U. S. Department of Energy, National Energy Technology Laboratory, Office of Research and Development (ORD) Research Activities within the Gasification Program
Development of Reacting Multiphase Models for Advanced Gasification Processes; Experimentation for Model Development and Validation
A prominent part of NETL ORD’s R&D portfolio has been development and validation of models for advanced gasification technology. These models streamline the design of gasifier systems, allowing complex multiphase flow reactor geometries and concepts to be explored early in the development process and evaluated with less empirical testing, yielding improved performance with lowered development time and cost. Read More!
Understanding the performance of flow reactors used in fossil-energy technology and having the means to impact their design in early stages of development is important for two reasons:
(1) About 75% of the manufacturing cost of any product is committed at the conceptual design stage, even when the incurred cost might be very small. Once the conceptual design stage has been completed, the opportunities for cost savings have already diminished. Computational models can be used to simulate the device and understand its performance before the design is finalized, which is important for reducing cost.
(2) During new technology development, empirical scale-up information is not available because reactors at the large scales that are required have not been built. Furthermore, it is well known that traditional scale-up methods do not work well for multiphase flow reactors such as the ones used for gasification. Therefore, science-based models with quantified uncertainty are important tools for reducing the cost and time required for development.
Central to National Energy Technology Laboratory’s (NETL’s) multiphase flow reactor modeling efforts is the laboratory’s computational fluid dynamics (CFD) code—Multiphase Flow with Interphase eXchanges (MFiX)—developed specifically for modeling reacting multiphase systems. This open-source software has over two decades of development history and more than 3,600 registered users worldwide. This software has become the standard test for comparing, implementing, and evaluating multiphase flow constitutive models and has been applied to an extremely diverse range of applications involving multiphase flows. The successes achieved in modeling such complex problems have led to new and improved models that are now available to the modeling community, which feature greatly improved simulations of key attributes within multiphase flow systems such as drag, polydispersity, attrition, and agglomeration models, and other significant advances.
Further information about MFiX is available at NETL’s Multiphase Flow Science web page.
New Concepts for Gasification and Fuel Conversion
ORD intends to accelerate deployment of advanced gasification systems by aligning ORD core strengths with industry’s needs and technology gaps. Studies are supporting technological advancement of novel gasification concepts to
(1) reduce coal gasification costs
(2) increase overall efficiency of gasification systems; and
(3) reduce emissions including carbon.
This work leads toward design of a compact, low temperature, and economically viable gasifier to produce value-added chemicals from coal.
Material Interactions during Gasification
ORD is completing on-going high temperature refractory materials research and implementing it into industry in FY15. Also, low temperature data on ash physical and chemical phases related to particulate agglomeration will be used in modeling efforts discussed above. Refractory material research is focused in two areas:
(1) improving refractory material service life; and
(2) modeling and controlling slag chemistry.
Both of these areas have specific tasks targeting refractory material development, sensor development, ash/slag management, and vanadium phase studies. Ash agglomeration data will be used in models of fluidized bed gasification systems. Ash particles can become sticky during gasification, causing agglomeration in fluidized beds, leading to poor gas flows or gasifier shutdown in fluidized bed systems.
Innovative Technology Concepts
Exploratory studies will be conducted on ideas which emerge over the course of ORD’s research. Studies would be limited to use of existing equipment and staff, as well as work hours spent. Promising ideas emerging from this effort would be discussed with NETL leadership to develop for further study.
A top-down type approach is adopted by NETL ORD for the C&CBTL program for driving the incorporation of more mature technologies into plant-scale polygeneration applications, as well as the creation of transformational technologies for these approaches. Efforts will focus on the following general topical areas and approaches:
- Market evaluations of the immediate and near-term prices and demands for power and the aromatics, olefins, fuels, and industrial chemicals created in a polygeneration plant. Understanding these markets, pricing, and demand over 1-, 5-, and 10-year timelines will help researchers assess the best engineering approaches and chemical products to target with research and development (R&D) efforts.
- Performance and techno-economic assessments of the best-performing technologies for creating chemical products from coal/biomass-based gasification streams. Experimental data at the engineering scale and device-level models will be used to feed into techno-economic assessment models that can properly evaluate performance, scalability, and costs of new polygeneration technologies at the power plant scale.
- Transformational technologies for generating the new chemistries, catalysts, materials, reactors, and chemical processes required to improve the efficiency, carbon footprint, and economics of polygeneration approaches. These efforts will be guided by the market and techno-economic assessments performed in this Coal & Coal Biomass to Liquids FWP, which will help earlier stage R&D activities focus on the most promising product streams and engineering approaches for advancing technologies up to power plant scales.
The successful execution and completion of this research will result in a variety of products, tools, and approaches that will assist the Fossil Energy (FE) program in the deployment of coal biomass to liquids (CBTL) technologies that will surpass both the greenhouse gases (GHG) footprint and economic standards of conventional petroleum processes. Specific impacts and benefits include:
- Market driven R&D efforts which will create the datasets (reaction kinetics, selectivity, deactivation data, reactor evaluation) and device-level engineering models needed to facilitate rapid techno-economic assessments of new polygeneration technologies.
- A techno-economic assessment toolbox that can be used to quickly evaluate the performance, costs, and carbon footprint associated with incorporating new catalysts, reactors, and hybrid systems (catalyst + reactor + membrane) into power plant scale polygeneration applications.
- A portfolio of chemistries, catalysts, and chemical processes that can be used to take advantage of changing gasification feedstocks, shifting market demand/prices for power/chemicals, and altering word politics which may impact energy security.
With these tools, the economic limits of a coal to liquid fuels production plant can be exceeded through the addition of chemicals production for maximum profitability – the most profitable chemical types and quantities will vary on coal type, regional markets, international markets, and other economic drivers.
This work will culminate in market evaluations and techno-economic assessments with specific locations and coal types, a base case for each liquid fuel product, and an alternate case using these tools to add optimal chemical production.
NETL ORD Peer Reviewed Publications
NETL ORD News Magazine