S-1000
Regional Project
Animal
Manure and Waste Utilization, Treatment and Nuisance Avoidance for a Sustainable
Agriculture
2003
Station Reports
a. Reporting Scientists
and Location
Ruihong Zhang
Biological and Agricultural Engineering Department
University of California, Davis
Davis, CA 95616
Phone: (530)750-2124
Email: rhzhang@ucdavis.edu b. Progress to Date by
Objective and Task
Objective 2. Develop, evaluate, and refine physical, chemical and biological
treatment processes in engineered and natural systems for management of manures
and other wastes.
Task 1. Develop and evaluate innovative applications of engineered biological
treatment processes to stabilize waste, reduce odor, and manage nutrients.
A commercial dairy wastewater management system was evaluated for solids
separation and degradation. The characteristics of flush water and collected
manure were determined. In addition, the performance of the solid-liquid
separator and the impact of low rate aeration in the lagoons on solids degradation
and odor reduction were evaluated. The results of this study will be presented
at Ninth International Symposium of Animal, Agricultural and Food Processing
Wastes, October 11-14, 2003, Raleigh, North Carolina. The symposium paper
is attached for information. A summary of the research findings is as follows.
The characteristics of recycled wastewater for flushing was found to be very
consistent over a five-month period with the standard deviations of total
solids (TS) and volatile solids (VS) being 6.4% and 7.1% of the mean values,
respectively. The characteristics of fresh manure collected in the flushing
water were less consistent with the standard deviations of TS and VS being
26.2% and 23.6% of the mean values, respectively. Solid removal efficiency
of the stationery screen separator was 26.9%, 33.9%, 36.8% and 41.5%, for
TS, VS, SS, and VSS, respectively, with the standard deviations being 17.2-25.8%
of the mean values. The low rate aeration of the lagoons did result in less
solids build-up and reduced the odor threshold by 20 to 40%, but it had an
insignificant impact on the existing sludge in the lagoons. More intense
aeration is needed in order to cause significant degradation of solids in
the lagoons.
c. Usefulness of Findings and Impacts
This research measured the flow rate and characteristics of the wastewater
collected on a typical flushed dairy operation in California. The results
are very useful for engineers and dairy producers to design wastewater management
systems on dairies. The research also evaluated the performance of a mechanical
solid-liquid separator and a low-rate aeration system for lagoons and results
will be very useful for further developing effective wastewater treatment
systems on dairies to meet the objectives of reducing the solid loading and
odor generation in anaerobic lagoons.
d. Planned work for the next year
Develop engineering designs and cost evaluations
for integrated wastewater treatment systems for dairies, which include solid-liquid
separation, anaerobic digestion, and aerobic treatment.
Study anaerobic digestion (thermophilic and mesophilic)
of cattle feedlot manure and develop engineering designs of manure treatment
systems for Cattle feedlot.
e. Publications
Zhang, R.H., P. Yang, Z. Pan, T.D. Wolf, J.H. Turnbull. 2003. Treatment
of Swine Wastewater with Biological Conversion, Filtration, and Reverse Osmosis
- A Laboratory Study. Transactions of the ASAE. In Press.
Zhang, R.H., P. Yang, C. Collar and L. Ham. 2003. Treatment of flushed dairy
manure by solid-liquid separation and lagoon aeration. Paper to be presented
at The Ninth International Symposium on Animal, Agricultural, and Food Processing
Wastes (ISAAFPW). October 12-15, 2003. Raleigh, NC.
Li, X. and R.H. Zhang. 2003. Integrated Anaerobic and Aerobic Treatment of
Dairy Wastewater with Sequencing Batch Reactors. TRANSACTIONS of the
ASAE. In Press.
Li, X. and R.H. Zhang. 2002. Aerobic treatment of dairy wastewater
with sequencing batch reactor systems. Bioprocess and Biosystem Engineering.
25:103-109.