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The uppermost part of the modern coke oven body is the furnace roof. Below the furnace roof are the combustion chambers and carbonization chambers arranged alternately. The lower part of the furnace body has a regenerator and a ramp area connecting the regenerator and the combustion chamber. The small flue at the bottom of each regenerator is connected to the flue through an exchange switch. The flue is located in the coke oven foundation or on both sides of the foundation, and the end of the flue leads to the chimney. Combustion chamber and carbonization chamber The combustion chamber is where gas is burned, and heat is provided to the carbonization chamber through the partition walls with the carbonization chambers on both sides. The furnace coal is converted into coke through high-temperature carbonization in the carbonization chamber. The wall temperature of the combustion chamber is as high as 1300--1400°C, while the wall temperature of the carbonization chamber is about 1000--1150°C. The temperature of the wall of the carbonization chamber changes drastically when coal is loaded and coke is removed, and the salts in the coal loading are corrosive to the furnace wall. Modern coke ovens use silica bricks to build the carbonization chamber walls. Silica bricks have excellent properties such as high load softening point, good thermal conductivity, strong resistance to acidic slag erosion, good high temperature thermal stability and no residual shrinkage. The silica bricks used to build the carbonization chamber adopt a tongue-and-groove structure to reduce gas leakage and increase the strength of the masonry. ； The brick types used are: T-shaped bricks, wine bottle bricks and pagoda bricks. * * The carbonization chamber walls of coke ovens are mostly made of T-shaped bricks, and after the 1980s, pagoda bricks are mostly used. The wall thickness of the carbonization chamber is generally 90-100mm. * * Mostly 95-105mm. In order to prevent cracks in the coke oven head bricks, the burners of some coke ovens are built with high alumina bricks or clay bricks, and straight joints are provided to relieve stress. * * Coke ovens often adopt this structure. The combustion chamber is divided into many vertical fire channels, and the form of the vertical fire channels varies depending on the type of coke oven. The vertical fire channel consists of two parts: the vertical fire channel body and the top of the vertical fire channel. The gas burns inside the standing fire channel body. The top of the standing fire channel is the part above the roof of the standing fire channel. The distance from the lower surface of the vertical fire channel roof brick to the lower surface of the carbonization chamber roof brick is called the heating level, which is an important dimension in the furnace structure. If this size is too small, the temperature in the furnace top space will be too high, resulting in excessive carbon deposits on the furnace top. ； On the contrary, if the temperature of the furnace top space is too low, the upper part of the coke cake will be insufficiently heated, thus affecting the coke quality. In addition, if the temperature of the furnace top space is too high or too low, it will have a negative impact on the quality of coking chemical products. The main dimensions of the carbonization chamber are length, width, height, taper and center distance. The production capacity of the coke oven increases in proportion to the length and height of the carbonization chamber. The tamping coke oven is different from the top-loading oven in that its taper is smaller, only 0-200mm. Regenerator: In order to recycle and utilize the heat of coke oven combustion exhaust gas to preheat lean gas and air, a regenerator is provided at the lower part of the coke oven body. Modern coke oven regenerators are all transverse regenerators (the center line of which is parallel to the center line of the combustion chamber) to facilitate individual adjustment. There are two types of regenerators: wide regenerators and narrow regenerators. There is one wide regenerator under each carbonization chamber. The narrow regenerator walls are generally built with silica bricks. Some * * Use clay bricks or semi-silica bricks instead of silica bricks to build the lower part of the regenerator where the temperature is lower. Checker bricks are placed in the regenerator to fully recover the heat in the exhaust gas. Checker bricks have to withstand repeated temperature changes of rapid cooling and heating, so they are made of clay or semi-siliceous materials. The checker bricks of modern coke ovens generally adopt special-shaped thin-walled structures to increase the heat storage area and improve heat storage efficiency. There is a small flue at the bottom of the regenerator, which is used to alternately introduce cold gas and air into the regenerator, or to discharge exhaust gas. The alternating rising airflow (preheated gas or air) and downdraft (high-temperature exhaust gas discharged from the combustion chamber) in the small flue have a large temperature difference. In order to withstand the rapid changes in temperature and prevent the gas from corroding the small flue, the small flue needs to be lined with clay bricks. The chute area is located in the passage between the combustion chamber and the regenerator. The chute area structures of different types of coke ovens vary greatly. There are a large number of channels (chute, horizontal brick gas channel, vertical brick gas channel, etc.) arranged in the chute area. They are very close to each other, and the pressure difference between the updraft and the downdraft is large, which is prone to air leakage. Therefore, the design of the chute area must be reasonable to ensure that the furnace body is tight. In order to absorb the expansion of the furnace group towards production, expansion joints are left in each brick layer in the chute area. Sliding joints are set between expansion joints to facilitate the free sliding of the brick layers between the expansion joints when heated. The chute area bears the huge weight of the upper part of the coke oven and is in a high temperature zone of 1100-1300°C, so it is also built with silica bricks. The furnace roof is located at the uppermost part of the coke oven body. It is equipped with fire-seeing holes, coal-loading holes and rising pipe holes for leading out raw coal gas from the carbonization chamber. The bottom layer of the furnace roof is the top layer of the carbonization chamber, which is usually built with silica bricks to ensure uniform expansion of the entire carbonization chamber. It is also built with clay bricks. This kind of brick is not easy to break, but is prone to surface cracks. In order to reduce heat dissipation from the furnace top, clay bricks, red bricks and insulating bricks are used above the top cover of the carbonization chamber. The furnace top surface is usually paved with clinker bricks to increase the wear resistance of the furnace top surface. In rainy areas, the stove top surface is sloped to facilitate drainage. The thickness of the furnace top is determined according to the requirements of ensuring the strength of the furnace body and reducing the temperature of the furnace top. The roof of modern coke ovens is generally 1000-1700mm. * * The roof thickness of large coke ovens is 1000-1250mm.