Process design evaluation of an optimum modular topping refinery for Nigeria crude oil using hysys® aspen software

Abstract

Industrially, unprocessed crude oil has little or no value. Hence, there is need for a country to have operational petroleum refineries. According to the Nigerian National Petroleum Corporation annual bulletin, it is expected to have a total refining capacity of 445,000 barrels of oil per day from Nigeria’s four conventional refineries. However, the country still records scarcity of refined products as none of the refineries can boast of working above 60% of its design capacity. In an attempt to provide, a solution to the worsening scenario above, modular refineries setup at strategic positions within the country can help. This will boost 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, Bonny Light, Bonny Medium, Brass and Qua Iboe crude assay. Crude oil characterization using HYSYS® ASPEN was done based on their true boiling points 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 Niger Delta Petroleum Resources crude will favour the production of liquefied petroleum gas, 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.

Keywords

• hysys
• modular
• nigeria
• refinery and topping