Sustainable Dairy Production Housing / Manure System: Compost Bedded Loose Housing Dairy Barn


What Are Compost Bedded Dairy Barns?

In the U.S., the first compost bedded loose housing (CBP) dairy barns were developed by Virginia dairy producers in the 1980’s to increase cow comfort and longevity.  The key component of a CBP dairy barn is a large, open resting area generally bedded with sawdust or dry, fine wood shavings that is tilled to support aerobic composting. Studies in Minnesota in the early 2000’s built a knowledge base which researchers in Kentucky have utilized during the past 5 years  as the foundation for our research and extension activities on the CBP barns, herds housed within them, and assessing compost fertility. CBP barns fit within goals of sustainable agriculture for dairies with less than 500 lactating cows because of benefits to the cow (space, rest, exercise, and social interaction – Videos 1 & 2), the farmer (low investment, labor-extensive, reduced manure storage costs with composted manure under roof), milk production (milk quality, milk yield), and the environment (reduced ammonia and greenhouse gas emissions, odor and dust emissions, reduced energy consumption, improved manure fertility and flexibility to meet nutrient management plans).  Operator experiences and research results of completed and on-going CBP barn projects are presented. 

What we did

Our first activity was to assess the existing CBP barns in KY to establish the reasons for success. Fifty-five known existing CBP dairy barns in KY were visited from September 2010 to March 2011 to determine the management, barn construction details and management factors that lead to successful operation and herd improvements. Five areas of research were subsequently identified. Critics have expressed concerns about mastitis risks in barns.  Environmental mastitis has been the main concern due to the bacterial load in the CBP barn compost. A study was conducted of mastitis incidence and milk Somatic Cell Count (SCC) of CBP barns relative to “gold standard”, sand bedded free stall barns. Dairymen also wanted to have more certainty of the compost nutrient value for land application. A study was initiated to determine N and P in compost and their release for plant uptake during the first year. For one year, bed data for temperature, moisture, nutrient content by depth, and barn climate were collected to understand the seasonal climatic effects on the compost bed and how quickly these effects are seen. Finally, bed tillage, using cultivators or rototillers, was evaluated for effects on bed performance.

What we learned

Facility design, ventilation, timely addition of fresh, dry bedding, frequent and deep stirring, and avoidance of overcrowding are the keys to a good working CBP barn. Poor management may lead to very undesirable compost bed conditions, dirty cows, elevated SCC, and increased clinical mastitis incidence. Most Kentucky dairy producers listed increased cow comfort and welfare as the main benefit to the CBP barn system, while others cited increased cow cleanliness, low maintenance nature of the system, and the barn’s usefulness for special needs and problem cows. Evaluation of annual bed performance data led to development of new compost bed management strategies. Instead of using the hygiene score for cows or bed temperature, moisture content was viewed as the primary measure since it was a leading indicator of the bed before failure. The time between a good performing bed and a poor performing bed was a matter of days when the moisture content exceeds 60% – wb. The comparison of CBP barns to sand bedded freestall barns validated producers’ observations of comparable SCC and mastitis incidence prevalence in CBP barns. Finally, CBP compost added to soil differs in P dynamics depending on soil test P level. In Low Soil Test P (STP) soils the CBP tended to slowly mineralize, and like inorganic P fertilizers, was subject to adsorption. In High STP soil, P in compost was first adsorbed, but then slowly released with time.

Future plans

  1. Computational Fluid Dynamics (CFD) modeling of the compost bed management and barn design alternatives for demonstration to dairymen for planned and existing facilities.
  2. Effect of Rapid Eye Movement (REM) sleep on cow health, production and comfort.
  3. Mastitis incidence as affected by microbial ecology of the cow udder and compost bedded pack.
  4. Life Cycle Assessment (LCA) and economic analysis of system: milk production, barn, and compost disposal.

Authors

Joseph L Taraba, Extension Professor, Biosystems and Agricultural Engineering, University of Kentucky, Lexington KY – joseph.taraba@uky.edu. 859.218.4353.

Jeffery M Bewley, Associate Extension Professor, Animal Food Sciences, University of Kentucky, Lexington KY

George B Day, Adjunct Instructor, Biosystems and Agricultural Engineering, University of Kentucky, Lexington KY

Mark S Coyne, John H. Heick Professorship, Plant and Soil Sciences; University of Kentucky, Lexington KY

Michael Sama, Assistant Professor, Biosystems and Agricultural Engineering, University of Kentucky, Lexington KY

Randi A Black, PhD Graduate Student , Animal Sciences, University of Tennessee, Knoxville TN

Flavio A Damasceno, Professor (Associate), Departamento de Engenharia, Universidade Federal de Lavras, Lavras, MG – Brasil

Elizabeth A Eckelkamp, Graduate Research Assistant, Animal Food Sciences, University of Kentucky, Lexington KY

Leslie A Hammond, Graduate Research Assistant , Plant and Soil Sciences; University of Kentucky, Lexington KY

John Evans, Graduate Research Assistant, Biosystems and Agricultural Engineering, University of Kentucky, Lexington KY

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.

Wet Scrubbers for Cleaning Air Emissions from Animal Housing Curriculum Materials

Air emissions from animal housing systems are being examined more closely for ways to mitigate potentially harmful gases. Wet scrubbers are one way to remove pollutants from air being exhausted from mechanically ventilated buildings.  The materials on this page were developed to assist educators and professors who include wet scrubbers as a topic in their classrooms or educational programs.

Fact Sheets

Roderick B. Manuzun and Lingying Zhao, The Ohio State University; Allison Jonjak, Nebraska

LPES Curriculum Lessons

Technology Summaries

Figure 1. A prototype wet scrubber developed by the Ohio State University for a deep-pit swine facility. Photo courtesy of Lingying Zhao, Ohio State.

This is from a 2008 conference hosted by Iowa State University

Acknowledgements

These materials were developed by the Air Quality Education in Animal Agriculture (AQEAA) project with with financial support from the National Research Initiative Competitive Grant 2007-55112-17856 from the USDA National Institute of Food and Agriculture.

For questions about the materials on this page contact Dr. Linying Zhao, Ohio State University (zhao.119@osu.edu). For questions about the AQEAA project, contact Dr. Rick Stowell, Unviersity of Nebraska (rstowell2@unl.edu).

If you have presentations, photos, video, publications, or other instructional materials that could be added to the curricula on this page, please contact Dr. Zhao or Jill Heemstra (jheemstra@unl.edu).

Efficacy of Vegetative Environmental Buffers to Mitigate Emissions from Tunnel-Ventilated Poultry Houses

Reprinted, with permission, from the proceedings of: Mitigating Air Emissions From Animal Feeding Operations Conference.

The proceedings, “Mitigating Air Emissions from Animal Feeding Operations”, with expanded versions of these summaries can be purchased through the Midwest Plan Service.

This Technology is Applicable To:

Species: Poultry (Broiler and Turkey)
Use Area: Animal Housing
Technology Category: Environmental Barriers
Air Mitigated Pollutants: Dust, Ammonia, Odor

System Summary

Emissions of dust, gases and odor from poultry facilities pose major challenges for the poultry industry worldwide. Cost-effective technologies to abate emissions from modern tunnel-ventilated poultry houses are limited. In 2002 a three-row planting of trees was installed opposite two, 1.2 meter (4 ft) diameter tunnel fans to evaluate vegetative environmental buffers (VEB) as a means of mitigating emissions from the poultry house. The first row, 9.1 meters (30 ft) from the fans was 4.8 meter (16 ft) high bald cypress, followed by 4.3 meter (14 ft) high Leyland cypress and the outer most row of 2.4 meter (8 ft) high Eastern red cedar. Over the next six years the efficacy of these trees to reduce total dust, ammonia and odor was determined. Measurements were taken at 1.2 meter (4 ft) height on 47 days during peak fan operation with market-age broilers. The relative change in concentration across this 6.7 meter (22 ft) wide vegetative buffer found the VEB significantly reduced total dust, ammonia and odor by 56%, 54% and 26%, respectively. Meteorological conditions and the type of crop next to the VEB appeared to influence the efficacy of vegetation to reduce odor. Dust and ammonia concentration was influenced by these factors to a lesser degree. This suggests the use of trees as vegetative filters may offer a long-term, cost-effective means of partially abating emissions from houses. The local poultry industry trade association for the Delmarva Peninsula has hired a coordinator to implement tree plantings around farms to help abate emissions and to be proactive in addressing increasing neighbor-relations concerns.

Applicability and Mitigating Mechanism

  • Certain plants have the ability to absorb ammonia and capture particulates
  • Vegetation also acts as a sink for chemical constituents of odor
  • A properly designed windbreak aids in dispersion and dilutions of odors as well as reducing wind speed
  • A VEB planting has multiple goals; abate emissions, improve neighbor-relations, and provide shade and shelter of the house

Limitations

  • Growers need technical assistance on the proper design, implementation and care of VEB that is tailored to the unique features of each operation
  • Retrofitting a farm with VEB to capture emissions from all fans is difficult.
  • Species of tree and proper implementation influences time required for VEB to become effective in reducing emissions
  • VEB is a practical and multi-purpose BMP to partially abate emissions.

 

Cost

Average cost for implementing a VEB on an existing broiler farm is ~$5,500. Cost range from $1,500 for a limited one-row planting to provide a visual screen of the farm, and up to $12,000 for multi-row plantings around the outside perimeter of the poultry houses. There is limited information on design and efficacy of VEB plantings between houses. Locally, cost-share programs have provided support to cover most of the costs associated with implementing this program. Plantings to address neighbor-relations have been a driving factor in VEB establishment. An estimated 1/3 of all poultry farms have established VEB on the Delmarva Peninsula. A VEB is also a requirement for a new house loan from one of the major lending institutions.

Authors

George Malone1, Gary VanWicklen1, Stephan Collier1
1University of Delaware
Point of Contact:
George Malone, malone@udel.edu

The information provided here was developed for the conference Mitigating Air Emissions From Animal Feeding Operations Conference held in May 2008. To obtain updates, readers are encouraged to contact the author.

Effectiveness of Litter Treatments for Reduction of Ammonia Volatilization in Broiler Production

Reprinted, with permission, from the proceedings of: Mitigating Air Emissions From Animal Feeding Operations Conference.

The proceedings, “Mitigating Air Emissions from Animal Feeding Operations”, with expanded versions of these summaries can be purchased through the Midwest Plan Service.

This Technology is Applicable To:

Species: Poultry (Broiler)
Use Area: Animal Housing
Technology Category: Chemical Amendment
Air Mitigated Pollutants: Ammonia

System Summary

Recently, poultry producers have come under increased regulatory scrutiny regarding the amount and type of emissions exhausted from poultry housing during the course of normal house ventilation. Ammonia and dust have both been discussed as potential problems with poultry house exhausts. Using a litter treatment will have a direct effect on improving litter management, nutrient enrichment, and reducing ammonia volatilization from poultry house litter. Recent research completed in the Department of Poultry Science at Auburn University has focused on a series of experiments to evaluate six litter treatment strategies in reducing ammonia volatilization during broiler production.

Poultry Litter Treatment (PLTTM), granulated aluminum sulfate (Al-ClearTM) (GA), Poultry GuardTM (PG), and Hydrated Lime (HL), were applied at 24.4, 48.8, or 73.2 kg/100 m2 (50, 100, or 150 lbs/1000ft2); liquid aluminum sulfate (A-7TM) (LA), was applied at 81.4, 162.8, or 227.1 L/100m2 (20, 40, or 60 gals/1000ft2); and concentrated sulfuric acid (98% H2SO4) (SA) was applied at 9.75, 19.50, or 29.26 kg/100m2 (20, 40, or 60 lbs/1000ft2) on new pine sawdust bedding and tested against a non-treated control (CON). With the exception of lime, all agents were designed to reduce litter pH to control ammonia. Results show that increased levels of litter treatments can extend their ammonia control usefulness and most worked well with the exception of lime. In these experiments, ammonia levels were often controlled at the intermediate and highest level of application for 35 to 42 days. If more strict environmental regulations are put into effect regarding ammonia emissions from poultry facilities, litter treatments may become an important technique to allow producers to remain compliant.

Applicability and Mitigating Mechanism

  • Reductions in litter pH will effectively reduce ammonia volatilization
  • Acidifying treatments performed longer at higher levels of application
  • Lime application failed to produce any favorable results
  • Litter treatment usage is an important management tool for suppressing ammonia emissions and contributing to bird health

Limitations

  • Most litter treatments loose their effectiveness within 21 days when applied at low levels, but this can be extended if higher rates of application are employed
  • Acidifying litter treatments can be corrosive to handle
  • Costs of litter treatment are variable and attributed to distribution and marketing logistics

Cost

Delivered cost of a litter treatment is highly dependent upon transportation costs and competitive pricing offered among manufacturers and distributors. Also, costs for transporting, handling, and applying dry versus liquid products should also be considered. Due to the competitive nature of pricing among litter treatment products it is difficult to provide a reasonable and consolidated cost for the treatments tested in these experiments. However, it can be concluded that low levels only provide ammonia control during the brooding period (maybe for 3 weeks); whereas higher application rates will extend the effective period for ammonia control, but the producer must balance the cost of applying a higher level of litter treatment with benefits associated with longer ammonia control.

Authors

J.P. Blake, J.B. Hess, and K.S. Macklin, Department of Poultry Science, Auburn University
Point of Contact:
John P. Blake, blakejp@auburn.edu

The information provided here was developed for the conference Mitigating Air Emissions From Animal Feeding Operations Conference held in May 2008. To obtain updates, readers are encouraged to contact the author.

Odorgon: Overhead Spray System to Neutralize Odors

Reprinted, with permission, from the proceedings of: Mitigating Air Emissions From Animal Feeding Operations Conference.

This Technology is Applicable To:

Species: Poultry, Dairy, Beef, Swine
Use Area: Animal Housing
Technology Category: Chemical Amendment
Air Mitigated Pollutants: Ammonia, Hydrogen Sulfide, Odors

System Summary

Odorgon is a water based formulation that is applied in confined animal feeding operations through a high pressure mist system. Odorgon is sprayed on an automated timer basis from the ceilings through high pressure nylon lines and nozzles to neutralize malodors.

Applicability and Mitigating Mechanism

  • Unique class of cationic surfactants
  • Atomized solution sprayed at 600 psi
  • Buffer resulting in non volatile organic salts
  • Greatly reduces ammonia & hydrogen sulfide
  • Creates better environment for animals to thrive in resulting in lower mortality, less culls and less days to finish.
  • Better conditions for workers/employees
  • Mitigates neighbor/social issues

Limitations

  • Water based, subject to freezing
  • Summer use may be curtailed in

open buildings during windy conditions

Cost

Equipment cost for a 42 by 200 foot finishing building with all components installed is approximately $4900. Annual usage for this facility would average $2100 of Odorgon concentrate or .73 per animal unit but could vary with region/climate. Nursery cost for swine is .19 per animal unit. Odorgon is mixed with water at a rate of 50 parts water to 1 part concentrate resulting in a cost of $1.50 per gallon diluted. Cost also varies based on building dimensions and desired results.

Authors

Steve Opheim, VP Klean Air Inc.
Point of Contact:
Ron Hamilton, rrhamilto@aol.com

The information provided here was developed for the conference Mitigating Air Emissions From Animal Feeding Operations Conference held in May 2008. To obtain updates, readers are encouraged to contact the author.

Atomization Treatment to Improve Air Quality in a Swine Concentrated Animal Feeding Operation (CAFO)

Reprinted, with permission, from the proceedings of: Mitigating Air Emissions From Animal Feeding Operations Conference.

The proceedings, “Mitigating Air Emissions from Animal Feeding Operations”, with expanded versions of these summaries can be purchased through the Midwest Plan Service.

This Technology is Applicable To:

Species: Swine
Use Area: Animal Housing
Technology Category: Other Treatment
Air Mitigated Pollutants: Particulate Matter (PM), Viable Bacteria, Ammonia

System Summary

Juergens Environmental Control Systems are designed to reduce particulate matter (PM), viable bacteria and ammonia and utilizes a high pressure atomization solution. Treatment consists of a formulation comprising proprietary proportions of corn oil, citric acid, ethyl alcohol, eucalyptus, vanilla and water. The formulation was developed to reduce airborne PM and ammonia through short- and long-term mechanisms. The short-term mechanisms include oil encapsulation through electrostatic attraction and coagulation. Long-term reductions occur through the suppression of dust re-suspension. Citric acid is added to neutralize gaseous ammonia. Alcohol helps dry the atomized aerosol and serves as an adjuvant so that formulation components are in complete suspension. Vanilla is added providing a deception for the olfactory senses, and eucalyptus for its respiratory medicinal property. Final formulation is atomized for 5 seconds, six times a day at a pressure of 235 psi (1620 kPa) and a rate of 45 mL/m2. The nozzles are located on the ceiling at 5 or 10 foot centers for complete coverage of the treated area and were designed to produce an aerosol 1-10 ímin diameter under conditions of this formulation and pressure.

Applicability and Mitigating Mechanism

  • Atomization treatment is effective at swine housing systems, such as in finishing, breeding and gestation production systems.
  • The oil is in a water formulation that includes alcohol, citric acid, vanilla and eucalyptus to dry and help mix the atomization solution, neutralize gaseous ammonia, and provide a pleasant odor, respectively.
  • The oil formulation is applied under high pressure, yielding micron-sized charged particles that efficiently remove PM through electrostatic attraction and coagulation.

Limitations

  • Atomization treatment is effective at swine housing systems, such as in finishing, breeding and gestation production systems.
  • The oil is in a water formulation that includes alcohol, citric acid, vanilla and eucalyptus to dry and help mix the atomization solution, neutralize gaseous ammonia, and provide a pleasant odor, respectively.
  • The oil formulation is applied under high pressure, yielding micron-sized charged particles that efficiently remove PM through electrostatic attraction and coagulation.

Cost

Field application of the atomization system and solutions are subject to change. The fixed cost of the system for 1000 – 8000-pig finishing operation averages $1.96 – $7.79 per pig per 3 year term (shipping and installation labor not included). The cost of atomization operating averages $ 0.01 per pig per day over one year. The fixed cost of the system for 500-5000-sow operation averages $9.00 – $16.00 per sow per 3 year term (shipping and installation labor not included). The cost of atomization averages $.01 per sow per day over one year.

Authors

Peter E. Juergens1, Gary L. Rapp11Juergens Environmental Control
Point of Contact:
Gary Rapp, garyrapp@westianet.net

The information provided here was developed for the conference Mitigating Air Emissions From Animal Feeding Operations Conference held in May 2008. To obtain updates, readers are encouraged to contact the author.

Ozone Application for Mitigating Ammonia Emission from Poultry Manure: Field and Laboratory Evaluations

Reprinted, with permission, from the proceedings of: Mitigating Air Emissions From Animal Feeding Operations Conference.

The proceedings, “Mitigating Air Emissions from Animal Feeding Operations”, with expanded versions of these summaries can be purchased through the Midwest Plan Service.

This Technology is Applicable To:

Species: Poultry
Use Area: Animal Housing
Technology Category: Other Treatment
Air Mitigated Pollutants: Ammonia

System Summary

House ozonation is a controversial technique that has been used in the literature for broiler house cleaning and in-house air contaminant control. Field evaluation in this reported study suggests that ozonation cannot effectively remove ammonia from air inside the broiler houses. Moreover, it caused a negative effect on feed conversion in two of the five flocks evaluated and in the average of five flocks. The laboratory study on this technique indicates that zone does not reaction with NH3 in days even at ozone concentration above 1 ppm, which was more than 10 times higher than the health safety limit set by OSHA. The laboratory tests also show significantly higher level of fine/ultra fine particles / aerosols in the ozone treated environment as compared with the environment without ozone treatment. The direct application of ozonation technique for ammonia mitigation in the animal facilities is not recommended.

Applicability and Mitigating Mechanism

  • Ammonia may be oxidized by ozone.
  • The direct application of ozonation technique for ammonia mitigation in the animal facilities is not recommended.

Limitations

  • In-house ozonation at the threshold limits for public health standards is not effective at mitigating ammonia concentration inside the broiler houses
  • Ozone treatment had positive effects on broiler performance in two broiler flocks and adverse impact in two flocks
  • Higher level of fine / ultra fine particles / aerosols was observed in ozone treated environment.

Cost

In-house ozone application caused a negative effect on feed conversion in two of the five flocks evaluated and in the average of five flocks. After 5 flocks the ozonation treatment resulted in an economical loss of $345. Taking in consideration that installation costs are close to $20,000 for two houses, it is very unlikely that the use of ozonation is economically feasible to be used in the poultry industry

Authors

Lingjuan Wang1, Edgar O. Oviedo-Rondon2, John Small2, Qianfeng Li1, Zifei Liu11Department of Biological and Agricultural Engineering, 2 Department of Poultry Science, North Carolina State University
Point of Contact:
Lingjuan Wang, lwang5@ncsu.edu or edgar_oviedo@ncsu.edu

The information provided here was developed for the conference Mitigating Air Emissions From Animal Feeding Operations Conference held in May 2008. To obtain updates, readers are encouraged to contact the author.

Dust and Ammonia Control in Poultry Production Facilities Using an Electrostatic Space Charge System

Reprinted, with permission, from the proceedings of: Mitigating Air Emissions From Animal Feeding Operations Conference.

The proceedings, “Mitigating Air Emissions from Animal Feeding Operations”, with expanded versions of these summaries can be purchased through the Midwest Plan Service.

This Technology is Applicable To:

Species: Poultry
Use Area: Animal Housing
Technology Category: Other Treatment
Air Mitigated Pollutants: Particulate Matter, Ammonia

System Summary

Air quality within poultry production housing has been a major concern for years, particularly with regard to poultry health. The search for strategies to reduce particulate matter and ammonia emissions from animal housing has led to considerable interest in the poultry industry for practical systems to reduce these air emissions. An electrostatic space charge system (ESCS) was designed to reduce aerial dust and ammonia concentrations within a commercial broiler production house. A study was conducted within a commercial broiler house to evaluate the effectiveness of an ESCS for reducing dust and ammonia concentrations over a period of seven flocks. Results of this study indicate the ESCS significantly reduced airborne dust by an average of 43 percent and reduced ammonia by an average of 13 percent. Commercial application of this technology within the production house has the potential to improve in-house air quality and reduce emissions. Electrostatic fields have not been shown to produce adverse health effects in animals or humans. No differences in bird activity were observed in the form of decreased water consumption or increased mortality. No adverse effects of the continuous charge were observed in the form of stray voltage or static discharge at the feeder and water lines.

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Applicability and Mitigating Mechanism

  • An Electrostatic Space Charge System transfers a strong negative charge to airborne dust particles
  • The negatively charged particles precipitate out of the air to grounded surfaces.
  • Nitrogen compounds attached to the dust will also precipitate out of the air.
  • Application of an electrostatic space charge can be effective in reducing poultry house dust and ammonia concentrations in floor-raised meat-bird housing.
  • The system has the potential for use as an emissions control device exterior to animal housing.

 

Limitations

  • The incidences of static discharge to workers were minimal. The intensity of a discharge from direct contact with an ESCS ionizer was similar to touching a spark plug wire on a gasoline engine.

Cost

The cost of materials and installation of the experimental ESCS unit was approximately $4,000. Power consumption of the entire system was less than 100 watts during operation. It is reasonable to assume that a commercially available product would have a reduced capital outlay and quicker return on investment than the experimental prototype used within this study.

Authors

C.W. Ritz1, B.W. Mitchell2, B.D. Fairchild1, M. Czarick1, J.W. Worley11University of Georgia, 2 USDA Agricultural Research Service
Point of Contact:
Casey W. Ritz, critz@uga.edu

The information provided here was developed for the conference Mitigating Air Emissions From Animal Feeding Operations Conference held in May 2008. To obtain updates, readers are encouraged to contact the author.

Effects of Waste Management Techniques to Reduce Dairy Emissions from Freestall Housing

Reprinted, with permission, from the proceedings of: Mitigating Air Emissions From Animal Feeding Operations Conference.

The proceedings, “Mitigating Air Emissions from Animal Feeding Operations”, with expanded versions of these summaries can be purchased through the Midwest Plan Service.

This Technology is Applicable To:

Species: Dairy
Use Area: Animal Housing
Technology Category: Management
Air Mitigated Pollutants: Volatile Organic Compounds, Ethanol & Methanol

System Summary

Recent dairy emission research has identified alcohols (methanol and ethanol) as the major volatile organic compound (VOC) group originating from fresh waste (Shaw et al., 2007; Sun et al., 2008). Effective control of these alcohols from dairies will help the dairy industry meet regulatory standards, satisfy public concerns, and improve local and regional air quality. Enhancing industry typical freestall waste management practices, which currently are predominant practices like flushing and scraping of fresh waste, may provide a large impact on mitigation of oxygenated VOC emissions in a cost effective manner.

Our research has shown that flushing is more effective than scraping in reducing methanol (MeOH) and ethanol (EtOH) emissions from barns. Flushing three times daily versus scraping three times daily yields an emission reduction efficiency of 50% for both MeOH and EtOH. Furthermore, flushing frequency by itself significantly reduces emissions. A comparison of 3 times versus 6 times flushing daily showed decreased emissions by 79% for MeOH and 63% for EtOH.

Applicability and Mitigating Mechanism

  • Oxygenated VOC (e.g., alcohols MeOH and EtOH) are produced by fermenting microbes present in fresh waste
  • Frequent waste removal effectively mitigates MeOH and EtOH emissions from fresh waste
  • VOC alcohols are water-soluble and become effectively trapped in water when flushed
  • Flushing is more effective than scraping, and increasing flushing frequency further decreases VOC emissions

Limitations

  • Scraping methods leave a thin film of manure on concrete ground that continues to produce emissions

Cost

There is no cost associated with increasing the flushing frequency of a liquid manure handling system. Essentially, flushing frequency is increased, while the amount of water per flushing event is decreased. Since the water used to flush barns is recycled water from the lagoons, there is no cost to re-circulate lagoon water through the barn alleys.

Authors

M. Calvo, K. Stackhouse, Y. Zhao, Y. Pan, Ts Armitage, and F. Mitloehner, University of California, Davis
Point of Contact:
Frank Mitloehner, fmmitloehner@ucdavis.edu

The information provided here was developed for the conference Mitigating Air Emissions From Animal Feeding Operations Conference held in May 2008. To obtain updates, readers are encouraged to contact the author.

Dietary manipulations to lower ammonia emission from laying-hen manure

Reprinted, with permission, from the proceedings of: Mitigating Air Emissions From Animal Feeding Operations Conference.

This Technology is Applicable To:

Species: Poultry (Layers)
Use Area: Animal Housing
Technology Category: Ration Manipulation
Air Mitigated Pollutants: Ammonia

System Summary

Dietary manipulation has been shown to lower ammonia emission from laying-hen manure. Dietary amendments include lowering the protein content of the diet, including high-fiber ingredients such as corn distiller’s dried grains with solubles (DDGS), or including EcoCalTM—a proprietary mixture of calcium sulfate and zeolite. Liang et al. (2005) showed that a 1% lower crude protein diet caused a 10% decrease in ammonia emission from laying hens housed in high-rise houses. Roberts et al. (2007) found 40% lower ammonia emission from manure of hens fed 10% DDGS, 38% lower emission when hens were fed 7.3% wheat middlings, and 26% lower emission when hens were fed 4.8% soybean hulls compared to a standard diet. Field research from our group indicates that 3.5% dietary EcoCal lowers ammonia emission by 23%. Research has also evaluated the egg production from hens fed each of the adjusted diets and demonstrated that, when diets are properly formulated, egg production will be similar to that from hens fed a standard control diet.

Applicability and Mitigating Mechanism

  • Ammonia volatilization from laying-hen manure is affected by manure pH, content and chemical form of nitrogen, moisture content, and physical handling of manure
  • Low protein diets lower nitrogen content of the manure
  • High-fiber diets lower manure pH
  • In EcoCal, calcium sulfate lowers manure pH and zeolite binds ammonia, preventing or reducing volatilization

Limitations

  • High-fiber ingredients may not be suitable for nutrient-dense diets
  • Amino acid requirements of hens must be precisely known in order to formulate low-protein diets and maintain egg production
  • EcoCal adds cost to the diet with little nutrient addition
  • Diet cost and ammonia reduction must be evaluated for each individual egg production situation

Cost

The cost of diet modifications must be determined for each individual egg production situation. Feed ingredients are often priced according to private contracts and proximity to the supplier. Feed ingredients can only be added to the diet in exchange for other ingredients (mainly corn and soybean meal), making the evaluation of price amongst ingredients difficult. This exchange of one ingredient for another should be analyzed as the total diet cost of a nutritionally balanced diet, considering all ingredients together. Least-cost diet formulations consider the cost of an ingredient with regards to nutrient content. High-fiber ingredients are typically going to have a relatively low energy content and varying contents of digestible amino acids and minerals, which can be valued in the diet formulation. Low-crude protein diets are formulated by adding crystalline amino acids to the diet, replacing soybean meal and increasing corn. These diets may be cost-effective if the price of amino acids is favorable. EcoCal contributes some calcium to the diet, partially replacing limestone, a relatively inexpensive diet component.

Authors

S.A. Roberts1, H.Xin1, H. Li1, R.T. Burns1, K. Bregendahl1, E.C. Hale III3
1Iowa State University, Ames, Iowa, 2 Rose Acre Farms, Seymore, Indiana
Point of Contact:
hxin@iastate.edu

The information provided here was developed for the conference Mitigating Air Emissions From Animal Feeding Operations Conference held in May 2008. To obtain updates, readers are encouraged to contact the author.