What are the most innovative ways to use waste as a resource for energy and materials?

Using crop residue like rice, cotton, wheat, sugarcane, corn web and municipal biowaste for domestic and commercial energy generation.

Recycling and reuse are key to success. It would be best if it could be done at the sources that can also reduce the cost. Renewable energy and biogas can play a key role in establishing sustainable objectives.

Biogas production from manure and other organics, with nutrient recovery in an on-farm biorefinery, can directly impact at least 12 of the 17 UN SDGs. Environmental impact mitigation hits air, soil and water on both the fuel (RNG) and fertilizer sides. Revenue diversification for farms supports food security, and the technologies that are present and emerging open high quality job opportunities. I don't think there is a better way to utilize "waste" resources. This is a standing opportunity for North America that is already mature in Europe and Scandinavia. Our gas utilities are aggressively seeking new supply!

Organic wastes can be safely converted to biogas that in turn can be used to generate energy for heat or cooking. This is already widely used in third-world countries.

For decades, the Los Angeles County Sanitation Districts have been anaerobically digesting biosolids from its wastewater treatment process and using the resulting methane production to generate electricity. Their digesters had extra capacity, so they are now augmenting the digester feed with slurried commercial food waste, which not only increases methane production, but has the additional benefit of diverting solid waste from landfills. An expanded gas treatment facility further refines the methane for distribution at an on-site CNG fill station. As before, the digested, dewatered biosolids are composted to produce soil amendment.

We all know the importance of waste reduction. However, the first step for proper utilization of waste is to segregate it based on its properties. After that, we should identify the best way to use the waste, which might not always mean making energy. We must consider whether anything can be recycled, used again, or transformed into something new to ensure optimal usage. If waste to energy is the best option, we should make sure to get the most energy out of it. This means preparing the waste first, for instance, by taking out moisture. And burning it in the right way using special control, like incineration in the cement industry, and mixing the ash it produces with cement without affecting its quality.

Waste-to-energy plants are designed to solve not only the disposal problem of all type of waste but also to generate useful and beneficial products from it. Its an amazing concept to cater the waste handling.

In numerous developing countries, the daily generation of waste poses a significant challenge, leading to vast landfill areas burdened with segregated and unsegregated wastes. A primary issue contributing to this situation is the inadequate availability of land for traditional landfilling practices. However, embracing the waste-to-energy principle presents a transformative solution to this problem. The potential game-changing aspect lies in the utilization of high-calorific value waste as a valuable source of fuel for steam power plants. By tapping into this resource, not only can the mountains of waste be substantially reduced, but an additional benefit emerges in the form of energy generation.

We really need to go back to 1985 and Dr. Emmet Brown's pioneering waste-to-energy work. In our constant drive for new solutions to old problems, we've forgotten that almost 40 years ago, Dr. Brown was able to produce 1.21 jigowatts for practical applications using common household waste for fuel.

Waste to Energy plants are critical, an alternative to land filling with added advantage of Energy recovery. But every thing should not end to Waste to Energy plants or landfill. Avoiding mixing of waste should be the aim.

The production of bioplastices from biomass is of critical significance and is seen by many as the future for a world relying less upon fossil fuels. Currently, the technologies of gasification and pyrolysis (both require "cooking" biomass in an oxygen free environment), produce gaseous, liquid, and solid bi-products. The solids include bio-char and ash, the liquids include bio-oils and wood vinegar, and the gaseous is called "syngas" which is high in hydrogen content. The liquid outputs can be considered as natural "crude oil", i.e. a good source of long chain organic molecules, from which bio-plastics, fibers, lubricants, fertilizers, sealants, adhesives, bitumen, paints, and pharmaceuticals can all be derived.

Bioplastics derived from biomass, such as plant starch or sugarcane, offer a sustainable alternative to traditional fossil-based plastics. As the global demand for plastics rises, transitioning to bioplastics becomes crucial for reducing environmental impact. These biomaterials are renewable, biodegradable, and have lower carbon footprints. Encouraging the adoption of bioplastics in various industries can significantly contribute to a circular economy, minimizing dependence on finite fossil resources and mitigating plastic pollution. Policymakers, industries, and consumers must collaborate to drive the widespread use of bioplastics and advance a more sustainable and eco-friendly plastic future.

One of the most intriguing bioplastics projects I remember seeing a while ago is that from Egypt where researchers were looking at developing an alternative to plastic bags using the shells from prawn/shrimp based on the polymer that is found within the shells; chitosan. I have seen a few chitosan-based bags but unfortunately they are nothing mainstream of mass produced yet. But this is just one example of how the solutions for our waste problem may lie in our waste itself.

El plástico es un mal necesario, para minimizar el impacto causado por esto debemos dirigir la mira a la innovación, los bioplasticos son una opción que aporta a la reducción de la huella ambiental.

Bioplastic does not mean Bio-degradable. Biodegradable does not mean environmentally innocuous. Bioplastics are more than anything, a source of confusion and an opportunity for greenwashing. Exactly, as this summary shows. "Can have similar properties", "can reduce reliance" "can be compostable under certain conditions" - Coca-Cola's bioplastic is not biodegradable, whereas Naturework's PLA is compostable under certain conditions, it doesn't mean it can be "littered".

Biomimicry has transformed the concept of waste from a burden into a wellspring of inspiration. By harnessing nature's ingenious solutions, it enables the creation of sustainable designs and technologies. Nature's closed-loop systems, where one organism's waste becomes nourishment for another, exemplify this beautifully. Take, for instance, the decomposition of leaves on the forest floor, fostering fertility within the ecosystem. Additionally, utilizing bacterial cellulose sourced from food waste to craft materials akin to spider silk, finds application in textiles, biomedicine, and construction, showcasing the potential of biomimicry.

Biomimicry has enlightened us that “Nothing is Waste”, therefore, waste must seen be as a “Misplaced Resource” and be utilized in a comprehensive. However, comprehensively utilizing waste may not be easier, therefore, we have to do a critical analysis of all possible ways & means of utilizing waste in terms of efficacy, economy and easiness etc in given conditions, and the best one is to be engineered effectively to adopt.

One more example of biomimetic material in environmental engineering applications is biomimetic membranes for water purification

Una alternativa sostenible y desafiante, aún falta mucho por investigar e implementar. Sin embargo, es la que mejor se puede acoplar a las necesidades de cada tipo de residuo. El reto es la innovación para lograr que todo se reintegre nuevamente a la naturaleza y/o los ciclos productivos por procesos de desintegración, descomposición, generando el menor impacto y mayor eficiencia. Por ejemplo las bacterias son capaces de degradar el petróleo, y algunos de sus derivados entre ellos plásticos son uno de los mayores problemas actuales. Por ello lograr imitar la resiliencia de la naturaleza para autoregularse y regenerarse en la disposición final de residuos logrando aprovechar la energía residual sería el mejor desarrollo.

Regenerative plastics technologies where key equipment can be produced from carbon composite based plastics are now reality and they make society movement from Iron Age to plastics age not only possible but also consistent with the human strive for circular economy where plastic products are 3-D printed onsite and when expire grind into chips that can then be used to print new products.

As Margarida brought up, brine mining is a good example of application of circular economy in desalination practices. Another one is recycling municipal wastewater ( with RO, as advanced treatment after tertiary treatment) and use the treated water for indirect or direct potable use. Another example is recovering nitrogen and phosphorous ( instead of removing through BNR processes) from municipal wastewater, through processes such as struvite crystallization....

The circular economy emphasises a comprehensive approach to resource management. It encourages a regenerative system in which things are built to last and resources are reused, recycled, or repurposed on a regular basis. The emphasis swings away from the linear "take, make, dispose" model and towards a closed-loop system that reduces waste and environmental effect. In the circular economy, systems thinking considers interconnected components such as product design, material flows, and waste management, recognising their interconnectedness. To develop a sustainable, resilient, and environmentally sensitive economic system, collaboration across industries, governmental improvements, and a shift in consumer behaviour are required.

The bio-economy is seen as an important goal for proponents of the circular economy concept. Whilst the "circular economy" is rightly seen as a highly significant concept in terms of "climate change" and natural resource depletion, when it is paired up with the concept of the "bio-economy" it is also seen as a critical part of the solution to nature regeneration, and "nature positive".

Civil construction projects could play a central role in the push for a circular economy, and the Envision framework identifies opportunities and best practices to incorporate circular economy practices into project planning and implementation. Envision credits focused on completing a Life-Cycle evaluation, using recycled materials, and reducing construction and operational waste can help engineers and planners put circular economy into context of full project development and implementation, going beyond construction and considering how civil works can be improved to promote sustainability.

We currently live in world where the climate debate is highly focused upon the concept of "energy". However I believe this current concept of energy needs expanding, For example, the end point of practically all energy flows is "human consumption". Either through food or some material used as a consequence of our lifestyle. Thus, when budgeting or accounting for all energy consumption/expenditure it would be important to also consider whether the end use is sustaining a real need, or simply a temporary emotional mental state. Following this train of thought might lead to re-thinking "energy" and including concepts from the natural world, for example, the calorie, the ability to return nutrients to the soil, or clean air, or water...etc.

There is an immediate need to do reductions in carbon and GHG emissions. There are technologies available that can help in the decarbonisation of the processes that are essential but that is not enough. Today an honest effort is required to plant more and more trees which are real sinks for carbon and also society needs to be more conscious of their carbon footprint.

Why do we continue to completely ignore that plant residuals and municipal organic solid wastes are captured carbon? Instead of building an entire new infrastructure to remove carbon from the atmosphere, how about using what the plants have done for us for free. If we take these wastes and sequester them directly we will remove carbon from the atmosphere. Instead, we only use methods that completely return the carbon to the atmosphere. Even if you get energy or new soil (composting) you are still warming the planet by putting the carbon back into the atmosphere.

70% of domestic solid waste in the US is biomass. 600 million tons of carbon dioxide removed from the atmosphere and made into useful products every year. The problem is that we return 100% of that carbon to the atmosphere through burning (renewable fuel), burying (landfill), or composting. There are natural ways to take that biomass and sequester it. Why have we given a pass to the solid waste industry? Every other industry is being forced to come up with new practices to lower their carbon footprint. Yet we let the solid waste industry get away with using technology that was developed over 100-200 years ago. Let’s sequester the carbon we capture on a daily basis before we spend $trillions on capturing new carbon.

Instead of focusing on reusing waste, why not focus on reducing waste? Let’s optimize processes to be more efficient and consume less.