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US 4,706,893 AGranted
Method and apparatus for recycling roofing shingles as an additive to asphalt paving composition
AssigneeAstec Industries, Inc.
InventorJames D. Brock
Life of this patent
Estimating the term…
Abstract
A method and apparatus for recycling asphalt shingles in an asphalt plant which heats and dries aggregate and mixes the heated and dried aggregate with liquid asphalt to form an asphalt paving composition. The shingles are comminuted to particles of a size which can be easily flowed and metered, and the shingle particles are introduced into the asphalt plant such that they are heated to melt the asphalt in the shingle particles. The aggregate, heated shingle particles, and liquid asphalt are thoroughly mixed to form an asphalt paving composition.
Claims34
An asphalt plant comprising:
- means for heating and drying measured amounts of virgin aggregate;
- means for comminuting asphaltic roofing shingles having a known percentage by weight of asphalt to particles of a size which can be accurately flowed and metered;
- means for introducing said shingle particles into said asphalt plant such that said shingle particles are heated to melt the asphalt in said shingle particles and mixed with said virgin aggregate to from a mixture;
- means for introducing measured amounts of liquid asphalt into said asphalt plant;
- means for mixing said liquid asphalt with said mixture of shingle particles and virgin aggregate to form an asphalt paving composition;
- means for measuring the amount of shingle particles introduced into said asphalt plant, whereby the amount of asphalt introduced into said asphalt plant as a result of the introduction of said shingle particles can be calculated based upon the measured amount of shingle particles and the known percentage of asphalt in said shingle particles;
- and
- means for controlling the amount of liquid asphalt introduced into said asphalt plant such that the total amount of asphalt in said paving composition from said shingle particles and from said liquid asphalt constitutes a desired proportion of said paving composition.
5 more elements
An apparatus for manufacturing asphalt paving composition comprising:
- a drum mixer mounted for rotation about its longitudinal axis;
- means for continuously introducing virgin aggregate into said drum mixer;
- means for measuring the rate at which virgin aggregate is introduced into said drum mixer;
- means for comminuting asphaltic shingles having a known percentage by weight of asphalt to particles which can be accurately flowed and metered;
- means for continuously introducing said shingle particles into said drum mixer such that said shingle particles are mixed with said aggregate in said drum mixer to form a mixture;
- burner means in communication with the interior of said drum mixer for heating said mixture to heat and dry said aggregate and to melt the asphalt in said shingle particles;
- means for measuring the rate at which shingle particles are introduced into said asphalt plant, whereby the rate at which asphalt is introduced into said drum mixer from said shingle particles can be calculated based upon the measured rate of shingle particle introduction and the known percentage of asphalt in said shingle particles;
- means for continuously introducing liquid asphalt into a section of said drum mixer removed from said heating means such that said liquid asphalt is mixed with said mixture of aggregate and shingle particles to form an asphalt paving composition;
- and
- means for controlling the rate at which liquid asphalt is introduced into said drum mixer such that the proportion of total asphalt in said paving composition from said shingle particles and from said liquid asphalt constitutes a desired proportion of said paving composition.
7 more elements
A method for manufacturing asphalt-aggregate paving composition having a predetermined proportion by weight of asphalt, said method comprising the steps of:
- comminuting asphaltic shingles having a known proportion by weight of asphalt to particles of a size which can be accurately flowed and metered;
- combining a measured amount of shingle particles and a measured amount of virgin aggregate to form a mixture;
- heating said mixture to heat and dry said aggregate and to melt the asphalt in said shingle particles;
- calculating the amount of asphalt in said mixture based upon the measured amount of shingle particles and the known proportion by weight of asphalt in said shingles;
- introducing a controlled amount of liquid asphalt into said mixture such that the amount of total asphalt in said mixture from said shingle particles and said liquid asphalt constitutes said predetermined proportion;
- and
- mixing said aggregate, said shingle particles, and said liquid asphalt to form an asphalt paving composition.
4 more elements
A method for manufacturing asphalt-aggregate paving composition having a predetermined proportion by weight of asphalt, said method comprising the steps of:
- comminuting asphaltic shingles having a known proportion by weight of asphalt to particles of a size which can be accurately flowed and metered;
- combining measured amounts of shingle particles, reclaimed asphalt roadway material having a known proportion by weight of asphalt, and virgin aggregate to form a mixture;
- heating said shingle particles and said reclaimed roadway material to melt the asphalt therein;
- calculating the amount of asphalt in said mixture from said shingles based upon the measured amount of shingle particles and the known proportion by weight of asphalt in said shingles;
- calculating the amount of asphalt in said mixture from said reclaimed roadway material based upon the measured amount of recycle material and the known proportion by weight of asphalt in said recycle material;
- introducing a controlled amount of liquid asphalt into said mixture such that the amount of total asphalt in said mixture from said shingle particles, said reclaimed roadway material, and said liquid asphalt constitutes said predetermined proportion;
- and
- mixing said shingle particles, said reclaimed roadway material, said aggregate, and said liquid asphalt to form an asphalt paving composition.
5 more elements
Dependencies are inferred from the claim text.