Cement Production Process
Cement rotary kiln production line is mainly used to calcine cement clinker, so it is usually called cement clinker rotary kiln production line. The cement rotary kiln production line designed and developed by Shenghui equipment group includes: dry process cement rotary kiln production line, semi dry process cement rotary kiln production line and wet cement rotary kiln production line. Shenghui equipment group has developed a series of large-scale new dry process cement rotary kiln production line by using domestic advanced technology. It has the first-class domestic cement rotary kiln Development Research and design team, perfect cement rotary kiln test and detection means, and excellent large-scale cement rotary kiln manufacturing equipment and manufacturing technology. It has formed a perfect cement rotary kiln design, manufacturing, installation and commissioning Service as one of the technology and production system.
Main process flow and host configuration
Limestone crushing, conveying and storage. One mb56 / 75 crusher (outdoor layout) is used for limestone crushing. When the size of the crusher is less than or equal to 500mm, the maximum capacity of the crusher is from 500mm to 1500mm t) In the process of pre homogenization and storage, the stacker (stacking capacity: 800t / h) cantilever, loop line continuous distribution, reclaimer (reclaiming capacity: 500t / h) bridge type, end face reclaiming and center discharging. The homogenized limestone is sent to raw material batching station by belt conveyor.
Auxiliary raw material storage, crushing and transportation. The auxiliary raw materials sandstone and iron ore are transported into the plant by truck and unloaded to the open storage yard for storage. Among them, the sandstone open-pit storage yard is 60 m × 20 m with a reserve of 5100 T; the iron ore open-pit storage yard is 32 m × 20 m with a reserve of 2730 t. One pc1609 hammer crusher is used for sandstone and iron ore. the crushing capacity is 50-70t / h when the feed particle size is ≤ 600mm and the discharge particle size is ≤ 25mm. The crushed sandstone and iron ore are transported to the raw material batching station by belt conveyor and stored in their respective batching warehouses. The fly ash is transported to the raw material storage station by the auto unloading system.
Raw material batching station. The raw material batching station is equipped with limestone, sandstone, iron ore, fly ash four batching storehouses (the specifications are all φ 12 m × 25 m, and the reserves are respectively 220016002200770t). The weighing feeder is set at the bottom of the silo, and various materials are quantitatively given according to the set ratio. Raw materials are sent to vertical mill system by belt conveyor for grinding.
Raw material grinding and waste gas treatment. MLS3626 vertical mill (outdoor layout) is used for raw material grinding, and the drying heat source is the waste gas from preheater. When the particle size of the feed material is 90% ≤ 75mm, the fineness of the product is 80 μ m, the sieve residue of the square hole sieve is less than 12%, the moisture content of the feed material is less than 8%, and the moisture content of the raw material is less than 1%, the production capacity of the system is 185t / h (after abrasion). After being separated by fine powder separator, the raw material from the mill is mixed with the dust collected by the humidification tower and the electric dust collector, and then sent to the raw material homogenization silo for homogenization and storage through the chute and bucket elevator; the waste gas from the mill is purified by the electric dust collector and discharged into the atmosphere.
Raw material homogenization silo and raw material into kiln. The qualified raw material from the mill will enter the Φ 18m × 50m CP type (effective reserve is 9000t) raw meal homogenization silo through the raw material distributor on the top of the silo for homogenization, and then the raw material will be quantitatively discharged into the kiln system through the unloading device. The raw material feeding system is equipped with a load bin, and the metering and flow control equipment are set under the bin. The raw material measured is fed into the kiln tail preheater system by bucket elevator and other equipment.
Clinker burning system and storage. The clinker burning system is composed of low pressure loss single series on-line five stage preheater and calciner (RF5 / 2500 type, the decomposition rate is more than 90%), Φ 4.0 × 60m, lbt32216 new type control flow grate cooler, all of which are NCDRI technology. Among them: (1) after being cooled by grate cooler, the clinker discharged from the kiln is sent to 2 - φ 18 × 40m circular silo (effective reserve of 2-10000t) by chain bucket conveyor and disc conveyor, and the outbound clinker is sent to cement clinker outward transportation and cement batching station through discharging device and belt conveyor; ② high temperature gas at hot end of cooler is introduced into calciner as combustion gas of calciner through tertiary air duct, with medium temperature Part of the hot gas at the end is introduced into the coal mill as the drying heat source of raw coal; the exhaust gas from the tail end is purified by the electric dust collector and discharged into the atmosphere through the chimney, and the dust concentration of the discharged gas (converted into standard condition) is less than 100mg / m3.
Raw coal storage and transportation, coal preparation and transportation. The raw coal transported into the plant by truck is stored and pre homogenized in a 21m × 113m crane garage (with a reserve of 9300t). There are two raw coal bunkers in the hanging garage. On the one hand, it is considered to shorten the traveling distance of the crane, on the other hand, the matching of two kinds of coal with different quality is considered. The weighing feeder is set at the bottom of the bin, and the coal is sent to the coal mill by the belt conveyor after measurement for grinding. A mpf1713 roller disc pulverizer is used for pulverized coal preparation, which is arranged in the open air. When the water content in the mill is less than 10%, the moisture content of pulverized coal is less than 1%; the particle size of raw coal is ≤ 50 mm, the fineness of pulverized coal is 80 μ m, and the residue of square hole screen is 11%, the system output is 20t / h. The pulverized coal from the mill enters the separator along with the air flow for separation. The finished pulverized coal is carried into the air box pulse bag filter for collection and then sent to two pulverized coal silos for storage by screw conveyor. The waste gas is discharged into the atmosphere after purification. The pulverized coal metering system is set at the bottom of the pulverized coal bunker, and the pulverized coal is sent to the kiln head and the calciner for combustion after being measured by the metering system.
Slag drying and transportation, gypsum crushing and transportation. The slag as admixture is transported into the plant by truck and discharged into the open storage yard for storage. The slag is sent to the bucket elevator by the forklift truck, and then sent to the dryer with a diameter of 2.4 × 18.350m by the bucket elevator for drying. The drying capacity is ≥ 30t / h (the initial moisture content of the material is 20% and the final moisture content is 1.5%). The gypsum is transported into the plant by truck, unloaded to the open storage yard with a storage capacity of 4000t, and then fed into pfc-1609 impact hammer crusher (the production capacity is 50-70t / h when the feed particle size is ≤ 600mm and the discharge particle size is ≤ 25mm) by the heavy plate feeder. The crushed gypsum is transported to the gypsum batching bin by bucket elevator and belt conveyor for storage.
Cement grinding, transportation and storage. The cement batching station is equipped with clinker, gypsum, limestone and slag batching silos, of which the clinker silo is φ 10 m × 22 m with a reserve of 2000 t; the gypsum silo, slag silo and limestone are all φ 8 m × 22 m with reserves of 800, 400 and 900 t respectively. There are weighing feeders at the bottom of each storehouse, which can give quantitative information of various materials according to the set ratio. Besides, bulk clinker facilities are set at the side of clinker batching warehouse for external use of clinker. After the four materials are discharged in proportion by the feeding metering equipment, they are sent to two sets of loop flow cement grinding systems composed of Φ 3.8 × 13m ball mill and high efficiency powder concentrator for grinding. When the specific surface area of cement is 3200-3400cm2 / g, the production capacity of single system is 75t / h; the grinding materials are sent to the high-efficiency separator by bucket elevator for separation, and the coarse powder is grinded again, The finished cement products are collected by the air box pulse bag filter, and then sent to eight φ 15 m × 34 m cement silos (the single storage capacity is 5300 T) by air conveying chute and bucket elevator. The waste gas from cement grinding system enters into the high efficiency gas box pulse bag filter for purification and then discharges into the atmosphere. After the cement is discharged from the unloading device at the bottom of the silo, it is sent to the cement packaging workshop and bulk cement bin by belt conveyor, bucket elevator and air conveying chute. Two sets of eight mouth rotary packers are used for cement packaging, and the capacity of each packer is 90t / h. The packaged bagged cement is sent to the 84m × 30m bagged cement product warehouse for storage (the reserve is 6000t) through the bag unloading and conveying system, and can also be directly loaded and shipped. There are two cement truck bulk facilities under the cement bulk bin for truck bulk use.