Sustainable Piggery Waste Management: A Study Based on Examples and Cases from Denmark and Thailand
In the global pursuit of a more sustainable agricultural future, the management of waste from pig farming has emerged as a critical challenge and a remarkable opportunity. This article explores how two geographically and economically distinct nations—Denmark, a European leader in green technology, and Thailand, a dynamic agricultural economy in Southeast Asia—are transforming pig waste from an environmental liability into a valuable resource, pioneering a path toward a circular economy in the pork industry.
On average, a single pig can produce an amount of waste equivalent to 1-2% of its body weight every day4 . For a large farm, this translates into hundreds of kilograms of waste daily.
When stored in open lagoons or over-applied to fields, pig manure releases methane, a potent greenhouse gas with a global warming potential 21 times greater than carbon dioxide9 .
Manure can contaminate water bodies with excess nutrients like nitrogen and phosphorus, leading to algal blooms that deplete oxygen and harm aquatic life1 .
Improperly handled waste poses biosecurity risks by potentially spreading pathogens such as Salmonella and E. coli4 .
Technological Precision and System Integration
Denmark has established itself as a global frontrunner in sustainable waste management, with a market valued at USD 17.17 billion in 2024 and a clear trajectory toward advanced circular economy practices8 .
Iconic facilities like Copenhagen's Amager Bakke (CopenHill) exemplify this—not only is it a highly efficient waste incineration plant, but it also doubles as a public recreational space with a ski slope on its roof8 .
With approximately 50 biogas plants, including some of the most significant in Europe, the country effectively transforms pig slurry into renewable energy7 .
The Danish government supports this through robust regulatory frameworks, including a mandatory Extended Producer Responsibility (EPR) scheme for single-use plastics8 .
The success of this model is visible in projects like the Kalundborg Eco-Industrial Park, where surplus heat and by-products are repurposed for use by nearby companies8 .
Practical Innovation and Community Empowerment
Thailand's approach showcases remarkable innovation and a strong focus on community benefits. In Thailand, where agriculture accounts for 14% of greenhouse gas emissions and is the leading source of methane, traditional waste treatment methods present significant challenges9 .
This program by CPF Swine Business creates four valuable resources from what was previously considered waste, winning top honors at the CPF Sustainability in Action Awards 20246 .
From biomass incinerators is repurposed as a bacterial control agent, saving farmers over 300,000 baht annually per farm6 .
Provides biogas from swine farms to over 30 households. A local resident reports, "Since connecting to the biogas system, our cooking gas cylinders last up to 4-5 months instead of 1-2 months"6 .
Transforms biogas system sediment into premium organic fertiliser, cutting production costs for farmers by more than half6 .
The core technology enabling this waste transformation in both Denmark and Thailand is anaerobic digestion.
Pig manure and urine are collected from barns, often using slatted floors that allow waste to pass into collection channels below4 5 .
The collected waste is fed into an air-tight, oxygen-free tank called an anaerobic digester5 9 .
Inside the digester, bacteria break down the organic matter. This process, which typically takes a few weeks, produces two main by-products:
The biogas is combusted in a generator to produce electricity and heat9 . This renewable energy can power farm operations, significantly reducing reliance on the fossil-fuel-based grid. The digestate is then separated into liquid and solid fractions, which can be used as a potent organic fertilizer5 7 .
| Aspect | Denmark | Thailand |
|---|---|---|
| Primary Driver | Regulatory frameworks & technological innovation | Cost savings & community development |
| Key Technology | Large-scale anaerobic digestion & waste-to-energy | Closed anaerobic systems & biomass repurposing |
| Energy Output | Biogas for electricity & district heating networks7 8 | Biogas for on-farm use & local community cooking gas6 9 |
| Agricultural Co-product | Refined biofertilizers from digestate7 | "Good Sludge" fertilizer & "Good Fertiliser Water"6 |
| Community Impact | Industrial symbiosis & reduced national emissions8 | Direct cost savings for farmers & local energy access6 |
The revolution in pig waste management is powered by a suite of technologies that convert raw manure into valuable resources.
Uses natural media to filter and biologically degrade pollutants from barn air5 .
Separates solid and liquid fractions of slurry for more efficient processing7 .
Impermeable liner prevents groundwater contamination; cover captures gases and reduces odor1 .
The journeys of Denmark and Thailand demonstrate that sustainable pig waste management is not a one-size-fits-all model but a adaptable set of principles centered on the circular economy. While Denmark leverages high-tech integration and stringent regulations, Thailand excels in creating cost-effective, community-centric solutions. Both, however, share a common goal: viewing waste not as a problem to be disposed of, but as a resource to be harnessed.
By converting methane into energy, nutrients into fertilizer, and costs into savings, these innovative strategies offer a blueprint for the global swine industry. They prove that environmental stewardship can go hand-in-hand with economic viability, paving the way for a future where farming sustains both the planet and its people.