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Asphalt Drum Mixing Plant Stationary, Cap. 40,60,90,100,120,150,180,200 - details see: https://www.machineto.com/asphalt-drum-mix-plant-stationary-10115064

Asphalt Mixing Plant is used to manufacture coated road stones, which include asphalt, concrete and macadam, collectively known as blacktop. The plants are easy to operate and maintain. Engineered to give excellent performance, these plants are conveniently mobile.

Asphalt Mixing Plant Operation Overview

• In cold feed bins, aggregates are deposited
• The amount flowing in can be monitored by the Control System
• Appropriate amount of asphalt is drawn from the storage tank
• The drum mixer thoroughly blends the asphalt and aggregates
• Excess dust is collected by the dust collection system or Pollution
• Control Unit (Wet Type)
• With the conveyor, HMA is transported to a storage silo or trucks
• The trucks are loaded

Fundamental Components

• Aggregate cold feed bins

• Conveyor and aggregate weighting system

• Drum Mixer

• Dust collection system & wet scrubber

• Hot mix conveyor

• Storage silo

• Control house (cabin)

• Well equipped with Axle Tyre & pneumatic air brake systems with R.T.O. standard

Cold Feed Bins/ Four Bin Feeders

The aggregate components are supplied to the Cold Feed Bins

• An exclusive bin for each component

• Endless belt feeder

• The bins need to be kept full

• Bins get a supply of controlled amounts of each aggregate onto conveyor

• Combination of belt speed and gate controls the material flow

• Accurate moisture content of aggregate is measured and monitored

• The drying time and asphalt supply rate will be dictated to the drum mixer by the moisture content

Benefits

• Maintenance free
• Less power consumption
• Better accuracy

Thermo Drum Unit (Parallel Flow)

Drum Mixer

Parallel Flow Drum Mixing

• Aggregate and air flow in the same direction

• Cold aggregate enters at the same end as the burner

• HMA exists at the opposite end

Inside the Drum Mixer

Thermo drum Unit (Drum Mixer) is equipped with longitudinal troughs or “flights”

The drum is equipped with longitudinal troughs or “flights”

• Lifts the aggregate & drops it in veils through the hot gases

• Time required for the aggregate to dry and heat is determined by drum slope, rotation speed, diameter, length and arrangement & number of flights

• Steel Construction

• Particular rugged

• Resistant to heat and rough usage

• Transmission attained by chain gear & motor

Benefits

• Less wear & tear
• Better heat utilization

Burner

Special Features:

• High pressure jet air burner
• Enclosed type
• The range of burners studied to be used on solid dryers are suitable to meet every need of production
• The burners are enclosed type with construction air counted. The liquid combatable is mechanically atomized at high pressure

Control House (Panel)

Asphalt Mixing Plant operations are controlled and monitored from the control house Computer system controlled

Control Room’s computer system controls and monitors all the Plant Operations

Special Features:

• It has aluminum composite panel sheet and square pipe structure construction, walls and all the coverings are thermally insulated with Rockwool panels with proportionate thickness.
• Flush entrance door with lock and windows and doors are equipped with tinted glass and flush entrance door with lock.
• A central lighting and a driving power complete the equipment
• Control Room with an air conditioner
• Indian standard components & cable
• Soft Starter
• Insulated aluminum panel with large thermal insulation glasses used for construction
• Bent sheet frame for cabin support, gangways with ladder

Benefits:

• Highly durable & no electromagnetic interference

Wet Scrubber

To clean exhaust air or exhaust gas a Wet Scrubber is us used which also removes toxic and pungent compounds. In the fuel gas scrubber, fine water drops in a co-current or counter current flow comes in contact with the gas. Procedure is more effective when the size of water drop is smaller and the total surface area between water or washing fluid and the gas increases. The water or washing fluid is circulated again, normally in order to save water and reduce water wastage.

Operating principle:

Scrubbing liquid is introduced into the scrubber as a spray, which is directed down over a circular "scrubbing vane" arrangement. As the liquid drains through the vanes, it creates curtains of scrubbing liquid. Particle agglomeration initiates as the dust-laden gas enters the scrubber tangentially and collides with the curtains. The coarser particles produced are washed down to the slurry outlet.

The restriction disc located in the scrubbing vane assembly accelerates the spin velocity of the gas. This action causes the formation of fine liquid droplets, which encapsulate the fine particulates when coupled with the flood of atomized liquid from the spray. This enhances the agglomeration again.

The cyclonic action of the saturated gas stream forces the agglomerated particles to fall out of suspension as it spins upward. The coarser droplets impinge on the mist eliminator vanes. Due to this the finer droplets are forced to drop out of suspension by gravitational force and centrifugal force acting on the gas stream as it exits through the top.

The following components can be removed from the exhaust gas:

• • Water soluble substances get dissolved
• • Dust gets precipitated
• • Chemicals that can be hydrolyzed get decomposed
• • Steam gets condensed

Conveyor

Asphalt drum mix plants are computer controlled

Controls are linked to a weigh belt

• The weighbridge weighs the material on the belt.
• Belt weight and Belt speed are input into the computer
• This determines the amount of material per unit of
• It transports the freshly mixed HMA from the drum to the storage silo
• Primary Objectives:
  • o Prevent heat loss
  • o Prevent mix segregation
  • Due to the high mix temperature and the steep incline Drag Slats are used.

Storage Silo (Optional)

• To prevent plant shutdowns due to temporary interruptions of paving or hauling Storage Silos provide temporary storage for HMA
  • Insulated & heated
  • Store HMA 30+ hours
  • Capacity varies (50-350 tons)