Comp Lessons Learned

TOPICS >> COMPOSTING >> LESSONS LEARNED

Subjects in "Lessons Learned":

Composting
Biology
Methods
Management
Site Consideration
Environmental
Marketing

COMPOSTING

Belt and Ventilation System: Kreher's Poultry Farms
Poultry waste drying and composting demonstration; Integrating the manure collection and handling system (belts with ventilation) with the manure treatment system (composting) optimized the total farming operation. The belt and ventilation system between layer cages allowed more birds per building, better ventilation, drying of the manure for ease of handling and preparation for a compost operation without the addition of amendment.

Biodrying vs Composting: Watershed Agricultural Council, Inc.
Demonstrations of fixed film anaerobic digester; Integrating the manure collection and handling system (belts with ventilation) with the manure treatment system (composting) optimized the total farming operation. The belt and ventilation system between layer cages allowed more birds per building, better ventilation, drying of the manure for ease of handling and preparation for a compost operation without the addition of amendment.

Compost Drying: AA Dairy; Composting marketing has been increasingly successful. This has occurred over time with repeat customers, word of mouth advertising and the use of a website. Prices vary depending on size of the purchase. All the manure solids can be sold.

Drying Compost: Kreher's Poultry Farms
Poultry waste drying and composting demonstration; Composting continues at lower moisture conditions than previously recommended. Mixed compost that has been composting continues to biologically degrade below moisture levels (40%) that are recommended to start composting. Drying below 20% moisture does control additional composting to a low rate.

Marketing Needs: F.A.R.M.E. Institute, Inc.
Anaerobic digester demonstration with biogas fueled micro-turbines; Solid sales marketing needs to be done to sell manure solids. The digested separated solids are homogeneous, dark in color, and have good tilt. They should be preferred over other forms of organic soil amendment. However, without a marketing effort it cannot be assumed that they can be sold at any price. Transportation costs make the market area relatively near to the farm.

Organic Status: Kreher's Poultry Farms
Poultry waste drying and composting demonstration; Value added by certification of organic status, pathogen reduction, and processing (pelletizer) helps make the manure management profitable. Documenting the pathogen reduction during composting, certifying and marketing the dried manure as organic and processing and blending the pelletized manure helped meet their customers’ needs and enabled them to charge a higher price for their product.

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BIOLOGY (recipe)

Amendment: Earthworks
Demonstration of composting service serving multiple farms; Amendment (waxed cardboard not cleanly available) addition is problematic. Compost amendment (and bedding for the cows, which is used to increase the C: N ratio as well) is almost always the lowest price material. This means quality control of it is poor and if a higher use becomes available it is then marketed to that use and becomes unavailable for compost amendment (or bedding).

Pathogens: Cornell Waste Management Institute
Evaluation and optimization of composting systems; Pathogen control varies from site to site. This is probably due to recontamination of the compost. Storage and handling methods vary from site to site

Watershed Agricultural Council, Inc.
Demonstrations of biodrying; Tests involving Ascris worms successfully showed that the biodrying method killed pathogens aver a four-day period even with out mixing. The Ascris eggs were placed in a number of locations in an actively composting pile. After removal at four days the eggs were no longer viable. Control Ascris eggs were still viable. The Ascris eggs are often used to simulate the survival of Cryptosporisium oocycts.

Weather: Watershed Agricultural Council, Inc.
Demonstrations of biodrying; During cold weather negative aeration, sucking air from the top of the pile down into the air channels and up to the fan does work. As the warm saturated air moves out of the piles into the air channels it cools and moisture drops out in the channels. A drainage system with an air lock was designed into the system. However the air passageways had a negative slope at the upper end before they turned vertically up to the fans. This area became blocked plugging the passageway and shutting off the air supply.

Weather: Watershed Agricultural Council, Inc.
Demonstrations of biodrying; Cold weather positive pressure aeration can cause moisture buildup in the top of the piles. As air is pushed into the composting piles the heat from composting allows the dry air to pick up moisture as it move upward. When the now saturated warm air reaches a point close to the surface of the pile, the air is cooled by the cold ambient temperatures and moisture is released. When this occurs inside the pile the moisture builds up in the top layer. While the bottom dries out the moisture in the top keeps the average moisture content in the pile at an elevated level.

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METHODS, OPERATION

Belt and Ventilation System: Kreher's Poultry Farms
Poultry waste drying and composting demonstration; Integrating the manure collection and handling system (belts with ventilation) with the manure treatment system (composting) optimized the total farming operation. The belt and ventilation system between layer cages allowed more birds per building, better ventilation, drying of the manure for ease of handling and preparation for a compost operation without the addition of amendment.

Biodrying vs. Composting: Watershed Agricultural Council, Inc.
Demonstrations of fixed film anaerobic digester; Direct composting with an abundant amendment and a good market may be more profitable than biodrying. If compost can be sold for $10 a cubic yard, and amendment can be obtained cheaply it may make more economic sense to just make good compost and sell it directly instead of using recycled compost as an amendment that minimizes the amount of compost to be sold.

Compost Pile Height: Watershed Agricultural Council, Inc.
Demonstrations of biodrying; Manure/amendment piles higher than 4 ft have poor air porosity if the amendment has little structure. The amendment used in the biodrying project was chopped hay, old silage and/or composted manure. None of these materials has aggregates that would give the pile porosity at moisture contents above 60%. As the piles composted with forced air and without turning they settled so even as they dried they did not achieve porosity sufficient for the fans to move air through.

Computerized Control: Watershed Agricultural Council, Inc.
Demonstrations of biodrying; The computerized control system that monitored the variable speed fans and the temperature of the piles did a good job of both controlling the operation and recording the data. Thermocouples in the piles were used with a logic system that could be adjusted for different operating conditions were used successfully.

Drying: Watershed Agricultural Council, Inc.
Demonstrations of biodrying; The energy from composting and the fans were sufficient to evaporate moisture to reduce 65% moisture content manure/amendment mix to 50% partially composted material with 14 days of controlled aeration and one week of fan drying.

Drying Compost: Kreher's Poultry Farms
Poultry waste drying and composting demonstration; Composting continues at lower moisture conditions than previously recommended. Mixed compost that has been composting continues to biologically degrade below moisture levels (40%) that are recommended to start composting. Drying below 20% moisture does control additional composting to a low rate.

Fans: Watershed Agricultural Council, Inc.
Demonstrations of biodrying; The fans did not deliver the air pressure they were rated at. The required air movement through the composting piles was not met. Manometer measurements verified that the fans rated at 7 inches of water pressure would only produce a maximum of four inches at the fan outlet.

Manure Spreader: Watershed Agricultural Council, Inc.
Demonstrations of biodrying; Having a Vee manure spreader to mix the amendment with the manure and then unload sidewise into the biodrying shed is a feasible way to create uniform piles. A backboard was needed to prevent the manure from shooting all the way through the shed.

Fans: Watershed Agricultural Council, Inc.
Demonstrations of biodrying; The fans did not deliver the air pressure they were rated at. The required air movement through the composting piles was not met. Manometer measurements verified that the fans rated at 7 inches of water pressure would only produce a maximum of four inches at the fan outlet.

Pad Types: Cornell Waste Management Institute
Evaluation and optimization of composting systems; Earthen pads tend to have more mineral matter in the compost than compost made on concrete pads.

Spontaneous Combustion: Kreher's Poultry Farms
Poultry waste drying and composting demonstration; Spontaneous combustion is a possibility for material stored in massive piles at moisture conditions above 25% and lower than 40%. Between these moisture levels stored material needs to be piled at low enough heights so the heat from biological reactions can not cause a runaway chemical reaction and combustions.

Turning Methods: Cornell Waste Management Institute
Evaluation and optimization of composting systems; Mixing by front end loader or with a turner both can achieve mature compost. Depending on the final use either system can be used.

Weather: Watershed Agricultural Council, Inc.
Demonstrations of biodrying; Cold weather positive pressure aeration can cause moisture buildup in the top of the piles. As air is pushed into the composting piles the heat from composting allows the dry air to pick up moisture as it move upward. When the now saturated warm air reaches a point close to the surface of the pile, the air is cooled by the cold ambient temperatures and moisture is released. When this occurs inside the pile the moisture builds up in the top layer. While the bottom dries out the moisture in the top keeps the average moisture content in the pile at an elevated level.

Weather: Watershed Agricultural Council, Inc.
Demonstrations of biodrying; During cold weather negative aeration, sucking air from the top of the pile down into the air channels and up to the fan does work. As the warm saturated air moves out of the piles into the air channels it cools and moisture drops out in the channels. A drainage system with an air lock was designed into the system. However the air passageways had a negative slope at the upper end before they turned vertically up to the fans. This area became blocked plugging the passageway and shutting off the air supply.

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MANAGEMENT OF COMPOSTING

Compost Marketing: AA Dairy; Composting marketing has been increasingly successful. This has occurred over time with repeat customers, word of mouth advertising and the use of a website. Prices vary depending on size of the purchase. All the manure solids can be sold.

Computerized Control: Watershed Agricultural Council, Inc.
Demonstrations of biodrying; The computerized control system that monitored the variable speed fans and the temperature of the piles did a good job of both controlling the operation and recording the data. Thermocouples in the piles were used with a logic system that could be adjusted for different operating conditions were used successfully.

Management: Earthworks
Demonstration of composting service serving multiple farms; Coordinating the composting operation and farm operation can be difficult due conflicting motives and separate management. The low profit margins in both the farm and the compost markets increase the importance of good management.

Pad Types: Cornell Waste Management Institute
Evaluation and optimization of composting systems; Earthen pads tend to have more mineral matter in the compost than compost made on concrete pads.

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SITE CONSIDERATION

Drying: Watershed Agricultural Council, Inc.
Demonstrations of biodrying; The energy from composting and the fans were sufficient to evaporate moisture to reduce 65% moisture content manure/amendment mix to 50% partially composted material with 14 days of controlled aeration and one week of fan drying.

Placement Area: Earthworks
Demonstration of composting service serving multiple farms; Soil stabilization over a large area (although cheaper than concrete) is still significant. Since composting requires access to the site for placement of the material mixing and collection an all weather surface is important to avoid ruts and added mineral matter to the compost.

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ENVIRONMENTAL ISSUES OF COMPOSTING

Ammonia: Earthworks
Demonstration of composting service serving multiple farms; Ammonia release from high nitrogen chicken manure during composting can be significant. Composting at a low carbon to nitrogen ratio will cause nitrogen loss as ammonia. To conserve nitrogen the C: N ratio should be above 40. Drying without complete composting can result in high nitrogen levels in the resulting product.

Organic Status: Kreher's Poultry Farms
Poultry waste drying and composting demonstration; Value added by certification of organic status, pathogen reduction, and processing (pelletizer) helps make the manure management profitable. Documenting the pathogen reduction during composting, certifying and marketing the dried manure as organic and processing and blending the pelletized manure helped meet their customers’ needs and enabled them to charge a higher price for their product.

Pathogens: Cornell Waste Management Institute
Evaluation and optimization of composting systems; Pathogen control varies from site to site. This is probably due to recontamination of the compost. Storage and handling methods vary from site to site.

Pathogens: Watershed Agricultural Council, Inc.
Demonstrations of biodrying; Tests involving Ascris worms successfully showed that the biodrying method killed pathogens aver a four-day period even with out mixing. The Ascris eggs were placed in a number of locations in an actively composting pile. After removal at four days the eggs were no longer viable. Control Ascris eggs were still viable. The Ascris eggs are often used to simulate the survival of Cryptosporisium oocycts.

Solids vs. Liquids: Kreher's Poultry Farms
Poultry waste drying and composting demonstration; Handling chicken manure as a solid instead of as a liquid has significant advantages in odor control and reduced volume of material. Previously liquid manure was scraped and flushed to a holding pond and then land applied. Adopting the composting system eliminated odors, flies and runoff concerns.

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MARKETING

Compost Marketing: AA Dairy; Composting marketing has been increasingly successful. This has occurred over time with repeat customers, word of mouth advertising and the use of a website. Prices vary depending on size of the purchase. All the manure solids can be sold.

Compost Marketing Standards: Cornell Waste Management Institute
Evaluation and optimization of composting systems; The production of compost on-farm results in varying quality over a range of characteristics. The C: N ratio, nutrient content, maturity, organic content, moisture content, and pathogen control vary from site to site. There are a variety of standards that compost or soil amendment could be marketed under. The varying quality of the compost and the differing standards (and no standards) in the marketplace make marketing the compost problematic.

Organic Status: Kreher's Poultry Farms
Poultry waste drying and composting demonstration; Value added by certification of organic status, pathogen reduction, and processing (pelletizer) helps make the manure management profitable. Documenting the pathogen reduction during composting, certifying and marketing the dried manure as organic and processing and blending the pelletized manure helped meet their customers’ needs and enabled them to charge a higher price for their product.

Pathogens: Cornell Waste Management Institute
Evaluation and optimization of composting systems; Pathogen control varies from site to site. This is probably due to recontamination of the compost. Storage and handling methods vary from site to site.

Pathogens: Watershed Agricultural Council, Inc.
Demonstrations of biodrying; Tests involving Ascris worms successfully showed that the biodrying method killed pathogens aver a four-day period even with out mixing. The Ascris eggs were placed in a number of locations in an actively composting pile. After removal at four days the eggs were no longer viable. Control Ascris eggs were still viable. The Ascris eggs are often used to simulate the survival of Cryptosporisium oocycts.

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