Ruihong Zhang
Ph.D., Agricultural Engineering, University of Illinois at Urbana-Champaign, 1992
Department of Biological and Agricultural Engineering
3046 Bainer Hall
Phone: 530-754-9530
Email: rhzhang@ucdavis.edu
Professor Zhang's research in bioenvironmental engineering focuses on organic waste management and air quality control. The organic wastes include food scraps, agricultural and food processing by-products, animal manure, municipal organic residuals, etc. The goal is twofold: first, to prevent environmental pollution that may be caused by disposal of wastes, and second, to convert these materials into valuable products, such as biofuels and biochemicals. In Professor Zhang's laboratory, effective biological and chemical technologies are applied to engineering systems. Current research areas include the following: 1) developing efficient biological conversion systems to recover energy and producing value-added products from organic wastes, 2) investigating effective, integrated wastewater treatment systems for pollution control, and 3) developing computer models for predicting air emissions from waste sources.
Bacteria and enzymes are studied for conversion of various organic wastes into biofuels (methane, hydrogen, ethanol and biodiesel) and biochemicals (sugars and organic acids). Advanced anaerobic digestion systems have been developed. Innovative research approaches are taken to increase bioconversion efficiencies, improve process stability, and create multiple valuable products so that the overall economics of anaerobic digestion systems can be improved. The research topics include engineering, testing and modeling of innovative bioreactor designs, selection and improvement of bacterial culture, and controlling and monitoring of process conditions. New technologies that are recently developed include anaerobic-phased-solids-digester system (APS-Digester) for solid waste treatment and anaerobic mixed biofilm reactor (AMBR) for liquid waste treatment. Both digestion systems are being scaled up for commercial applications. Integrated wastewater treatment systems are also under development for treating animal wastewater and food processing wastewater. Biological, physical, and chemical treatment processes are studied and integrated to achieve effective treatment of wastewater for air and water quality control.
Effective means for quantifying and reducing air emissions from waste management systems are also researched. Both laboratory and field experiments are conducted to evaluate different waste management practices for air emissions and computer models are developed to predict the emissions rates of various gases (methane, ammonia, hydrogen sulfide, and volatile organic compounds) from animal feeding operations under different waste management and environmental conditions. The computer models are used to estimate and predict the gaseous emissions from animal farms and design effective emission mitigation techniques.
Representative Recent Publications
Zhang, R.H., T. R. Rumsey, J.R. Fadel, J. Arogo, Z. Wang, G.E. Mansell, and H. Xin. 2005. A process-based ammonia emission model for confinement animal feeding operations – model development. Paper presented at 14 th Annual Emission Inventory Conference. April 11-15, 2005. Las Vegas.
Zheng, Y., Z. Pan, R.H. Zhang, B.M. Jenkins, and S. Blunk. 2005. Properties of medium-density particleboard from saline Athel wood. Industrial Crops and Products. (in press)
Zhang, R.H., P. Yang, Z. Pan, T.D. Wolf, J.H. Turnbull. 2004. Treatment of Swine Wastewater with Biological Conversion, Filtration, and Reverse Osmosis - A Laboratory Study. Transactions of the ASAE. 47(1):243-250.
Li, X. and R.H. Zhang. 2004. Integrated Anaerobic and Aerobic Treatment of Dairy Wastewater with Sequencing Batch Reactors. TRANSACTIONS of the ASAE. 47(1):235-241.
Romano, R.T., R.H. Zhang and K.M. Hartman. 2004. Anaerobic Digestion of Onion Wastes Using a Continuous Two-Phase Anaerobic Solids Digestion System, Paper Presented at at ASAE/CSAE Annual International Meeting, August 1-4, 2004. Ottawa, Canada. ASAE Paper Number: 047070
Zhang, R.H. and Z. Zhang. 2002. Anaerobic Digestion of Vegetable Waste with an Anaerobic Phased Solids Digester System. Transactions of Chinese Society of Agricultural Engineering. 18(5):134-139.
Membership in Professional Societies
American Society of Agricultural and Biological Engineers
American Society of Women Engineers
Association of Overseas Chinese Agricultural, Biological and Food Engineers Gamma Sigma Delta
Alpha Epsilon
Courses Offered
EBS 135 - Bioenvironmental Engineering
EBS170A- Engineering Design and Professional Responsibilities
EBS170B – Engineering Projects: Design
EBS170C – Engineering Projects: Evaluation
EBS 200 - Research Methods in Biological Systems Engineering
EBS 245 - Waste Management for Biological Systems
ABT 121 - Animal Housing and Environmental Management
Research Support
United States Department of Agriculture
United States Department of Energy
California Energy Commission
California Air Resources Board
California Integrated Waste Management Board
Sacramento Municipal Utility District
Private Industry