From C3 to C5 Feedstocks, Alkylation Units Are Being Designed for Greater Flexibility to Take Advantage of Market Dynamics

摘要

Market dynamics are changing the way refiners are looking at their alkylation units. CAFÉ standards and Tier III requirements are clearly driving the need for additional alkylation capacity in North America. The processing of propylene and amylenes is already widely practiced in North American refineries. However, refiners have the opportunity to create additional value by increasing alkylation capacity using already available olefins. The processing of opportunity feedstocks, such as propylene and C5 olefins, can be extremely profitable for refiners with a well thought-out operating strategy. Propylene alkylation will become increasingly important as additional propylene production capacity comes on line, putting additional pressure on refinery propylene prices. Alkylation of Fluid Catalytic Cracking (FCC) C5 olefins upgrades inexpensive and widely available butanes into gasoline. It also has the positive effect of reducing the RVP of the gasoline pool. The use of field butanes to manufacture on-purpose alkylate is also discussed in this paper. While the alkylation of propylene and amylenes has been practiced for years in North America, technological barriers have limited the economic benefits and more widespread adoption of processing these opportunity feeds. Higher acid consumption rates, additional waste streams, environmental and safety concerns, lower alkylate yield, lower alkylate octane value and increased corrosion rates are just a few of the constraints that have challenged conventional alkylation units, thus curbing refiners' enthusiasm in alkylating these opportunity feeds. CB&l's portfolio is uniquely positioned to respond to the challenges refiners face today. In this paper, CB&I provides innovative strategies and means to enhance refiners' value creation by alkylating opportunity feedstocks with CDAIky® technology.