The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 13, 1995
Filed:
Dec. 07, 1993
John Milstead, Chattanooga, TN (US);
Astec Industries, Inc., Chattanooga, TN (US);
Abstract
A designated amount of recycled asphalt product (RAP) is fed to the pugmill of a batch asphalt plant during the production of hot mix asphalt (HMA) at a controlled rate so as not to overload the pugmill scavenging system. The designated amount of RAP is metered in a RAP weigh hopper, stored temporarily in a RAP holding hopper, and is then fed from the RAP holding hopper to the pugmill at a controlled rate. The feed of RAP to the pugmill, though electronically initiated, is preferably manually or automatically adjustable so as to avoid overloading the pugmill scavenging system while at the same time assuring adequate mixing of the RAP with the virgin aggregate and liquid asphalt. The scavenging system directs vapors removed from the pugmill to the dryer and preferably includes electronically operated dampers connecting the combustion air inlet of the dryer to the pugmill only during the mixing operation and otherwise connecting the combustion air inlet to the ambient atmosphere.