Process Design Evaluation of an Optimum Modular Topping Refinery for Nigeria Crude Oil Using HYSYS Software

Abstract

Abstract Industrially, unprocessed crude oil has little or no value; hence there is the need for any country to have operational petroleum refineries to convert the crude oil from its original state into more useful product. According to the Nigerian National Petroleum Corporation (NNPC) 2001-2013 annual bulletin, even with a total refining capacity of 445,000 bopd (barrel of oil per day) expected from the Nigeria four conventional refineries, the country still records scarcity of refined products as none of the refineries can boast of working above 60 percent of its design capacity. In an attempt to provide solution to the above worsening scenario, modular refineries set up at strategic positions within the country can help to boast refining capacity. Although different modular topping refinery configurations exist, this paper examines the simple, pre-flash and the pre-flash pump around reflux scheme in terms of maximum product yield using the Niger Delta Petroleum Resources (NDPR), Bonny Light, Bonny Medium, Brass and Qua Iboe crude assay. Crude oil characterization using Aspen Hysys was done based on their true boiling point to determine the maximum liquid volume fraction of the different distillates. Simulations of the different crude assay were carried out on the different topping refinery configurations highlighting the variation between characterized and simulated volumetric cuts. The result shows that NDPR crude will favour the production of LPG, light naphtha and diesel. Bonny medium crude will favour the production of gas oil and residue oil while qua iboe and brass will favour the production of kerosene and heavy naphtha respectively. The best scheme for different distillates was also determined