Linear economy vs circular economy:

1- Linear Economy:

The economic model human beings have been using up until now is “linear”, where raw resources are extracted, processed, consumed, and turned into waste. The waste generated is disposed of at some landfill and is lost forever.

Since our planet Earth has only limited natural resources, human beings cannot afford to practice this economic model for long. It is because this model cannot provide critical non-renewable resources to the resource-hungry industries, indefinitely. Not only that, linear economy also creates several other problems too, with Biodiversity and Climate Change being the most significant ones.

2- Circular Economy:

The circular economy is the model of economy that attempts to mimic natural ecosystems to make the life cycle of any product, circular or close-looped. The natural model works in such a way that the waste generated from one system works as the raw material for the other system and the waste from the second system works as raw material for the third system and so on.

This way nature ensures minimal to zero production of such a waste that can not be used by any system. The circular model targets efficient resource consumption, enhanced resource recovery, and minimal generation of waste products.

Innovative Concepts in wastewater treatment plant

The essence of a circular economy is efficient resource consumption and waste reduction. Biological wastewater treatment plants play a pivotal role in this regard in pushing the agenda of a circular, more sustainable, economy. Wastewater treatment plants contribute towards a circular economy in several ways.

1-Recycling treated wastewater: Sustainable water management

The proportion of water that is fit for human consumption is already very small. When we use this water in an unsustainable way following a linear economic model, we are left with an even smaller percentage of the already scarce critical resource, every passing day.

Biological wastewater treatment plants help make this linear system sustainable. The treated wastewater can be reused for several purposes, i.e., horticulture, flushing, agriculture, groundwater replenishment etc. Adopting this model helps create a balance between the consumption and conservation of water resources helping in reducing the load on fresh water resources.

The EU’s Water Framework Directive has demanded the member states to implement steps to conserve the water resources. Techniques like home-level, and decentralized wastewater treatment plants have caught the undivided attention of European households as one of the most viable options to ensure compliance with such directives.

2-Conserving biodiversity

Biological wastewater treatment also plays a key role in protecting biodiversity and ecosystems, which is one of the objectives of the European Union’s Biodiversity Strategy for 2030. When we do not treat our wastewater and let it discharge into natural water bodies and streams it causes havoc in those systems. The decomposition of highly concentrated organic waste causes dead zones (zones that are deprived of oxygen) in the water bodies that cause the fish and other species to die off. Depending upon the exact configuration of the discharged wastewater, eutrophication can also occur, which disturbs the aquatic ecosystem in similar ways.

Biological wastewater treatment plants help resolve this issue by decomposing the harmful pollutants in wastewater. The harmful pollutants are converted into beneficial biomass that further treats the wastewater. This way the treated wastewater, free from any harmful chemicals, is then safely discharged into natural water streams and lakes, where it supports the aquatic ecosystem.

3-Cutting down Green House Gas emissions

Traditionally, wastewater treatment plants relied on chemicals and energy-intensive processes to treat wastewater. This released a large amount of Green greenhouse gasses (GHGs) mainly CO2 into the atmosphere. Advancements in biological wastewater treatment technologies i.e., An-aerobic wastewater treatment and decentralized wastewater technologies promise the reduction of energy demands of wastewater treatment plants and resulting in a significant reduction in the GHG emissions.

Especially European countries, which face strict climate targets set by the European Green Deal. This is the second of the two examples, where innovations in biological wastewater treatment help not only practice circular economy but also solve the issue of climate change.

4-Nutrient’s recovery

Another contribution of biological wastewater treatment plant is the recovery of essential nutrients, especially Nitrogen and phosphorus from domestic wastewater or larger biological wastewater facilities. These nutrients play an important role in improved agricultural yields.

With the advent of Anaerobic digestion, a technique used in biological wastewater treatment, the recovery of Nitrogen and phosphorus has been further improved. This will help countries make their own essential nutrients to support horticultural or local agriculture rather than relying heavily on other countries. The Netherlands, for example, is currently using this opportunity to create Phosphorus from wastewater, further reducing the production of waste.

5-Biogas production

Another way in which wastewater treatment helps in transitioning towards a circular economy is the production of energy-rich, renewable gas, called biogas. The anaerobic treatment of the wastewater oxidizes the organic contamination of biological wastewater and turns it into biogas, under strictly controlled conditions. This gas can then be used either for heating purposes in homes or generating electricity.

Germany, for example, is pioneering the use of biogas, produced during wastewater treatment, to power the treatment facilities themselves. Innovatively solving an energy problem with the waste problem. This helps the country in moving closer to its goal of becoming carbon neutral in 2050.

Conclusion:

Biological wastewater treatment is a technique used not only for wastewater treatment but also extracts valuable resources i.e., nutrients, biogas, etc., helps reduce pressure on finite freshwater resources, and conserves biodiversity. This way biological wastewater treatment contributes to transitioning towards a more sustainable, circular model of economy.

As the world is currently committed to mitigating the impacts of climate change and preserving the natural environment, biological wastewater treatment plants will play an increasingly crucial role in achieving these targets.

Frequently Ask Questions