Process parameters

(1) Clinker production: ≥ 1000 t/d ； (2) Heat consumption during clinker burning
(3) Comprehensive electricity consumption of clinker
(4) Comprehensive electricity consumption of cement
(5) 28 day strength of clinker
(6) Dust emission concentration

Production method

Cement production mainly uses limestone and clay as raw materials, which are crushed and proportioned into raw materials, and then fed into a cement rotary kiln to calcine mature materials. The clinker is then added with an appropriate amount of gypsum, mixed with some mixing materials or additives, ground into cement through cement grinding, and transported out of the factory by packaging machines or bulk machines. The dry cement production process commonly used in cement production equipment. The method of simultaneously drying and grinding raw materials into raw material powder, and feeding them into a dry rotary kiln for calcination into clinker. The main advantage of dry production is low heat consumption.

Process description

5.1 Limestone and Sandstone Crushing
Limestone and sandstone are crushed by their respective crushers, and two crushers are located on the factory site
5.2 Limestone multi storage combination
The crushed limestone is transported by a belt conveyor to the entrance of the bucket elevator, then transported to multiple warehouses, unloaded from multiple warehouses, and finally transported to one or multiple warehouses. And it is transported by a belt conveyor to the raw material grinding feed bin
5.3 Storage and Handling of Sandstone (Iron Ore)
The crushed sand and gravel are transported by a belt conveyor to the entrance of the bucket elevator, then transported to the sand and gravel storage warehouse, and finally discharged from the bottom of the warehouse. They are then transported by a belt conveyor to the raw material grinding feed bin
5.4 Storage and Handling of Clay
During the dry season, clay is transported by truck from clay mines to clay storage sites and piled up by bulldozers or loaders. The clay from the storage yard is taken out by a loader and fed into a hopper, which is then transported by a belt conveyor to the raw material grinding feed bin. The clay silo is equipped with a movable bottom to prevent the raw materials from accumulating during unloading to the quantitative feeder
5.5 Raw material grinding and conveying
The raw materials are extracted from their respective feeding bins (clay is a plate feeder) by a belt quantitative feeder, and transported to the raw material grinding system by a belt conveyor. Raw material grinding is a circular flow air swept ball mill
Raw materials and finished products are transported into the batching warehouse through air chutes and bucket elevators The hot air from the preheater is used as the drying heat source for the raw material mill. When the rotary kiln stops or the hot air in the preheater is insufficient, there is also a backup oil furnace
5.6 Raw material homogenization and feeding into preheater
The raw materials in the ingredient warehouse are homogenized to achieve the standard of ideal finished product density. The homogenized raw materials from the ingredient warehouse are fed into the preheater through the kiln feeding system, which consists of a level box, flow valve, weighing scale, air conveying chute, bucket elevator, etc
5.7 Clinker calcination
Raw materials are heated and pre decomposed in a 5-stage preheater/decomposition furnace, and 90-95% decomposed before entering the rotary kiln. The hot clinker from the kiln is cooled in a third-generation clinker cooler. The cold clinker from the cooling machine is transported to the clinker storage (2 pieces) by a bucket elevator Part of the exhaust gas from the clinker cooler is used as a heat source for coal/peat mills. Part of the exhaust gas from the grate cooler enters the kiln as secondary air, while another part enters the decomposition furnace as tertiary air. The rest is removed from dust in a bag filter with an air-to-air heat exchanger and discharged into the atmosphere. The dust collected by the bag filter is sent to the clinker silo
5.8 Kiln/Raw Material Grinding Waste Gas Treatment
Part of the exhaust gas from the kiln preheater outlet is used as a heat source for the raw material grinding system. The remaining waste gas from the raw material mill is discharged into the atmosphere after passing through a bag filter with an air-to-air heat exchanger for dust removal The dust collected by the bag filter is sent to the homogenization warehouse or clinker warehouse
5.9 Natural Gas Fuel System
The fuel feeding system extraction point is equipped with flow gates and valves, measuring instruments and meters, and is pneumatically transmitted to the main burner and decomposition furnace burner
5.10 Storage and Handling of Clinker
Set up two clinker warehouses to store clinker
5.11 Storage, crushing, and treatment of gypsum and volcanic rocks
After arriving at the factory, volcanic rocks are broken, dried, and stacked in covered warehouses, and gypsum is also broken and stored. Gypsum and volcanic ash from the warehouse are both fed by loaders and transported to their respective feeding bins by belt conveyors. Each feeding bin has two extraction points, which means each cement mill is equipped with a feeding bin
5.12 Cement Grinding
Clinker, volcanic ash, and gypsum are proportioned by a belt scale according to the set values, and then the mixture is sent to a circulating water mud mill by a belt conveyor. The finished products are transported to the cement silo by an air chute and a bucket elevator. The exhaust gas from the grinding process is discharged into the atmosphere after being dedusted by a bag filter
5.13 Cement Storage and Shipping
Cement is stored in four circular warehouses. The library has a conical bottom (not a flat bottom) and is equipped with inflatable pads to ensure consistent extraction ratios The outgoing cement is transported to the cement packaging station through an air conveying chute and a bucket elevator. Provide a bulk ash water ratio expansion tank and dust collector, but only feed from one warehouse The packaging station consists of a rotary 8-nozzle packaging machine system with a production capacity of 100 tons/hour. Bagged cement is loaded onto trucks or delivered to finished product warehouses through belt conveyors
5.14 Compressed Air Station
Compressed air is mainly used in bag filters, gas control valves, preheater areas, and pneumatic instruments. The total compressed air demand is 40m3/min, with a pressure of 0.5~0.7MPa. The station consists of 4 sets of air compressors and supporting drying/dust collection equipment; 3 sets for use and 1 set for backup. Each compressor has a capacity of 15m3/min and an exhaust pressure of 0.75MPa. Compressed air indicators: temperature<40 ° C, dust particle size<1 μ m, oil 0.01ppm, and pressure (air) dew point 2-10 ° C The compressed air from the station is distributed to the workshop through a buffer tank, pressure gauge, and control valve.

Technical Parameter