Crude Distillation Pro Forma

Petroleum refineries have grown rapidly in complexity and so, too, the refinery operations. However, the published information on the refinery processes and operation is scant and mostly confined to licensor's data, which reveal little beyond what is absolutely necessary for process sale, even when these processes have been in operation for a number of years and in many refineries. This book is an overview of the processes and operations concerned with refining of crude oil into products. The streams coming from processing units are not finished products; they must be blended to yield finished products. The refining operations presented here are those concerned with blending products in an optimum manner with the twin objectives of meeting product demand and maximizing refinery profit. The objective here is to provide basic instructions in refinery practices employing the methods and language of the industry.

Presented in the book are refinery processes, such as crude desalting and atmospheric and vacuum distillation; gasoline manufacturing processes, such as catalytic reforming, catalytic cracking, alkylation, and isomer-ization; hydrodesulfurization processes for naphtha, kerosene, diesel, and reduced crude; conversion processes such as distillate and resid hydrocrack-ing; resid conversion processes such as delayed coking, visbreaking, solvent deasphalting, and bitumen manufacture; pollution control processes such as sulfur manufacture, sulfur plant tail gas treatment, and stack gas desulfur-ization. Also presented here are operations performed in refinery off-site facilities, such as product storage and blending, refinery steam and fuel systems, refinery boiler feedwater treatment, and wastewater treatment.

The process details include process flowsheets, process description, chemistry involved, detailed operating conditions, process yields and utilities. Among the refinery operations and practices presented are product blending, refinery inventory forecasts, spreadsheet and LP modeling of refineries, and methods for pricing crude oil, petroleum products, and intermediate stocks.

It must be recognized, however, that many variants of the same process are found in the industry, and the operating conditions can be quite diverse, depending on the type of catalyst used and feedstock processed. We have insufficient space for bibliographic comparison and evaluations of identical basic processes from different licensors. The data presented here represent typical industrial operations practiced in refineries today. Where no mention is made of recent contributions to the literature, no slight is intended. The few references quoted are those where an industrial practice is known to have originated.

Another important subject presented in this volume is concerned with the operation of joint ownership refineries. Building a grassroots refinery requires large capital investment. It is feasible for two companies to own and operate a refinery as if it were build of two independent refineries. Each company may operate its share of the refinery virtually independent of other; that is, each company may bring in its own feedstock and produce product slate independent of the other with no need to build separate product storage facilities for the two companies.

The basic rules of operations of joint ownership refineries is discussed in this book. A typical pro-forma processing agreement between the participants is presented in the Appendix of this book. This covers detailed procedures for refinery production planning, product allocation, inventory management, and allocation of refinery operating cost to participants. Product allocation is the split of total refinery production among the participants on the basis of the feedstock processed by each. Keeping in view that the participants do not process identical feedstocks or produce identical product grades, product allocation for establishing the ownership of stock, must be done at the end of every month. This is a complex exercise and a detailed procedure for this is presented in a separate chapter.

The methods for preparing inventory forecasts and tracking refinery operating expenses in a joint ownership refinery scenario are presented as well. Even though such practices—product allocation, inventory and ullage allocation, operating costs allocation—exist in refining industry, there is no known literature examining them.

Was this article helpful?

0 0

Post a comment