The gasification unit of Huizhou Petrochemical’s Phase II gasification-based hydrogen production renovation project was successfully commissioned, thanks to the general contracting by Huisheng Engineering

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【Multiple Nozzles】The gasification unit of Huizhou Petrochemical’s Phase II hydrogen production project via gasification was successfully commissioned; Huisheng Engineering acted as the general contractor. Author/Source: Gasification World. Date: March 17, 2023. Clicks: 28. A grand commissioning ceremony was held on the morning of March 10, 2023, for the optimization and renovation of the hydrogen production facilities associated with Huizhou Petrochemical’s Phase II project. The Gasification Unit Series 5 was successfully started up with feedstock introduction at 19:05 on the day of the ceremony, while Series 6 was successfully started up on March 13, with the syngas being delivered smoothly to the downstream shift unit. The Huizhou Petrochemical Hydrogen Production Optimization Project adopts the multi-nozzle opposed gasification technology developed by East China University of Science and Technology; two additional gasifiers have been installed, resulting in a syngas production capacity of 140,000 Nm3/h. This project is the first time that Huisheng Engineering has undertaken a turnkey project under the BEPCC model within CNOOC’s system; the project contract covers tasks such as basic design, detailed design, procurement, construction, and commissioning. Since the start of construction of the main components of the gasification framework on May 10, 2022, it took only ten months to complete the project and bring it into operation, setting a new record for the construction time of similar facilities. The completion and operation of the Huizhou Petrochemical hydrogen production upgrade project provides a strong boost to the hydrogen demand required for the full-capacity operation of oil refining facilities, enhances the value of integrated petrochemical operations, and contributes significantly to the transformation of Huizhou’s energy structure as well as its sustainable, low-carbon development. On January 5, 2023, the intermediate handover for the optimization and renovation project of the hydrogen production facilities associated with Huizhou Petrochemical Phase II was completed as scheduled. The gasifier for the optimization and renovation project of the hydrogen production facilities associated with Huizhou Petrochemical Phase II was lifted into place in early September 2022; it took 120 days to complete, making it the first project to achieve completion in 2023. The hydrogen production in the second phase of Huizhou Refining and Chemical Plant utilizes the E-Gas coal slurry pressurized gasification technology developed by the American company CBI. Three gasifiers are employed (2 in operation and 1 as backup), along with a sulfur-tolerant shift reaction process featuring a low water-to-gas ratio, a Ruqi low-temperature methanol washing process, and PSA technology for the purification of hydrogen. The optimization upgrade involves adding 2 multi-nozzle water-coal slurry gasifiers, operating one in use and one as a backup; adjusting the existing 3 E-gas furnaces from 2 in use and 1 as a backup to 1 in use, 1 as a backup, and 1 under maintenance; as well as carrying out adaptive modifications to the supporting facilities. Project Overview: Currently, there are only two operating E-Gas coal-to-hydrogen plants in the world, which feature high carbon conversion rates, efficient heat utilization, and low oxygen consumption. Compared with traditional natural gas-based hydrogen production processes, it can reduce costs by 20%–25%. This facility ensures that pollutants such as nitrogen oxides, sulfur dioxide, and wastewater are discharged at levels that meet the specified standards, reaching an advanced level for the industry. The process system of E-Gas coal-to-hydrogen integrated plants is complex, and any issue in any part of it can affect the stable operation of the system, which is why many companies hesitate to undertake such projects. Since 2018, without any prior experience in operating coal-based hydrogen production facilities or having any trial operation experience, Huizhou Petrochemical, through continuous exploration and practice, has overcome a series of key technical challenges such as blockages in the tubes of waste heat boilers, high failure rates in carbon recovery systems, and ash accumulation in the second stage of the gasifier. It developed an automated control system for the entire gasifier process on its own, worked to localize the use of imported equipment such as backflow valves for coke filters, filter elements, and carbon recovery systems, and innovatively introduced fiber-optic temperature measurement technology. It also formulated operating methods for waste heat boilers and low-load operation procedures for sulfur units, enabling the safe and stable operation of the E-Gas coal-based hydrogen production complex under various load conditions. Since its commissioning in August 2018, the E-GAS gasification hydrogen production unit of Huizhou Refining & Chemicals Phase II has faced frequent system blockages, posing safety risks when operating under design conditions. As a result, the gasifier can only operate in a mode of one unit in use, one in standby, and one under maintenance; the amount of hydrogen and syngas produced is only half of what was designed, which severely affects the long-term stable operation of the hydrogen-consuming devices in the refining area. Moreover, the frequent start-up and shutdown cycles lead to large amounts of water gas being discharged directly into flares, increasing pollutant emissions. To address the aforementioned issues, CNOOC Huizhou Petrochemical plans to add 2 multi-nozzle water-coal slurry gasifiers, operating in a 1-in-service/1-backup configuration. The existing 3 E-gas hydrogen production units will be adjusted from a 2-in-service/1-backup setup to a 1-in-service/1-backup/1-under-repair arrangement, and the supporting facilities will undergo adaptive modifications. Upon completion of the modifications, the operating mode of the gasification-based hydrogen production plant was optimized to 2 in operation, 2 in standby, and 1 under maintenance. The production volumes of hydrogen and syngas were maintained at the levels specified in the environmental impact assessment for the second phase of the project, namely 151,400 tons of hydrogen and 119,000 tons of syngas per year. The design capacity of the gasification unit remains unchanged, while coal consumption decreases. The units related to the downstream stage of coal gasification, such as low-temperature methanol washing, acidic water stripping, and sulfur recovery, remain unchanged; there are no modifications to the materials flowing in and out or to the design capacity of these units. The new installations mainly include a multi-nozzle gasification unit, slag water treatment, sewage softening, a slag shed, and a 10kV substation. To make full use of the thermal energy of the water gas produced by the newly added multi-nozzle gasifier, a heat recovery system is installed, which can generate 64.0 tons/h of low-pressure steam at 0.4 MPa for use in the steam distribution network. With the E-gas vaporizer configured as 1 in operation, 1 in standby, and 1 under maintenance, the production of ultra-high pressure steam from heat recovery was reduced by 50%. Introduction to the existing coal-to-hydrogen facility in Huizhou Petrochemical Phase II: The coal-to-hydrogen process at CNPC Huizhou Refining and Chemicaling Phase II utilizes the E-Gas water-coal slurry pressurized gasification technology provided by the American company CBI, to produce 150,000 tons per year of hydrogen and 117,600 tons per year of carbonyl synthesis gas. Hydrogen is supplied to the refinery’s hydrogenation units, while syngas is used in the butyl octanol production units. Commissioned in 2018. According to the publicly released environmental impact assessment information on the optimization and renovation of hydrogen production facilities, the status of each process is as follows. Gasification: The hydrogen production via E-GAS coal gasification in the second phase of Huizhou Refining & Chemical Complex uses the E-Gas pressurized coal slurry gasification technology developed by the American company CBI. There are 3 gasifiers in operation (2 in use and 1 as a backup), with an effective gasification capacity of 264,000 m3/h. The main raw material is Shenfu coal. The coal gasification unit uses coal, water, and oxygen as raw materials to produce syngas through a partial oxidation process. After being washed, the syngas is sent to the downstream units for hydrogen production. A small amount of syngas drawn from the lower part of stage 1 of the gasifier is washed in the gasification unit using a Venturi tube and a countercurrent scrubber, before being sent to the extracted gas pretreatment unit for further washing and cooling. The conversion is carried out using a sulfur-resistant conversion process with a low water-gas ratio to produce syngas with a high hydrogen content that meets the CO concentration requirements. It includes the syngas modification section and the low-temperature heat recovery section. The processed raw material synthesis gas volume is 445,498 m3/h (on a wet basis), with the main product being 44.5×104 m3/h of shifted gas. Low-temperature methanol washing: The Ruchi low-temperature methanol washing process is used. It mainly includes transformed gas absorption, untransformed gas absorption, pre-wash liquid flashing, hydrogen sulfide flashing, carbon dioxide flashing, and thermal regeneration of methanol-rich liquid. The treated transformed gas volume is 42,4005 m3/h, and that of the untransformed gas is 20,995 m3/h. The pressure swing adsorption process is designed to produce 151,400 tons per year of industrial hydrogen with a purity of 99.9%. High-purity hydrogen is produced by using the PSA method for purification, with purified shift gas as the raw material. The purified exhaust gas is pressurized by a compressor and then sent to the plant’s fuel gas network. It includes PSA purification, exhaust gas compression, and the hydrogen addition section for purifying unreacted gas. For the refrigeration system, the freezing station utilizes propylene refrigeration technology to supply cooling capacity to the acid gas removal unit. The design provides a cooling capacity of 7400 kW. The device is formed by propylene compression and propylene condensation cooling. Acidic water stripping unit: The design capacity of the unit is 80 tons per hour for stripping the acidic water discharged from the gasification scrubber (Series 1), and 90 tons per hour for stripping the acidic water generated from process condensate, sulfur-tolerant shift, and low-temperature methanol washing (Series 2). Both Series 1 and Series 2 employ a single-tower low-pressure full-exhaust process. Acidic gas is sent for sulfur recovery, while the treated water is sent to the wastewater treatment plant and not reused. Sulfur recovery is designed with a capacity of 30,000 tons per year; under normal operating conditions, the sulfur production amount is 12,000 tons per year. The sulfur production section employs a modified CLAUS process consisting of a primary thermal reaction and two stages of catalytic conversion reactions. Tail gas combustion uses a thermal combustion process, while the flue gas is denitrified via SCR ； The ion liquid absorption section uses ion liquids to remove sulfur dioxide from flue gas. This includes sulfur production, flue gas combustion, liquid sulfur degassing and loading, ionic liquid absorption, and utility systems. Coal-to-hydrogen is an important approach to the efficient utilization of coal resources, offering competitive advantages in terms of safety and environmental protection, mature technology, and low cost. In the future, Huizhou Petrochemical will continue to advocate for the clean and efficient use of coal in the field of refining and chemical manufacturing, thereby contributing to the transformation of Huizhou’s energy structure and its sustainable, low-carbon development. The project is located in the Daya Bay Petrochemical Zone in Huizhou City, Guangdong Province. The total crude oil processing capacity of Huizhou Petrochemical’s Phase I and Phase II facilities is 22 million tons per year. Sinochem Sixth Construction is responsible for Section 3 of the new gasification unit project undertaken by CNOOC Huizhou Petrochemical Co., Ltd. Main products: refined petroleum products such as gasoline, coal oil, and diesel; PX chemical products; and ethylene raw materials supplied to CNOOC and Shell. The gasification hydrogen production unit is part of Huizhou Phase II project, and it includes units for E-GAS gasification, sulfur-resistant shift reaction, acidic gas removal, refrigeration, and pressure swing adsorption for hydrogen purification. It is reported that the total investment for this project is estimated at 676.8 million yuan, of which 83.4507 million yuan is allocated to environmental protection measures.