Determination of the water vapor ratio in the carbon monoxide conversion section

The determination of the water vapor ratio in carbon monoxide conversion takes into account the following factors: 1. What is the raw material used for gas production in the previous process? Such as coal, or natural gas, or residue oil, etc. 2. Composition of the raw materials. For the same raw materials, different component combinations result in different choices for the water vapor ratio. 3. What is the transformation process? Depending on the conversion process (such as full low conversion, or medium-low-low conversion, etc.), the choice of water vapor ratio varies. 4. What is the gas generation process in the previous section? The water vapor ratio varies depending on the gas generation process.

Water vapor ratio, not water vapor ratio. The water-vapor ratio is roughly determined during the design phase. Calculations do not occur in actual production. There are no empirical formulas either. It mainly depends on whether the carbon monoxide content at the outlet is within the specified limits (to meet the requirements of the subsequent processing stage). The amount of vapor added is one of the important means to control the carbon monoxide content at the outlet. Of course, other process parameters at the workstation will be handled separately in case of abnormalities.

The main task is to determine the vapor-to-gas ratio for the first bed layer; this is done first through calculation, and then adjusted based on production experience. By determining the initial activity temperature at which industrial production with the selected catalyst of known model can begin, as well as the upper limit temperature that the catalyst can tolerate during its normal service life, and by using basic parameters, the steam-to-gas ratio required under these process conditions is calculated. Then, the results are adjusted based on actual production conditions; to some extent, this also involves making slight adjustments to the actual performance of products from different catalyst manufacturers of the same model. With this step, the remaining sections follow in the same manner.

The water vapor ratio is the ratio of the number of water vapor molecules in the inlet gas to the total number of dry gas molecules. The water-gas ratio (H2O/dry gas) is an important control parameter in the shift operation. According to the chemical equilibrium equations, an increase in the water-to-gas ratio raises the equilibrium conversion rate of CO, thereby accelerating the progress of the conversion reaction ； At the same time, a higher water-vapor ratio also has an inhibitory effect on side reactions. However, the consumption of water vapor is the main cost factor in the conversion process, and minimizing its usage is of great significance for the economic efficiency of the process. An excessive steam ratio will also lead to an increase in the resistance of the catalyst bed, a reduction in the CO residence time, and an increased load on the waste heat recovery equipment. The specific value of the water-vapor ratio needs to be determined based on process conditions, scale, and other factors. In our company, with a production capacity of 300,000 units, the designed value for the water-vapor ratio is between 3.6 and 4.5.