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1. The generation mechanism of mixed generator gas. The gas referred to in this article is different from what people usually call coal gas. The gas that people usually refer to refers to liquefied petroleum gas, and the gas referred to in this article is the gas converted into anthracite by using a gas generator. The gas is cooled, washed, dusted, decoked and desulfurized, and then sent to the kiln for combustion using a gas pressurized fan. The most basic chemical reaction is C+H2O=CO+H2, that is, under high temperature conditions, hot carbon reacts with water vapor to produce carbon monoxide and hydrogen, which is coal gas. The reaction mechanism is the same as that of water gas in nitrogen fertilizer plants, except that the production process of water gas used in nitrogen fertilizer plants is intermittent. That is, a burst of air is first passed into the gas furnace to burn the coal, and then water vapor is passed into the gas furnace to produce water gas, and the cycle repeats. Therefore, nitrogen fertilizer plants generally have two gas generators used alternately or a gas storage cabinet is built. The gas used in ceramic factories now is actually a mixed producer gas, that is, a mixture of water vapor and air is continuously passed into the gas furnace to continuously produce gas, so it is called mixed producer gas. The water gas from the nitrogen fertilizer plant is used as raw material for the production of chemical fertilizers, while the ceramics plant is used as fuel. 2. Possible pollution caused by gas stations and solutions ① During the transportation of coal, dust may be caused to fly. Therefore, closed carriages must be used for transportation and water should be used to wash coal. ② The gas station itself has no waste gas emissions and therefore does not cause pollution to the atmosphere. However, sulfur dioxide will be emitted when gas is burned. To solve this problem, a desulfurization tower must be installed at the gas station and low-sulfur coal must be used. ③The waste residue generated by the gas station, that is, coal slag, will not cause pollution to the environment. The coal slag generated by the gas station can be used to produce cement or improve the soil. For details, see the book "Fly Ash Utilization Technology" written by Han Huaiqiang and Jiang Tingda. ④Water used in the gas station's double standpipes and scrubbers is recycled and not discharged. Due to continuous evaporation, water needs to be replenished in the circulating pool regularly, so the gas station will not cause water pollution. 3. Cost comparison between burning gas and burning diesel in ceramic factories. The average price of diesel in the past two years is about 2,400 yuan/ton. Two tons of anthracite can replace one ton of diesel for every gasification. The factory price of each ton of anthracite is 600 yuan, and gasifying two tons of anthracite requires 120 yuan for electricity, 30 yuan for labor, 10 yuan for water, and 40 yuan for depreciation. Based on the above, the cost of replacing 1 ton of diesel with gas is 600×2+120+30+10+40=1,400 yuan. Burning gas can save 1,000 yuan per ton in fuel costs compared to burning diesel. A ceramics factory that consumes 30 tons of diesel every day can save 30,000 yuan in fuel costs every day after switching to gas. The investment in a gas station is about 3 million yuan (including infrastructure), and the investment payback period is about 100 days. From the above comparison, we can know that burning gas is more economical than burning diesel. Therefore, more than 90% of ceramic factories in Zibo, Shandong have switched to burning gas. 4. The influence of burning gas on the quality of ceramic products Cold gas is a clean gas fuel, suitable for burning colored glazed bricks, porcelain tiles, vitrified tiles, colored glazed mosaics and crystal tiles. Compared with burning diesel, the glaze quality of the product has been improved, but black core is easy to appear when the control is not good, so it is not suitable for burning permeated polished tiles. The maximum firing temperature of coal gas can reach 1280°C. The amount of flue gas when burning coal gas is about 30% greater than that when burning diesel. The kiln exhaust fan needs to be appropriately enlarged. Burning gas has little impact on kiln output.