Modular Refineries Offer Advantages for Product Availability in Nigeria

_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 211932, “Imperatives of Modular Refineries and Their Impact on Product Availability in Nigeria,” by Evelyn Bose Ekeinde and Adewale Dosunmu, SPE, Federal University Otuoke, and Diepiriye Chenaboso Okujagu, University of Port Harcourt, et al. The paper has not been peer reviewed. _ Nigeria is rich in crude oil, with a proven reserve of 37 billion bbl. Despite the abundance of this resource, Nigeria has lacked the capacity to meet the country’s demand for petroleum products locally and has resorted to their importation. Establishing conventional refineries is highly capital-intensive, and they take a significant amount of time to build and commission. The modular refinery option is a less capital-intensive alternative. The complete paper discusses the promise of modular refineries and their potential effects on the availability of petroleum products in Nigeria. Introduction Despite its large reserves of crude oil and a combined in-country refining capacity of 445,000 B/D from four state-owned refineries, Nigeria has been plagued with challenges in local refinement. These refineries have operated grossly below installed capacity for decades, operating at a capacity hovering between 15 and 25%. The inability to harness local refining to meet demands for petroleum products has turned Nigeria into a net importer. Modular Refineries A modular refinery is a processing plant composed entirely of skid-mounted structures, each of which comprises a part of the entire processing plant. Various components are connected through interstitial pipes to create a highly manageable process. They are smaller than conventional refineries, with processing capacities ranging from 1,000 to 30,000 B/D. Essentially, modular refineries are mini-refineries. Modular topping plants or crude distillation units are the most straightforward and cost-effective method of extracting valuable fuels from crude oil. Within 14 months of contract execution, a topping plant can be operational, providing host communities with vital fuels for automobiles, power generation, and job possibilities. Furthermore, construction of a modular refinery is less capital-intensive, ranging from $1 million to $15 million, compared with a conventional refinery, which could cost up to hundreds of millions or even billions of dollars, depending on the refinery’s complexity and configuration. Many configurations featuring different degrees of sophistication exist for modular mini-refineries. They include the following: - Atmospheric topping unit—This is an inexpensive distillation unit that can make diesel and kerosene from raw crude oil. Naphtha and fuel oil also can be byproducts. - Topping unit with gasoline train—This option features the addition of regenerative agents or hydrotherapy, thus producing high-octane unleaded gasoline and high-octane liquefied petroleum gas. This configuration can put together isomerization units to make more premium unleaded gasoline. It also can make more gasoline with a higher octane rating. - Vacuum distillation unit—The addition of a second distillation tower to separate the fuel components from the atmospheric tower results in clean heavy diesel (vacuum gas oil) and dirty heavy residual oil. - Hydrocracker unit, full conversion—The hydrocracker unit (which has a high capital cost) transforms light and heavy gas oils into more-marketable products with a lower boiling point. The yield of a hydrocracker unit may add to the profitability of a refinery.