Project Number: 1265-12000-028-00
Project Type: Appropriated

Start Date: Apr 03, 2005
End Date: Apr 02, 2010

Objective:
Develop and evaluate algal systems for the treatment of dairy and swine manure effluents with respect to: a) capturing N and P from raw and anaerobically digested dairy manure effluents; b) utilization of the algal biomass as an organic fertilizer; and c) overall system nutrient uptake efficiency, operational costs, and potential returns of integrated farm-scale systems. Determine levels and biological effects of oxytetracycline and chlorotetracycline in manure from treated animals on biological treatment processes. Determine levels of antibiotic resistant bacteria in treated manures from animals treated with oxytetracycline and chlorotetracycline. Develop technology and management practices that improve anaerobic digestion of dairy and other animal manure by: a) increasing yield of methane gas; b) increasing energy efficiency of the conversion system; and c) reducing cost. Develop technology to increase the efficiency with which the methane is used to economically meet the energy needs of the farm.

Approach:
Laboratory and pilot-scale field studies will be used to evaluate treatment efficiency and cost of microalgal-based treatment technologies at different loading rates of raw and anaerobically digested manure effluents. Dried algal biomass from manure treatment will be tested in growth chamber studies to evaluate the value of the biomass as an organic fertilizer capable of meeting plant nutrient requirements. Laboratory-scale composting, soil incubation, and anaerobic digestion studies will be used to determine the fates of the antibiotics oxytetracycline, chlorotetracycline, and antibiotic-resistant bacteria in manures from therapeutically treated beef calves. Laboratory and pilot-scale field studies will be used to quantitate effects on methane yield of co-digesting dairy manure with agricultural and industrial by-products. Additional studies will focus on use of cold tolerant microbial consortia to improve the rate and yield of methane production during anaerobic digestion of dairy manure at 10-25 C.