Technicians make adjustments to equipment in the hydrogen membrane testing unit at FE's National Energy Technology Laboratory. NETL researchers in the Office of Research and Development are testing different types of materials that might be used to separate hydrogen from other gases. Photo courtesy of NETL.
Hydrogen from coal research supports goals of increasing energy security, reducing environmental impact of energy use, promoting economic development, and encouraging scientific discovery and innovation by researching and developing novel technologies that convert the nation’s abundant coal resources into hydrogen. The use of coal — America’s largest domestic fossil energy resource — offers the potential to economically produce hydrogen and capture carbon dioxide emissions for the generation of low-carbon electricity.
Hydrogen can be produced from coal by gasification (i.e., partial oxidation). Coal gasification works by first reacting coal with oxygen and steam under high pressures and temperatures to form synthesis gas, a mixture consisting primarily of carbon monoxide and hydrogen. The synthesis gas is cleaned of impurities and the carbon monoxide in the gas mixture is reacted with steam via the water-gas shift reaction to produce additional hydrogen and carbon dioxide. Hydrogen is removed by a separation system and the highly concentrated CO2 stream can subsequently be captured and sequestered. The hydrogen can be used in a combustion turbine or solid oxide fuel cell to produce power, or utilized as a fuel or chemical feedstock.
Gasification of coal is a promising technology for the co-production of electric power and hydrogen from integrated gasification combined-cycle (IGCC) technology. However, there currently are no commercial demonstrations of these joint power and hydrogen plants. Conceptual plants have been simulated using computer models to estimate technical and economic performance of co-production facilities.
To reduce costs, novel and advanced technology must be developed throughout the entire system that produces hydrogen from coal. For example, carbon dioxide produced in the hydrogen production process could be sequestered by technologies now being developed in DOE’s Carbon Sequestration Program and eventually demonstrated in other activities by the Office of Clean Coal.
Research and Development (R&D) Needs
The hydrogen from coal production R&D activities include: advanced water-gas shift technologies, hydrogen separation, process intensification, and demonstrations.
- Advanced water-gas shift technologies will focus on the development of more active and impurity-tolerant shift catalysts and technologies that integrate water-gas shift and hydrogen separation into a single step
- Advanced hydrogen separations will explore technology for advanced pressure swing adsorption (PSA), membranes, solvents, reverse selective systems, and other technology alternatives. Areas of focus will be the identification of low-cost materials, stabilization of membranes, membrane seal and fabrication technologies methods for module preparation and scale-up, and analysis of current status and preferred separation options.
- Process intensification is the concept of integrating several processes into one step, such as synthesis gas clean-up, water-gas shift, and hydrogen separation will be investigated. Novel, "out-of-the-box" concepts will also be studied that produce hydrogen from coal.
- Demonstrations will be performed to test advanced technologies to confirm laboratory, bench-scale, and pre-engineering module results.
The R&D activities performed under the Hydrogen from Coal Program will develop advanced technology for use in future electric power and co-production plants.
Benefits of Producing Hydrogen from Coal
The United States has an abundant, domestic resource in coal — nearly a 250-year supply based on current estimates. The production of hydrogen from coal offers efficiency and environmental benefits when integrated with advanced technologies in coal gasification, power production, and carbon sequestration. The integration of these technologies facilitates the capture of multiple pollutants such as sulfur oxides, nitrogen oxides, mercury, and particulates, as well as greenhouse gases such as carbon dioxide.