Research
Discussed below are examples of some ongoing projects in Khanna research group.
Environmental Sustainability of Emerging Biofuels and Biobased Products
Depleting fossil fuel resources, environmental degradation, and unintended detrimental environmental impacts of first generation biofuels have led to the development of low carbon transportation fuels from sustainable biomass feedstocks a top priority. Several pathways are being considered to convert biomass into renewable transportation fuels. While significant attention has focused on developing various biofuel pathways, life cycle environmental impacts of emerging biofuel systems are not well understood. Our research group is investigating the life cycle environmental impacts of emerging biofuel technologies. We develop and integrate models and data from multiple scales ranging from detailed process based models of biomass conversion, biomass production, to life cycle scales. The overall goal of this work is to understand the environmental impacts of emerging biofuel technologies early in the research and development stage and target hotspots for improvement opportunities.
Understanding Resilience in Complex Systems
Our work in this area is focused on developing a fundamental understanding of resilience in complex systems. We are developing methods and metrics for understanding resilience in complex systems from a systems perspective and its implications for sustainability. We integrate tools and techniques from multiple domains including social network analysis, industrial ecology, systems ecology, and applied statistics for a quantitative understanding of resilience in complex engineered systems. We have completed several studies in this area focusing on understanding and developing resilience metrics and methods for industrial symbiosis networks, critical infrastructure sectors, and transportation networks (metro rail). Several additional systems are currently under investigation.
Nexus Challenges
In collaboration with Radisav Vidic at U Pitt, we are investigating the feasibility of waste heat in conjunction with membrane distillation technology for treating the high salinity wastewater produced by the unconventional shale gas industry. Our research findings indicate that vast quantities of waste heat is available at existing natural gas compressor stations in the U.S. We are now developing techno-economic models for large-scale membrane distillation plants for treating high salinity produced water. In addition, current work is in progress to develop decision-support models for environmentally conscious management of produced water in the context of Marcellus shale gas plays.
Ecosystem Goods and Services
While traditional LCA has become the preferential method for evaluating
the life cycle environmental impact of products and processes, it fails to
account for the contribution of natural capital within product and process
life cycles. Natural capital includes goods and services provided by
ecosystems and the natural environment, which are essential to sustaining
human and ecological life. One of the critical ecological supporting services
is pollination provided by insects (both managed and wild species).
However, in recent years, increased habitat loss, reduction in available
forage sources, climate change, monotonous diets, stressful management
practices and vulnerability to pests has placed heightened stress on
pollinator species. We are developing a novel framework for quantifying
the direct and indirect economic dependencies of the U.S. economy and
industry sectors on insect-mediated (managed and wild insects) pollination
service using Input-Output techniques. The data and methods developed
will be broadly applicable for evaluating the economic importance of
pollination services to the world economy, as well as evaluating other
ecosystem goods and services.