(ShareCast News) - Hydrodec, a specialist re-refiner of industrial oils, has received approval from the American Carbon Registry (ACR) to receive carbon credits for its oil.Typically, carbon credits permits assigned to a firm allow it to produce a certain amount of emissions which can then be traded if the full allowance is not used.The group's patented technology has been approved as a carbon offset project which has in effect created an incremental revenue stream for the company, Hyrdrodec said in a statement.As far as the AIM-listed company is aware this would make it the only oil re-refining business in the world to receive carbon credits for its product.Hydrodec of North America (HoNA) is now generating offsets through the re-refining of used transformer oil which would otherwise be incinerated or disposed of in an unsustainable manner.The ACR has recognized 165,000 credits for HoNA's previous production between 2009 and 2014. The company anticipated it will generate 50,000 to 60,000 tons of carbon offset every year going forward, which the board estimates will generate up to $5 per ton.Chief Executive Chris Ellis said: "ACR approval means that Hydrodec now produces the only oil globally which generates a carbon credit. It is a further demonstration of the world leading nature of our technology and product and reinforces the sustainability element of it to the primary users of transformer oil."Chairman Colin Moynihan added: "Today marks a further important milestone in the Company's progress. Carbon credit approval seals Hydrodec's objective to establish a key role as a clean tech company with genuine market leadership; the first proven 'green oil' technology in the world with the capacity to treat and re-refine used and contaminated oil into high quality, renewable transformer oil."The share price went down 2.96% to 3.28p at 1535 BST on Thursday.