Industry Reports
Comparative analysis of gravel production line wet process and dry process
Similarities
(1) This two production processes are similar, and both need to be crushed before screening.
(2) The main production machine of the two are basically the same, that is, coarse crusher, fine crusher, high-efficiency sand making machine and screening machine are the main equipment.
(3) The production purpose of the two is also the same, both are for the production of mechanical sand that meets the requirements of engineering sand.
(4) Regardless of which kind of machined sand process route is adopted, the finished machined sand produced should meet national or industry standards, such as GB / T14684-2011 "Sand for Construction", GB / T14685-2001 "Pebble for Construction, Crushed Stone "and so on.
(5) The construction of green mines promotes the development of environmental protection. Regardless of the mechanism sand process, environmental protection facilities and environmental protection indicators must be considered.
Differences
(1) Different working principles
Wet sand making is a water-washing sand making mode using a sand washer. With the help of hydraulic method to remove powder, a large amount of mud powder content in the sand particles is removed by water washing, so that the powder content of the machine-made sand is low.
The dry sand making method adopts the dust removal box negative pressure dust removal or the powder separator positive pressure dust removal or a combination of the two methods. The wind power is used to remove the powder, and the sand powder is efficiently separated by the wind. Finally, the construction sand with good quality is selected. Dust is also collected as a by-product.
(2) Different occasions
Wet sand production is suitable for watery areas, and is closer to the water source. Wet sand making can establish sedimentation tanks and use filter press equipment to purify sewage to achieve the purpose of zero emissions and recycling of water resources. At the same time, fine sand recovery equipment can also be configured to collect fine sand in sewage. Dry sand making is suitable for areas with severe water shortage, and the equipment can be used to remove powder without consuming a large amount of water.
(3) Different raw materials contain water
The wet sand making process basically has no special requirements for the water content of the raw materials, and the dry sand making process has high requirements for the water content of the raw materials. The smaller the water content of the raw materials, the more beneficial it is to take advantage of the dry sand making process, especially the raw material moisture content is less than 2 %Time.
(4) Different production costs
The wet sand making process consumes a lot of water, 1ton sand and gravel requires about 2-3.5m³. Compared with the wet process, the production cost of dry sand production will be relatively low, but the investment cost is large. Dry sand making uses the wind method to efficiently separate the sand powder. There is no need to add a large amount of water to clean during the production process, and no flocculation treatment of sewage is required.
(5) Different development stages
The dry sand making technology is obviously later than the wet sand making technology, and it is a new technology further developed on the basis of the traditional wet sand making production line. Compared with wet sand making, this dry method does not require a large amount of water in the process of sand powder removal, and mainly uses the effect of wind to remove powder.