Techno-economic analysis of carbon dioxide capture and utilisation analysis for an industrial site with fuel cell integration

Abstract

The emergence of global warming phenomena that has adversely affected the world today has been largely attributed to the proliferation of greenhouse gases, with Carbon dioxide, as its main constituent. The challenge to reduce the Carbon dioxide footprint can be overcome by increasing the value of Carbon dioxide emissions by creating subsidiary industries that can utilize Carbon dioxide as its raw materials and producing other added-value products that can be utilised within the industrial site. The study proposes a framework that sequences the process of evaluating the CO2 footprint and proposing CO2 reduction measures to decrease the CO2 footprint of an existing industrial site. The framework considers an economic sustainability of a multipronged CO2 utilisation approach that includes a fuel cell configuration. Fuel cell is an efficient electrical energy generation technology that can also supplement the electrical needs of a site. The objective of this study is to conduct a techno-economic investigation of the feasibility of including subsidiary plants producing methanol, Calcium carbonate and baking soda from the carbon dioxide captured from the flue gas in the industrial site. This paper investigated the cost of capturing carbon dioxide from selected plants within the industrial site and determined the operating and capital cost required using a bottom-up approach from mass balances. The energy and power cost were interpolated from data obtained from similar waste to resources plants. From the methanol produced, it was determined that a maximum potential of 4.4 MWh per day of electricity can be produced from a Direct Methanol Fuel cell, configuration. It was determined that the cost of producing methanol and calcium carbonate would only be sustainable if the price of raw materials such as hydrogen and wollastonite could be brought down by producing hydrogen through solar-chemical water splitting and the wollastonite from steelmaking slag. The baking production was determined as the most sustainable subsidiary industry in the carbon capture and utilisation, CCU framework with an annual rate of return on investment of 12%. The sustainability of the Carbon capture and utilisation system proposed depends on the reduction of certain raw material costs and the carbon tax alleviation funds. The findings could serve as a guide for future industrial site planning when inviting CO2 fixing plants to join in the subsidiary industry.