There are generally two types of asphalt plants: continuous asphalt mixing plant and batch type hot mix plant. The former has a slight advantage in price, but the two are basically in line with their respective price-performance ratios. Let’s have a look of their some differences.
Heating and mixing system
Batch type: Aggregate is heated in the drum to remove dust, and then raised to the vibrating screen. The temperature is easy to control. After reaching the required temperature, it is sieved and stored. The ratio of oil to stone is stable, and the mixing time is precisely controlled by the computer.
Continuous type: Heating, dust removal, mixing and adding asphalt are all carried out in the drum, eliminating the need for a series of links such as lifting, screening, storage, and weighing. However, the temperature control is not precise and the mixing time is difficult to control, which may cause asphalt aging. When the material is broken or unstable, the oil-stone ratio deviation is greater.
Transportation of finished asphalt mixture
Batch type: By increasing the height of the main building, the finished product warehouse and the waste product warehouse are installed under the mixing tank, and the middle is controlled by a pneumatic flap door. After the mixing is completed, the mixing tank door is opened, and the material falls into the warehouse freely. The warehouse body has a heat preservation function.
Continuous type: It is conveyed by belt to an external finished product warehouse a certain distance away. . It takes a long time to transfer to the finished product warehouse and the finished product warehouse has poor thermal insulation performance.
Asphalt heating system
Batch type: The heat conduction oil and asphalt tank are installed separately, connected by process pipeline configuration. The boiler can heat more asphalt tanks by heating the recirculating medium heat conduction oil,therefore the heat utilization rate is high. It is convenient to store a large amount of asphalt.
Continuous type: The heating furnace and the asphalt are integrated, and only one asphalt tank can be heated. The asphalt storage is small, the turnover frequency is high, the fuel heating value utilization rate is low.
Batch type: The burner is an advanced integrated burner and programmable controller. It has high fuel combustion value and saves fuel. It can be automatically or manually ignited according to the situation. The flame size can be adjusted at will. With a built-in blower, it has high utilization rate of heat energy and less smoke emission
Continuous type: The burner of continuous asphalt mixing plant is of low fuel combustion value, high fuel consumption, and a lot of flue gas emissions. It has high failure rate, and external blowers occupy a large space.