Research

1. Integrated Farm-Based Biorefinery (IFBBR)

In response to the needs for the improvement of biorefinery efficiency and the environmental benefits realized from the treatment of agricultural residues, a novel integrated farm-based biorefining concept is being developed to co-produce alcohols, methane, and other value-added products on a combined feedstock stream of different agricultural residues. The concpet integrates anaerobic digestion (AD), algal cultivation, and value-added chemical/fuel production. The AD process pre-treats the fiber in agricultural residues for feedstock preparation. The algal cultivation on AD effluent further reduces the environmental impacts of odor and excess nutrients associated with anaerobic digestion, and generate a starch and protein riched biomass. Finally, advanced bioprocesses utilize the carbohydrates in AD treated fiber and algal biomass to produce alcohols, fatty acids, and other intermediates for chemical and fuel production. This integrated biological process for agricultural residue utilization leads to reducing our reliance on fossil fuel while simultaneously maximizing the farmers’ interests and minimizing environmental impacts.

Integrated Farm-Based Biorefining Concept

2. Solar-Bio-Nano-Based wastewater Utilization System

The goal of this project is to integrate solar, biological, and nano technologies into wastewater treatment concept to create a self-sustaining wastewater treatment system that can significantly reduce mass of the wastewater, and simultaneously generate potable water/renewable energy/fertilizer. The proposed system includes five subunits of solar energy collection, novel anaerobic digestion, combined heat and power unit, electrocoagulation pretreatment, and nano-filtration. The integrated concept has a great potential to be applied by a wide range of waste treatment systems from agricultural wastewater to municipal wastewater treatment. The use of such novel technology would dramatically change the status of wastewater treatment. It will eventually turn the wastewater from an environmental liability into a public and private asset.

Pilot-scale solar-bio-nano-based wastewater utilization system

3. Anaerobic Digestion of Organic Residues

Vast amounts of agricultural residues produced in the United States have the potential to be converted into economic gain if the proper processing technology is employed. Anaerobic digestion (AD) is such a technology. It not only can provide pollution prevention, but also converts the residues into profitable bioenergy and chemcial products, namely, methane biogas, fiber, and digestate, each which can be used, respectively, as fuel, soil amendment, and liquid fertilizer. AD is an established technology but low growth rates of anaerobic bacteria and difficulties with biodegradation of lignocellulosic materials are stifling wide adoption of AD in waste management. The project is to develop an innovative AD system with enhanced cellulosic degradation related microbial community for agricultural residues. The specific objectives are: (1) identifying the current available hemicellulose/lignin related microorganisms in the anaerobic digestion system using advanced genetic technologies, (2) investigating the effects of hemicellulose and lignin degradation on biogas production, (3) developing and optimizing the design of an novel plug flow anaerobic digestor with enhanced microbial community for cellulose degradation.

Figure. Microbial community analysis

4. Value-added Energy/Chemical Products from Algae Cultivation

Mass cultures of microalgae are suitable for production of renewable chemicals and fuels, and for CO2 fixation and water purification. The combination of production of renewable materials with environmental applications is one of major advantages of microalgal culture. It supports sustainability and process economy. Currently, we at the department of Biosystems and Agricultural Engineering Department are working on enhanced algal cultivation to sequester CO2, utilize nutrients in waste streams, and produce value-added biofuels/chemicals (Figure). The components from algae we are targeting are lipid, starch, and protein. Our research combines laboratory and pilot studies to determine the factors that influence the growth and composition of microalgae in both fresh water and agricultural/industrial wastewater, and further develop processes to convert these components into fine chemicals and fuels such as plastics, enzymes, biodiesel, and ethanol etc. The research topics include:
• Lipid production from cold-adapted algae cultivation;
• Microalgae system for enhanced starch-based ethanol production;
• Improving energy efficiency and generating high-value co-products from an integrated anaerobic digestion and algae cultivation system.

Figure. Algal culture for value-added energy/chemical products