shell, and the cooling coil pipe is communicated with an external pipeline by utilizing a flange on the side wall of the scrubber shell.
4. The alkaline electrolytic hydrogen production system according to claim 1, wherein the three-tower drying system comprises a first drying tower, a second drying tower and a third drying tower, wherein a hydrogen outlet of the third gas-liquid separator is communicated with an inlet of the first drying tower, an outlet of the first drying tower is communicated with an inlet of the hydrogen filter and a hydrogen inlet of the second preheater respectively, a hydrogen outlet of the second preheater is communicated with a hydrogen inlet of the regeneration heater, a hydrogen outlet of the regeneration heater is communicated with an inlet of the second drying tower, an outlet of the second drying tower is communicated with a hydrogen inlet of the second cooler, a hydrogen outlet of the second cooler is communicated with an inlet of the fourth gas-liquid separator, a hydrogen outlet of the fourth gas-liquid separator is communicated with an inlet of the third drying tower, and an outlet of the third drying tower is communicated with an inlet of the hydrogen filter.
5. The alkaline electrolysis hydrogen production system of claim 1, wherein the first preheater, the second preheater, the hydrogen precooler and the oxygen precooler are shell-and-tube heat exchangers; And the low-temperature side of the first cooler and the second cooler is cooled by chilled water at 7-12 ℃.
6. The alkaline electrolysis hydrogen production system of claim 1 wherein the cooling water circulation loop comprises a cooling water supply header and a cooling water return header; The cooling water inlet of the lye cooler is communicated with the cooling water supply header pipe, the cooling water outlet of the lye cooler is respectively communicated with the cooling water inlet of the hydrogen precooler, the cooling water inlet of the oxygen precooler and the water side inlet of the first preheater, the water side outlet of the first preheater is communicated with the water side inlet of the second preheater, the water side outlet of the second preheater is respectively communicated with the inlets of the cooling coils of the hydrogen scrubber and the oxygen scrubber, the water side outlet of the second preheater is also communicated with the cooling water return header pipe, the outlets of the cooling coils of the hydrogen scrubber and the oxygen scrubber are respectively communicated with the cooling water inlet of the hydrogen cooler and the cooling water inlet of the oxygen cooler, and the cooling water outlet of the hydrogen cooler and the cooling water outlet of the oxygen cooler are communicated with the water side inlet of the first preheater; And the cooling water outlet of the hydrogen precooler is communicated with the cooling water return header pipe.
7. The alkaline electrolysis hydrogen production system of claim 6, wherein the cooling water outlet of the hydrogen precooler is communicated with the cooling water outlet of the oxygen precooler, and then communicated with the cooling water return main pipe by a water return pipeline, and a first flow valve is arranged on the water return pipeline; The water return pipeline is communicated with a water side inlet of the second preheater by a water return branch pipe, the water return branch pipe is positioned at one side of an outlet of the first flow valve, and a second flow valve is arranged on the water return branch pipe; a shut-off valve is arranged between the water side outlet of the second preheater and the inlets of the cooling coils of the hydrogen scrubber and the oxygen scrubber.
8. The alkaline electrolysis hydrogen production system of any one of claims 1 to 7 further comprising a controller, wherein the lye circulation loop, the oxyhydrogen separation loop, the hydrogen deoxygenation drying loop, and the cooling water circulation loop are all communicatively coupled to the controller.

Description

Alkaline electrolysis hydrogen production system Technical Field The invention relates to the technical field of electrolytic hydrogen production, in particular to an alkaline electrolytic hydrogen production system. Background Along with the green hydrogen industry as an important carrier of a clean energy system to enter a rapid development stage, the alkaline water electrolysis hydrogen production technology becomes one of main flow routes of large-scale hydrogen production due to the advantages of mature technology, controllable cost and the like. However, in the process of the industrial development to large and intensive, the traditional alkaline electrolysis hydrogen production system exposes a remarkable technical bottleneck, wherein the traditional device mostly adopts a distributed small-scale design, the hydrogen production energy consumption per unit of the electrolysis process is generally maintained in a 4.3-4.8kWh/Nm 3 high-level range, and a remarkable gap exists between the traditional device and an energy-saving target below 4.0kWh/Nm 3 expected by the industry. A large amount of low-grade waste heat of 30-80 ℃ can be generated in the operation of an electrolysis system, and the existing cooling scheme generally adopts single-temperature cooling water prepared by an air cooling tower to directly exchange heat, so that multiple links of cooling water such as an electrolysis tank, a separation device, an alkali liquor circulation system and the like are repeatedly consumed, and the mixing loss of heat energy at different temperature positions is caused. The alkaline electrolysis hydrogen production system consumes 30-40 tons of water for producing 1 ton of hydrogen, wherein about 50% of water resource consumption is caused by evaporation loss in the cooling process of the air cooling tower. The rough heat management mode not only aggravates the waste of water resources, but also reduces the overall energy efficiency of the system, and severely restricts the large-scale commercial application of the alkaline electrolysis hydrogen production technology. Disclosure of Invention The invention aims to provide an alkaline electrolysis hydrogen production system, which solves the problems of the related technologies, recycles heat in the hydrogen production system and saves the energy consumption of the system. In order to achieve the above object, the present invention provides the following solutions: The invention provides an alkaline electrolysis hydrogen production system, which comprises: The system comprises an alkaline liquor circulation loop, an anode outlet of the electrolytic tank, an alkaline liquor inlet of the oxygen precooler, an alkaline liquor outlet of the oxygen precooler and an alkaline liquor inlet of the oxygen separator, wherein water in the alkaline liquor is subjected to decomposition reaction in the electrolytic tank, a cathode outlet of the electrolytic tank is communicated with the alkaline liquor inlet of the hydrogen precooler, an alkaline liquor outlet of the hydrogen precooler is communicated with the alkaline liquor inlet of the oxygen precooler, an alkaline liquor outlet of the hydrogen precooler and an alkaline liquor outlet of the oxygen separator are both communicated with the alkaline liquor inlet of the alkaline liquor cooler, and an alkaline liquor outlet of the alkaline liquor cooler is communicated with the electrolytic tank; The hydrogen-oxygen separation loop is communicated with the hydrogen-oxygen separation loop and can separate hydrogen from oxygen; the hydrogen deoxidation drying loop is communicated with the hydrogen deoxidation drying loop and can dry the separated hydrogen; The cooling water circulation loop is also communicated with the alkali liquor cooler, the cooling water outlet of the alkali liquor cooler is respectively communicated with the cooling water inlet of the hydrogen precooler and the cooling water inlet of the oxygen precooler, and the cooling water outlet of the hydrogen precooler and the cooling water outlet of the oxygen precooler are communicated with the cooling water circulation loop. Preferably, the alkali liquor outlet of the hydrogen separator is communicated with the alkali liquor inlet of the alkali liquor cooler by an alkali liquor circulating pump. Preferably, the hydrogen-oxygen separation loop comprises a hydrogen cooler, an oxygen cooler, a hydrogen scrubber, an oxygen scrubber, a first gas-liquid separator and a second gas-liquid separator, wherein the hydrogen cooler is positioned at the top of the hydrogen separator and is communicated with the first gas-liquid separator, a gas-liquid outlet of the hydrogen cooler is communicated with a gas-liquid inlet of the hydrogen scrubber, and a gas-liquid outlet of the hydrogen scrubber is communicated with a liquid return port of the hydrogen separator; the hydrogen outlet of the hydrogen scrubber is communicated with the first gas-liquid separator, and the liquid outle