01.Limestone and clay crushing & conveying
The limestone and clay crushing workshop will be located in the plant. The limestone and clay are discharged into the respective hoppers in front of the crusher via self-unloading trucks. Through the apron feeder, the mixed material is fed into a hammer crusher. Then the fine limestone and clay mixture is sent to the limestone and clay preblending storage via belt conveyor.
02.Limestone and clay preblending storage
One set of covered circular preblending storage for limestone & clay having a total capacity of 24,000 ton shall be provided. Limestone & clay preblending will adopt chevron stacking.
03.Material & coal receiving, crushing
The pure limestone, gypsum, additive & Iron ore are discharged into the receiving hoppers in front of the crushers via self-unloading trucks. Through the apron feeders, the pure limestone, gypsum & additive are fed into hammer crusher, while iron ore is sent to the preblending storage via belt conveyor.
04.Auxiliary material & coal pre-blending storage
One common covered longitudinal preblending storage for auxi. material & coal shall be provided.
The preblending storage will adopt side cantilever stacker.
05. Raw material dosing station
There will be three raw material bins in the system: Limestone & clay, pure limestone, sand and Iron ore.
06.Raw material grinding and exhaust gas treatment
A vertical roller mill with an exterior circulating system is adopted, utilizing waste gas out of preheater as the drying heat source. Materials from the dosing station is through triple air lock valve goes into the roller mill. On the mill bed, materials will be ground to fine powder, and then dried by hot air in the mill.
07.Raw meal homogenizing silo and kiln feeding system
Raw meal will be conveyed into one Φ15.0m homogeneous silo by bucket elevator. The silo with effectively storage capacity is 6,000t. This silo has a multifunction of storage, homogeneous and feeding, with advantage of more effective homogeneous, lower power consumption, easy operation and management.
The kiln inlet adopts pre-calcining system with five-stage cyclone pre-heater and calciners with the calcining rate up to 96%. Qualified raw meal from homogeneous silo, after pre-heated and pre-calcined, will come into rotary kiln. Clinker from the grate cooler will be sent to the clinker silo by pan conveyor. Gas from the grate cooler will be sent to the calciner at the kiln inlet as the tertiary gas. A part of waste gas from the grate cooler will be drafted to the coal mill for heat resource, a cyclone separator will be adopted to reduce the content of kiln dust. And the residue, is purified by the bag filter, will be discharged into air. The dust emission of bag filter is less than 50mg/Nm3.
The coal shall be ground finely in a vertical mill. The output of coal mill is 20 tons per hour with a fineness of 10~12% residue on a 90μm sieve.
Coal will be fed to a vertical mill by a weighing feeder. Drying heat source for coal mill will be from clinker cooler.
10.Cement mill feeding system
Each material is discharged from the storage silo by weighing feeder according to the given ratio, and then they will be transported to the cement mill by belt conveyor together.
11.Cement grinding system
Clinker & gypsum & limestone are weighed by respective weighing feeder and fed to the tube mill for fine grinding.
Ground material of cement mill is fed to a high efficiency separator via air slide conveyors and a bucket elevator. Coarse material is returned to the cement mill, and fine material is introduced to bag filter with air.
12.Cement storage silo
The cement will be stored in cement silos . The aeration system will be installed at the silo bottom. The aerated cement will be transported to the cement packing system and bulk loading system through air slide and bucket elevator.
13. Cement packing and bulk loading (Truck)
Two (02) cement packers of 8-spout rotary type shall be equipped. Capacity of each cement packer shall be 90~100t/h, using bag of 50kg type. Bag cement dispatching system for each packer via road way consists of two (02) dispatching routes which are equipped with mobile truck loader for hood truck.
Bulk cement bins are used for bulk cement truck loading. Through the discharging system and the bulk loader, the cement will be dispatched by the truck.