Team:Brasil-USP/Practices/RECUR
RECUR Environmental Solutions
Policy and Practices
Visit to RECUR Environmental Solutions 29/08/2015
Our team participated in a guided visitation to RECUR Environmental Solutions. The company aims to market by-products from tire pyrolysis, but is not currently active as it is awaiting authorization from government agencies (CETESB). RECUR spent the last two years conducting tests to improve tire pyrolysis, maximizing the achievement of the by-products generated in the process. To conduct these tests, tires were obtained from local tire repair stores.
To carry out the pyrolysis of tires, RECUR has a industrial equipment similar to a pressure cooker - a type of reactor that is capable of processing two tons of tires per day (a tire ton is equivalent to approximately 14 truck tires and 20 car tires). The pyrolysis cycle begins with a heating step, which lasts for about two (2) hours; when the equipment reaches a certain temperature, the tires begin to decompose; and with four (4) hours of heating maximum temperature is achieved; then the pot is maintained for four (4) hours at maximum temperature until all rubber is decomposed and the oil required to obtain quality products is extracted. Then the cooling of the material is performed, which takes four (4) hours; Meanwhile, another tire load is added to the reactor, reducing the heating time and total required period into two (2) hours. After cooling, the pot can be opened and the process of separation of wire and coal begins.
The byproducts of the pyrolysis process are: coal, oil, LPG and wire. The coal and the wire remain in the "pot" after the process, and oil and LPG are obtained from the gaseous fraction that exits the reactor through a pipe passing through a condensing system. Currently the main marketed by-products of RECUR consists in coal and oil, which must be free of any moisture and odor to have commercial value. The oil can be sold as an additive - but first it needs to pass through a process of impurities separation. The wire generated by pyrolysis is unlikely to be marketed by the company due to its composition - which only has commercial value in another Brazilian state, and the carrying value of the material makes the sale is economically viable only in large quantities. In turn, the LPG is burned while leaving the chimney after the oil separation in the condenser, and coal passes through a milling process to meet the specifications required for commercialization. Each ton of processed tire generates about 320 kg of coal, 350 L of oil, 180 kg of LPG gas and 150 kg wire, products valued at R$ 1200 (approximately US$ 350). The value spent on processing depends on the amount of procedures performed per month.
A major advantage of the pyrolysis method used by RECUR is that devulcanization and grinding steps are not required. The devulcanization processes usually generates coal and oil with inferior quality, since they reach the end of the process with higher humidity than the desired; while grinding generates little waste metals that decrease the quality of coal. Also, in RECUR, the reactor is loaded with whole tires, eliminating the granulation of the material stage - which leads to a lower expense with electric energy and employees.
Due to various technical problems, the reactor may not reach the desired temperature, and in this case, some oil is extracted from the tire and there is not the generation of carbon, leaving the material "rubbery". This material can not be reused in the pyrolysis process and is discarded. We imagine that the bacteria developed by our team can act on this material, generating economic value from a compound would not be used. Thus, samples will be obtained for future tests.