Published December 2019
The refining industry involves some of the most complex chemical process operations and produces a wide variety of products, such as gasoline, diesel, aviation fuel, lube oils, and petroleum coke. Gasoline is probably the most important and visible product of the global petroleum refining industry. As sold by the refineries, the gasoline product is a mixture of hydrocarbon streams from several process units. These streams may include FCC gasoline, catalytic reformates, isomerates, alkylates as well as light gases such as pentane or butane. These streams, each with different characteristics, are blended together to produce the gasoline product with desired properties, subject to certain constraints or specifications, in a most economical way. Gasoline market is heavily regulated by various governments across the globe. Consequently, the economics of gasoline production is closely associated with the dynamics of prevalent government regulations. The emerging global environmental regulations are imposing increasingly stingent constraints on gasoline properties such as octane values, aromatic and olefinic content, sulfur and RVP. In this regard, alkylate has emerged as an ideal blending component due to its combination of high octane value, low sulfur, low RVP and practically no aromatic or olefinic content.
With the above statement in perspective, we present a review and technoeconomic analysis of three processes for alkylate production. The first process is the conventional sulfuric acid process which is well represented by the STRATCOTM process licensed by Dupont. The second process is the CDAlkyTM alkylation process licensed by McDermott (formerly Lummus/CB&I). This process claims to achieve better performance thorough operation at lower temperature. A major breakthrough in recent years in the alkylation technology is the use of ionic liquids as catalyst replacing the notoriously hazardous strong acids, such as hydrofluoric and sulfuric acid. The third process in this report is the ISOALKYTM process developed and licensed by Chevron and UOP, which uses ionic liquids as catalyst. The processing capacity for all three processes is 450,000 MT/year (~992 million lb/year) of alkylate production. This capacity corresponds to approximately 12,200 bbl/day of the alkylate production.
The production economics assessment in this report is based on a US Gulf Coast location. However, an iPEP Navigator module (an excel-based computer costing model developed by IHS) is attached with this report to allow a quick calculation of the process economics for three other major regions also—Germany, Japan, and China. For every process, the module also allows production economics to be reported in English or metric units in each region.
The technological and economic assessment of the processes is PEP’s independent interpretation of the companies’ commercial processes based on information presented in open literature, such as patents or technical articles, and may not reflect in whole or in part the actual plant configuration. We do believe that they are sufficiently representative of the processes and process economics within the range of accuracy necessary for economic evaluations of the conceptual process designs.