On-farm evaluation and demonstration of advanced manure solidliquid separation technologies for a sustainable dairy industry in Idaho

Project Overview

Project Type: Research and Education
Funds awarded in 2018: $287,466.00
Projected End Date: 03/31/2022
Grant Recipient: University of Idaho
Region: Western
State: Idaho
Principal Investigator:
Dr. Lide Chen
University of Idaho

Information Products


  • Animal Products: dairy


  • Animal Production: manure management
  • Education and Training: extension

    Proposal abstract:

    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.

    Project objectives from proposal:

    (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
    (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).

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.