Formula for calculating the yield of coking products
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Formulas for calculating the yield of coking products:I. Empirical formula for tar yield: The tar yield depends on the volatile matter content on a dry, ash-free basis (Vdaf%) of the coal fed into the furnace, the degree of coal transformation, and the coking conditions. When the Vdaf% of the coal fed into the furnace is between 20% and 30%, the tar yield (Kx%) can be calculated using the following formula: Kx = –18.36 + 1.53Vdaf – 0.026Vdaf².
II. Empirical formula for crude benzene yield: The yield of crude benzene increases as the carbon-to-hydrogen ratio (C/H) in the coal increases. Additionally, the higher the volatile matter content in the coal, the lower the toluene content in the resulting crude benzene, and vice versa. The yield of crude benzene (KY%) can be calculated using the following formula, within the range of ash-free volatile matter in the coal fed into the furnace as mentioned above: KY = –1.6 + 0.144Vdar – 0.0016(Vdar)². Thirdly, there is an empirical formula for calculating the yield of ammonia: Ammonia originates from the nitrogen present in the coal, and its yield depends on the nitrogen content in that coal. Generally, coal contains about 2% nitrogen; approximately 12–18% of this nitrogen combines with hydrogen at the high temperatures used in coking to form ammonia. The yield of ammonia is usually between 0.25% and 0.35% of the dry coal weight. The empirical formula for the dry-base yield of ammonia (Kd) is as follows: Kd = 17/14 × bNd, % Where: b is the coefficient converting the total nitrogen content in coal to ammonia, typically ranging from 0.12 to 0.18 ； Nd—Dry basis nitrogen content in coal fed into the furnace, % ； 17, 14: The molecular weights of ammonia and nitrogen. IV. Empirical formula for gas production rate: The formula relating the output of coke oven gas (or production rate) y (in standard cubic meters) to the volatiles content (Vd%) of the coal fed into the furnace is: y = 60.0 + 10.0Vd. For example, if the dry-basis volatiles content Vd of the coal fed into the furnace is 28.5%, then y = 345 Nm3 per ton of dry coal.
The empirical formulas for calculating the yields of several coking products provided by you are summarized as follows: 1. Tar yield (Kx%): The yield of tar depends mainly on the volatiles content of the coal fed into the furnace (volatile matter on a dry, ash-free basis, Vdaf): Kx = -18.36 + 1.53 Vdaf – 0.026 Vdaf². 2. Crude benzene yield (KY%): The yield of crude benzene is related primarily to the volatiles content of the coal; the toluene content in crude benzene varies with this volatiles level: KY = -1.6 + 0.144 Vdaf – 0.0016 Vdaf². 3. Ammonia yield (Kd, %): The ammonia yield depends mainly on the nitrogen content in the coal (Nd%) and the conversion factor b (typically ranging from 0.12 to 0.18): Kd = (17/14) × b × Nd. Where: – b is the conversion factor for converting the total nitrogen content in the coal into ammonia (usually 0.12–0.18); – Nd represents the nitrogen content in the coal on a dry basis (%). IV. Coke oven gas yield (y, Nm³/t of dry coal): The relationship between y and the dry-base volatiles content of the coal fed into the furnace (Vd, %) is given by y = 60.0 + 10.0 Vd. The above are empirical formulas for calculating the yields of the main products obtained during the coking process (tar, crude benzene, ammonia, and coke oven gas). .