Operation Of Parallel Flow Asphalt Mixing Plant - Atlas Industries

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Plot No.14/1, GIDC-II, Dediyasan Mehsana,
Gujarat INDIA contact_at_atlasindustries.in
91-2762-224065
www.atlasindustries.in
Asphalt Batch Plant VS Drum Mix Plant
A hot mix plant is a combination of several
components both electrical and mechanical
working in sync to make a product which we call
as HMA (Hot mix asphalt). The combination of
these components allow cold aggregates to heat
and then mix the same with liquid bitumen and
minerals in varying proportions to produce
asphalt mix as per requirements. These plants can
be categorized as stationary and portable. Hot
mix asphalt plants can also be categorized as
continuous type and batch type. Continuous
plants produce asphalt mixture in continuous
operation and batch type plants produce HMA in
batch. The two basic types of asphalt plants
used in the process of making hot mix asphalt are
asphalt drum mix plants and batch plants. Batch
plants vs Drum plants Asphalt batch plants will
make hot mix asphalt in fixed batches. One by one
batches are continuously made to make hot mix
asphalt. Some of the advantages of asphalt batch
plant are It offers best quality of hot mix
asphalt. The flexibility offered is best. It is
possible to edit batch sizes and mix material
designs frequently. The control systems are very
advanced allowing user to have multiple options.
The level of pollution control is better than a
drum mixer. Some of the advantages of continuous
drum mixers are The initial cost is low
compared to batch plant. The land required to set
up is less compared to batch plant. The process
here is continuous. Meaning uninterrupted
production is there. It is easy to have a higher
capacity machine without exponentially increase
in its price.
The functioning of both the plants is different
but the main purpose is to make hot mix asphalt
as per the requirement.
Counter flow asphalt plant is also a continuous
plant but featuring a different technology
compared to the traditional drum plant. In
counter flow plant, the flow of aggregate and
flame direction is opposite. Dust suction is done
at the point where the aggregates enter the
drum. Here is what we are going to mention in
the article below Common operations and
components to both the batch and drum type.
Operation of parallel flow asphalt mixing
plant. Process of counter flow asphalt mixer.
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Plot No.14/1, GIDC-II, Dediyasan Mehsana,
Gujarat INDIA contact_at_atlasindustries.in
91-2762-224065
www.atlasindustries.in

• There are certain common operations common to both
  the types and the components are also similar.
  They are as below
• Component Aggregate feeder
• Operation Cold aggregate storage and feeding
• Component Drum and burner
• Operation Drying and mixing (parallel flow)
  Drying of aggregates (Batch type)
• Component Fuel tank for dryer burner
• Operation Storage and supply of fuel to the
  burner.
• Component Primary scalping screen and charging
  conveyor
• Operation Removal of oversized material before
  the aggregates enter the drum.
• Operation of parallel flow asphalt mixing plant
• The operation of parallelflow type of asphalt
  mixing plant is a continuous process where the
  ingredients are added by proportions to the cold
  feed bins. The feeder bins store the cold
  aggregates in separate bins and transfer the same
  to the drying drum. The main difference between
  this process and the batch plants starts
  here.Aggregates are introduced to the burner end
  of the drum and the flow of aggregates and the
  burner flame is parallel to each other and hence
  the name parallel flow asphalt mixing plant.

Process of counter flow asphalt mixer The
process of counter flow plant is similar to the
parallel flow plant and is a continuous process.
Here also the entry and quantity of bitumen and
minerals is controlled by the flow of aggregates
just like the parallel flow plant. The main
differentiating factor lies in the flow of
aggregates compared to the burner flame position
which is opposite and hence the name counter
flow. Even the flow of exhaust gases is from the
point where aggregates enter the drum. The
addition of bitumen, RAP and minerals is behind
the burner flame.
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Plot No.14/1, GIDC-II, Dediyasan Mehsana,
Gujarat INDIA contact_at_atlasindustries.in
91-2762-224065
www.atlasindustries.in
Working of Asphalt Batch Mix Plants This
asphalt batch mix plants features the most
advance technology. It is best for getting
quality HMA. The process-working starts when cold
aggregates are fed to the appropriate aggregate
feeder bins. They then are metered from the
hoppers individually and move towards the drying
drum. In between they have to pass though a
primary scalping screen for removal of oversized
materials. A conveyor takes the cold aggregates
collectively into the drying drum.
Dust collection is done at the entry point of the
aggregates and treated by a primary and
secondary dust collector. Here the primary dust
collector is cyclone type and the secondary dust
collector can be wet scrubber or a bag
house. The screens are inclined horizontally and
are of different sieve sizes depending on the
mix material requirement. Once the aggregates
pass thought the vibrating screen, they are
separated and placed in different bins just below
the vibrating screen. This separation is
according to the size of the aggregates. This
screen has provision for removal of oversize and
overflow material. In certain asphalt batch
plants, there is a separate bin which stores RAP
material. The aggregates are stored in the bins
separately and the bins open as per the batch
which is set. Here the quantity of each size of
aggregates can be controlled as per requirement.
At the same time, the bitumen which is stored in
the bitumen tanks is flowed from the tanks below
by an asphalt pump into a bucket near the mixer.
This bucket weighs the bitumen and then pumps
the same into the mixer. Before the entry of the
bitumen into the mixer, hot aggregates (and RAP)
have already entered the mixing unit. The
material already in the mixing unit is as per
the desired ratio. The mixing time of the twin
shaft mixer can be set as per requirement. After
mixing, the HMA is discharged into a storage
silo or into waiting trucks below which takes
them to the job sites. You are going to make a
long term investment. It is important that you
understand your primary requirement and then
select a product accordingly. There are many
companies offering drum and asphalt batching
plant for sale. Before buying an equipment it is
important to check all asphalt plant parts and
ensure that it meets or exceeds your
requirement. It is equally important that the
equipment that you are buying is easy to use,
maintain, transport and is easy on the pocket.
This is one investment which can yield a lot of
money, if taken care.