In partnership with Bloom Engineering, Industrial Furnace Company is proud to announce that it has received U.S. Patent No. 9,702,022 for de-coating aluminum scrap with a Multiple Hearth Furnace.

The secondary aluminum industry is huge, accounting for nearly 60% of the US aluminum production according to a US Geological Survey. Secondary recovery rates are extremely important, as losses must be replaced with primary metal, which is extremely energy intensive.

There are three main categories of secondary scrap, defined by their volatile organic compounds (VOCs) as a percentage of weight:

  • Low: <5%
  • Medium: 5% - 25%
  • High: >25%

Low VOC scrap (“clean”) that is easier to process is becoming less available, and more expensive, whereas High VOC (“dirty”) scrap is more readily available. Current de-coating technologies frequently have difficult processing higher VOC scrap, creating high specific energy consumption, incomplete removal of coatings, oxidation of the metal, and low recovery rates.

Our patented process has shown that we are able to successfully remove the coatings from many different types of scrap aluminum, including high VOC scrap that is difficult to process with today’s technology. Our testing showed that the aluminum retained its form, and the coatings are completely removed with little evidence of surface oxidation, resulting in extremely high recovery rates.

Check out our patent here:,702,022.PN.&OS=PN/9,702,022&RS=PN/9,702,022