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Water gas, due to its readily available raw materials, high calorific value, and high content of hydrogen and carbon monoxide in its gas composition, can be used as a high-quality gaseous fuel. It can also serve as a gas feedstock for industries that require hydrogen, such as ammonia synthesis and methanol production. Therefore, it is widely used in fields such as ammonia synthesis, ampule manufacturing, methanol production, and petroleum hydrogenation; especially in the fertilizer industry, semi-water gas serves as the feed gas for ammonia synthesis. Currently, the production processes for water gas include fixed-bed batch gasification, fixed-bed continuous gasification, fluidized-bed gasification, and fluidized-bed gasification. Domestic small and medium-sized ammonia synthesis plants, ammonia-alkali plants, methanol synthesis plants, and urban gas stations all use the fixed-bed batch gasification method, that is, the five-step gas production process, employing fixed-bed gasifiers ； A few large-scale ammonia synthesis plants use the fixed-bed continuous gasification method or the bubbling-bed gasification method, with Ruhr-type furnaces or bubbling-bed gasifiers; these approaches require significant investment, enable high production capacity, and are conducive to large-scale operations and automation. The fluidized bed gasification method is widely used abroad; a typical example is the K-T method, namely the K-T furnace. The five-step gas production process requires the least investment among all gas production methods. Over 70% of nitrogen fertilizer manufacturers in China use this process, which relies on fixed-bed gasifiers and has been in use for over half a century. With the continuous development of technology and the ongoing advancement of automatic control systems, this process has become increasingly mature, its various technical parameters have improved, and its application has become widespread. However, due to the inherent drawbacks of its process, multi-step cycles make it difficult to achieve efficient and rapid gas production; frequent valve switching at each stage results in time and gas consumption, low gas production efficiency, a complex process, low production efficiency, significant heat loss, and high energy consumption. The coal consumption per ton of ammonia produced in ammonia synthesis plants ranges from 1:1.25 to 1:1.35, whereas the theoretical value is 0.83 tons of standard coal per ton of ammonia; thus, the input-output ratio is only around 65%. Therefore, just as the steam engine was replaced by the steam turbine, a complete transformation of the process is necessary to bring about a revolution in coal savings. There have been no major breakthroughs in this technology abroad as well, and China’s national conditions mean that this technology cannot be phased out for a considerable period of time. Therefore, it is necessary to improve the five-step process used for intermittent gas production in fixed-bed systems in order to address the high consumption associated with this technology. The full name of the two-step water gas production process is: two-step fixed-bed lump coal oxygen-enriched gas production process. This process is a new and efficient gas production method developed to address the shortcomings of the five-step gas production process. It was created through numerous experiments, based on the experience gained from both batch gas production using fixed-bed reactors and continuous gas production with oxygen enrichment in fixed-bed reactors, as well as from experiments conducted in both forward and reverse directions. This process overcomes both the persistent problems of low carbon conversion rate and low thermal efficiency in intermittent gas production using fixed-bed reactors, as well as the issue of high carbon dioxide content in the water gas produced during continuous oxygen-enriched gas production with fixed-bed reactors, which requires expansion and modification of subsequent systems. This process still uses a fixed-bed gas furnace, with heated air being used for blowing; high-temperature superheated steam is employed for gas production, and an appropriate amount of oxygen is added to the steam during this stage (in ammonia synthesis, low-concentration oxygen-enriched air along with nitrogen is used) ； Special insulation treatment is applied to the additional boilers in order to reduce heat loss ； In this way, there are only two processes: short-term blowing and upward air generation. Compared to the five-step method, **it simplifies the process, improves the production efficiency of the furnace, eliminates the problems of low productivity and high consumption caused by frequent switching between the various steps in the five-step method, and overcomes the high oxygen production costs required for continuous oxygen-enriched gas production. If a renovation is carried out on an existing factory, the investment is low and results are seen quickly; minimal changes to the equipment are required, and it is easy to implement without disrupting production. Key features: low fuel and steam consumption ； High production efficiency per furnace ； The process is stable, with low residual carbon and no upward movement of the fire layer. Test results of the two-step process: 1. Gas analysis – the composition of water gas is 38–43% CO, 42–48% H2, 6–8% CO2, and 3–7% N2. Composition of the blowing gas: CO 7–9%, H2 1–3%, CO2 14–18%, N2 73–76%; comparison with the five-step process. 2. Cost analysis: Gas consumption for 1000 m3 – Two-step process: 460 kg of standard coal; Five-step process: 550 kg of standard coal. Oxygen consumption: 20 m3 in the two-step process, none in the five-step process. Steam consumption: 535 kg in the two-step process, 800 kg in the five-step process. 3. Comparison of process parameters: Two-step process vs. Five-step process – Steam decomposition rate (%): 60–66 vs. 40–44; Efficiency of the gas generator (%): 78 vs. 70. 4. Energy-saving analysis: The two-step gas generation process incorporates improvements in both equipment and process design, thereby enabling energy savings and reduced consumption: 1) Installation of internal insulation reduces heat loss, allowing for energy savings of 6–7% ； 2) Waste heat recovery is used for gas production to improve heating levels, enabling energy savings of 8~9% ； 3) Improvement of the gas generation process to enhance the heating capacity during gas generation, reduce residual carbon in the slag, and increase the steam decomposition rate, resulting in an overall energy savings of 10~11%. 4) With the simplification of the process, the equipment maintenance rate **decreases**, effectively increasing the actual production time. Advantages of the two-step water gas production process: Compared with the five-step process, the two-step water gas production process fundamentally eliminates the problems associated with the original process, such as complicated operations, frequent valve switching, which lead to low gas production efficiency, high heat losses, high energy consumption, and high equipment maintenance rates. It improves the efficiency of gas production and steam decomposition; the resulting gas contains high levels of hydrogen and carbon monoxide. The equipment operates smoothly with a low failure rate, fully meeting the needs of users, while also offering significant energy savings. Judging from the results of the renovation of the Φ1.8m water-gas generator at the gas station of Shanxi Ruicheng Hongguang Pharmaceutical Packaging Co., Ltd., the application effects are as follows: steam decomposition rate (%): around 62; total efficiency of the gas generator (%): 78; gas production volume (m3/h): around 670; coal consumption (Kg/Km3): around 465. Gas composition (%): H2: 42–48, CO: 38–43, CO2: 6–8, N2: 3–7. Compared with the five-step gas generator, it offers superior overall performance and achieves a savings of over 20% in energy consumption.