Each season, Vietnamese agriculture generates enormous volumes of by-products such as straw, husk, bagasse and manure. Instead of being burned or dumped, these can become valuable resources by applying circular-economy thinking.
What is a circular economy in agriculture?
A circular economy is a model in which the waste of one process becomes the input of another, forming closed loops rather than a linear extract-and-discard model. In agriculture, this means extracting maximum value from every by-product, cutting pollution while creating economic value from what was once discarded.
Main by-product streams and their uses
- Straw: mushroom growing, livestock feed, composting or biochar
- Husk and sawdust: fuel, growing media, husk charcoal
- Manure: composting or biogas production
- Bagasse and coffee husk: organic fertilizer or biomass fuel
Biogas and compost: classic loops
Manure and organic by-products can be fed into biogas digesters to produce gas for cooking and power, while the residual slurry becomes nutrient-rich organic fertilizer. Composting straw and manure also yields quality organic fertilizer that improves soil and reduces chemical-fertilizer dependence, closing the nutrient loop on the farm.
Environmental and economic benefits
- Less pollution from straw burning and indiscriminate dumping
- Lower greenhouse-gas emissions from decomposing by-products
- Extra income from recycled products
- Lower input costs by producing fertilizer and energy on-farm
In circular agriculture there is no such thing as waste, only resources in the wrong place; every by-product can become an input for a new value loop.
The modern VAC model and directions
Value chains from by-products
The circular economy goes beyond on-farm reuse; by-products can seed new value chains. Straw, husk and bagasse can supply fertilizer, biomass energy, materials and mushroom industries.
- Produce organic fertilizer and growing media
- Make biomass pellets for fuel
- Grow mushrooms from straw and sawdust
These chains create rural jobs, raise farmer incomes and ease the environmental pressure of burning residues.
Policy and conditions for scaling
Sustainable growth needs incentives for collecting and processing by-products and links between farmers and recyclers. Suitable logistics and processing technology are decisive for scaling. When by-products have stable markets and clear value, farmers shift from burning to collecting and reusing, helping build a greener, lower-emission agriculture.
Vietnam's traditional garden-pond-livestock (VAC) model is essentially a small-scale circular economy, where livestock waste feeds fish and fertilizes crops. Today it is being upgraded with modern treatment technology for greater efficiency and scale. ASTRI Institute views the agricultural circular economy as a research, application and technology-transfer direction of lasting significance, aiming to develop solutions for by-product use, waste treatment and organic-fertilizer production toward a green, circular and sustainable agriculture.