Discussion on the structure of the methanation cycle gas compressor

In Nanyang, the 10 kV motor oil stations are located below, while the units have dry gas seals on the platform; the height of this platform is around 1.5 meters

The cycle compressor is a single-stage cantilever type, motor-driven; domestic production is sufficient

Introduction to the methanation injection cycle process. Basic methanation processes: 1. Through in-depth research and comparative analysis of the Topsoe methane synthesis technology and the Davy methane synthesis technology, we have gained a thorough understanding of the key aspects of both technologies. Topso technology is a good one, but it requires a high-pressure waste heat boiler; a high-pressure boiler must be installed for operation, and this brings numerous issues regarding construction and operational management. 2. Through actual operation, we found that the pressure drop in the methane reactor system is very low, ranging from 7–10 KPa; it is generally between 10–25 KPa, and even when it is higher, it stays within the range of 30–35 KPa. Coupled with our understanding of the theory behind injection technology as well as our many years of practical experience in its application, using the pressure of the desulfurized process gas as a driving force to enable an injection cycle process and eliminating the need for a cycle gas compressor represents a significant breakthrough in the methanation synthesis process. 3. We use a combination of multiple injectors to enable adaptation to different gas volumes while maintaining the same shape of the fluid ejected by the nozzles; flow rate adjustments within 10% of the total flow are carried out using needle-type regulation. II. Advantages of the jet cycle 1. The equipment investment cost is **reduced to about 1/3, and it requires less space. 2. Save electricity by transferring the power of low-efficiency circulators to high-efficiency large compressors ； 3. Being merely static pipelines, the number of safety management points is greatly reduced. 4. With no moving parts, compressor-related accidents are completely avoided; there is no need for maintenance nor associated costs, **which enhances the reliability of long-term operation. III. Projects Already in Operation 1. Shanxi Juyuan Coal Chemical – Explanation of Actual Operating Conditions and Data a. Initial design parameters (Northwest Research Institute):  Coke oven gas volume: 28,000 Nm3/h; actual volume: 14,500 Nm3/h ； No cyclic process;  Operational performance: The reaction temperature can reach up to 650°C, the catalyst needs to be replaced every 2–3 months, or at most every 6 months, which prevents stable production. b. Jet cycle modification: The jet cycle process was put into use in October 2016 ； The design cycle ratio is 1.0 v/v, with the reactor temperature controlled at 520°C. During actual operation, the recycle ratio was 1.3 v/v (1850/1400); the temperature in the first reactor was 461°C, and that in the second reactor was 456°C. After 1 year of stable operation, very significant results were achieved. 2. Operational status and data of Fuyangyuan in Xiangyuan, Shanxi a. Initial design parameters (New Earth Institute):  Coke oven gas volume: 18,000 Nm3/h ； Circulator power: 400kw × 2 units ；  Operational performance: The system operates without any issues. Compared to the jet cycle process, which has higher power consumption, the use of a mixed refrigeration (MRC) compressor in the preliminary processes such as compression results in a total power consumption of 2000 kW·h/t (1.379 kW·h/Nm3). Of this amount, the MRC compressor accounts for 600 kW·h/t (0.414 kW·h/Nm3), while the power consumption associated with the process itself is 1400 kW·h/t (0.966 kW·h/Nm3). This power consumption rate is 1.5 times higher than that of Jingbao’s 850–900 kW·h/t (0.58–0.62 kW·h/Nm3); it means 450 kW·h more per ton of LNG, resulting in over 16 million kW·h of additional energy consumption throughout the year. The initial idea was to apply various technologies from our previous energy-saving upgrades to the compressor systems of Jingbao Xin’ao, but it was later decided to use the jet cycle process first in order to address the issue of running the circulator and the heating furnace simultaneously. b. Modification of the injection cycle – Design concept: Respect the original process; air is introduced separately for the first and second reaction stages, following a two-stage circulation system, with a circulation ratio of 1.6 v/v for the first stage and 1.0 v/v for the second stage ； The total air intake volume is 16,000 Nm3/h; accordingly, the air intake volume for the first stage is 10,000 Nm3/h, and that for the second stage is 6,000 Nm3/h ； The reaction temperature is controlled at 500℃ ；  The ultimate goal is to shut down the recycle gas compressor and the heating furnace. Operation results: It was put into operation on September 2, 2017. The total desulfurization gas flow rate is 19,000 Nm3/h; the circulation ratio in the first stage is 2.0 v/v, and that in the second stage is 1.3 v/v ； Reactor temperatures: 432.70°C in Stage 1, 422.20°C in Stage 2, and 256.20°C in Stage 3. The reaction temperature is much lower than the designed value, resulting in excellent performance; the objectives of the retrofitting were thus achieved. Even when operating at a low load (9000 Nm3/h), with both sets of injectors in use (without any adjustments), the temperature in Stage 1 reactor remained at 432.70°C.

Thank you all very much; the ordering for the aircraft fleet is basically complete