AP Consultoria e Projetos undertook a project to implement a new diesel hydrotreatment unit (HDT) with a capacity of 10,000 m3/d, in order to adapt refining scheme. This increased the production of S-10 diesel and QAV-1 and aimed to meet the specifications and volumes demanded by the future market, economically, without compromising operational safety or the environment. For the proper operation of the new HDT the implementation of a new hydrogen recovery unit and adaptations in several existing process units in the refinery were foreseen.