Which company’s technology is used for the 15MPa low-pressure ammonia synthesis process at Shandong Lianmeng Chemical?
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In November 2020, Shandong Lianmeng Chemical posted a second public notice on its official website regarding the environmental impact assessment for the upgrade project of the company’s 40·60 project’s clean production technologies. According to the public information, the Shandong Alliance has upgraded the traditional fixed-bed batch gas production process by using space powder gasification, low-temperature methanol washing, and liquid nitrogen washing technologies. Upon completion of the renovation, the production capacity for synthetic ammonia and methanol remains unchanged at 400,000 tons per year of liquid ammonia and 200,000 tons per year of methanol. Contents of the renovation project: Construction of 2 space furnaces for gasification. The model is φ3200/3800. Process 3,000 tons of coal per day (on a dry basis). The gasification furnace load is 76.06% (the remaining load is reserved for subsequent projects of the Alliance Group, with separate environmental impact assessments to be conducted for those projects). The conversion is carried out using a Co-Mo-based conversion catalyst in an isothermal conversion process. Two sets of isothermal conversion units will be constructed, with the diameter of the conversion furnace being φ3600. Low-temperature methanol washing includes processes such as desulfurization and decarburization, CO2 desorption, H2S concentration, and methanol thermal regeneration. Construct 2 methanol wash absorption towers, 1 CO2 desorption tower, and 1 methanol thermal regeneration tower. Gas purification uses liquid nitrogen washing. Install 1 nitrogen scrubber tower. Ammonia synthesis employs a low-pressure synthesis process of 15 MPa. One set of φ2800mm ammonia synthesis towers is installed, with an ammonia synthesis production capacity of 400,000 tons per year. The internal structure of the ammonia synthesis tower is of the “three beds, four sections, quasi-full radial layer, inter-stage heat exchange” type. Methanol synthesis produces methanol through the combined production process of hydrogen-rich off-gas and raw gas for low-temperature methanol washing. Lixiu currently has 2 100,000-ton/year low-pressure polyol production units, and it has phased out the high-pressure polyol and alkylation units. The air separation process uses an internal compression air pressurization cycle expansion scheme. Air is frozen and separated into liquid oxygen and liquid nitrogen; at the same time, the argon in the air is also frozen to become liquid argon. The oxygen production capacity through air separation is 55,000 m3/h.
Long time no see. Are you referring to the wall thickness of the synthesis tower? ? ?
I’ve always thought that φ3200/3800 can be understood as a wall thickness of 300 mm – that’s comparable to the armor on battleships
It can’t be thought that way; there are also components such as water wall tubes
I’ve always thought that φ3200/3800 can be understood as a wall thickness of 300 mm – that’s comparable to the armor on battleships. I’m not quite clear about this; is it thicker at the top and thinner at the bottom?
On November 27, 2014, Nanjing Jutuo Chemical Technology Co., Ltd. announced that the industrialization project of the software package for the 600,000 tons per year low-pressure ammonia synthesis process technology, which was developed independently by the company, had been successfully put into operation at Runyin Biochemical Co., Ltd. under Shandong Ruixing Group. This facility has been operating at full capacity for over a month now, proving that the technology for large-scale low-pressure ammonia synthesis has reached an internationally leading level. It has set a world record for the daily production of ammonia under the same gas conditions, opening up a new path for the scaling up and localization of ammonia synthesis technology in China. It is reported that this is the first ultra-large-scale ammonia synthesis project in the country to utilize fully independent intellectual property technology; its engineering design takes into account a process with virtually no inert gases, with an ammonia production capacity of 900,000 tons per year. Currently, the plant operates using an inert gas system, and the daily production of synthetic ammonia has exceeded the target of 2,400 tons. Among them, key equipment such as the DN3200 ammonia synthesis reactor, lotus-shaped direct-connected waste heat recovery unit, and modular ammonia cooler, which were independently developed, designed, and manufactured by the company, operated smoothly during the initial commissioning process; their performance met advanced technical standards, even exceeding the design specifications. The operation of this device marks a significant breakthrough in China’s technology for scaling up key equipment in ammonia synthesis systems. It is reported that the cooperation agreement for this project was officially signed in January 2010; it was fully completed on October 12 of this year, and started operating successfully upon the first batch of materials being fed in, achieving stable operation with all process and technical parameters meeting or exceeding the design requirements. Currently, the methane content in the recycle gas of the ammonia synthesis system is 15.1%, the synthesis pressure is 13.65 MPa, the system resistance is 0.86 MPa, and the average daily production of ammonia is 2,112 tons. Lu Jian, chairman of Nanjing Jutuo, told a reporter from China Chemical Industry News that the industrialization project of this low-pressure ammonia synthesis process technology software package received strong support from Shandong Ruixing Group Runyin Biochemical Co., Ltd. Through the joint efforts of relevant technical personnel, all the technologies involved in this 600,000 tons per year low-pressure ammonia synthesis process technology software package were successfully overcome. Lu Jian said that the large-scale low-pressure ammonia synthesis technology developed by the company has three advantages: first, the \"quasi-fully radial, three-bed four-stage, detachable\" ammonia synthesis tower features a high ammonia yield, low resistance, uniform temperature distribution across the bed layers, and the ability to replace catalysts in stages ； Secondly, the ammonia synthesis tower is connected directly to the waste heat recovery unit, resulting in minimal heat loss and enabling the production of high-quality medium-pressure steam ； Thirdly, the modular ammonia cooler combines devices such as the three-stage ammonia cooler, the three-stage ammonia flash tank, and the heat exchanger into a single unit; once in operation, it not only boasts excellent technical performance but also reduces investment costs significantly, offering notable energy-saving benefits.