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Luoyang Jianlong Successfully Completed the Replacement of Molecular Sieves in Xinjiang Guanghui’s 60,000 Nm3/h Air Separation Unit / Author/Source: Special Gas Network / Date: 2019-07-01 / Clicks: 38. On June 28, it was reported by Luoyang Jianlong Micro-Nano New Materials Co., Ltd. that the project to replace the molecular sieves in Unit B of Xinjiang Guanghui New Energy Co., Ltd., a project handled by its Sales Department III, was successfully completed with the replacement carried out and the unit put back into operation. For detailed operating parameters, please refer to the table below. It is reported that the medium molecular sieve purification unit of Unit B with a capacity of 60,000 Nm3/h at Xinjiang Guanghui New Energy Co., Ltd. originally used a vertical radial flow single-bed design from a foreign company (with molecular sieves imported as original equipment). The molecular sieve used in this replacement is the JLDL-2 type vertical radial-flow specialized molecular sieve from Jianlong Micro-Nano. High-temperature activation and regeneration were completed on June 14-15, and it began operation during the night shift on the 15th. By the 17th, the gas flow rate had increased to over 300,000 Nm3/h, and all parameters measured at the outlet met the requirements specified in the technical agreement; thus, the startup was successful from the first attempt. Compared with horizontal adsorbers, vertical radial-flow single-layer bed adsorbers have the advantage of a simpler structure. The molecular sieve exhibits good co-adsorption properties for water and carbon dioxide, which reduces the amount of molecular sieve required; as a result, the size of the equipment can be decreased ； The disadvantage is that molecular sieves have a stronger water absorption capacity than alumina; the energy required for regenerating molecular sieves to release trapped water is higher than that needed for activated alumina. The mechanical strength of the water-absorbed portion of the molecular sieves decreases, and they tend to become powdered, which ultimately affects their overall service life. Taking into account these characteristics of vertical radial-flow single-layer bed adsorbers, the R&D department at Jianlong Micro-Nano launched a specific project in 2016 to develop a high-performance molecular sieve named JLDL-2, based on the existing JLOX series of molecular sieves. This new material boasts a high adsorption capacity, high compressive strength, and excellent desorption performance. Launched in January 2017, it offers the following advantages over other high-performance molecular sieves available on the market: 1. It uses X-type raw powder synthesized through a special process, which increases its specific surface area and thereby enhances the adsorption and desorption rates ； 2. By utilizing unique shaping and calcination techniques, the dynamic adsorption capacity of the molecular sieve is improved, while energy consumption during the desorption process is reduced as well ； It effectively reduced the impact of the co-adsorption of water and CO2 on the strength of the molecular sieve, **decreasing its pulverization. In addition, the project for the optimization and modification of the purification system as well as the procurement of molecular sieves for the 52,000 Nm3/h air separation unit of Yunnan Tianan Chemical Co., Ltd., which is also handled by the Third Sales Department of Jianlong Micro-Nano, involved the supply of the entire set of equipment by Air Liquide (Hangzhou) Co., Ltd. in 2004; the air treatment capacity of this unit is 315,000 Nm3/h, and it consists of vertical radial-flow double-bed adsorbers. Jianlong Micro-Nano won the bid for this project on September 25, 2017, and the optimization and renovation work was completed in May 2018. The project utilizes Jianlong Micro-Nano’s JLDL-2 high-efficiency molecular sieve; it has been in operation since June 2018, with good performance to date. Since then, Jianlong Micro-Nano’s vertical radial-flow specialty molecular sieves have been successfully applied in Linde’s vertical radial-flow single-bed adsorbers and Air Liquide’s vertical radial-flow double-bed adsorbers, representing another successful example of Jianlong Micro-Nano achieving innovation in product applications and technological transformation – shifting from a specialized molecular sieve manufacturer to a technology service provider. For a long time, foreign air separation equipment manufacturers such as Linde and Air Liquide have held a high market share; their equipment is generally of 40,000 Nm3/h or higher capacity. The market for the use and replacement of molecular sieves is dominated by foreign companies specializing in molecular sieves, and the localization of this replacement process for such equipment is progressing slowly. Jianlong Micro-Nano stated that the company will continue to explore the specific requirements of large-scale air separation equipment regarding molecular sieves, actively work to optimize processes and solve problems for domestic air separation clients, and strive to make greater contributions to the localization of molecular sieves used in such large-scale air separation equipment, thereby facilitating import substitution.