What exactly is aggregate? What is the production process? What are the common aggregate production lines?Date: 2019-06-27 Views:
The green development of sand aggregate industry has been concerned by people in the industry. Some studies have shown that sand aggregate has become the second largest consumable of human beings, after fresh water, vertical and horizontal high-speed rail, roads and high-rise buildings, which kind of engineering construction does not need to consume a lot of sand and stone aggregate? So what is aggregate?
What exactly is aggregate?
Aggregate plays a filling and lifting role in concrete, showing loose particles, which improves the durability and stability of concrete.
Divided into natural, artificial and regenerated according to the source;
According to the particle size, it is divided into coarse aggregate and fine aggregate.
According to the density, it is divided into ordinary aggregate and lightweight aggregate.
The fine aggregate between 0.15-4.75mm is commonly known as sand, and the coarse aggregate between 4.75-9.0mm is commonly called stone. Because of natural sand, stone aggregate is gradually drying up, artificial sand making, stone market is hot, all kinds of slag, rock, waste and so on can be processed into the required particle size through mechanical equipment.
Aggregate production process
The selection of aggregate production line is an important part of modern aggregate mine production. The full set of production lines is composed of four systems: feeding system, crushing sand making system, screening system and sorting system.
In this stage, the bulk material in the raw ore of sand and stone aggregate is prebroken by hammering, and the sundries which are not suitable for crushing are sorted out, and the waste wood, plastics and other sundries are removed in order to facilitate the next treatment process. The scrap iron in aggregate is removed by primary magnetic separation.
2. Crushing sand making
Firstly, the primary crushing is carried out on the raw materials by using a first-stage crusher, the vibrating feeder is uniformly fed, and the large aggregate of the sand and stone aggregate is broken to be smaller in size by the movement of the vibrating plate. The coarse-broken material is transported to the transfer pile by the conveying equipment. Then the material can be finely divided by a sand making and shaping machine, and the grain size of the sand and stone aggregate after the sand making machine is processed is uniform.
Third, first stage screening
In this stage, the broken concrete aggregate is screened into the block of 0-40mm and the comminuted material below 5mm by using circular vibrating screen. Among them, the coarse aggregate of 5-40mm can be directly used in the concrete manufacture of general C15-C20. Fine aggregate can be transported to the transfer reactor for the next process.
Fourth, secondary crushing and screening
The secondary grinding can use a ball mill to crush the fine aggregate again. The crushed aggregate is divided into high quality recycled aggregate of 5-20mm, which can be used in the manufacture of C25-C30 concrete. The high quality recycled fine aggregate of 0.15mm-5mm and the fine powder below 0.15mm can be selected by the third stage screening.
Common aggregate production line configuration
Generally speaking, the configuration of aggregate production line needs to be combined with the working conditions of users, current production, finished product particle size, energy consumption and other requirements, and the common equipment combination forms of aggregate production line are as follows:
1, jaw crusher conical crusher sand making machine auxiliary equipment (feeder, conveyor, hoist, etc.);
2. Jaw crusher+reaction crusher+sand making machine+auxiliary equipment;
3. Hammer type crusher + high-efficiency fine crusher + impact type sand making machine + auxiliary equipment.
The aggregate finished product processed by the aggregate production line has the advantages of:
1. The invention has very good particle grading, small stacking void ratio, and can save the cement consumption.
2, with very stable physical, chemical properties, better durability.
3. Less impurities will not affect cement condensation and hardening, and can effectively improve the service life of engineering buildings.
4, the machined aggregate has higher hardness and firmness, and the action of starting frame is more obvious.