Asphalt drum mix plant has relatively high requirements for materials, and the uneven quality of aggregates is not conducive to the application of continuous asphalt plant. The batch mix asphalt plant is better for high-grade road construction.
Cold material system
Batch type: The target mix ratio is used when the cold hopper is discharged, and the speed of the belt drive motor is adjusted by frequency conversion to realize the initial control of the mix ratio. After dust removal and sieving, a computer-controlled electronic scale performs accurate weighing, and finally feeds the materials according to the production mix ratio.
Continuous type: The cold hopper uses the target mix ratio for one-time batching, and the material volume cannot be adjusted. The electromagnetic frequency modulation of the belt-driven motor is used to control the material volume, so that the grading result is rough and the error is large.
Dust removal system
Batch type: Secondary dust removal is carried out with the help of the negative pressure generated by the high-power induced draft fan. The dust collector absorbs a large proportion of dust and flue gas, so that the environmental protection requirements are up to the standard.
After two-stage dust removal, the dust is stored separately, and the size of the dust removal damper can be adjusted. The first stage dust removal is gravity type, and the reclaimed material is returned directly to the heat extraction through the spiral, and finally enters the finished product warehouse without wasting materials.
Continuous type: Most of continuous asphalt plants use water for dust removal, which consumes a lot of water and wastes water resources. The proportion of dust removal is limited. The dust enters the water and can not be reused. It must be cleaned regularly. The degree of automation is low and the workload is increased. Harmful gases are discharged into the atmosphere through water. The pollution is more serious.
Batch mix asphalt plant: There is a very accurate electronic weighing system, including three parts of aggregate, stone powder and asphalt scale. The bitumen measurement is accurate, and it can also be weighed twice, so that the oil-stone ratio can be controlled stably.
Asphalt drum mix plant: There is no necessary weighing and measuring equipment, and the measurement is only completed by the electromagnetic speed regulation of the belt under the cold hopper. The amount of bitumen added is controlled by the time relay to control the bitumen injection time, so as to adjust the flow rate to achieve the goal. The oil-stone ratio is not easy to control.