w2w15 – Page 12 – Livestock and Poultry Environmental Learning Community

March 5, 2019March 20, 2019

The Dairy Manure Biorefinery

Why Consider Additional Technologies with Anaerobic Digestion?

Some dairy farms have experimented with “add-on” technologies to enhance the value of the products generated from anaerobic digesters to improve economics and address other environmental and management concerns. This effort has intensified in recent years, as prices paid for electricity continue to fall. This trend is making it more difficult to justify the installation of new digesters or maintain active anaerobic digestion (AD) projects based on electricity sales alone.

What did we do?

Based on ten years of research and extension within the field of dairy digesters, we are proposing that the concept of a dairy manure biorefinery can be useful to focus ongoing research and commercialization efforts (Figure 1). A biorefinery integrates a core biomass conversion process (in this case, AD, converting manure and in many cases other organic substrates) with additional downstream technologies. These combined technologies generate multiple value-added products including fuels, electricity, chemicals, and other products (NREL, 2009). Most add-on technologies relevant to dairy facilities have been modified from technologies used in the wastewater treatment and oil and gas industries.

What have we learned?

Ongoing research and commercialization efforts by our team and others aim to:

Adapt technologies to fit the economic and other constraints of dairy digesters.
Increase efficiency and reduce costs by maximizing the complimentary nature of technologies (e.g. waste heat from one process is used in another process).

Specific add-on technologies that are continuing to evolve within the biorefinery context include:

Biogas Upgrading to remove impurities from biogas (primarily carbon dioxide, hydrogen sulfide, and water vapor).

Output: Purified biogas that can be used as a transportation fuel (e.g. liquefied natural gas) or injected directly into natural gas piplelines.

Additional social and economic benefits: Renewable fuel can reduce demand for fossil fuels, and can often receive economic credits (e.g. renewable identification numbers, low carbon fuel standard)

Fiber Upgrading to process the fiber that is removed from AD effluent.

Output: Upgraded fiber can be sold as a higher-value soil amendment in the horticultural industry

Additional social and economic benefits: Fiber can replace use of non-renewable resource (peat moss) by horticultural industry

Nutrient Recovery to strip nitrogen (N) and phosphorus (P) from anaerobic digester effluent.

Outputs: Soil amendment products that can be sold offsite where nutrients are needed

Additional social and economic benefits: Reductions in N and P applied to nearby fields, and reduced effluent hauling distances/costs for land application due to lower nutrient concentration in effluent

Water Recovery to generate “recycled” water using advanced technologies

Output: Water that can be used for animal drinking, or as dilution water for the AD facility

Additional social and economic benefits: Reduces consumption of fresh water, a limited resource, and reduces costs for land-application of AD effluent

Overall Potential Impact. Improving economics and addressing other critical issues for dairy producers (e.g. nutrient issues) has the potential to advance farm-based AD adoption significantly beyond its current 244 farms. It has been estimated that a mature bio-refinery industry based on AD on large U.S. dairy farms could create an estimated bio-economy of nearly $3 billion that complements the production of milk and dairy products (ICUSD, 2013).

Figure 1. Stepwise depiction of the process

Figure 2. Total likely value added by most likely scenario

Authors

Georgine Yorgey (presenting author)^a, Craig Frear^b, Nick Kennedy^a, Chad Kruger^a, Jingwei Ma^b, and Tara Zimmerman^a

^aCenter for Sustaining Agriculture and Natural Resources, Washington State University

^bDepartment of Biological Systems Engineering, Washington State University

Future Plans

An extension document describing this concept and the add-on technologies in additional detail is being prepared. This document is part of a series of extension documents on Dairy AD Systems, being prepared by the authors and other colleagues at Washington State University. In addition, ongoing work and collaborations by our team are seeking to investigate, evaluate, and improve individual technologies and the linkages amongst them.

Additional Information

ICUSD, 2013. National market value for anaerobic digestion products. Report to Innovation Center for US Dairy, August 2013.

Acknowledgements

This research was supported by USDA National Institute of Food and Agriculture, contract #2012-6800219814; and Biomass Research Funds from the Washington State University Agricultural Research Center.

The authors are solely responsible for the content of these proceedings. The technical information does not necessarily reflect the official position of the sponsoring agencies or institutions represented by planning committee members, and inclusion and distribution herein does not constitute an endorsement of views expressed by the same. Printed materials included herein are not refereed publications. Citations should appear as follows. EXAMPLE: Authors. 2015. Title of presentation. Waste to Worth: Spreading Science and Solutions. Seattle, WA. March 31-April 3, 2015. URL of this page. Accessed on: today’s date.

March 5, 2019March 20, 2019

Fate of Manure Nitrogen Applied for Grass Silage Production

Purpose

Previous research conducted in western Washington State has demonstrated that when manure N is applied at rates greater than needed for grass uptake, excess N in soil in the form of nitrate-N can leach to shallow groundwater during the months of high rainfall. In a prior study, it was evident that tillage and reseeding of the cropland was a contributor to loss of nitrate–N from soil to underlying groundwater. The objective of this study was to characterize the effect of re-seeding of cropland using minimum tillage and conventional tillage methods on crop uptake of nitrogen, soil nitrate-N concentration, nitrate concentration in shallow ground water underlying the field, and the relationships between these matrices.

What did we do?

A two- year study was initiated in 2009 to study the fate and transport of nitrogen from dairy manure when applied to cropland that was reseeded to grass for silage production. One-half of a 22- acre grass field was prepared with conventional tillage, and one-half was prepared with minimum tillage in May of 2009. In 2009, after the grass was reseeded, the conventional till grass was harvested 2 times, and the minimum till grass was harvested 3 times. Due to poor stand establishment, the minimum till area received minimum till treatment again in 2010. In 2010, the conventional till grass was harvested 4 times, and the minimum till grass was harvested twice.

What we have learned?

Total nitrogen harvested for minimum till and conventional till respectively, were: 310 and 298 lbs/acre (2009), and 425 and 477 lbs/acre (2010). Total nitrogen applied for minimum till and conventional till, respectively, were: 523 and 440 lbs/acre (2009), and 697 and 697 lbs/acre (2010). Soil nitrate-N for the minimum till plot remained below 30 ppm in 2009 except on one occasion. Soil nitrate for the minimum till plot was observed to increase to 40 and 60 ppm in 2010. Soil nitrate-N for the conventional till plot increased to 60 ppm in 2009, and 35 ppm in 2010. There was no evidence of a difference in groundwater nitrate-N due to the type of tillage treatment. Groundwater nitrate-N concentrations on the whole were higher in monitoring wells after both tillage methods were applied. Results from this case study indicated that the type of tillage had an impact on the timing of increases in soil nitrate. However, variability in denitrification conditions in monitoring wells did not allow a determination of whether one method had more of an impact on groundwater nitrate than the other. (See Figures 1 and 2.)

Figure 1. Soil nitrate concentrations during the study period.

Figure 2. Average shallow ground water nitrate concentrations during the study period. Green arrows indicates tillage events.

Authors

Joe Harrison*, Professor and Nutrient Management Specialist, Washington State University, jhharrison@wsu.edu

Barb Carey, Environmental Assessment Program Washington Department of Ecology; and Lynn VanWieringen, Research Associate, Washington State University.

*presenter

Future plans

A study has been proposed to characterize the effect of converting the grass field to corn silage and determine uptake of nitrogen, soil nitrate-N concentrations, nitrate concentrations in shallow ground water underlying the field, and the relationships between these matrices.

Additional information

Joe Harrison jhharrison@wsu.edu Joe Harrison, jhharrison, 253-445-4638, Washington State University

March 5, 2019May 7, 2019

Youth A. Greenhouse Gas Educational Lab Materials via Pork Production Scenarios

Why Examine Greenhouse Gases Relative to Pig Farm Decisions?

1. Educate students within the state of Arkansas about the various management systems intrinsic to swine production operations within their state.

2. Provide students insight into the management obstacles that Arkansas swine producers are challenged with through balancing Carbon footprints, economic resources, natural resources, and legal compliance with production profitability

What did we do?

This project presents a dynamic lab activity with emphasis on introductory level subject matter about Arkansas swine production systems and the related greenhouse gas emissions. The activity materials were crafted into two complementary products for practicality. The first product is a compilation of swine production reference materials, including; terminology, layman definitions of common Arkansas swine management strategies, and the basic dynamics of common greenhouse gasses (CO2, N2O, CH4) as they relate to this activities scope of swine production. The reference material serves as both an introduction to basic ideas and practices native to swine production and GHGs, as well as a guide which aids the students in completion of the second product (lab activity).

The second product is a scenario based critical thinking exercise, implemented from a manipulative decision-tree platform. Flashcards are used to represent three specific swine management systems using a three tier hierarchy. This hierarchy is distinguished by the allocation of Categories, Components, and Options. The “Categories” are the designated ranking class and will represent three major swine production management systems: Housing Management, Manure Management, and Feed Management. The “Components” are the first sub-order class, and are used to represent various functions/considerations that comprise each “Category” of production system. The “Options” class holds the lowest position within the hierarchy and represents the different configurations/settings for the individual “Components”. Throughout the context of this exercise the students will act as virtual consultants hired by a producer to design the three management systems (via the flashcards) to “best match” the producer’s expressed concerns and desired specifications, as defined by a supplied catalogue of unique scenarios.

What have we learned?

(Classroom implementation of the materials is pending)

Future Plans

Implementation of the materials via:Arkansas Farm Bureau’s Ag-In-The-Classroom program. We are also exploring opportunities to blend the materials into 4-H curriculums, and possibly have the materials available for adoption by high school educators within Arkansas.

Authors

Szymanski “Rick” Fields II, Program Associate, Biological and Agricultural Engineering, University of Arkansas Division of Agriculture Extension rfields@uaex.edu

Karl VanDevender, Professor-Engineer, Biological and Agricultural Engineering, University of Arkansas Division of Agriculture Extension

Additional information

http://lpelc.org/reaching-the-next-generation-through-fun-and-interactive-activities/

Acknowledgements

Dr. Jennie Popp, University of Arkansas

Dr. Rick Ulrich, University of Arkansas

Donna VanDevender

March 5, 2019March 6, 2019

An NE-1441 Project: Proposed Methodologies for Administering a Multi-State Environmental Best Management Practices Survey of Equine Properties

*Purpose

Several states have reported that equine are the fastest growing segment of the livestock industry. Nationwide, equine has increased by 77% since 1997; and it is reported there are approximately 9.5 million horses in the United States (AHC, 2005). Proper management of equine operations requires the adoption of Best Management Practices (BMPs) to balance nutrient production and prevent erosion. Government agencies are concerned about non-point sources of water pollution and have focused on agriculture, including equine operations, as a major contributor to water quality issues. Many states’ laws have regulated equine farms, requiring farm managers to incorporate BMPs. The objectives of this proposed national (multi-state) survey are to quantify and assess the use of the equine industry’s BMPs in pasture management, erosion control and to examine potential environmental impacts. Few state studies have investigated horse BMPs in the U.S, and more research is needed to assess the effect of horse farm management on U.S. water quality. Knowledge of the current scope and nature of equine industry management practices are important when developing regulations, laws, and educational programs to enhance the stewardship and govern land management on equine operations.

What did we do?

The methodology to assess horse property manager/owner practices consists of gathering a minimum of 150-2,000 names and email addresses of horse owners/farm managers from the 15 states involved in the NE-1441 project. Some of the N. E. states have fewer equine operations. An email containing survey information and a link to the 40 question online survey will be sent to horse farm managers in 2016. Three follow-up reminders will be sent to non-responding addresses. It is hoped to have a 40% response rate. Data will analyzed using SPSS 16.0 (SPSS Inc., Chicago, IL) for descriptive statistics, determining response frequencies and percentages.

The Questionnaire Instrument will include the following areas:

Part I General: Involved in the horse industry? Are you the owner or manager of a horse operation? If No, then you are finished taking the survey. Business or Hobby?

Part II Demographics: Location, State, County, Survey participants gender, age, Size of farm total acreage, Confinement areas, Pasture areas, primary and 2nd use of operation, Highest average number of horses on property? On average, how many hours per day do your horses spend grazing pastures by seasons?

Part III Horse Pasture Management Rotational Grazing, unlimited access,Pasture Management Plan, Agricultural Erosion and Sedimentation Plan weed control and type, mowing, resting pastures,Sacrifice lots, pasture topography, surface water, Sheds and barns,divert runoff, roof gutters.

Part IV: Horse Pasture Applications and/or Evaluation: Line, Fertilizer, Herbicide use, Seeding practices, Lime, Soil testing.

Part V: Horse Manure Management: Nutrient Management Plan, primary manure management, collection, storage, uses, removal.

Part VI: Conclusion: What are your limitations in altering the management of your horse operation? What information resources do you use for your equine farm operations?

What have we learned?

The questions for an equine related APHIS/USDA animal agriculture survey need to be more specific to the activities and needs of the horse industry. Whereas most animal agriculture operations do not deal directly with the general public as a necessary component of their business plan, the horse industry depends on active and engaged clientele. If we are able to gather national data through a single effort survey, the resulting information could be compared and sorted in a consistent and statistically reliable manner, allowing educational materials and opportunities to be tailored to area or regional needs.

Future Plans

A survey will be conducted by the NE-1441 (a northeast regional Hatch research group focusing on environmental impacts of equine operations) participating states to determine the use of the following best management practices: managed storage area, composted manure storage, stream crossings, buffers and vegetative filter strips, heavy use pads and sacrifice areas, soil testing, and fertility management on fields receiving manure. Develop means of determining the impact of equine outreach programs, more specifically determination of BMP adoption rate.This will allow us to chart progress among producers who use extension services and/or implement BMPs with the assistance of extension or other service providers such as NRCS, state departments of agriculture, and etc. We will work with social scientists to determine adoption rates, what the reasons for resistance to adoption are, and how to develop programs to overcome this resistance.

Corresponding author, title, and affiliation

Betsy Greene, Professor/Equine Extension Specialist, University of Vermont

Corresponding author email

betsy.greene@uvm.edu

Other authors

Ann Swinker, Extension, Pennsylvania State University Amy Burk, Extension, University of Maryland Rebecca Bott, Extension, South Dakota State University Carey Williams, Extension, Rutgers, State University of New Jersey

Additional information

Westendorf, M. L., T. Joshua, S. J. Komar, C. Williams, and R. Govindasamy. 2010. Manure Management Practices on New Jersey Equine Farms. Prof. Anim. Sci. 26:123-129.

Swinker, A., S. Worobey, H. McKernan, R. Meinen, D. Kniffen, D. Foulk, M. Hall, J. Weld, F. Schneider, A. Burk, M. Brubaker, 2013, Profile of the Equine Industry’s Environmental, Best Management Practices and Variations in Pennsylvania, J. of NACAA. 6:1, 2158-9429.

Fiorellino, N.M., K.M. Wilson, and A.O. Burk. 2013. Characterizing the use of environmentally friendly pasture management practices by horse farm operators in Maryland. J. Soil Water Conserv. 68:34-40.

Acknowledgements

The State University Extension Equine Specialists that make up the NE-1441: Environmental Impacts of Equine Operations, Multi-State Program. USDA.

March 5, 2019July 15, 2020

Case Study of Contaminated Compost: Collaborations Between Vermont Extension and the Agency of Agriculture to Mitigate Damage Due to Persistent Herbicide Residues

Why Study Herbicide Contamination of Compost?

Picloram, clopyralid, aminopyralid and aminocyclopyrochlor are broadleaf herbicides commonly used in pastures due to effectiveness in controlling undesirable plants and the very low toxicity for animals and fish. In fact, some of these herbicides do not require animal removal post application. The grazing animals can ingest treated leaves with no ill health effects, but may pass the herbicides through to the manure. Also see: Composting Livestock or Poultry Manure

When a complaint driven problem of damaged tomatoes and other garden crops in Vermont was traced back to a single compost provider in Chittenden County in Vermont, a series of actions and reactions commenced. Complaints were fielded and investigated by personnel from the Vermont Agency of Agriculture, Food and Markets (VT-AG) and the University of Vermont Extension (UVM-EXT). The compost provider sent samples of various components of the compost to a single laboratory and received positive results for persistent herbicides in sources of equine bedding/manure components. Subsequent interviews by the facility manager in both print and television media seemed to cast blame on Vermont equine operations for ruining Vermont gardens. Coincidentally, the composter had recently changed compost-processing methods. Initial samples sent to a separate laboratory did not support the composter’s laboratory results. Samples of feed, manure, shavings, and many other components which were shipped to several laboratories by VT-AG, resulted in extremely inconsistent and/or contradictory data between laboratories running the exact same samples.

What did we do?

Several processes were underway by several agencies in a coordinated and collaborative effort to resolve and mitigate the herbicide issues:

• Vermont Agency of Agriculture, Food and Markets was receiving and investigating complaints.

• University of Vermont Extension plant biology personnel were identifying, documenting, and sampling affected plants, as well as counseling gardeners.

• University of Vermont equine extension worked with horse owners and media to mitigate unsubstantiated claims of “horses poisoning garden plants”.

• A more thorough investigation by VT-AG involved collection of raw samples (feed, hay, shavings, manure) from 15 horse farms who utilized the compost facility to dispose of manure and bedding.

• The VT Secretary of Agriculture and the VT-AG Agri-chemical Management Section Chief were brought together with equine and compost experts attending the NE-1041 Equine Environmental Extension Research group annual meeting hosted by UVM equine extension.

• VT-AG worked with herbicide manufacturers to use high quality testing equipment and procedures to gather consistent data from samples.

What have we learned?

More extensive details of this particular case have been published in the Journal of NACAA (http://www.nacaa.com/journal/index.php?jid=201).

• The levels of persistent herbicides were low enough that they were below the acceptable limits for water, yet they still harmed sensitive garden plants.

• Nationally and locally manufactured grains tested positive for persistent herbicides; most likely due to the individual components being treated within legal limits during field production.

• Many of the laboratories were unable to provide accurate or consistent results when testing for the persistent herbicides.

• Discussions between the NE-1041 group and VT-AG resulted in a fruitful exchange of information, as well as development and delivery of pertinent information for the general public and County Agricultural Agents.

Future Plans

Several proactive activities have already been initiated and/or completed. A peer reviewed case study on all aspects of the contaminated compost has been published in the Journal of NACAA; and two episodes of Vermont’s Agricultural television show (Across the Fence) were created to educate and update the general public on the situation. A Vermont compost working group has been assembled and set goals to create potential educational materials including a horse owner pamphlet (in final editing phase), a farmer/livestock pamphlet, and press releases for the public education on challenges with persistent herbicides. The VT-AG website has a Compost FAQs page addressing the most common questions associated with compost and herbicides.

Authors

Betsy Greene, Professor/Extension Equine Specialist, University of Vermont Betsy.Greene@uvm.edu

Carey Giguere, Agrichemical Management,Vermont Agency of Agriculture

Rebecca. Bott, Extension, South Dakota State University

Krishona. Martinson, Extension, University of Minnesota

Ann Swinker, Extension, Penn State University

Additional information

• Greene, E.A., R.C. Bott, C. Giguere, K.L. Martinson, and A.W. Swinker. 2013. “Vermont Horses vs. Twisted Tomatoes: A Compost Case Study. J of NACAA. 6:1 (http://www.nacaa.com/journal/index.php?jid=201)

• Vermont Agency of Agriculture, Food and Markets Compost FAQ’s: http://agriculture.vermont.gov/node/696

• Davis, J. Dept. of Horticultural Science, NC State University. 2010. Herbicides in Manure: How Does It Get there and why Should I Care?, Proceedings 8th Annual Mid-Atlantic Nutrition Conference, Timonium, MD. pp 155-160.

• Across the Fence Television Show: An Update on Green Mountain Compost Contamination and Testing-Greene/ Gigliuere (9/14/12)

• Across the Fence Television Show: Information from NE 1041 Meetings and National Equine Specialists-Greene (9/17/12)

• Article from Minnesota Extension explaining the problem in hay and how to avoid it. The article is devoted to “ditch hay”, but the information is relevant to all hay. https://extension.umn.edu/horse-nutrition/managing-herbicides-ditch-forages

• Washington State University Web site on clopyralid carryover includes pictures of affected vegetables, research results, and the bioassay protocol http://www.puyallup.wsu.edu/soilmgmt/Clopyralid.htm

• Dow Agrosciences United Kingdom website with information on aminopyralid: http://www.manurematters.co.uk/

• CDMS Agro-chemical database with access to all the herbicide labels: http://www.cdms.net/LabelsMsds/LMDefault.aspx?t

Acknowledgements

The State University Extension Equine Specialists that make up the NE-1441: Environmental Impacts of Equine Operations, Multi-State Program. USDA.

March 5, 2019May 7, 2019

Composting and the Benefits: Achieving Practice Change through Education to Reduce Nutrient Loads and Increase Adoption of Best Management Practices

Purpose

Florida houses roughly 500,000 horses and is also home to 700 freshwater springs; Marion County is, “Horse Capital of the World” and houses two first magnitude springs and each is currently in a restoration plan with the Florida Department Environmental Protection Agency (FDEP). The Florida Department of Agriculture and Consumer Services (FDACS) equine Best Management Practices (BMP) Manual recommends composting as an excellent manure management option.

Composting is a controlled biological process that decomposes and heats up organic material to produce a biologically stable humus, which can then be used as a rich soil amendment. Composting provides protection to the ground and surface waters by preventing excess nutrients from being leached out and running-off into the waters. It destroys up to 90% of weed seeds contained in manure and kills parasite eggs and pathogens. Additionally, the organic matter/compost helps prevent and control soil erosion and can improve both soil quality and productivity.

What did we do?

Individual and group programming has been developed to educate farm owners and managers about the benefits derived from composting horse manure/spent bedding. Since 2007, Over 800 farms have been seen in the county. In 2013 alone, 132 participants were involved in individual farm consultations or farm revisits, group presentations and composting workshops. Education was provided and supplemental materials were developed for clientele about composting manure, compost bin construction and composting’s soil-improvement capabilities. Compost Countryside

What have we learned?

Pre and post-test results showed a 62% (82 of 132 total participants) knowledge gain from information taught. A total of 71% (n=12 of 17 farm revisit consultations) of farms revisited improved and adopted recommended manure handling practices after receiving education. Additionally, seven farms and facilities have begun cost-share planning with Southwest Florida Water Management District (SWFWMD) for compost bin construction. Results/impacts show improved management practices and a greater understanding of BMPs, allowing for a decrease in nutrient levels to the ground and surface waters. Pictures show sample bins which were constructed as a result of individual and group programming.

Future Plans

Continued group and individual programming needs to be continued, in partnership with trade journal articles being written about manure management, protection of the ground and surface waters and the benefits derived from composting manure/bedding. Cost-share dollars, coming from state organizations, will further incentivize farms to construct and use compost facilities as part of a regular manure management plan.

Author

Jamie Cohen, Farm Outreach Coordinator, UF/IFAS Extension Marion County jamiecohen@ufl.edu

Additional information

My eXtension.org Manure Management Strategies Webcast: https://connect.msu.edu/p8yko9zhhoq/?launcher=false&fcsContent=true&pbMode=normal

eXtension.org –Manure Management page: https://lpelc.org/horse-manure-management/

A Guide to Composting Horse Manure: www.whatcom.wsu.edu/ag/compost/horsecompost.htm

March 5, 2019July 15, 2020

Economical Anaerobic Digestion of CAFO Animal Waste

Purpose

The application of manure on croplands is increasingly under regulatory scrutiny, especially from impaired watersheds. The challenge facing many small farms is to find cost-effective and innovative solutions for manure reuse whilst responding to environmental, regulatory and public concerns. One option is to install an anaerobic digester (AD) in which microorganisms break down biodegradable material in the absence of oxygen. However, not all farmers are financially able to install an AD but do need the AD’s benefits to keep their livestock operation sustainable. This paper discusses a novel, cost effective and patented manure treatment system which can reduce the volume of manure for field application (see Figure 1). Earthmentor N2RTS Schematic

What did we do?

The EarthMentor® Natural Nutrient Reclamation and Treatment System (EMS), uses a combination of innovative sand separation technology (if necessary) and anaerobic treatment to concentrate manure nutrients into solid phases and treat approximately 70% of manure liquids into a product which can be applied to active cropland as low-nutrient liquid using irrigation methods. The primary economic advantage of using an EMS to treat livestock manure prior to land application is lower total manure disposal costs. The total manure handling costs are reduced because up to 75 % of the original manure volume can be handled as low-nutrient value irrigation quality liquid in bulk instead of hauling it by tanker for land application. This fact alone reduces total manure handling costs by over 50 %. Other tangible benefits of using an EMS include low odor, minimized environmental risks, and greater flexibility in proper land application of the treated manure. It can be installed at farms with as few as 250 cows. Depending on farm size, operators can realize a return on investment in as little as three years. Compared to a traditional AD installed to generate biogas the EMS is simple to operate, requires less energy, requires no chemicals or substrates to treat the waste, and reduces manure disposal costs.

The EMS involves six major steps: 1) collection of raw manure and transport to the processing center, 2) sand bedding is separated from the manure stream, 3) coarse manure components are removed from the liquid manure stream, 4) additional settling of the fine manure solids and sand particles occurs in a settling basin to a concentration of 8 to 10 percent solids, 5) AD treatment of the liquid manure and dissolved solids occurs in anaerobic treatment lagoon (ATL), and 6) The ATL effluent is stored in a Storage Pond for eventual discharge to active growing crops; additional natural treatment of the liquid manure occurs while in the Storage Pond.

All settling basins and ATL lagoon must meet state guidelines, such as Natural Resource Conservation Service technical guidelines or state requirements for waste storage facilities.

The ALT of the EMS system has a smaller footprint compared to traditional ALTs (primarily use in the south and western United States) because the majority of the nutrient-rich semi-solids are removed from the manure before discharge to the ATL. Due to this major operational change the EMS is economical to install and operate even in the northern climates of the United States where many of the top producing dairy states are located. While many facilities separate solids before land application, the EMS is different because is adds the AD step which converts the manure into a low-nutrient liquid capable of irrigation-style land disposal. The method of solid separation can be as simple as a sloped screen followed by additional gravity separation as described in Step 4 above. The EMS ATL must be sized to account for reduced biodegradation during the colder weather. The EMS has successfully operated at multiple swine facilities and several Midwestern dairy farms.

If there is sufficient land near the farmstead, the EMS can be installed at existing dairies with minimum difficulty since the treatment system works equally well with multiple bedding materials and varying manure collection methods. Another benefit of the EMS is that is allows application on fields that may be high in phosphorus since much of the phosphorus will be stored in the accumulating ATL sludge. For dairies bedding with sand, a patented sand removal system can be provided that relies on a decanting method of sand separation. Once the sand is removed, it can be reused in the barn.

What have we learned?

Typical Cost Savings for Manure Application Using EMS
Component	Disposal Method	Conventional Manure Handling		EarthMentor^® Treatment System Handling
Liquid Manure	Land Application	100%	$0.02/gallon	0%	$0
Separated Solids	Land Application	0%	$0	10%	$0.016/gallon ($4/ton equiv.)
Heavy Slurry	Land Application	0%	$0	20%	$0.02/gallon
Treated Wastewater	Center Pivot over Crop	0%	$0	70%	$0.002/gallon
Combined Cost		100%	$0.02/gallon	100%	$0.007/gallon (weighted average of all components)

Using financial data from 2010 for a 2,000-cow Michigan dairy, it was estimated that the cost to handle manure using an EMS is reduced from $0.02/gallon to $0.007/gallon. The cost saving using the EMS is based on the assumption that the average dairy cow produces nearly 25 gallons/day of manure, including wastewater but excludes bedding since farms used different types and volumes of bedding for their dry and lactating cows. Based on the financial analysis, installation of an EMS benefits the farm’s economic sustainability while providing other benefits including reduced environment risk associated with manure land application.

Far beyond the obvious cost savings associated with the EMS installation, a livestock producer will realize many other benefits. A partial list is provided below:

This practical and manageable manure treatment system requires little or no additional farm labor commitments yet greatly reduces overhead expenditures to keep the farm sustainable and competitive,
All manure is treated prior to land application (environmentally sound),
The more consistent high solids slurry can be precisely applied to fields with the greatest need as opposed to the highly variable manure nutrient concentrations recovered from a traditional manure pond,
Minimizes the environmental risks (ecologically viable) and farm nuisance potential,
The window of opportunity for manure application is extended to over 200 days instead of being limited to spring and fall applications for typical liquid manure,
Can provide a safe unlimited recycled bedding source for cattle, if so desired, by the dairy owner,
Permits farmer to follow BMPs for soil conservation,
Permits farmer to follow timing, rate, source, and place for fertilizer/crop nutrient applications,
Benefits the non-farm neighbors and community through reduced nuisance odors, and
Continues using the farm’s manure as a soil amendment for crop production, the most efficient use known.

Future Plans

The immediate future plans for EMS is to target small livestock producers, especially those within impaired watersheds. Since many ADs need a substrate material imported from outside the farm to be economically sustainable, the EMS is ideal for those farms that want to be good neighbors with reduced farm air emissions, need greater convenience in manure management, and desire to maximize the real cash value of their manure.

As the EMS adapts well to any bedding material, by investing time and dedicating property for the ATL any size operation can begin to treat their manure prior to land application and reduce their overall cost for manure management.

In addition to small farms we envision four possible adaptations of EMS; these examples are provided to show the transferability of this technology to farms desiring various outcomes from an EMS:

Installation of an Energy-Generating AD – if a farm wishes to generate energy using a traditional AD, it would be installed prior to the EMS system whereby the AD digestate discharges into the settling ponds. Since the residence time of a traditional AD is measured in days, there is a great deal of additional treatment that can occur so that the cost savings for land application can still be realized.
Use manure solids for other uses besides land application – if the livestock producer decides to bed their cattle on manure solids or to compost the manure solids for sale off-farm to landscapers or bag and sell direction from the farm then the solids from the SS can be further treated with a screw press or roller then composting by various means.
Greenhouse gas capture and sale of carbon credits – a geosynthetic liner cover can be added to the ATL and all captured gases burned through a flare. However, it should be noted that by removing a significant amount of high organic solids during the initial fiber solids separation step, much less organic material is subject to organic degradation into methane gas.
Greenhouse gas capture and burning of the gases – to generate electricity or heat water (typically for on-farm use or export to an adjoining business, such as a greenhouse).

One future issue to resolve includes educating state governments on the benefits of installing an EMS, especially for those farms that may be under a Consent Order or other regulatory actions or those farms that may need to implement a manure treatment system to mitigate odors from the livestock operation. The duration to install an EMS and get it operational is much shorter than the lead time to design and install a traditional AD so the EMS can help when farms need to implement changes quickly. A second issue to overcome is to properly educate producers on the benefits of EMS and differences between traditional ADs. Swine, beef, and dairy producers who already have a farm irrigation system will have a lower capital investment to begin achieving the reduced manure management costs referenced above.

Author

Matthew J. Germane, P.E., President at Germane Environmental Consulting, LLC MGermane@GECEnvironmental.net

Additional information

https://www.gecenvironmental.com, Envirolytic Technologies, LLC

Acknowledgements

Acknowledgements to Envirolytic Technologies, LLC, Greenville, OH manufacturer of the Earthmentor® N2RTS system and RAM Technologies, LLC, manufacturer of the sand separation equipment used in the EMS for their assistance in providing the laboratory data used in this paper.

March 5, 2019July 6, 2020

Evaluation of a Continuously-Mixed Farm-Based Anaerobic Co-Digestion System Following the U.S. EPA Protocol for Quantifying and Reporting on the Performance of Anaerobic Digestion Systems for Livestock Manures – Final Project Results

This paper compliments another paper proposed for this conference “Lifecycle analysis of greenhouse gas (GHG) emissions from a New York State dairy farm anaerobically co-digesting manure and food waste.”

Purpose

New York State’s largest manure-based anaerobic co-digestion facility was evaluated continuously for a 2-year period following the U.S. EPA Protocol for quantifying and reporting on the performance of anaerobic digestion systems for livestock manures. Overall, we assessed and determined the system’s performance with respect to the: 1) conversion of biomass to biogas, 2) conversion of biogas to useful energy, and 3) system’s economics. The information developed by this project can be used to compare performance information developed from other manure-based anaerobic digestion systems. Related: Treatment Technologies for Livestock Manure

What did we do?

After initial system evaluation and monitoring plan development, the farm was visited monthly for 24 months to collect data. In addition to the digester influent and effluent samples taken during each monthly sampling date, on-site measurements were taken and data were manually recorded from equipment and plant logs. A particularly important log, were the imported feedstocks brought on-site for inclusion to the AD. This log recorded the date and time feedstock was delivered, the type of feedstock, and the volume delivered. The specific data collected/measured are shown in Table 1.

Table 1. Data collected/measured on-site at each sampling date.

Item
1. Date and time of readings
2. Methane (CH4), Carbon dioxide (CO2), Oxygen (O2), and Hydrogen sulfide (H2S) concentrations in biogas after digester
3. CH4, CO2, O2, and H2S concentrations in biogas after bio-scrubber
4. Engine-generator set run time
5. Cumulative electricity purchased and sold
6. Daily animal populations since previous sampling event
7. Logs of imported feedstocks
8. Problems occurred during period

Further, data (Table 2) from the system’s supervisory, control, and data acquisition (SCADA) unit were downloaded, compiled and analyzed for each period. SCADA data were generated from an array of sensors and meters originally installed by the company that designed and built the digester, i.e., Bigadan A/S.

Table 2. Data obtained from the SCADA system for each period.

Parameter
1. Total influent to pasteurization
2. Food waste to pasteurization
3. Manure to pasteurization
4. Biomass from pasteurization to digester
5. Effluent digester to storage tank
6. Biogas production digester
7. Biogas to generator
8. Generator electrical energy output
9. Generator thermal energy recovered
10. Digester vessel upper temperature
11. Digester vessel lower temperature

Overall, digester influent and effluent samples were collected with the goal of obtaining representative samples. To do this, grab samples were collected directly from both the digester influent and effluent lines over a period of approximately 30 min during a pumping sequence, to develop a 5-gallon composite, master-sample. The entire volume of this sample was then agitated using a paint mixer powered by a portable electric drill until visibly determined to be homogenized. A 1-liter composite sample was immediately taken and stored on ice, and subsequently frozen before being sent for laboratory analysis. Samples were taken in this fashion approximately every 30 days over the 24-month monitoring period. Additionally, samples coming from the raw manure receiving tank and from the combined imported feedstocks tank were also obtained for two sampling dates at the beginning of the monitoring project to characterize the individual influent streams to the digester.

All samples collected during the 24-month monitoring period were sent for analysis to Certified Environmental Services’ (CES) laboratory in Syracuse, NY, approved by the New York State Department of Health, Environmental Laboratory Approval Program (NYSDOH-ELAP #11246). All samples were analyzed in triplicate for: total solids (TS), total volatile solids (VS), chemical oxygen demand (COD), pH, and total volatile acids as acetic acid (TVFA). In addition, the following nutrients were determined in triplicate: total phosphorus (TP), ortho-phosphorus (OP), total Kjeldahl nitrogen (TKN), ammonia-nitrogen (NH3-N) and potassium (K). CES followed the appropriate testing methods outlined in Table 3 for each parameter measured.

Table 3. Standard analytical methods used by CES laboratory for sample analyses.

Parameter	Standard
Total Solids (TS)	EPA 160.3
Total Volatile Solids (VS)	EPA 160.4
Fixed Solids (FS)	EPA 160.4
Volatile Acid as Acetic Acid (TVFA)	SM18 5560C
Chemical Oxygen Demand (COD)	SM18 5220B
pH	SW846 9045
Total Kjeldahl Nitrogen (TKN)	EPA 351.4
Ammonia-Nitrogen (NH3-N)	SM18 4500F
Organic-Nitrogen (ON)	By subtraction: TKN – NH3-N
Total Phosphorous (TP)	EPA 365.3
Ortho Phosphorous (OP)	EPA 365.3
Total Potassium (K)	EPA SW 846 6010

Methane (CH4), carbon dioxide (CO2), hydrogen sulfide (H2S), and oxygen (O2) concentration in biogas, were measured on-site during monthly visits using a Multitec 540 (Sewerin GmbH, Germany), a portable hand-held gas measuring device equipped with infra-red/electrochemical sensors.

What have we learned?

For the entire monitoring project, an average of 1,891±62 lactating cows per day from Synergy Dairy contributed manure to the digester. The average daily loading rate of the digester was 80,408±19,266 gal, where the average percent of imported waste (mostly food-grade residues) co-digested with manure was 25±6% on a volume-to-volume (v/v) basis. The average reduction of organic matter thru the monitoring project was 42% with respect to the influent, while 75% of the odor-causing volatile fatty acids were reduced. In comparison, a previous monitoring study reported by the authors in five manure-based co-digestion operations showed a reduction in organic matter and volatile acids between 36% and 53% and 85% and 91%, respectively. The average daily digester biogas production for the entire monitoring project was 495±78 ft3 per 1,000 lbs of total influent added to the digester, or 173±34 ft3 per cow contribut ing to the digester. The engine-generator set produced an average of 23±7 MWh of electricity per day, from which the average daily parasitic load of the AD system was 3±1 MWh, accounting for approximately 14% of the electricity generated by the plant. Overall, the average capacity factor and online efficiency of the anaerobic digester system during the entire monitoring project were 0.66±0.22 and 80±23%, respectively. The electrical energy generated translated into an overall thermal conversion efficiency of 42±4%. Also, an additional 13±5% of the total energy in the biogas was recovered by the engine as hot water. Thus, an overall 55% (electrical + thermal) of the total energy contained in the input biogas was recovered by the engine-generator set during the monitoring project.

The majority of the challenges experienced by the Synergy AD system were of mechanical origin, whereas 20% were related to the biological process; only 8% of the downtime was due to scheduled systems maintenance. Some of the problems were related to the extreme cold conditions experienced in the Northeast during the period from December 2013 to February 2014. According to NOAA’s National Climatic Data Center, this period was the 34th coldest for the contiguous 48 states since modern records began in 1895, with an average temperature of 31.3F, 1.0F below the 20th century average (NOAA, 2014).

Future Plans

This manure-based anaerobic digester is the 8th New York State digester we have extensively monitored and reported on. Near-term future planned work includes monitoring a lower cost horizontal plug flow digester on a 2,000-cow farm. This digester uses high density polyethylene (HDPE) material heat welded together as the digester vessel.

Authors

Curt Gooch, Senior Extension Associate, Cornell PRO-DAIRY Program cag26@cornell.edu

Rodrigo Labatut

Additional information

A full report, written for the project sponsor, can be found on the Cornell PRO-DAIRY dairy environmental systems website, https://prodairy.cals.cornell.edu/environmental-systems/.

Acknowledgements

First and foremost, we wish to thank the Synergy Dairy Farm, Synergy Biogas, and CH4 Biogas for their collaborative efforts that made this project possible. We also like to thank the project sponsor, the Wyoming County (New York) Industrial Development Agency.

March 5, 2019July 15, 2020

Making Dairy Manure More Valuable Than Milk

Can Anaerobic Digestion Lead to Additional Revenue Streams On a Dairy Farm?

CowPots are the invention of necessity. Brothers Matt and Ben Freund are second generation dairy farmers in the northwest hills of Connecticut. In dairy farming, the most challenging job is to manage the nutrient stream in an environmentally sound manner. In 1997 the brothers installed a methane digester to heat the manure coming out of a cold barn to be able to separate the liquid year round for field application with a drag line system. This made the farm much more efficient and timely while at the same time reducing soil compaction and improving crop yields. The solids which are composted were first used for bedding the herd and are now used to mold the CowPots, whose value far exceeded bedding value. Farmers and gardeners have always considered cow manure a wholesome organic soil amendment for their crops. The challenge was to find a new and better way to get manure to these soils while maintaining value to consumers.

CowPots are a patented, environmentally friendly product made from the nutrient rich manure and are a vehicle for exporting the farm’s excess nutrients. Through production and sales of CowPots the Freunds have reduced the nutrient load on their farm by approximately 11% and have added a significant 2nd income to the dairy operation.

Examples of CowPots Root Example

Emblems of sound stewardship, CowPots are the ideal product for farmers, growers, gardeners — and for the planet.

What did we do?

The idea for using manure solids to fashion a horticultural pot occurred in the mid 1990’s. The dairy farmer’s wife, Theresa owns a seasonal farm market and garden center adjacent to the dairy farm. Matt noticed that when his wife was tilling the soil each spring, the supposed biodegradable pots were still fully intact.

Confronting stricter regulations on nutrient management through state and federal rules, he needed an alternative to the status quo of storing and spreading manure on their 260+ cow dairy farm. Comparing the fibers found in the peat pots to the fibers of the manure solids, he brought his idea to the kitchen. In Matt’s spare time he began forming, pressing, pasting and molding manure fibers into pots (initially working in the greenhouse and using equipment from his wife’s kitchen and not wanting to get divorced, he moved outside to the farm shop). Nearly a decade was spent experimenting through trial and error.

In the mid 2000’s a production prototype was constructed in one bay of the farm shop where 4” pots were formed and placed by hand onto a drying oven. In 2006, CowPots worked with a local company to shrink wrap stacks of pots and sold them for resale at local garden centers and hardware stores in the tri-state area. That same year Freunds received an SBIR grant to further investigate the horticultural benefits of growing in CowPots. Concurrently, UConn and Cornell University conducted trials in greenhouse settings. In 2009, a standalone manufacturing facility was built and the lineup of sizes offered grew. Today the Freunds manufacture 12 size pots for horticultural uses as well as custom shapes for customers.

What have we learned?

Freunds have learned not all dairy fibers are the same. There are numerous activities on any farm which affect the characteristics of this material. Changes in feed, added minerals, digester upsets,composting temperatures, duration in the in-vessel composer and pasturing the herd have been the most influential on Freund’s farm.

Matt Freund with Product CowPots

Future Plans

The Freunds had many goals one of which was not to have CowPots dictate the management of the dairy. Every bucket of manure fiber needs to be tested before it is used for production of CowPots. The equipment is adjusted in response to any changes.

Another goal was to design a production facility with no waste stream. Dry matter of the fiber is very important to achieve this goal. By having nothing but water vapor and finished product exiting the facility, permitting becomes much less difficult and our footprint becomes much smaller.

The CowPots manufacturing facility is fast approaching their production capacity with shifts that run 24/6. New automation in the packaging system will be installed in the coming months for a total of three robots in the facility. Currently, Freunds are putting together an expansion plan to include an additional production line. They are also working with a company in a similar business to look for synergies. Freunds are investigating other waste streams which could be blended with CowPots products to make the end product even better and at a reduced cost. Recently an engineer came on board to identify production inefficiencies within the manufacturing system to help reduce costs. As the market builds, Freunds will be looking for partners to work with in different areas of the country.

Author

Matt Freund, Owner/Inventor matt@cowpots.com

Additional information

http://cowpots.com/

https://www.youtube.com/user/CowPots

Acknowledgements

Northeast SARE, SBIR, USDA NRCS and Rural Development, CT Dept of Agriculture and CT Dept of Energy and Environmental Protection

March 5, 2019March 6, 2019

Renewable Natural Gas – Biogas Cleaning and Upgrading 101

With depressed electrical prices for produced biogas, many projects are now moving towards business models predicated on production of renewable natural gas (RNG). In order to produce RNG, projects must first clean and upgrade raw biogas to pipeline and/or transportation fuel quality through the use of various engineering approaches. In this presentation, an overview of available and emerging biogas cleaning and upgrading technologies are discussed, highlighting positives, negatives and costs.

Who Should Consider Biogas Cleaning?

The aim of this fact sheet is to provide farmers, third party project developers, regulatory agencies, and other stakeholders with a basic understanding of the chemical composition of renewable natural gas, the most appropriate end use options for dairy digesters, and some of the more common techniques used to clean biogas to RNG quality at dairy digesters.

What did we do?

The authors utilized years of research and industry expertise as well as thorough literature search describe the concept of renewable natural gas and the technologies to clean the biogas. The authors aimed to provide information based on the current literature, but not to favor one technology over another.

What have we learned?

When CHP is the end-use of biogas, the most common biogas purification approach for dairy digesters in the US is to remove water vapor and hydrogen sulfide. Existing projects use a variety of approaches, ranging from biological processes (both post digestion and via oxygen injection into the digester) to physical-chemical absorption processes such as iron type-sponge or activated carbon.

However, if RNG is the end-use a higher degree of purity is required. Often times a dedicated water vapor removal unit and hydrogen sulfide scrubbing unit is still required for removal of the bulk of the hydrogen sulfide mass. Thereafter, water scrubbing or PSA are often used to remove carbon dioxide from biogas, producing an RNG fuel that can be utilized in a variety of different ways. Other technologies exist, however their application on dairy digesters has been rather limited due to concerns related to maturity, cost, and complexity. The best technique is also situation-specific, and therefore, it is critical to understand the mechanics of each purification process, its limitations, and its economics before making a decision.

As electrical rates continue to drop throughout the PNW and US, current and new AD project developers are strongly considering a shift from CHP towards higher value end-uses for biogas, particularly RNG. Interest is increasing due to a growing CNG industry in the US, the decoupling of CNG and diesel prices, and the potential for competitive pricing and high revenues in comparison to fossil-CNG, given existing government incentives. Projects are presently limited and business models must still be proven before wide-scale adoption of biogas upgrading technologies within a dairy digester platform. In addition, concerns historically plaguing CHP projects, related to power purchase agreement pricing, interconnection fees, and scaling are still potentially present within a pipeline fuel model. Nonetheless, the potential exists for a new business model approach to AD projects on US farms.

Future Plans

No future plans.

Authors

Craig Frear, Assistant Professor, Washington State University cfrear@wsu.edu

Nick Kennedy, Associate in Research WSU; Georgine Yorgey, Associate in Research WSU; Dan Evans, President Promus Energy; Jim Jensen, Associate in Research, WSU Energy; Chad Kruger, DIrector WSU CSANR

Additional information

For those seeking additional detail, or information about other technologies, more comprehensive reports and reviews are available (Jensen, 2011; Krich et al., 2005; Ryckebosch et al., 2011). This publication is part of the Anaerobic Digestion Systems Series, which aims to provide information that improves decision-making for anaerobic digestion systems.

Acknowledgements

This research was supported by funding from USDA National Institute of Food and Agriculture, Contract #2012-6800219814; National Resources Conservation Service, Conservation Innovation Grants #69-3A75-10-152; Biomass Research Funds from the WSU Agricultural Research Center; and the Washington State Department of Ecology, Waste 2 Resources Program.