The Valorization of a Crude Refinery’s By-Product: A Case Study on the Heavy Residue Gasifier

Abstract

The conversion of locally available, low-value materials to useful products and media, thereby replacing high-quality and high-cost resources, belongs to one of the pillars of the circular economy of industrial conditions. A study on the potential implementation of a mixed oxygen- and steam-blown heavy vacuum residue gasifier in a refinery, processing 5 to 6 million t of crude oil per year, is performed, evaluating its mass and energy balance, and identifying and assessing the synergies of gasifier placement in a refinery, rather than its erection as a stand-alone plant. Industrial heat and power plants, as well as hydrogen production plants, represent the production units that are directly affected by gasifier implementation, while several other technical and economic issues result in: the operation of the steam network, in heavy residues’ handling, and in the refinery’s natural gas balance. Natural gas is currently the most important resource for hydrogen production in the refinery, and its partial replacement by hydrogen from a gasifier has different energetic and environmental impacts, based on the considered natural gas composition (current situation: natural gas with 10% vol. renewable hydrogen and natural gas with 20% vol. renewable hydrogen content). The power production and the overall refinery’s power balance, the carbon dioxide emissions both within the refinery and external ones, and natural gas balance change are all evaluated. The preliminary results show that while gasifier commissioning is associated with an over EUR 1 billion investment, it can represent one of the few available solutions of how to reasonably dispose of heavy residues, utilizing it from both energy content and material potential point of views.

Keywords

• vacuum residue
• gasification
• hydrogen
• refinery
• carbon dioxide