Good Practice - Project
Biochar for reduced emissions of ammonia and greenhouse gases on a beef farm with biogas
Biochar research findings from Swedish beef industry research
General information
RDP Priority
- P5. Resource efficiency and climate
RDP Focus Area
- 5D: Greenhouse gas & ammonia emissions
RDP Measure
- M16: Cooperation
Summary
The pilot study aimed at investigating whether biochar applied in deep litter systems could have the effect of reducing the emissions of ammonia and greenhouse gases on beef farms. This was combined with an investigation as to how biochar could positively affect the amount of biogas produced on-farm.
The project was tasked to develop benchmarks and recommendations for the Swedish beef production industry within the parameters of maintaining adequate levels of economic competitiveness, while taking into account climate change and animal welfare.
The collaborative study team incorporated partners with different competences conducting the various project activities. These included taking measurements of ammonia and greenhouse gases, keeping logs of the well-being of the animals, monitoring and testing of the biogas production, conducting the economic analysis and developing recommendations.
Results
The pilot study produced the following results:
- The economic analysis showed that the costs of purchasing and handling biochar exceeded the income generated from the increase in energy production, additional carbon storage and reduced ammonia emissions. The application of biochar in deep litter systems was, therefore, not recommended as an economic option for the beef production industry at the time of the study.
- Biochar reduced the ammonia release in deep litter systems by 25%.
- No further reduction of the ammonia emissions could be achieved via double dosing.
- The measurements varied substantially.
- It was not possible to draw any robust conclusions regarding the effect of biochar on greenhouse gas emissions due to variations in measurements.
- The daily production of biogas increased when applying 0.5 kg of biochar (specifically for methane by 21%).
- Animal health aspects were not affected using biochar.
Promoter
Hushållningssällskapet Sjuhärad
Funding
Total budget 870 155 (SEK)
EAFRD 317 951 (SEK)
National/Regional 465 179 (SEK)
Private/Own funds 77 445 (SEK)
Other funding sources 9 580 (SEK)*
* Contributions by AKEMA AB and Emåmejerier
Ressources
EU CAP Network - Good Practice - Biochar for reduced emissions of ammonia and greenhouse gases on a beef farm with biogas
(PDF – 529.47 Ko)
Context
Biochar is a carbon-rich, solid material produced from biomass. It is generally used for soil improvement whereby it helps increase the water or nutrient-holding capacity of the soil and biochar can also be used as a carbon sink.
To further explore its uses and effects, a research project was designed to build knowledge on how biochar might affect the emissions of ammonia and other greenhouse gases when used in deep litter systems. Deep litter systems represent a method of waste management in livestock buildings relying on in-situ composting of the bedding material instead of regularly cleaning and replacing it. However, emissions of ammonia and other greenhouse gases can be an issue with this approach and the project sought to investigate whether biochar could be a way of reducing these in the particular context of beef production.
Very few studies had been undertaken on this topic, and the research team at Hushållningssällskapet Sjuhärad (an independent knowledge organisation undertaking research and sharing knowledge with rural businesses and agricultural entrepreneurs in Sjuhärad in south west Sweden) was keen to add knowledge in this area by conducting a pilot study.
Objectives
The pilot study aimed at investigating whether biochar applied in deep litter systems could have an effect on the emissions of ammonia and greenhouse gases. This was combined with an investigation as to how biochar could affect the amount of biogas produced on-farm from beef production.
The project was tasked to create a basis and benchmarks for any future utilisation of biochar in deep bedding approaches including the digestion of deep bedding treated with biochar to reduce the emission of ammonia and greenhouse gases. The study was further expected to develop recommendations for the Swedish beef production industry within the parameters of maintaining adequate levels of economic competitiveness, while taking into account climate change and animal welfare.
Activities
The project incorporated the following key activities:
- Taking measurements of ammonia and greenhouse gases involving:
- Three groups of 12 young bulls per group between October 2018 and March 2019
- One group without biochar in the deep litter bed was compared with two groups with biochar in the deep litter beds. One of them with 2.5% biochar and the other one with 5% biochar.
- Biochar was spread by hand, watered and then covered with wheat straw. Measurements were taken in different sections of the boxes to ensure a representative coverage.
- Monitoring livestock well-being (growth, time lying in the deep litter bed, cleanliness and behaviour).
- Monitoring and testing of the biogas production:
- Deep litter with and without biochar was tested as a substrate for biogas production.
- Continuous reactors for measurement of total gas production and specific methane production.
- Three reactors were each fed with their substrate and the volume was adjusted with water.
- The loading rate was three g VS (organic matter) per litre and day and the experiment was carried out for three 30-day dismantling times.
- Conducting an economic analysis:
- Calculations were performed based on the experimental results to estimate the added value of using biochar in deep bedding and in biogas production.
Main results
The pilot study produced the following results:
Regarding the effect of biochar on ammonia emissions, it was found that:
- Biochar reduced the ammonia release when adding 2.5% biochar of the amount of manure in the deep litter system.
- The ammonia emissions reduced by 25%. However, this varied over time.
- No further reduction of the ammonia emissions could be achieved via double dosing.
- The measurements varied substantially.
Regarding the effect of biochar on greenhouse gas emissions:
- Due to significant variations in measurement, it was not possible to draw any robust conclusions from the results about how the greenhouse gases were affected by the addition of biochar in deep litter beds.
Regarding the production of biogas:
- The daily production of biogas increased when applying 0.5 kg of biochar. The specific methane production rose by 21%.
Regarding animal health impacts:
- No adverse health impacts were recorded using biochar.
Regarding the economic viability of applying biochar:
- The economic analysis showed that the costs of purchasing and handling biochar exceeded the income generated from the increase in energy production, additional carbon storage and reduced ammonia emissions. The application of biochar in deep litter systems was, therefore, not recommended as an economic option for the beef production industry at the time of the study.
Key lessons and recommendations
- Temperatures both outdoors and indoors affected the measurement results.
- Spreading the biochar in the stables manually was hard work and created a lot of dust. To solve the dust issue, it became essential to water the biochar. This was an important experience. If this would had been known beforehand, the performance of the task would have been easier.
- The dismantling times in biogas production could have been extended from 30 to 50 days to extract more biogas from the organic material.
- The project’s economic calculations showed that biochar would first need to come down in price before making its use economically viable in deep litter systems.