Modified Asphalt Contactor Reactor PDF Print E-mail
The STRATCO® Modified Asphalt Contactor™ (MAC) reactor is designed to blend fillers with asphalt cement to produce an economical asphalt roofing adhesive. It also functions as a booster heater to raise the temperature of this material.

The high dispersion mixing in the MAC is achieved using the hydraulic head assembly, in conjunction with the unique internal vessel configuration, forcing the entire contents through multiple blending cycles every minute.

Intense mixing capability enhances quality of products, through homogenous mixture and temperature.

The asphalt-polymer-filler (e.g. limestone) blend is pulled down through the inside of the circulation tube via the impeller.

Turbulence is established between the stationary shear vanes and the blades of the impeller, resulting in a zone of high shear and intense mixing.

As the material passes through the impeller, its velocity is greatly increased. At the discharge side of the impeller, the stream is impinged against the diffuser vanes. The direction of the flow is reversed at the bottom of the hydraulic head where the vanes force an axial turbulent flow as the dispersion/emulsion passes through the annular space formed by the circulation tube and vessel wall. The liquid then flows over the top of the circulation tube and back into the impeller.

Heat transfer oil is circulated in the external heating jacket. High heat transfer coefficients are achieved by the high fluid velocities across the heating surface.


The MAC provides increased efficiency for roofing manufacturers by offering:

•    superior dispersion of fillers
•    reduced time in polymer modification
•    intense mixing capability, enhancing quality through homogenous composition
•    control of air entrainment
•    more precise temperature control
•    reduced energy cost through its heat transfer effectiveness
•    substantially increased production capability
•    reduced maintenance costs
•    less clogs and line shut downs than other mixers
•    operating temperature range of 375-400 degrees Fahrenheit (can be higher, based on request)
 

The MAC was specially designed for high viscosity fluids, due to the high polymer and mineral filler concentration of roofing asphalts.

In the original design the inner circulation tube was not heat jacketed, due to economical considerations. The heat transfer is still great, but with this solution the inner tube is removable. This provides easy cleaning during shutdown or maintenance.
If required, the inner tube could be heat jacketed too.

Any kind of polymer modification could be achieved by incorporating a colloid mill to the MAC.

The MAC could be pressurized as well in order to produce light hydrocarbon content adhesive (solvent based adhesive) that minimizes hydrocarbon vapor loss.



In summary, the MAC is capable of producing the following:

•    any kind of elastomer (e.g. SBS) modified asphalt/bitumen,
•    any kind of plastomer (e.g. APP) modified asphalt/bitumen,
•    anionic or cationic asphalt/bitumen emulsions,
•    light hydrocarbon (e.g. white spirit) containing asphalt for adhesives.
•    High mineral filler content asphaltic adhesives for shingle manufaturing

For further information regarding roofing, please contact us.



Last Updated ( Tuesday, 03 November 2009 21:55 )