Dry-type sand production line and dry-type sand making process

Abstract

The invention relates to the technical field of dry-type sand making, and discloses a dry-type sand production line. The dry-type sand production line comprises a screening type vibration feeder for screening raw stone materials and a jaw crusher communicating with the screening type vibration feeder; an impact crusher or a cone crusher communicating with the jaw crusher through a belt conveyor isused for crushing the stone materials crushed by the jaw crusher; and subsequently, the quality of sand powder is improved through sand making by crushing, power removing by drying, powder content adjusting and mixed stirring by adding water. The dry-type sand making process comprises the steps of screening the raw stone materials, crushing the raw stone materials for the first time, crushing theraw stone materials for the second time, crushing the raw stone materials for sand making, drying to remove the powder, controlling the sand powder content by humidifying the sand powder and adjusting the powder content after drying and removing powder, adding water for mixing and stirring, and bonding the powder and the sand into a whole to obtain a finished product. According to the productionline and the process, the powder content of sand particles is reduced through multi-stage crushing; and drying instead of water washing is used for powder removal, and the heat of drying for powder removal is recycled, so that energy saving, environment-friendliness as well as high production efficiency are achieved.

Description

technical field [0001] The invention relates to the technical field of dry sand making, in particular to a dry sand making production line and a dry sand making process. Background technique [0002] In order to protect the natural environment and avoid excessive excavation of river channels, the country promotes the use of machine-made sand instead of natural river sand. In order to alleviate the tight supply of sand and gravel materials, the machine-made sand industry and sand-making machinery have been rapidly popularized. However, traditional sand-making machinery and simple sand-making processes are commonly used now, and it is difficult to guarantee the quality of machine-made sand. In building construction, when the quality of machine-made sand is not up to the standard, in order to make the concrete strength up to the standard and pass the inspection, the amount of cement or additives has to be increased. Increasing the amount of cement or additives will not only inc...

AI Technical Summary

Problems solved by technology

[0004] 1. The flaky shape of the finished sand needles produced exceeds the standard, the crushing value is high, the sand volume in the middle section with a particle size of 0.315-1.25 mm is relatively small, the continuous gradation of the machine-made sand is not up to the standard, and the quality of the finished sand is difficult to meet the requirements for concrete sand

[0005] 2. The powder content of the finished sand produced by the existing sand making process generally exceeds the standard, and it needs to be washed to remove the powder

Among them, water washing and depowdering not only need to use a lot of water resources, but also a large amount of sewage sludge needs to be treated during the depowdering process. The sewage sludge treatment requires pumping, adding precipitating agents for precipitation, drying treatment, cleaning and transportation, etc. The investment in equipment is large 1. The daily treatment costs are high. Due to the large amount of sewage, it is difficult for the treated sewage to meet the cleanliness standard. After treatment, the sludge powder containing sedimentation agents has an impact on the environment, and it is difficult to reuse and sludge stacking

[0006] 3. Washing and removing powder will cause the crushed powdery stone to be lost with the water flow, resulting in a waste of more than 20% of raw materials, and the sewage treatment machinery cannot operate stably and effectively for a long time, resulting in a greatly increased production cost

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