Waste Refinery: The Valorization of Waste Plastics and End-of-Life Tires in Refinery Units. A Review

Abstract

This review collects a wide range of initiatives and results that expose the potential of the refineries to be converted into waste refineries. Thus, they will use their current units for the valorization of consumer society wastes (waste plastics and end-of-life tires in particular) that are manufactured with petroleum derivatives. The capacity, technological development, and versatility of fluid catalytic cracking (FCC) and hydroprocessing units make them appropriate for achieving this goal. Polyolefinic plastics (polyethylene and polypropylene), the waxes obtained in their fast pyrolysis, and the tire pyrolysis oils can be cofed together with the current streams of the industrial units. Conventional refineries have the opportunity of operating as waste refineries cofeeding these alternative feeds and tailoring the properties of the fuels and raw materials produced to be adapted to commercial requirements within the oil economy frame. This strategy will contribute in a centralized and rational way to the recycling of the consumer society wastes on a large scale. Furthermore, the use of already existing and, especially, depreciated units for the production of fuels and raw materials (such as light olefins and aromatics) promotes the economy of the recycling process.

Conversion of HDPE into Value Products by Fast Pyrolysis Using FCC Spent Catalysts in a Fountain Confined Conical Spouted Bed Reactor

“…[66] Accordingly, this fraction may be processed in hydrocracking units for reducing aromatic and olefin content. [15] In this case, the RON index [69] of the C 5 À C 11 fraction obtained is in the 87-88 range and is hardly influenced by the reaction temperature. Thus, temperature affects the yield of products but only has a slight influence on the composition of the C 5 À C 11 fraction.…”

“…In this scenario, thermochemical conversion technologies for plastics waste recycling represent promising alternatives,[ 12 , 13 , 14 , 15 ] as they allow producing fuels and high value‐added chemicals, and therefore boosting circular economy by reintroducing these wastes into the production cycle. In addition, pyrolysis addresses one of the disadvantages of mechanical recycling, as it is suitable for treating mixtures of plastics of different nature.…”

Energy recovery of waste plastics into diesel fuel with ethanol and ethoxy ethyl acetate additives on circular economy strategy

“…Physical and chemical treatments must be widely implemented in order to be commercially sustainable. The proposed approach by Palos et al 47 suggests establishing a new waste management business network. The oil industry would gain from the business network's commitment to sustainable development.…”

Opportunities and challenges for the application of post-consumer plastic waste pyrolysis oils as steam cracker feedstocks: To decontaminate or not to decontaminate?

“…Many different (petro-) chemical treatment options for plastic waste pyrolysis products have been researched in the past including the conversion to transportation fuels ( Nanda and Berruti, 2021 , Papari et al, 2021 ), or to feedstocks for fluid catalytic cracking ( Rodríguez et al, 2019a , Lee, 2009 , Rodríguez et al, 2019b ), hydrocrackers ( Joo and Guin, 1997 , Li et al, 2016 ) or coker units ( Palos et al, 2021 ). Obviously, the conversion of plastics to fuel results in a low value product which makes it economically very challenging to compete with, for example olefin production, not even considering the circularity of fuels.…”