The influence of the grate and gas generator structure on operational conditions

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Among the manufacturers that produce and use grills for current gas generation furnaces, when discussing the advantages and quality requirements of such grills, people generally cite points such as \"even air distribution\" and \"strong slag removal and crushing capabilities\". In fact, evaluating each parameter of the furnace grid in isolation in this way is one-sided and inappropriate. This is because the influence of various structural parameters of the grid on its performance is interrelated, and it is also connected to other parameters of the gas generator. The design, manufacture, and selection of grates should be based on a correlation analysis (or matching theory). Next, by analyzing the movement of the carbon layer and ash in the furnace chamber of the gas generator, we will examine the impact of various parameters related to the grate on the distribution of the gasification zone (flame zone) and the stable operation of the gas generator. For spiral conical or fan-shaped grates, the movement of carbon and ash within the furnace can be roughly divided into two processes: ① The carbon and ash in the inner zone of the furnace move diagonally downward under the action of the grate ash pushers (ash discharge ribs), until they reach the ash channel (the circular area above the ash tray that is swept by the ash plow, including the area at the ash discharge port). ②The carbon and ash in the outer ring area of the furnace move downward as the gasification or descent of the underlying support layer (carbon or ash) occurs; upon approaching the ash channel, they fall into it due to gravity, driven by the action of the grate. 1. The height of the part above the furnace grid base. The higher the height, the greater the ash discharge angle of the grate, which enhances the ash discharge effect in process ① and thus weakens process② ； Conversely, as this height decreases, process ① is weakened while process ② is strengthened. 2. The height of the slag discharge rib and the helical angle. If the height and spiral angle of the slag discharge ribs are increased, their ability to discharge ash at an oblique downward direction is enhanced, thereby strengthening process ① while weakening process② ； Conversely, if the height of the slag discharge ribs and the helical angle are reduced, process ① will be weakened while process ② will be strengthened. 3. Air distribution characteristics of the furnace grates. If the porosity and ventilation intensity in the inner ring area of the furnace grid are increased, more ash will be generated in that inner ring area; as a result, process ① is relatively weakened while process is strengthened in terms of the balance between ash generation and removal② ； Conversely, if the porosity of the inner ring area is reduced, process ① will be relatively strengthened while process ② will be weakened. 4. Cross-sectional area and length of the gray channel. The larger the cross-sectional area and the shorter the length of the semi-circular ash channel at the bottom of the furnace chamber, the greater its ability to remove and discharge ash. This enhances process ②, and it is also possible to reduce the rotation speed of the furnace bars, thereby suppressing process ①. Conversely, slender gray pathways will inhibit process ② and enhance process ①. 5. Taper characteristics of the inner diameter of the furnace chamber (jacket). If the inner diameter of the jacket gradually decreases from top to bottom, forming an inverted cone shape, this will weaken process ② while strengthening process① ； Conversely, a jacket with a smaller inner diameter at the top and a larger one at the bottom will enhance process ② while weakening process ①.