Economic Assessments of Hydrogen Production Processes Based on Natural Gas Reforming with Carbon Capture

Abstract

Hydrogen is a promising energy carrier for future low carbon economy as fuel or chemical for various industrial applications (e.g. heat and power, petro-chemical, metallurgy etc.) as well as for transport sector. In order to decarbonise the energy sector as well as the transportation sector, the fossil fuels need to be efficiently converted to hydrogen and the resulted CO2 to be captured and then used / stored. The Carbon Capture, Utilisation and Storage (CCUS) technologies are promising options of efficiently combating climate change (by significantly reducing the greenhouse gas emissions) as well as continuing of using the fossil fuels. This paper is assessing the key updated technical and economical performances of hydrogen production based on natural gas reforming with and without carbon capture. As illustrative examples, conventional steam reforming and autothermal reforming (using both oxygen and air) of natural gas were evaluated. The CO2 capture technology was based on pre-combustion capture configuration using gas-liquid absorption. As illustrative cases, Methyl-DiEthanol-Amine (MDEA) as a chemical solvent and SelexolTM as a physical solvent were assessed for their performances. The evaluated hydrogen production concepts have a capacity of 100,000 Nm3/h (corresponding to 300 MWth based on lower heating value) with a purity higher than 99.95 % (vol.). The paper presents in details the evaluated hydrogen production concepts based on natural gas reforming, modelling and simulation aspects, model validation, mass and energy integration issues as well as proposing an integrated methodology for quantification of key economic aspects. As the results show, the conventional steam reforming has higher energy utilisation factor (about 5 net percentage points) than the autothermal reforming cases. The carbon capture rate is about 65 - 70 % for the conventional steam reforming considered as an illustrative case. The economic indicators show better performances for conventional steam reforming in comparison to autothermal reforming in term of specific capital investment cost (about 12 - 24 % lower), operational and maintenance costs (about 7 % lower), hydrogen costs (about 5 - 10 % lower). Physical absorption is more energy and cost effective than chemical absorption as pre-combustion capture method.