What is the impact of high and low temperatures of the coal pulverization pressurized gasification agent on gasification production?

If the temperature of the gasifying agent is high and, after heat exchange with the ash, the temperature of the ash drops only slightly, this may lead to overheating of the ash lock； A low temperature of the gasifying agent can lead to an increase in coal consumption; furthermore, it may result in the formation of wet ash, making it difficult to discharge the ash. It is also stated that a low temperature of the gasifying agent can lead to the formation of condensate, causing corrosion on the grate and at the bottom of the gasifier.

What is the impact of high and low temperatures of the coal pulverization pressurized gasification agent on gasification production? ...A high temperature of the gasifying agent indicates a large amount of steam being added, which is beneficial for preventing the furnace temperature from exceeding T2 through solid slag removal, thus ensuring the normal progress of the gasification process ； The temperature of the gasifying agent indicates the amount of steam added; a lower temperature is beneficial for raising the furnace temperature in solid slag discharge furnaces, but it should not exceed T2, so as to ensure the production of high-quality gas.

The temperature of the vaporizer is directly related to the amount of gas generated in the jacket.

This post was last edited by shuker666 on 2019-10-23 at 12:39. As already mentioned above, I’d like to share my perspective. A high temperature of the gasifying agent can be intuitively understood as an elevated gas-oxygen ratio, which means an increased amount of steam entering the furnace. When the gas-oxygen ratio does not match the operating conditions, it can lead to a situation where both temperatures in the gasification furnace are higher than normal (the ash lock temperature and the outlet temperature of the gasification furnace). This results in an increase in the production of gas and water, with the ash taking on a fine-grained form. The ash lock is prone to clogging, and in severe cases, the temperature of the coal lock may also rise. If there is too much water in the coal on a basis weight basis, the coal lock is likely to clog, and if this situation isn’t addressed over time, it will lead to uneven distribution of the gasifying agent, further worsening the operating conditions； The low temperature of the vaporizing agent contradicts this; the oxygen-to-gas ratio is low, but the temperature of the vaporizing agent must be 20°C higher than the saturated vapor pressure at that pressure. Otherwise, the presence of liquid water can cause severe damage to the grate (leading to cracks in it). When the oxygen-to-gas ratio remains low for an extended period, the temperature of the combustion zone inside the furnace rises, resulting in large lumps of ash and slag. This causes serious damage to the grate and scrapers, as well as excessive wear on the valves used to control ash flow, thereby reducing the service life of these components. Failing to make adjustments over time also leads to uneven gas distribution, resulting in the phenomenon of \"double highs\". Both have an impact on the gas outlet composition ； In short, an oxygen-to-coal ratio that does not match the load and coal quality should not be maintained for long periods; it needs to be adjusted promptly. Otherwise, uneven gas distribution can lead to a deterioration in operating conditions, and in severe cases, problems such as uneven burning and channeling may occur. Therefore, the grate used in coal gasification can rotate in both directions (functions of the grate: breaking up slag and removing ash, ensuring even gas distribution, supporting the bed layer, and disturbing it). As for the ash melting point, there’s no need to elaborate; in the early stages of a project, the technology is determined based on the quality of coal, while later on, the quality of coal is chosen according to the available technology, as long as they match well enough.

A high temperature of the gasifying agent can reduce oxygen consumption, improve oxygen utilization, enhance the combustion reaction of carbon, increase the yields of raw gas and clean gas, and decrease the calorific value of the raw gas (mainly due to a reduction in methane). There are many factors that affect the temperature of the gasifying agent, such as the steam-to-oxygen ratio, oxygen temperature, the amount of gas generated in the jacket, steam temperature, the amount and temperature of other steam entering the furnace (some plants use additional waste steam for reuse in the furnace), and so on. Generally speaking, a higher temperature of the gasifying agent is advantageous; if it is too low, gas production is reduced, oxygen utilization efficiency drops, severe corrosion occurs in the furnace grates and the lower part of the gasifier, and there are issues such as leakage at the ash lock flanges and the gasifying agent