Project Overview

Commodities

• Animal Products: dairy

Practices

• Animal Production: manure management

• Education and Training: extension

Solids and nutrients found in liquid manure pose challenges to manure handling processes and
cause environmental concern. Separating solids and nutrients from liquid manure is a critical step
in reducing manure handling costs, enabling better use of nutrients and water, controlling odor and
gas emissions from manure storage lagoons and manure irrigated lands, and reducing pollution
potential to ground and surface waters caused by manure, thus supporting the sustainability of the
dairy industry. This project will be the first to evaluate and compare centrifuge and disk filtration
separation technologies with a commonly used screen separation method to provide research-based
information to help dairy producers make informed decisions. The purpose of this project is to
demonstrate, evaluate, and encourage the widespread adoption of the centrifuge and disk filtration
solid/nutrient separation technologies, resulting in a more sustainable dairy industry. The approach
combines on-farm evaluation, lab tests, cost analysis, and extension activities. The project will
demonstrate the centrifuge and disk filtration effects on the capture of solids, nitrogen, and
phosphorous and on mitigating ammonia emissions. The cost effectiveness of each technology will
be analyzed to provide critical economic information for Idaho and western region dairy producers.
The expected outputs and outcomes include: 1) assessment of solids, nitrogen, and phosphorous
separation efficiencies; 2) assessment of ammonia emissions from both treated and untreated liquid
dairy manure; 3) analysis of costs associated with the demonstrated technologies; 4) field days and
producer workshops; 5) development of scholarly publications, educational materials and
technical manuals that could be adopted by Natural Resources Conservation Service (NRCS)
Idaho and Idaho State Department of Agriculture as Best Management Practices; and 6) increased
knowledge, well-informed producers, and increased adoption of the demonstrated technologies.

(1) Evaluate efficiencies on capturing solids, N and P from liquid dairy manure by three different
separation technologies (centrifuge, disk filtration, and inclined screen) under real farm
operation conditions. This evaluation and comparison will provide producers research-based
data for making informed decisions;
(2) Evaluate NH3 emissions from centrifuge, disk filtration, and inclined screen treated and
untreated liquid manure to document their effects on mitigating NH3 emissions;
(3) Analyze costs associated with the demonstrated technologies to provide economic information
to help producers make informed decisions;
(4) Develop scholarly publications and educational materials to encourage the widespread
adoption of the demonstrated technologies in Idaho and the western states;
(5) Deliver four field days during this project period to demonstrate the manure solid/nutrient
centrifuge and disk filtration separation technologies to familiar stakeholders with the
demonstrated technologies;
(6) Conduct in-service training for Idaho statewide extension personnel to increase extension
manpower;
(7) Hold three producer workshops to communicate the project results with dairy producers,
resulting in increased awareness of the demonstrated technologies among farmers;
(8) Develop two technical manuals covering the utilization of centrifuge and disk filtration
technologies, respectively that could be adopted by the Idaho Natural Resources Conservation
Service (NRCS), Idaho State Department of Agriculture (ISDA), and Idaho Department of
Environmental Quality (IDEQ) as Best Management Practices (BMPs).