In the traditional industrial approach, each factory is often seen as an isolated "island": it sources its own raw materials, produces its own products, and handles its own waste. This results in high operating costs, significant environmental pressure, and makes it very difficult to approach a circular economy.
Conversely, the industrial symbiosis model views the industrial park as an ecosystem. There, the flow of materials and energy is designed to circulate between businesses: by-products, waste, excess heat, and treated water from one business become input resources for another. This is a crucial foundation of the eco-industrial park that UNIDO, the World Bank, and many countries are promoting.
This article focuses on clarifying: what the industrial symbiosis model is, what forms it takes, what core components it includes, and how to begin implementing it in the Vietnamese context.
1. The concept of the industrial symbiosis model
Industrial symbiosis is a deliberate collaboration between businesses within the same industrial park, cluster, or neighboring area. Instead of completely processing or disposing of waste, the parties:
- Sharing and exchanging flows of materials, energy, water, and byproducts.
- Shared processing infrastructure
- Coordinate efforts to optimize resource efficiency and reduce environmental impact.
According to the definition in documents on eco-industrial parks, industrial symbiosis is a method that helps businesses gain a competitive advantage through the exchange of materials, energy, water, and by-products, thereby simultaneously improving economic, environmental, and social efficiency.
Thus, the industrial symbiosis model can be understood as the way in which these linkages are organized, designed, and operated within an industrial park or industrial zone, including:
- Structure of participating businesses
- Type of resource flow being exchanged
- Infrastructure and supporting technologies
- Governance mechanisms, policies, and cooperation models
2. Typical forms of industrial symbiosis models
In international practice, several forms of industrial symbiosis models are commonly mentioned.
2.1. Spontaneous (self-organizing) symbiosis model
This is a typical example of the Kalundborg Symbiosis in Denmark, considered the oldest and most classic example of industrial symbiosis in the world. Featured:
- Symbiotic networks gradually form over time, stemming from very real economic needs between neighboring businesses.
- Each link in the exchange of materials and energy is a specific "business agreement," formed only when it benefits all parties involved.
- The role of the government and regulatory agencies is primarily to support and facilitate, not to impose.
Advantages: flexible, closely aligned with market needs, and highly sustainable once operations are stable.
Limitations: difficult to scale quickly, heavily dependent on the trust and networking capabilities of the business.
2.2. Planned symbiotic model (associated with eco-industrial parks)
This is a model that is being encouraged by many countries and international organizations such as UNIDO, the World Bank, and GIZ through the Eco-Industrial Park (EIP) framework.
Featured:
- The industrial park was planned from the outset with an ecological vision: centralized wastewater treatment infrastructure, heating system, water reuse, and shared waste collection.
- Industrial symbiosis is considered a design objective: industrial park developers proactively attract suitable industries, arrange locations and infrastructure to enhance the exchange of resource flows.
- There are sets of criteria, standards, and assessment tools (e.g., the international EIP framework and national indicator sets) for implementation and monitoring.
Advantages: easy to integrate into development and planning strategies, and can mobilize support resources from international programs and development banks.
Limitation: If the model is only "designed on paper" without economic incentives for the business, it can easily become merely a formality.
2.3. Industry- or value chain-based symbiotic models
Some models focus on specific industries or value chains, for example:
- The steel industrial park shares byproducts such as slag, furnace dust, and waste heat with the building materials, cement, and energy industries.
- The agro-food chain links raw material sources to processing, by-products for animal feed, organic fertilizers, and bioenergy.
This type of model leverages in-depth knowledge of an industry's processes and by-products, thereby enabling the design of more suitable and manageable symbiotic relationships.
3. The core components of an industrial symbiosis model
Whether spontaneous or planned, an effective industrial symbiosis system typically has the following key components:
3.1. Business structure and flow of goods and services
- A group of businesses whose industries have the capacity to generate and utilize by-products, waste, surplus energy, and treated wastewater.
- Detailed map of material and energy flows: sources, volume, composition, frequency, and potential demand.
Studies on eco-industrial parks show that mapping resource flows is a crucial first step in identifying symbiotic opportunities and designing appropriate models.
3.2. Infrastructure and supporting technologies
- The system includes shared pipelines, tanks, pumping stations, heat exchangers, wastewater treatment plants, and waste and byproduct transfer warehouses.
- Technology for processing, cleaning, and transforming by-products to meet the technical standards of the recipient.
- A digital platform for measuring, monitoring, and tracking resource and environmental flows in real time.
According to the international EIP framework, shared infrastructure and resource-efficient solutions – cleaner production – are the pillars of eco-industrial parks.
3.3. Governance Model and Cooperation Mechanism
- The role of investors and industrial park management in leading and coordinating symbiotic opportunities.
- The contractual mechanism, pricing, and the distribution of costs and benefits among participating businesses.
- Procedures for resolving disputes, sharing data, and protecting commercial information.
3.4. Legal framework and incentive policies
- Clear regulations on byproduct recognition, waste reuse, byproduct standards, and environmental responsibility.
- Preferential policies, financial support, green credit, tax and fee incentives for symbiotic infrastructure projects and participating businesses.
- Technical assistance programs and guidance from regulatory agencies and international organizations.
In Vietnam, pilot eco-industrial park projects have shown that with well-structured policies and support projects, the number of proposed and implemented symbiotic solutions increases significantly.
4. Suggestions for building an industrial symbiosis model in the Vietnamese context.
For investors and businesses in industrial parks in Vietnam, the following steps can be considered when approaching the development of an industrial symbiosis model:
First, assess the current state and potential for symbiosis.
- Collect data on the flow of raw materials, by-products, waste, energy, and water for each enterprise in the industrial park.
- Utilize assessment frameworks and tools provided by UNIDO, the World Bank, and EIP development assistance projects to identify highly viable symbiotic opportunities.
Secondly, choose a model that suits the context.
- If the industrial park has been established for a long time and has many diverse businesses, a more spontaneous, yet technically supported, approach is preferred, with a stronger "connecting" role from the management.
- If it is a new industrial park or one undergoing expansion: immediately integrate the principles of ecological industrial parks, infrastructure planning, and industry structure to facilitate symbiosis.
Third, pilot small but "measurable" models.
- Start with a few resource streams that are large in volume and easy to measure, such as waste heat, fly ash, organic sludge, and treated wastewater.
- The pilot project design includes clear indicators of cost savings, byproduct revenue, and reductions in waste and emissions.
Fourth, gradually institutionalize and scale up the process.
- Following the pilot phase, incorporate requirements and incentives for symbiosis into the industrial park's operational regulations, as well as criteria for selecting and evaluating secondary investors.
- Integrate the industrial symbiosis model with the local, city, or region's circular economy strategy to leverage resources and support mechanisms.
Conclusion
The industrial symbiosis model is not just an academic idea; it has been proven through many international examples such as Kalundborg, as well as eco-industrial park projects currently being implemented in Vietnam. The essence of this model is to redesign how we use resources and handle waste in industrial parks, shifting from a "each factory does its own thing" mindset to an ecosystem-based thinking, sharing benefits and responsibilities.