The production source of this aggregate production system is pit river pebbles. According to the characteristics of the raw materials, the process design is that the raw materials are pre-screened and then crushed in three stages.
Pre-screening <300mm raw materials have a large mud content, use a vibrating screen to wash, remove mud and natural sand.
The coarse crushing area is open-circuit production. A jaw crusher produces semi-finished materials with a particle size of ≤300mm.
The secondary crushing and the tertiary crushing belong to the medium and fine crushing area, and are dry closed-circuit production. The secondary crushing is equipped with two coarse crushing cone crushers, which are used to crush the intermediate and fine crushing materials. Three-stage crushing uses two fine crushing cone crushers to process the coarsely crushed aggregate, and the produced aggregate particle size is 0-31.5mm. In addition, dust removal equipment is required for secondary and tertiary crushing.
The plastic sand making area is dry flexible production, and a dust removal and powder selection system is designed to adjust the powder content in the manufactured sand and the proportion of the remaining 4 aggregates.
The process is smooth, simple and highly reliable. The finished aggregates at all levels can be adjusted according to market needs, and the output and quality of the finished products are fully guaranteed.
Coarse crushing process
The designed processing capacity of the coarse crushing area is 1500t/h, and the pebbles of the foundation pit are transported to the raw material warehouse and the grate silo for processing by dumping and trucking.
Aggregate larger than 300mm enters the jaw crusher for crushing, equipped with a F5X1045 vibrating feeder and a PEW760 jaw crusher. The initial discharge port is 150mm, the discharge size is about 0-260mm, and the processing capacity is about 250t. /h.
The aggregates smaller than 300mm enter the mud screening workshop and pass through two S5X3075-3T circular vibrating screens. After desilting and the aggregate crushed by the jaw crusher, they enter the semi-finished product storage yard.
The raw material bin adopts the grate silo, the grate is light rail steel, the spacing is 300 mm, and the silo size is 9 m*6 m, which can meet the requirements of three vehicles to discharge at the same time.
The gravel sewage treatment system consists of sewage collection, fine sand recovery system, vertical flow sedimentation tank, sludge dewatering and clean water recovery systems.
The clean water is sprayed on the vibrating screen by the clean water circulation pump for stone cleaning, and then the sewage enters the XS300 sand washing machine with the 0-5 mm sand to separate the sand and the sand is sent to the sand bin through the dewatering screen into the belt conveyor.
After the fine sand recovery device, the low-concentration sewage enters the φ12m vertical flow integrated sedimentation tank by the slurry pump 150ZJ, and at the same time uses the metering pump 2JDM-S4000 to dosing PAM flocculant into the vertical flow integrated sedimentation tank through the pipeline mixer to mix the sewage The flocculation reaction occurs, and the clear water floats through the sawtooth weir and flows to the clear pool for recycling.
The concentrated sediment concentration of the silt reaches more than 50% and is discharged to the mud pool.
The mud is lifted by the filter press slurry pump 80ZJ to the chamber filter press XMZ500/1500 for dewatering, the mud cake is transported to the storage yard and stacked, and the clean water from the press filter is recycled into the clean water tank for recycling.
Stockyard for medium and fine crushed semi-finished products (transit silo)
The addition of a transfer stack between the jaw crusher and the cone crusher can ensure that the cone crusher feeds uniformly and produces full load. At the same time, the machine can be segmented during short-term maintenance before and after the transfer stack to reduce machine downtime. Due to the large material here, in order to prevent the transfer stack from blocking the material, a vibrating feeder can be added under the transfer stack to ensure uniform and smooth feeding.
The semi-finished product yard adopts a stacker for single-point stacking, with a stacking height of 16m and a total volume of 11,000 tons. The silo is equipped with a discharge pipe gallery, in which there are 3 ZSW200x120 vibrating feeders and a B1200mm belt conveyor to feed the medium crushing area.
The production line has two yard-type buffer warehouses, each with a capacity of 10000-11000t, which can meet 7-8 hours of segmented production. Each of the two buffer warehouses is equipped with a corridor, and each corridor is equipped with 3 vibrating feeders, using frequency conversion speed regulation; it can better control the flow.
Medium and fine crushing process
The design processing capacity of the medium and fine crushing area is 1000t/h, and two single-cylinder hydraulic cone crushers HST250 (S1) are selected for the secondary crushing. The processing capacity of a single cone crusher is 605t/h. For the third-stage crushing, two single-cylinder hydraulic cone crushers HST315 (H2) are selected. The processing capacity of a single cone crusher is 505t/h, the crushing ratio is set to 9.5, and the material of 0-300mm in the transfer bin is crushed to 0-31.5. mm finished product.
For reasonable and efficient use, it is designed as a group of two units with a centralized layout. The return material larger than 31.5 mm is also returned to the steel structure buffer silo above the three-crushing cone, forming a closed loop system, which is efficient and reduces belt conveyors and steel. The number of structures, while reducing equipment and plant land, reducing initial investment costs.
Check that the processing capacity of the screening area is 1500t/h, and 2 sets of S5X3075-2T circular vibrating screens are equipped with 50 mm and 32 mm screens. After sieving and grading, the stone material ≥31.5 mm is returned. The 0-31.5 mm stone is transported to the transfer warehouse of the vertical shaft impact crusher by the belt conveyor.
Four cone crushers, two in a group, divided into two B1200 belt conveyors into two S5X3075-2T vibrating screens, the processing capacity of a single vibrating screen is 180-1800t/h, and one finished product is screened out (0-31.5 mm). The material is conveyed to the buffer bin of the vertical shaft impact crusher via a belt conveyor for the production of machine-made sand.
The sand-making area has a processing capacity of 1500t/h, equipped with 3 VSI6X1263 vertical shaft impact crushers with a processing capacity of 500t/h. After the 0-31.5mm semi-finished product is passed, shaped and powdered, qualified machine-made sand and fine crushed stone will be formed.
The 0-31.5 mm material produced by the cone crusher cannot be used directly as manufactured sand and high-standard aggregate, and needs to be further shaped by the sand making machine. In order to ensure that the manufactured sand meets the national secondary aggregate standard, the fine powder adjustment function is set in the screening link, which can be adjusted according to the crushing characteristics of the material, and the FMSIII-300.01 winnowing room with blower and dust collector is installed, which can be effectively stripped. And extract the powder content in the machine-made sand to make it fully up to the standard.
Three VSI6X1263 centrifugal crushers are used for shaping sand, and the capacity of a single impact crusher is 545-583t/h. The crushed products enter 6 sets of S5X3072-2 vibrating screens for screening to produce 0-5 mm high-quality manufactured sand and 5-10-20-25-31.5 mm high-quality aggregates.
Finished product screening
The finished product screening area has a processing capacity of 2100t/h, 6 sets of S5X3072-2 vibrating screening building, the upper vibrating screen is equipped with 25 mm, 20 mm screens, the lower vibrating screen is equipped with 10 mm, 5 mm screens, of which 0-5 mm lower vibrating screen Design 3 sets of FMSIII300.01 winnowing room for powder sorting; after winnowing, 0-5 mm machine-made sand and 5-10-20-25-31.5 mm finished materials are conveyed to the finished product warehouse by belt conveyor.
According to the layout characteristics of the on-site production line, the cone crusher and vibrating screen equipment are separated into two workshops to be used as bag dust collectors. The dust collector is arranged in the workshop. The main air duct is arranged between the cone crusher and the vibrating screen, and the top of the vibrating screen is sealed. The blanking points of the cone crusher and vibrating screen are sealed. The dust-containing gas generated at each dusting point is collected by the dust hood and collected into the main air duct, and then enters the bag dust removal system. After treatment, the clean gas is discharged by the fan of the dust collector, and the fine powder collected by the dust collector is discharged from the lower cone.