Side-dressing Emerged Corn with Liquid Livestock Manure

The application of livestock manure to farm fields has always been an expense for producers. On-farm research plots were assessed in Ohio following application of  liquid swine and liquid dairy manure using drag hoses to provide side-dress nitrogen to emerged corn. A six-inch diameter drag hose was used to side-dress corn with swine finishing manure at the V3 stage for four crop seasons. The manure was incorporated at a rate of 6,500 gallons per acre to replace purchased commercial side-dress nitrogen. Plot yield results indicated liquid swine manure produced higher yields when compared to 28% urea ammonium nitrate fertilizer when applied at similar nitrogen levels and the cost savings on purchased fertilizer paid for the manure application cost. The use of liquid manure to sidedress corn can provide a new window of time for manure application in Ohio and apply manure when the nutrients could be utilized by a growing crop.


The process of applying liquid swine finishing manure to farm fields represents a significant expense for livestock producers despite the value of the nitrogen, phosphorus and potash contained in the manure. Ohio farmers continue to reduce wheat acreage shifting more of their manure application to the fall application window. The ammonium nitrogen in fall-applied manure is subject to loss before a crop is planted the following season. In the Western Lake Erie Basin of Ohio, an area over three million acres in size, surveys have shown approximate half the livestock manure generated annually is applied in the fall after crops are harvested (Zhang et al., 2015). This allows much of the manure nitrogen to be lost to leaching before the following crop season. Recent research has determined the amount of nitrogen entering Lake Erie influences the toxicity of the hazardous algae blooms.

The ammonium nitrogen in fall applied swine finishing manure can be captured by growing cover crops. A fall cover crop study (Sundermeier, 2010) indicated that an actively growing radish crop reduced soil nitrate nitrogen levels from 21.3 ppm to 6.5 ppm. This prevented the nitrogen from being lost from the field, but only a portion of the organic matter created would mineralize the following crop season to provide nitrogen for a growing crop.

The incorporation of swine finishing manure directly into a growing corn crop with a manure tanker has proven to provide corn yields similar to commercial fertilizer (Arnold et al., 2017). However, Arnold et al. noted soil compaction was a concern with the heavy manure tanker. Using a drag hose to incorporate the manure into emerged corn should overcome the soil compaction concern and allow the corn crop to utilize the available nitrogen in the swine finishing manure. The money saved by not needing to purchase commercial nitrogen to side-dress the corn crop could exceed the cost of the manure application.

What did we do?

This study was designed to determine whether the ammonium nitrogen in liquid swine finishing manure could produce corn yields similar to commercial 28% urea ammonium nitrate (UAN) when the manure was side-dressed on emerged corn using an injection toolbar and soft drag hose (Figure 1).

Figure 1. Side-dressing V2 corn with liquid manure.
Figure 1. Side-dressing V2 corn with liquid manure.

In each of the four years of this complete block design study, started in 2014, manure was incorporated at a rate of 6,500 gallons per acre to provide approximately 210 pounds per acre of nitrogen. The 28% UAN treatment was applied at approximately 70 gallons per acre to provide 210 pounds of nitrogen per acre. All treatments also received 10 gallons of 28 percent UAN as a row starter fertilizer at planting time to provide approximately 30 pounds of nitrogen. The two treatments (manure and commercial fertilizer) were replicated three times each season.

Figure 2. Manure drag hose across V3 corn.
Figure 2. Manure drag hose across V3 corn.

To fit the needs of the commercial manure drag hose operator, each year the corn fields were planted at a 45 degree angle with a 12-row planter using auto-steer. This allowed the commercial manure applicator to stretch the empty manure hose diagonally across the field from one corner to the other at the start of the manure application process (Figure 2).This divided the square field into two triangles and the applicator could apply manure to the entire field without the need of a second tractor to assist in moving the full manure hose. The field had 36 rows (90 feet) of end rows completely around each field allowing the drag hose operator sufficient room to make turns and keep the manure within the boundaries of the field.

The manure came from a 2,450 head swine finishing building with an eight foot deep pit under the animals. This finishing building design is common in Ohio. The manure was pumped through an eight inch diameter hose to the edge of the corn field. A six inch diameter drag hose was pulled across the field during the manure application process.

Figure 3. Drag hose damage caused the corn to lean for about a day.
Figure 3. Drag hose damage caused the corn to lean for about a day.

The corn flattened by the hose typically recovered, i.e. was standing upright, by the following day (Figure 3). The pressure in the hose at the building was more than 200 pounds per square inch. The hose pressure at the toolbar in the field was approximately 30 pounds per square inch. The flow rate was typically between 1,400 and 2,000 gallons per minute depending on the type of pumping equipment used, the diameter of the hoses used, and the distance from the manure storage site to the field during each of the four years.

Manure samples were collected and analyzed during the application process each season. The nitrogen, phosphorus and potassium content of the manure was similar each year so application rates were kept the same each season. The analysis indicated the manure contained 32.1 pounds of available nitrogen, 18.0 pounds of P205 and 24.9 of K20 per 1,000 gallons (Table 1).

Table 1. Average nutrient analysis of swine finishing manure applied.
Nutrient Pounds per 1,000 gallons
 Total Nitrogen 34.3
 Ammonium Nitrogen (NH4) 31.0
 Organic Nitrogen 2.2
 Available Nitrogen 32.1
 Phosphorus (P2O5) 18.0
 Potash (K2O) 24.9

The liquid manure application toolbar had rolling coulter manure application units with a wavy coulter tilling up a strip of soil approximately six inches deep and three inches wide. The manure boot applied manure over the tilled strip and the manure was covered by a pair of notched soil closing wheels. Treatments were approximately 1,200 feet long and 30 feet (12 rows) wide. The auto-steer unit used for planting the crop was transferred from the planting tractor to the 275 horsepower tillage tractor, attached to the toolbar and drag hose, for the manure application. The center unit on the toolbar was removed to prevent tillage and manure application to the center row. This enabled the drag hose to ride higher on the soil surface and lessen the scouring of the field. The manure for the center row was diverted to each side so each side received 150% of the normal manure application rate. 

In each year of the study manure was not applied to three strips, 12 rows wide, in each field. These strips were fertilized with 28% UAN the same day with the same rate of nitrogen contained in the swine finishing manure. These commercial fertilizer strips did, however, have the drag hose pulled across them as the commercial manure applicator applied manure to all other parts of the fields. Commercial 28% UAN was applied to the ends of the corn fields and edges of the corn fields where the swine manure could not be incorporated.

The fields were no-till or minimum-till and the previous crop each year was soybeans. Plant population counts were conducted each year of the study. The predominant soil type in the fields were Blount Silt loam, end moraine 0 to 2 or 2 to 4% slopes

Soil samples of each of the four fields in this study showed P205  and K20 levels to be in the maintenance range. The Mehlich III P205  levels ranged from 59 to 81 ppm and the K20 levels ranged from 149 ppm to 184 ppm (Table 2).

Table 2. Annual soil nutrient test results (Mehlich III).
2014 2015 2016 2017
 pH 6.7 7.0 7.0 6.8
 Organic Matter (%) 2.9 2.5 2.6 2.8
 P2O5 (ppm) 66 76 81 59
 K2O (ppm) 161 149 162 184

At harvest time each year, yields and moisture data were collected using the combine’s monitor. The monitor was calibrated each season before the manure side-dress plots were harvested. All yields were adjusted for moisture. Yield data were analyzed by ANOVA at the 0.10 probability level. 

What we have learned?

Over the four years of this study the incorporated swine finishing manure treatments increased yields when compared to the incorporated 28% UAN treatments by an average of 14.8 bushels per acre (Table 3). This varied from no yield increase the 1st year (2014) to 33 bushel per acre yield increase in 2015, an unusually wet growing season.

Table 3. Corn yield for treatments comparing nitrogen applied as UAN at planting to side-dressed hog manure. Subscript letters a and b indicate yields that year were statistically different using ANOVA at 0.10 probability level.

Yield in Bushels per Acre






4-year ave.

 Incorporated 28 percent UAN






 Incorporated swine manure






 Least Significant Difference (0.10)





 Coefficient of Variability





The normal accumulated precipitation for the growing season (April 1 through September 30) in this area of Ohio is 23.3 inches. The 2015 season was much wetter than normal, and the 2016 season was drier than normal (Table 4).

Table 4. Annual planting dates and normal and observed temperature and precipitation data from April 1 through September 30.
2014 2015 2016 2017
 Corn planting date April 25 May 15 April 20 June 1
 Normal precipitation (inches) 23.3 23.3 23.3 23.3
 Actual precipitation (inches) 21.0 32.6 16.5 23.6
 Historical average temp (°F) 65.7 65.7 65.7 65.7
 Actual average temp (°F) 65.3 66.2 67.2 65.9
 Average high temp (°F) 76.8 77.6 78.8 77.4
 Average low temp (°F) 54.8 55.8 56.7 55.4
 Total growing degree days 2,876 3,006 3,272 2,960

The application of 6,500 gallons per acre of swine finishing manure supplied approximately 210 pounds per acre of side-dress nitrogen for the corn crop while also supplying sufficient phosphorus and potash for the corn crop and the soybean crop the following year without applying excessive phosphorus (Table 5). 

Table 5. Nutrient balance of swine finishing manure side-dress of corn. Nutrient removal rates are from Vitosh et al., 2003 (Tri-State Soil Fertility Guide).
 Crop Nutrient removal in pounds per bushel:

200 bushel per acre corn crop followed by a 60 bushel per acre soybean crop

Available nitrogen (ammonium nitrogen + half the organic nitrogen)
P205 K20 P205 K20 N
 Corn 0.37 0.27 74 48
 Soybeans 0.80 1.40 54 84
 Total nutrients removed 122 138
 Nutrient content of 6,500 gallons of swine finishing manure applied 117 162 210
 Net nutrients -5 +24

In the first year of this study (2014) the field conditions for manure application were less than ideal. The field was wet and the drag hose scoured more than an inch of soil from the field resulting in some of the V1 corn plants being buried and others being pulled out. This reduced the final plant population of the corn rows next to the drag hose by approximately three thousand plants per acre. In each of the following seasons, when V3 plants were side-dressed, the field conditions were firmer and stand loss from the drag hose was not an issue. This stand reduction may have been the reason why 2014 was the only season in which manure did not yield statistically better than the commercial fertilizer.

The hose dragged across emerged plants caused an obvious lean immediately after the application process. By the following day all the plants were upright again. Stand counts indicated approximately 32,000 plants per acre across both treatments in the 2015, 2016, and 2017 seasons.

The 2015 crop season had the largest difference in crop yields between the treatments. Rainfall that season was more than nine inches above normal (Table 4). Most of this extra rainfall fell during the 35 days following the side-dress treatments. We theorize that the lower yields with the UAN treatment was a result of a greater portion of the commercial fertilizer nitrogen being lost to either denitrification or leaching than the manure nitrogen during that time period.

In the 2017 season the corn was originally planted on April 25. Emergence was so poor as to justify replanting, but field conditions were not firm enough to replant until June. The side-dress applications took place two weeks after planting as the corn grew rapidly with the warm temperatures.

The swine finishing manure application rate of 6,500 gallons per acre provided more than an adequate amount of nitrogen for the corn crop while being just short of balancing phosphorus for the two year needs of a corn-soybean rotation. The amount of potash applied with the manure was 24 pounds more than needed for the crop rotation.

The cost of purchasing 28 percent UAN fertilizer to side-dress corn averaged approximately 40 cents per pound during the four years of this study. At an application rate of 210 pounds per acre the commercial fertilizer side-dress cost was $84.00 per acre (210 pounds * $0.40 per pound). The landowner’s custom cost for applying liquid swine finishing manure was $8.00 per 1,000 gallons or $52.00 per acre (6,500 gallons at $8.00 per 1,000 gallons). The cooperating farmers in this study valued his corn at $3.40 and the 14.8 bushel advantage for the manure treated plots were valued at $50.32 per acre. He also did not need to purchase side-dress nitrogen for the acres where manure was applied, and this saved an additional $84.00 per acre.

Future plans

In this study the application of liquid swine finishing manure at side-dress produced higher corn yields, compared to commercial fertilizer, in three of the four study years. Incorporating liquid swine finishing manure as a side-dress nitrogen source to emerged corn can boost yields, reduce nutrient losses, and give livestock producers another window of time to apply manure to farm fields in-season. The money saved on purchasing commercial side-dress nitrogen can pay for the cost of the manure application to an emerged corn crop.

Ohio State University extension now owns three 12-row manure side-dress toolbars which are being loaned to livestock producers and commercial manure applicators for their use to side-dress emerged corn. We discovered that very few commercial manure applicators in Ohio currently have row-ready tractors and only a small percentage of livestock producers have large enough tractors to pull the drag hoses. Grant monies have also been secured to provide tractors to pull the sidedress toolbars.

There is strong interest from commercial manure applicators to apply manure to corn fields. This practice enables them to apply more total gallons of manure in a year. Current indications are that the application of manure to corn fields will continue to expand in the years ahead as commercial applicators gear up for this practice. Every gallon of manure applied to a growing corn crop in early June is one less gallon likely to be applied during the fall application window.


Arnold, G. , Field Specialists, Manure Nutrient Management Application, Ohio State University Extension.
Custer, S., County Extension Educator, Darke County, Ohio State University

Additional information

Arnold, G. J. (2015). Corn yield results from side-dressing with liquid livestock manure. Journal of the NACAA, 8(2). Retrieved from

Sundermeier, A. (2010). Nutrient management with cover crops. Journal of the NACAA, 3(1). Retrieved from

Vitosh, M. L., Johnson, J. W., & Mengel, D. B. (2003). Tri-state Fertilizer Recommendations for Corn, Soybeans, Wheat and Alfalfa. Purdue Extension, Lafayette, IN.

Zhang, W., Wilson, R. S., Burnett, E., Irwin, E. G., & Martin, J. F. (2016). What motivates farmers to apply phosphorus at the “right” time? Survey evidence from the Western Lake Erie Basin. Journal of Great Lakes Research, 42(6), 1343–1356.

Facebook Page: Ohio State University Environmental and Manure Management

Ohio State University Extension Nutrient Stewardship YouTube:



Thanks to Harrod Farms of Rossburg, Ohio for working with Ohio State University Extension on this research project



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. 2019. Title of presentation. Waste to Worth. Minneapolis, MN. April 22-26, 2019. URL of this page. Accessed on: today’s date.

Existing Data on Long Term Manure Storages, Opportunities to Assist Decision Makers

Long-term manure storages on dairy farms are temporary containment structures for byproducts of milk production. Manure, milkhouse wash, bedding, leachate, and runoff are stored until they can be utilized as fertilizer, bedding, irrigation, or energy. The practice of long-term storage creates stakeholders who collect data in their interactions with storages. This presents an opportunity to support data driven  decision making on best use and operation of storages.

What Did We Do?

Prevalent stakeholders who collected data on storages were identified and the information they collected was examined. Data that could assist in depicting storage infrastructure was retained. Data not collected but of value to decision makers was noted. From this a combined data set was proposed that could depict the size, state, and impact of storage infrastructure. The feasibility of such a combined data set and opportunities from it were considered.

What Have We Learned?

General volume, general configuration, and year installed are most often collected by stakeholders while detailed configuration and detailed waste type are rarely collected. Cost is not collected. (Table 1) Stakeholders do not collect data on operations of all sizes. Most data is collected on large and medium operations while data is rarely collected on small operations. Stakeholders use their own definitions and classification structures.

Table 1 Combined data to be collected to assist decision makers
Data Specificity Currently collected by
Location County State, NRCS, CNMP
Lat, Long NONE
Storage Volume Total STATE, NRCS, CNMP
Operational STATE, CNMP
Geometric Dimensions STATE, CNMP
Above/Below Ground STATE, NRCS, CNMP
Year Built Year Built STATE, NRCS, CNMP
Year Inspected STATE, CNMP
Year Recertified STATE, CNMP
Year Upgraded STATE, CNMP
Configuration Liner (Dug,Clay,Plastic,Concrete,Steel) STATE, NRCS, CNMP
Certification(313,PE,ACI318,ACI350) STATE, NRCS, CNMP
Cover(none, rain, gas) STATE, NRCS, CNMP
Waste Volume Produced STATE, CNMP
Type(manure,washwater,leachate,runoff) STATE, CNMP
Manure Type(liquid, stack, pack, liquid sand, liquid recycled) CNMP
Advanced Treatment CNMP
Costs Total NONE
Per Component NONE
Operational NONE
*STATE-State of Michigan

*NRCS-United States Department of Agriculture Natural Resources Conservation Service

Table 2 First level characterization
Total Stored Capacity
Precipitation Stored Capacity
Waste Stored Capacity
Produced Waste Volume
Produced Waste Type
Produced Manure Volume
Produced Manure Type
Liner Type
Cover Type
Certification Type

A first level characterization of storage infrastructure is proposed from Table 1, Table 2. Items in the first level characterization depict the location and condition of the storage infrastructure. Each of these items may be represented over a specific geographic area, such as state, watershed, or county. In a yearly inventory each of these items may be represented over time.  

Table 3 Second level characterization
Length of Storage Estimate
Proximity to Sensitive Area Estimate
Storage Density
Seepage Estimate
Emissions Estimate

Using Table 2 a second level characterization is proposed, Table 3. Items in the second level characterization estimate the capacity and impact of the state’s storage infrastructure. Supplementary information to estimate certain parameters is required.  Each of these items may be represented over time and specific geographic area. Cost to implement and operate storage infrastructure are the third characterization, Table 4. Each of these items may be represented over time and specific geographic area.

Table 4 Cost characterization
Cost Estimate
Implement, Per Volume
Per Configuration
Operate, Per Volume
Per Configuration

Combining and characterizing data from different stakeholders can provide a data-driven representation of storage infrastructure. Condition, capability, and impact of the storage infrastructure can be represented over time and geographic area. Monitoring, evaluating actions, forecasting issues, and targeting priority areas1 is made feasible.  Example opportunities are as follows.

Long-term storage is desirable to enable storage of manure during winter months. Combined data can provide feedback on average days of storage in the state or watershed. The cost to achieve target days of storage may be estimated and the days of storage may be tracked over time as a result of funding efforts.

New York State released $50 million for water quality funding, which assisted in the implementation of new storages. In the implementation of these storages opportunity exits to collect cost data to inform future funding levels, quantify the increase in long-term storage provided as a result of the funding, and forecast when these storages are projected to reach the end of their lifecycle2.   

As interest in cover and flare storages increase to offset livestock emissions combined data sets can assist in evaluating feasibility of such a proposal3 4 5. Potential emissions to be captured and cost to implement can be estimated.  

Obstacles to collecting and combining data are cost, insufficiency, and misuse. As specificity in the data to be collected increases so does the cost to collect, combine, and maintain. Additionally, stakeholders have existing data collection infrastructure that must be modified at cost to allow combination. If the combined data set is not sufficiently populated by stakeholders is will depict an inaccurate representation of storage infrastructure. Finally, the risk of misuse and conflict amongst decision makers is present. Stakeholders may purposely or inadvertently use the inventory to reach erroneous conclusions.  

Future Plans

Obstacles to implementation are not insignificant. Detailed analysis is required to determine the exact data to be collected, definitions to be agreed upon, and extent of coverage such that maximum benefit will be derived for decision makers.

Full benefit of storage data is increased by additional data sets such as state-wide livestock numbers, precipitation and temperature distributions, surface water locations, ground water levels, populations center locations, well locations, shallow bedrock locations, karst locations, complaint locations, and operator violations locations. The feasibility of obtaining these data sets should be determined.

The implementation and use of storages has additional stakeholders outside of those identified here. Additional stakeholders should be identified that can enhance or derive value from a combined data set on long term storages, such as manure applicators, handling and advanced treatment industry, extension services, zoning officials, professional engineers, environmental groups, and contractors.


Corresponding author

Michael Krcmarik, P.E., Area Engineer, United States Department of Agriculture Natural Resources Conservation Service, Flint, Michigan

Other authors

Sue Reamer, Environmental Engineer, United States Department of Agriculture Natural Resources   Conservation Service, East Lansing, Michigan

Additional Information

    1. “Conservation Effects Assessment Project (CEAP).”,
    2. $50 Million in Water Quality Funding Available for NY Livestock Farms.” Manure Manager, 27 Sept. 2017,$50-million-in-water-quality-funding-available-for-ny-livestock-farms-30286.
    3. Wright, Peter, and Curt Gooch. “ASABE Annual International Meeting.” Estimating the Economic Value of the Greenhouse Gas Reductions Associated with Dairy Manure Anaerobic Digestions Systems Located in New York State Treating Dairy Manure, July 16-19 2017.
    4. Wightman, J. L., and P. B. Woodbury. 2016. New York Dairy Manure Management Greenhouse Gas Emissions and Mitigation Costs (1992–2022). J. Environ. Qual. 45:266-275. doi:10.2134/jeq2014.06.0269
    5. Barnes, Greg. “Smithfield Announces Plans to Cover Hog Lagoons, Produce Renewable Energy.” North Carolina Health News, 28 Oct. 2018,
    6. Michigan Agriculture Environmental Assurance Program. MAEAP Guidance Document For Comprehensive Nutrient Management Plans. 2015,

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. 2019. Title of presentation. Waste to Worth. Minneapolis, MN. April 22-26, 2019. URL of this page. Accessed on: today’s date.

Preliminary Study of Sand Settling Lane Designs and Performance

Sand settling lanes are increasing in popularity as a solution for reclaiming sand from the waste stream of dairy facilities.  The purpose of this study was to determine:

    • Whether sand settling systems are functioning properly for Illinois dairy facilities.
    • Whether they meet the criteria in NRCS Conservation Practice Standard (CPS) 632 – Waste Separation Facility.
    • Operation and Maintenance (O&M) criteria needed to make sand settling lane systems function properly for these and future designs.
    • Critical criteria for designing sand settling lanes.

What Did We Do?

Five sites with sand settling lanes of different designs were reviewed in Fall, 2016.  All of the sites were dairy facilities with flush systems to remove manure from confinement buildings.  All of the sites used sand from the same geographical region in Southern Illinois. Each site had a different company delivering the sand, but it appeared that some of these sites received sand from the same source.   

Measurements of the parameters that affect the functionality of the sand settling lane were taken.  One important parameter is the type of flush system used on site. A high velocity flush (HVF) system typically has wave velocity 7.5 feet per second (fps).  A low velocity flush (LVF) system has wave velocity about 3 fps. HVF systems usually have a contact time of less than 1 minute while LVF systems typically have a contact time of 10 minutes or longer.

Basic measurements were made at all five sites:  critical elevations of the confinement building flush alley, transition area (where applicable) and sand settling lane, along with lengths and widths of all of these areas.  At each site, a single flush alley was selected for testing the total flush time and the travel time for the leading wave of flush water, for the flush alley, the transition area, and the sand settling lane.  From these measurements, the velocity, flow rate, total flush volume, and surface roughness coefficient (Manning’s n) were calculated for each flush alley.  We also calculated the particle diameter of sand that would settle and estimated the sand recovery performance of the system.    

Calculating the velocity and flow rate for the sand lane was challenging because of the variability in flow depth.  The amount of sand deposition in the lane affected the flow characteristics (not only flow depth, but also slope and roughness coefficient), and varied depending on the location in the lane.  More sand was deposited at the end of the sand lane than the beginning. In cases where the settling lane had not been scraped prior to the test, it was necessary to estimate an effective slope and flow depth based on the sand deposits.  In future measurements, it will be important to measure the extent of sand deposition and depth.

The table below presents some key factors determined for the five sites studied:








Type of flush system (HVF or LVF)






Flush alley velocity (fps)






Lane velocity  (fps)






Hydraulic retention time in the sand lane (minute)






Manning’s n of sand lane






Producer estimated sand recovery


80% (?)




* Site 3 did not contain the entire flush within the alley, so the flush took a very long time to reach the sand lane.  The system was very new and still being fine-tuned.

** Site 5 performed as a settling basin rather than a sand lane, due to inadequate outlet conditions.

The current NRCS CPS 632 requires that the sand lanes be designed for a flow velocity between 1-2 fps, for adequate sand separation.  None of the sites visited met this criterion in the as-built and operated condition. The Standard also requires a hydraulic retention time between 3-5 minutes, which only one of the sites met.  However, some were removing sand satisfactorily; likely due to the gradation being supplied as bedding.

What Have We Learned?

Although some of the factors measured and studied in this analysis were inconclusive, a number of observations and recommendations can be made.

  1. A sand gradation curve should be a requirement for the design; the flow velocity and hydraulic retention time must be adjusted according to sand size and distribution.  This will also allow the designer to predict the sand recovery amounts and thus properly design the storage space for the reclaimed sand.
  2. Better record keeping of actual sand removal from the sand lane is recommended.  Most of the producers stated that they are reclaiming over 80% of the sand, but the piles on site do not suggest that for some producers.  Keeping records would allow them to determine if their operating procedures need to be adjusted.
  3. Better O&M instructions are needed for sand lane systems.  Every producer stated that they do not have or do not know of any O&M instructions for their system; yet this is critical for this type of system to work effectively.  Instructions would assist the producer with fine tuning the system by providing benchmarks to help determine if the system is working properly. Items in the O&M should be:
    • Design flush information, including total flush volume and flush time.  This could be broken down to where all the producer needs to do is measure the time of either the pump filling the tank and/or of the flush to determine if the system is working properly.
    • Allowable removal of liquid waste from the storage facility that supplies the flush liquid.  Instructions should include the lowest allowable liquid level for the liquid waste storages so that the flush water removed will be clean enough for the job.
    • Regular cleaning of the sand lane: this should occur daily or at a minimum once every two days.   If not, the design should account for the difference in slope and roughness coefficient caused by the accumulation of sand in the sand lane.
  4. If a pipe is used as a channel to move material from the flush alley to the sand lane, the velocity needs to be over 5 fps (preferably closer to 8 fps) so that sand does not settle out in the pipeline.  The problem is that when the velocity is that high in the pipeline, it is difficult for the velocity to be slowed to the required speed for the sand lane (1 -2 fps). A plunge pool, extension of the sand lane or other structure is needed to dissipate the energy of the flush water from the pipe before it enters the sand lane.
  5. A more realistic design Manning’s roughness coefficient (n) needs to be used for the concrete of the sand settling lane.  The designs for these sand lanes all included a Manning’s roughness coefficient of 0.015 to 0.017, but when this coefficient was calculated using the actual data collected on the four sites that were operating as sand lanes, the coefficient was much lower: about 0.012 for all of the sites.  This difference in the coefficient does not seem like much but it is significant. If all the other factors are the same but the roughness coefficient is 0.012 instead of 0.015, the velocity for a typical sand lane would change from 3.2 fps (for n = 0.012) to 2.6 fps (n = 0.015).  This 20% change in velocity makes a significant difference in the appropriate length and slope needed for the sand lane to meet the velocity criterion between 1 and 2 fps and actually settle out enough sand to make the sand lane worthwhile.  Using a larger Manning’s roughness coefficient would allow the designer to make the sand lane shorter and/or steeper, but if the larger coefficient is not realized in the as-built condition, performance will suffer.
  6. The design of the outlet from the sand lane to the receiving storage needs to be sized large enough to pass the expected flow without significantly backing up into the sand lane, unless an analysis is done to account for the backup.  Although the ponded water does allow for more sand deposition, it also significantly changes the hydraulic grade of the sand lane, increasing the hydraulic retention time above the allowable limit in the criteria of CPS 632, and affecting performance.

Future Plans

More extensive research is needed on this subject, to confirm the findings of this case study.  More accurate readings should be conducted at these or other sites with fully functioning sand settling lanes using devices that would be more precise than stopwatch recordings.    


Matt Robert, Agricultural Engineer, USDA-NRCS – Illinois

Ruth Book, State Conservation Engineer, USDA-NRCS – Illinois

Additional Information

“Handling Sand-Laden Manure” by J.P. Harner and J.P. Murphy.  Proceedings of the 5th Western Dairy Management Conference.  Las Vegas, NV. April 4-6, 2001. Pp 47-56.

NRCS National Handbook of Conservation Practices, Conservation Practice Standard– Waste Separation Facility, Code 632.


The authors would like to thank the dairy producers at each of the five Illinois sites for allowing NRCS to study the performance of their sand settling lanes.  


Videos, Slideshows and other media


sand lane
Figure 1. Sand settling lane after a flush, showing accumulated sand.  This picture is taken from the beginning of the sand lane. On each side of the sand lane is a concrete waste storage.  An opening for each concrete waste storage is located at the end of the sand lane. Flush water will enter only one storage since one of the openings is always covered.


Figure 2. Sand Lane and concrete waste storage.  The flush water from the sand lane enters the waste storage.  Additional solids settle out in the storage while liquid is pumped to an earthen storage for land application or reused for flush water.

Check out this link to see three videos of a dairy flush system, with sand settling lane and concrete waste storage.

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. 2019. Title of presentation. Waste to Worth. Minneapolis, MN. April 22-26, 2019. URL of this page. Accessed on: today’s date.

Feasibility of Reducing a Dairy Farm’s Manure Enterprise Costs Using a Wet Gasification Technology

Manure management is a major system on dairy farms, and there is a goal to minimize costs and maximize benefits. Technology that would reduce the mass of the manure to be spread, produce energy and a potential by-product for off-farm sales is needed. Adding wet gasification technology to existing manure systems with the goals of reduced spreading costs and possibly increased by-product sales was evaluated on a central New York farm that was considering expanding.  For expansion to be possible, additional cropland was needed to recycle the additional manure at a further distance from the farmstead. An economic analysis examining the potential impact the wet gasification technology would have on the farm was conducted and results were shared with the dairy producer for use in making informed decisions.

What did we do?

A wet gasification technology that was presented by the manufacturer to be able to extract energy from manure solids (also reducing mass) was evaluated to determine the potential as an improvement to the farm’s existing manure management system. Application of this technology on an example farm was investigated to see what the applications might be on the existing farm (1,500 cows and 1,590 acres) and when expanded to 2,500 cows with 2,990 acres of cropland. Current and projected farm data along with cost and performance data from the manufacturer of the gasification system were used to perform an annual economic cost-benefit analysis as a way to determine the value of the system to the farm’s manure management enterprise.

Figure 1. Example Mass and Energy Flows for a Wet Gasification System

What have we learned?

There are many variables to consider, and the results of the sensitivity analysis show that the variables that influence the outcome of the total annual economic cost-benefit analysis are the ones least under the control of the technology provider or farm (capital cost, lost capital rate, milk production change due to bedding use change, nitrogen value of fertilizer, price of electricity, and value of the ash). Annual spreading costs at the time of analysis ranged from $36/acre for close fields with a low amount of manure spread, to $256/acre for further fields spread at a high amount of manure.

For the case farm analyzed, the system economics would only be favorable if optimistic values were assumed for some of the predictor variables such as high prices for the ash by-product and/or higher prices for the excess energy produced. Raw dairy manure’s moisture content is too high for efficient gasification. Wet gasification is better suited to operations where the raw manure has lower moisture content (due to substantial bedding use) or can be pre-processed to obtain  a very dilute liquid stream (that can be spray irrigated) and a solid product, having 25-30% solids, that could be processed by gasification to produce a salable ash. The values for byproducts, energy and nutrients from manure, need to be large enough to support a manure treatment system. Dairy farms need to consider the impact of a manure treatment technology on the whole farm system.

Prices to obtain a zero economic benefit (net benefits minus costs equal $0) for the expanded 2,500-cow dairy in central NY for each variable alone.
Variable Break-Even Price Comments
Capital costs ($/Unit) $0 Wet Gasification

$0 for SLS

$1,750/kW for steam gen set

Assuming grants are available

Assuming a separator already exists

Steam gen-set is $1,750/kW

Electric Price ($/kWh) $0.156/kWh

5M kWh/yr. produced

Includes $0.03/kWh maintenance cost on engine generators. (This is renewable energy but only ~50% reduction in GHG
Hauling cost ($/load) $2,530/load

159 loads/yr. reduced

8,400 gallons/load (approximately a 420-mile round trip)
Ash Sales ($/ton) $374/ton

898 tons/yr. produced

This price includes the reduced hauling costs as the water separated from the ash can be spray irrigated without hauling.

Future Plans

We continue to evaluate manure treatment systems that have the potential to reduce the mass of the manure to be spread, produce energy, partition the nutrients, reduce greenhouse gas emissions, and a produce a potential by-product for off-farm sales and extending this knowledge to dairy operators.

Corresponding author, title, and affiliation

Peter Wright, Agricultural Engineer, Dept. of Animal Science, Cornell University

Other authors

Curt Gooch, Senior Extension Associate at Cornell University, Dept. of Animal Science, PRO-DAIRY

Additional information

Additional project information can be found on the dairy environmental system webpage:


The farm and the wet gasification technology company provided the needed data to make the economic analysis. Funding for this project was supported by Cornell’s Jumpstart program.

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. 2019. Title of presentation. Waste to Worth. Minneapolis, MN. April 22-26, 2019. URL of this page. Accessed on: today’s date.

Characterization of Nutrients and GHG Emissions from Separated Dairy Manure

This study has the objectives of characterizing dairy manure pre and post solid-liquid separation (SLS), estimating and comparing processing efficiencies between different technologies, and relating emissions to manure characteristics by using modeling tools.

What did we do?

Manure samples from nine dairy farms in southern and eastern Wisconsin were collected every two weeks. All nine farms separated manure into liquid and solid streams and seven farms used anaerobic digesters (ADs) prior to solids separation (Table 1). For all farms, manure was sampled pre-processing (untreated manure) and after any individual processing step in order to isolate the performance of each treatment unit at each farm (Figure 1). All manure samples were analyzed for total solids (TS), volatile solids (VS), total nitrogen (TN), ammonia (NH3), total phosphorus (TP), total potassium (TK) and chemical oxygen demand (COD). Separation efficiency was estimated by solving a system of two equations of separation mass balance (Equations 1 and 2) based on the concentrations of each constituent.



        • X (kg) is the constituent under evaluation (e.g. TS, NH3, etc.)
        • [  ] indicates percent concentration in the solid (solid, out), liquid (liquid, out) fractions after separation, and total before separation (total, in)
        • Manure (kg) is the manure mass in the solid (solid, out), liquid (liquid, out) fractions after separation, and total before separation (total, in)

What have we learned?

Both screw press and centrifuge technologies achieve higher separation efficiencies for TS and VS than for TN, NH3, TP, and TK, meaning that more TS and VS stay with the solids fraction. Moreover, NH3 stays almost entirely in the liquid fraction. Results indicate that centrifugation might achieve higher TP separation efficiencies than screw pressing. Greenhouse gas (GHG) emissions, were affected by the management practices used to handle the liquid and solid fractions. Methane emissions from liquid storage are reduced as a percentage of the VS stays with the solids fraction. However, nitrous oxide emissions from the separated solids might increase if separated solids are stored and not quickly land applied or transported outside of the farm for posterior use.     

Future Plans

Analysis for anaerobic digestion efficiency and pathogen inactivation will be incorporated in this study to conduct a complete assessment of manure characteristics after AD and SLS and their impact on different environmental indicators.


Table 1.  Summary of each farm’s manure management process.
Farm ID





Mixed plug flow

Screw press

Dairy manure




Dairy manure

3 Complete Mix

Screw press with blower

Dairy manure


Mixed plug flow

Screw press

Dairy manure


Mixed plug flow

Screw press

Paunch manure, food waste


Mixed plug flow

Screw press

Dairy manure


Mixed plug flow

Screw press

Dairy manure


Complete Mix


Dairy manure, ethanol byproduct, FOG




Dairy manure

AD: anaerobic digestion, SLS: solid-liquid separation, ABRU: aerobic bedding recovery unit , FOG: fat, oil, and grease


Scheme of the manure processing technologies and sampling locations.
Figure 1. Scheme of the manure processing technologies and sampling locations.


Aguirre-Villegas Horacio Andres. Assistant Scientist. Department of Biological Systems Engineering, University of Wisconsin-Madison.

Sharara Mahmoud. Assistant Professor. Department of Biological and Agricultural Engineering. NC State University

Larson Rebecca. Associate Professor. Department of Biological Systems Engineering, University of Wisconsin-Madison

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. 2019. Title of presentation. Waste to Worth. Minneapolis, MN. April 22-26, 2019. URL of this page. Accessed on: today’s date.

Aeration for Elimination of Manure Odor and Manure Runoff: What One Professional Engineer Has Learned in the Past 12 Years

Aerobic treatment has potential to be more practical for any size operation, reduce odors, reduce risk of runoff by facilitating application to growing crops, and reduce energy use when distributing manure nutrients.

Farm-based aeration, created through an upward/outward surface flow, was first introduced in the 1970’s and brought partial success.  With significant performance issues, challenges with struvite within manure recycling pipes/pumps, and the growing trend to store manure within pits under barns, further research with manure aeration was largely abandoned.  Very little research has been done on aerobic treatment within manure storage systems since traditional aeration using air blowers has been considered too expensive. Previous research sought to mimic traditional domestic wastewater treatment systems which also purposely perform denitrification.  Not always a goal for farm operations in years past, retaining Nitrogen within wastes used as fertilizer is now usually a goal.  Thus, past aerobic treatment systems were not designed to fully benefit today’s modern farms.

In 2006, hog producers were introduced to an updated version of equipment providing Widespreading Induced Surface Exchange (WISE) aeration, specifically for reducing hog manure odor while irrigating lagoon effluent.  The results became a “wonder” for the site’s CAFO permit engineer. Documentation showed that significant aeration was occurring at a rate much higher than could occur with the energy input used by traditional bubble blowers.  This indicated that aeration of manure ponds and lagoons may not be too expensive after all.  More questions led to a USDA NRCS-supported study, which revealed much more information and brought out more questions. The final report of that study is available at, along with other information on the technologies described.

 The NRCS-funded study revealed the basis for previous performance failures, while it also showed the basis for getting positive aeration performance at liquid manure storage sites:  Ultimately, this information showed that large reductions of manure odor can be obtained while offering a new paradigm for eliminating most potential manure runoff through WISE aeration as the first step.

The paradigm change summary:

  1. Aeration provides aerobic bacteria based manure decomposition while in storage.
  2. Aerobic bacteria produce only carbon dioxide, which is considered carbon neutral when converting manure’s nutrients to fertilizer, reduced greenhouse gas (Aerobic gives off no other greenhouse gasses such as methane or oxides, and few odors)
  3. “No odor” allows direct distribution of decomposed manure nutrients onto crops during growing season. (Distribution is done during growing season, using automated irrigation equipment).
  4. Low-cost automated manure distribution reduces farm operation costs, but also allows the nutrients to be distributed to equal acres during a wider application time frame (not limited to when crop land is barren in spring or before fall freezeup.)
  5. A wider application time frame allows multiple applications at smaller doses onto growing crops. Depending on nutrient application goals and equipment, irrigation rates can be as little as 1/8th inch of water, multiple times through the year, instead of one large dose.
  6. Irrigation equipment is likely not operating when potential runoff conditions are pending, especially when the entire spring/summer/fall periods are available for distribution.
  7. When nutrients are applied onto growing crops at low dosage rates during periods when irrigation is desired, very little potential for runoff is present. Only a small portion of 1/8” of water onto a crop canopy rarely reaches the ground. The nutrient rich water quickly binds with the dry surface soil when it does get past the crop canopy during summer application.
  8. Current manure distribution distribution requires that most farmers fight to get raw manure distributed onto cropland before spring planting (which is often a wet time of year), OR after crops are harvested and bales removed. Although farmers and regulators wish that all manure handling is performed before freezeup, it is not the case: It happens more than anyone admits.  Manure application to frozen ground is an understated and unquantified manure runoff cause.  Such runoff can be eliminated by the new paradigm of application onto growing crops.

Further, the “side use” of treated effluent has significant benefit compared to raw manure.  Aerobic Bacteria-Laden Effluent (ABLE water) is extremely proficient in its use within flume systems and for automatic flushing of alleys. The aerobic bacteria within the treated water is “hungry” to go to work, to pick up fresh food as it passes over the floor/alley, on its way back to the storage pond.

The layman’s explanation is similar to urban water delivery pipes and wastewater pipes buried within city streets:

  1. Historically, dairy operators quickly learned that fresh well water will create a “slime” on surfaces, causing extremely slippery floors and alleys which injure cows. To eliminate much of the slipperiness, they stopped using fresh water and instead used raw manure from the pond.  In many cases, they would add water to the pond, when manure got too thick and again caused slippery areas.
  2. Unseen by most people are the 2 pipe systems under streets carrying our water and sewer. Factually, one pipe has slime, and the other pipe is amazingly clean: While acknowledging the newspaper notices that fire hydrants are going to be “flushed” several times/year, most don’t realize the purpose for doing so is to flush the slime from our drinking water pipes! The slime is not toxic to humans due to chlorination, but its buildup reduces pipe capacity, and its color is unpleasant to see in drinking water.  In the case of unaerated fresh water used at farms, it tends to grow the slime that dairymen simply can’t afford on their alleys/floors.
  3. Meanwhile, most people won’t look into a sewer manhole to note how “clean as a dinner plate” it looks! Sewerage pipes are designed for high capacity peak flow but normally runn at very low levels. This allows tremendous aeration activity within the system as water tumbles at manholes and as flows change direction.  Thus, the aeration, food, and bacteria within properly operating sewer systems have very little odor, with the bacteria laden effluent continuously cleaning the sewer pipe. Sewer Pipes indeed look “brand new” even after operating for decades!   Those who effectively aerate their manure pond water so they have high aerobic populations within the effluent, and use that effluent for flushing alleys and flumes are quite happy with the resultant cleaning of the alleys, floors, and flumes.

Lastly, ABLE water likely has traits of “compost tea”:  Compost Tea is made by steeping in water, a quantity of completed compost, rich with soluble nutrients, bacteria, fungi, protozoa, nematodes and microarthropods.  After removing the steeped compost solids, the remaining effluent is rich with those items recognized by many as necessary for building the soil and most effective for plant growth.   The tea is to be used quite soon after it is created, but aeration can lengthen the storage period.  Within aerobically treated manure ponds, because aeration is being performed continuously, compost tea-like benefits are anticipated to be included to crops having the WISE treated effluent application.

What did we do?

A basic hypothesis for WISE technology was developed in 2014 to explain why aeration levels are significantly higher compared to bubble blower technology.  This hypothesis explains how/why results are being obtained and allows purposeful thought on how to maximize performance.

Meanwhile, engineering solutions were developed for the two main issues of equipment available at the time: 1) Previous equipment was heavy and required boom trucks/cranes to install/remove it for servicing (250 to 900 lb.), and 2) The propeller orientation/shape would inherently draw in stringy material that wraps on the propeller shaft, which then requires removal (see problem 1).  New equipment was designed that weighs less than 120 lb. and is easily installed by hand (Figure 1).

Figure 1. One of two WISE technology models, this for open ponds (44” wide). The other model fits through a doorway to be installed in the manure storage pits of deep-pit hog barns.
Figure 1. One of two WISE technology models, this for open ponds (44” wide). The other model fits through a doorway to be installed in the manure storage pits of deep-pit hog barns.

What have we learned?

After years of testing the new design, the equipment proved to be able to operate without inviting stringy material to wrap on the propeller and to be easy to handle by hand.  The design was declared an engineering success and marketing began.

In addition, nitrogen retention rates for aerobic manure treatment are much higher than published, most likely due to the traditional domestic wastewater treatment process assumptions of the 1970’s and the use of partial aeration, due to high costs of bubble blowers, instead of continuous aeration used within WISE aeration activity.

Prior to the 2018 North American Manure Expo, data was collected at 3 different farms in the Brooking SD area, each farm having a different brand/style of providing aeration. Due to the uncontrolled variables, results varied within each farm and also varied from the other farms.  Although no clear specific results were determined, one specific trend was that installing equipment at a higher operational rate (1 device/50 animal units) than the study used (1 device/70animal units), offered higher nitrogen retention than can be expected from the NRCS funded study, which is higher than currently published aeration rates.   This leads me to believe that there may be some misunderstood biological process for retaining nitrogen within aerobically treated effluent using WISE aeration.  It appears there are some things unequivocally misunderstood about aerobic manure treatment and the nutrients retained, most likely also associated with the items commonly identified/targeted with Compost Tea discussions.   The potential for changing the current manure handling paradigm to one where odor is not an issue, and application of manure nutrients onto growing crops which might also reduce manure runoff   warrants further study.

The presentation will also touch on some basic misunderstandings about ammonia/ammonium, provide “do’s” and “don’ts” of installations and/or studies, and identify additional subjects for study.

What are the next steps?

  • Associated technology is being developed to perform foliar application. If farmers can’t handle manure differently, why would they do additional work, just to distribute it the same way they do now?  The presentation will include basic information for a Self-Propelled Extremely Wide Portable Linear Irrigator (SPEWPLI).  This equipment is projected to be able to irrigate/fertigate a full 160-acre field in 5 passes, and then be quickly moved to the next field.  It is anticipated that manure pumpers would use existing equipment to deliver liquid manure to fields and use the SPEWPLI equipment as an alternative to conventional drag-hose injection.  Foliar feeding has proven beneficial, applying nutrients directly onto growing crops (in canopy) when they best increase yields. By changing the distribution window to summertime, farmers don’t need to apply only in spring or in fall, or leave fields un-planted so manure can be applied in the summer.

While most farmers will not spend money to buy technology which only rids manure of odor while they continue to handle it as they have in the past, since there is very little economic return for only controlling odor, there are other aspects of WISE aeration technology to provide economic return, which then provides odor relief as a “free” benefit.

  • More information is needed on the benefits of distributing manure nutrients directly to growing crops and on the economics of low-cost, automated systems.
  • More information is needed in maximizing aeration for the energy used by way of this technology.
  • More information is needed in how nitrogen can possibly be tied up and reserved by the other bacteria, fungi, protozoa, nematodes and microarthropods within compost tea-like effluent.

A listing of such subject study items, likely to be doctorate dissertation level projects, will be included in the presentation.

Because our brand resolves issues that other equipment has, we will make it available for academic study at field sites and for others to use for additional research in the use of WISE aeration technology.


John Ries, PE, Pond Lift, Elk Point, SD,

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. 2019. Title of presentation. Waste to Worth. Minneapolis, MN. April 22-26, 2019. URL of this page. Accessed on: today’s date.

Evaluation of current products for use in deep pit swine manure storage structures for mitigation of odors and reduction of NH3, H2S, and VOC emissions from stored swine manure

The main purpose of this research project is an evaluation of the current products available in the open marketplace for using in deep pit swine manure structure as to their effectiveness in mitigation of odors and reduction of hydrogen sulfide (H2S), ammonia (NH3), 11 odorous volatile organic compounds (VOCs) and greenhouse gas (CO2, methane and nitrous oxide) emissions from stored swine manure. At the end of each trial, hydrogen sulfide and ammonia concentrations are measured during and immediately after the manure agitation process to simulate pump-out conditions. In addition, pit manure additives are tested for their impact on manure properties including solids content and microbial community.

What Did We Do?

Figure 1. Reactor simulates swine manure storage with controlled air flow rates.

We are using 15 reactors simulating swine manure storage (Figure 1) filled with fresh swine manure (outsourced from 3 different farms) to test simultaneously four manure additive products using manufacturer recommended dose for each product. Each product is tested in 3 identical dosages and storage conditions. The testing period starts on Day 0 (application of product following the recommended dosage by manufacturer) with weekly additions of manure from the same type of farm. The headspace ventilation of manure storage is identical and controlled to match pit manure storage conditions. Gas and odor samples from manure headspace are collected weekly. Hydrogen sulfide and ammonia concentrations are measured in real time with portable meters (both are calibrated with high precision standard gases). Headspace samples for greenhouse gases are collected with a syringe and vials, and analyzed with a gas chromatograph calibrated for CO2, methane and nitrous oxide. Volatile organic compounds are collected with solid-phase microextraction probes and analyzed with a gas chromatography-mass spectrometry (Atmospheric Environment 150 (2017) 313-321). Odor samples are collected in 10 L Tedlar bags and analyzed using the olfactometer with triangular forced-choice method (Chemosphere, 221 (2019) 787-783). To agitate the manure for pump-out simulation, top and bottom ‘Manure Sampling Ports’ (Figure 1) are connected to a liquid pump and cycling for 5 min. Manure samples are collected at the start and end of the trial and are analyzed for nitrogen content and bacterial populations.

The effectiveness of the product efficacy to mitigate emissions is estimated by comparing gas and odor emissions from the treated and untreated manure (control). The mixed linear model is used to analyze the data for statistical significance.

What we have learned?

Figure 2. Hydrogen sulfide and ammonia concentration increased greatly during agitation process conducted at the end of trial to simulate manure pump-out conditions and assess the instantaneous release of gases. The shade area is the initial 5 minutes of continuous manure agitation.

U.S. pork industry will have science-based, objectively tested information on odor and gas mitigation products. The industry does not need to waste precious resources on products with unproven or questionable performance record. This work addresses the question of odor emissions holistically by focusing on what changes that are occurring over time in the odor/odorants being emitted and how does the tested additive alter manure properties including the microbial community. Additionally, we tested the hydrogen sulfide and ammonia emissions during the agitation process simulating pump-out conditions. For both gases, the emissions increased significantly as shown in Figure 2. The Midwest is an ideal location for swine production facilities as the large expanse of crop production requires large fertilizer inputs, which allows manure to be valued as a fertilizer and recycled and used to support crop production.

Future Plans

We develop and test sustainable technologies for mitigation of odor and gaseous emissions from livestock operations. This involves lab-, pilot-, and farm-scale testing. We are pursuing advanced oxidation (UV light, ozone, plant-based peroxidase) and biochar-based technologies.


Baitong Chen, M.S. student, Iowa State University

Jacek A. Koziel*, Prof., Iowa State University (

Daniel S. Andersen, Assoc. Prof., Iowa State University

David B. Parker, Ph.D., P.E., USDA-ARS-Bushland

Additional Information

  • Heber et al., Laboratory Testing of Commercial Manure Additives for Swine Odor Control. 2001.
  • Lemay, S., Stinson, R., Chenard, L., and Barber, M. Comparative Effectiveness of Five Manure Pit Additives. Prairie Swine Centre and the University of Saskatchewan.
  • 2017 update – Air Quality Laboratory & Olfactometry Laboratory Equipment – Koziel’s Lab. doi: 10.13140/RG.2.2.29681.99688.
  • Maurer, D., J.A. Koziel. 2019. On-farm pilot-scale testing of black ultraviolet light and photocatalytic coating for mitigation of odor, odorous VOCs, and greenhouse gases. Chemosphere, 221, 778-784; doi: 10.1016/j.chemosphere.2019.01.086.
  • Maurer, D.L, A. Bragdon, B. Short, H.K. Ahn, J.A. Koziel. 2018. Improving environmental odor measurements: comparison of lab-based standard method and portable odour measurement technology. Archives of Environmental Protection, 44(2), 100-107.  doi: 10.24425/119699.
  • Maurer, D., J.A. Koziel, K. Bruning, D.B. Parker. 2017. Farm-scale testing of soybean peroxidase and calcium peroxide for surficial swine manure treatment and mitigation of odorous VOCs, ammonia, hydrogen sulfide emissions. Atmospheric Environment, 166, 467-478. doi: 10.​1016/​j.​atmosenv.​2017.​07.​048.
  • Maurer, D., J.A. Koziel, J.D. Harmon, S.J. Hoff, A.M. Rieck-Hinz, D.S Andersen. 2016. Summary of performance data for technologies to control gaseous, odor, and particulate emissions from livestock operations: Air Management Practices Assessment Tool (AMPAT). Data in Brief, 7, 1413-1429. doi: 10.1016/j.dib.2016.03.070.


We are thankful to (1) National Pork Board and Indiana Pork for funding this project (NBP-17-158), (2) cooperating farms for donating swine manure and (3) manufacturers for providing products for testing. We are also thankful to coworkers in Dr. Koziel’s Olfactometry Laboratory and Air Quality Laboratory, especially Dr. Chumki Banik, Hantian Ma, Zhanibek Meiirkhanuly, Lizbeth Plaza-Torres, Jisoo Wi, Myeongseong Lee, Lance Bormann, and Prof. Andrzej Bialowiec.


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. 2019. Title of presentation. Waste to Worth. Minneapolis, MN. April 22-26, 2019. URL of this page. Accessed on: today’s date.