Abstract:
CAMD is the reverse use of the group contribution method to generate molecules with desirable properties. The group contribution method (GCM) is a technique to estimate and predict thermodynamics and other properties from molecular structures. This approach dramatically reduces the amount of data needed. Instead of requiring information on thousands or millions of components' properties, data for only a few dozen or a few hundred groups are needed. A GCM uses the principle that some simple chemical components' structures are always the same in many different molecules. The smallest common constituents are the atoms and the bonds. For example, all-organic components are built of carbon, hydrogen, oxygen, nitrogen, halogens, and sometimes sulfur. Together with single, double, and triple bonds, only ten atom types and three bond types are necessary to build thousands of components. The next slightly more complex building blocks of components are functional groups, which are themselves built from a few atoms and bonds. The problem is a combinatorial optimization problem, which is a difficult optimization problem. We have used a new optimization framework to solve real-world problems of CAMD for various separations encountered in chemical, pharmaceutical, and environmental industries. In this talk we present a new technology for removal of various contaminants from produced waters of Oil and Gas industries.
The geologic formations that contain oil and gas deposits also contain naturally-occurring radionuclides, which are referred to as Naturally Occurring Radioactive Materials (NORM). Oil and gas fracking brings NORM to the surface in a concentrated form, which could pose a radiation safety hazard. Further, NORM levels have the potential to climb over time as the fluid being extracted begins to contain proportionally greater amounts of brine. Therefore, the majority of produced water contains significant levels of NORM. In 2011, GTI carried out a Techno-economic Assessment of Water Management Solutions project (2011) supported by a consortium of 23 companies. This consortium identified many priority industrial challenges for the pre- and post-crossover stages of a shale gas development area's water-based life cycle and identified NORM removal as one of the highest priority research areas. They also ascertained that there is currently no commercial product on the market to remove NORM from concentrated produced and flowback waters selectively. In this work, we have used CAMD to design novel clay-based adsorbents for removal of NORM from produced water. With NSF funding, we then synthesized the adsorbents in the laboratory to show the effectiveness of CAMD. The new adsorbents perform an order of magnitude better than existing adsorbents for NORM removal. We carried out these experiments using produced water from Permian Basin. The concentration of NORM (Radium) in this water was more than 4000 pCi/g. According to regulations, the acceptable quantity of NORM for groundwater is 30 pCi/g. With our novel adsorbents, we could remove NORM from this water to the limit undetectable. The cost of adsorbent is minimal. Further, the NORM disposal cost with this approach is expected to be 1/7-th of that of the current NORM disposal cost.
We also found novel adsorbents to remove Arsenic, Barium, and Strontium effectively from the produced water. Results for this will also be presented.
The key takeaway from this presentation are:
- A novel technology to remove NORM and other contaminants from produced waters.
- This provides a cost-effective removal of NORM, Barium, and Strontium.
- The NORM disposal cost is also minimum with this technology.
Speak Bio:
Prof. Urmila Diwekar is the president of the Vishwamitra Research, a non-profit research institute that she founded to pursue multidisciplinary research in the areas of Optimization under Uncertainty and Computer-aided Design applied to Energy, Environment, and Sustainability. From 2002-2004, she was a Professor in the Departments of Chemical Engineering, Bio-Engineering, and Industrial Engineering, and in the Institute for Environmental Science and Policy, at the University of Illinois at Chicago (UIC). She has made major contributions to research on batch distillation, advanced power systems, sustainability, environmental management, nuclear waste disposal, molecular modeling, pollution prevention, renewable energy systems, and biomedical engineering. Her recent work extended her work on stochastic modeling and optimization of particulate processes in chemical engineering to biomedical engineering especially to In-Vitro Fertilization. She is the author of more than 170 peer-reviewed research papers, and has given over 350 presentations and seminars, and has chaired numerous sessions in national and international meetings. She has been the principal advisor to 41 Ph.D. and M.S. students, and has advised 13 post-doctoral fellows and researchers. During the past ten years, her students have won 6 best student paper awards from various AIChE and INFORMS sections at their respective meetings. In November 2011, she received the Thiele award for outstanding contributions to chemical engineering, awarded by the Chicago chapter of AIChE. In 2015 she received one of the most prestigious awards of AIChE (an Institute award), the Energy and Sustainability award for leadership in research related to conventional energy, renewable energy, energy-water nexus, carbon capture and environmental control for energy, pollution prevention, and sustainability.