Counter flow asphalt mixer manufacture
Asphalt mixer which is counter flow type is an equipment which is between the batch and drum plants. They are known to be more efficient for drying of virgin aggregates. Atlas manufactures these mixers in three options: double drum (one drum for heating and one drum for mixing), single drum with pug mill (twin shaft unit) (drum for heating and continuous pug mill unit for mixing) and single drum type (first half for heating and second half for mixing). This equipment is designed to produce high quality hot mix asphalt (HMA). The high efficiency, low fuel consumption of this equipment coupled with better heating and mixing quality has done wonders. The separate zones for drying and mixing help achieve maximum level of heat transfer and fuel efficiency.
The first drum here does the heating of the aggregates where as the second drum (or in some cases we also supply a mixer instead of drum) allows mixing. In plants with single drum, the first half is for heating and second half (behind the burner flame) is for mixing. The first drum as well as the second drum / mixing unit are tilted and rotating so that aggregates and mixed material can move freely from one end to the other. Virgin aggregates enter the top part of the first drum and move towards the other part. The other end is where the burner is located. This means that the aggregates are moving towards the heat source. This helps in removing the aggregate moisture more effectively. This is one of the reasons that make a counter-flow asphalt drum plant better than the traditional asphalt drum mix plant. The mixing takes place in a separate drum / mixer or just behind the burner flame.
This plant is the answer to asphalt recycling for drum mixers. Recycled asphalt can be introduced in the second drum / second half of the mixing unit. In the single drum plant, RAP collar is provided for addition of recycled asphalt into the mix. The RAP (Recycle Asphalt Pavement) system here consists of a feeding unit equipped with belt conveyor system with variable speed drive motor for addition of RAP into the mixing zone. RAP is nowhere in contact with the burner flame. This is important because we do not want to overheat the RAP and burn it.
Plants are available in stationary as well as portable design. The suction of hot gases is at the entry point of the drying drum making it environmental friendly compared to drum mix plant. Plant is available in capacities 40 tph to 120 tph, higher capacities available on request. Plants are designed for easy maintenance and are durable.
Cold feeder bins:
Cold feeder bins are for storage of cold aggregates and each bin comes with variable speed drive motor to regulate the flow individually.
Scalping screen and charging belt:
Primary vibrator screen keeps the larger particles out and charging belt passes the aggregates to the drying drum.
Drying drum / drying zone:
Drying / heating zone of counterflow asphalt mixing plant is equipped with unique flights that help in full utilization of the burner heat thus allowing the aggregates to get dried faster and also helps to save a lot of fuel.
Low noise modulating burner works very efficiently for this equipment. It allows fast heating of aggregates in short time and also saving a lot of fuel.
Mixing drum / mixer / mixing zone:
For mixing of hot aggregates there are two options available: drum or pug mill mixer. Drum mixer can be separate and behind the drying drum or drum mixing can be done in the same drum but behind the burner flame (in a single drum plant). Pug mill mixers are also popular as they offer rapid mixing in a continuous process. Separate mixing or mixing behind the burner means better quality of hot mix asphalt. Recycle asphalt entry is into the mixing zone away from the burner flame.
Bitumen tanks are available in different capacities and with direct or indirect heating system.
Fuel tank for dryer burner:
Stores and supplies the fuel required for dryer burner.
Atlas is manufacturer of Asphalt Drum Mix Plant which provides the machine with filler unit for addition of filler in the mixing unit.
Pollution control units:
Dry and wet dust collectors are efficient pollution control units. Bag filer can also be used in place of wet dust collector.
Easy to use software and maintenance free control panel is the key feature of this equipment. It is housed inside a cabin.
Storage silos of various capacities are available.