The majority of plastics used in the world today come from non-renewable and non-biodegradable sources. In an effort to reduce the impact of plastics on the environment, alternative methods of production and waste management have been studied for decades. Several microorganisms have the ability to produce plastics naturally, using different substrates, which are biodegradable and biocompatible under certain conditions.
During the last few years, acidogenic fermentation for the production of volatile fatty acids (VFA) has been identified as a promising approach to utilise organic waste as a valuable resource. VFA have a wide potential for applications ranging from carbon source for biological nutrient removal processes to use as a bioenergy resource for the generation of hydrogen and liquid biofuels. VFA-rich streams produced from organic waste fermentation can also be used as biopolymer precursors in the bioplastics industry, as they are a suitable feedstock for the production of polyhydroxyalkanoates (PHA).
To address the growing problem of bio-waste generation and the increasing demand for bio-based feedstocks, the ELLIPSE project is working in the biotechnology sector with the aim of valorising heterogeneous waste streams generated in significant quantities in Europe, slaughterhouse waste (contained in the belly or rumen) and paper and pulp sludge, to produce cost-effective polyhydroxyalkanoates (PHA) for agricultural and personal care applications, through co-processing with other organic wastes such as sludge from the dairy industry and glycerol from the biodiesel industry, as well as nutrient recovery to produce bio-based fertilisers. The integration of these waste streams as biorefinery feedstocks will reduce landfill waste volumes, open up new pathways for the production of chemicals and bioplastics and, at the same time, create additional income for the related industries that generate them, with the added benefits of water recycling, reduced soil degradation, groundwater contamination and methane emissions.
PHA belongs to a family of 100% bio-based polymers with versatile biodegradability properties in most environments, recyclable and exhibiting a wide range of physical and mechanical properties depending on their chemical composition, from the very flexible poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) to the rigid polyhydroxybutyrate (PHB), showing similar properties to some fossil-based materials such as polypropylene (PP) and polyethylene (PE) and better gas and liquid barrier properties than other bioplastics such as polylactic acid (PLA), being a good biodegradable and compostable alternative in agricultural and personal care applications.
One of the objectives is to maximise the production of VFA derived from acidogenic fermentation by optimising the process using innovative technologies, such as the use of an anaerobic membrane bioreactor (AnMBR). The project contributes to the circular economy by promoting sustainability and zero waste by demonstrating the technical feasibility of recovering nutrients from the waste stream (digestate) through a hybrid autotrophic-heterotrophic process of microalgae cultivation, which results in the production of a biofertiliser.
The project has 5 phases dealing with pre-treatment of waste and obtaining VFA, production of PHA, possible applications of bioplastics, life cycle analysis study and exploitation of the results.
Pliot plants of the ELLIPSE project
In Pilot 1, pre-treatment and valorisation of sludge from the processing of slaughterhouse waste for the production of rigid packaging and plastic mulch will be carried out. A co-digestion of raw materials will be carried out in order to ensure the most optimal conditions for producing VFA.
Pilot 3 will be developed simultaneously with Pilot 1 to recover N and P nutrients for biofertiliser production. Different technologies will be validated:
The biological technology of the hybrid autotrophic and heterotrophic microalgae culture system, and the physical methods of pressure-drive membrane technology (ultrafiltration and reverse osmosis) and membrane contactors, to recover ammonia, as ammonium sulphate.
Pilot 2 will treat and recover waste from the paper industry to produce bioplastic coatings for the personal care and agricultural sectors.
The demonstration of the possibility to transform complex bio-waste stream into high-value bio-based and biodegradable products in multiple sectors, accompanied by the validation of multiple end-of life routes for the biobased and biodegradable products achieved within the project will provide novel and tangible results for further promoting public awareness and acceptance of biodegradable and bio-based solutions. Apart from all this, during ELLIPSE project the pulp and paper industry will be able to utilize products (PHA coated paper for flexible packaging as counterpart of current PE coated paper) produced from its wastes. This is a good showcase for circular economy and has the potential to increase awareness and acceptance of bio-based solutions.
Water is essential for human survival and well-being and plays an important role for many economic sectors. However, water resources are unevenly distributed in space and time, and are under pressure from human activity and economic development.
In addition to water for irrigation and food production which puts one of the greatest pressures on freshwater resources, industry is also a major water consumer, accounting for between 10% (Asia) and 57% (Europe) of total water consumption, either for the production of its products, and/or for the maintenance of its materials and equipment. All industrial sectors make use of water for industrial processes, ranging from those that manufacture foodstuffs to those that manufacture electronic devices.
Wastewater management is also one of the most important environmental problems facing society today, and is therefore an issue that transcends purely industrial activities, since as a vital substance, water is an ecosystem service that is transversal to most human activities, and whose traceability is heavily regulated by governmental and environmental agencies.
The possibility of reusing industrial water, regardless of whether the intention is to increase water supply or to manage nutrients in treated effluents (also a factor leading to water reuse), has positive benefits that are also the main motivators for the implementation of reuse programmes in companies.
Water Consumption in Industry – Management and Saving Plan
Industries can make better use of water, machinery, processes, services and accessories that demand large quantities of this resource that can be reduced with efficient use techniques.
For each type of industry, water is essential to satisfy different needs, and it is common to prioritise water consumption for cleaning and disinfection of products or installations and equipment. In these cleaning and disinfection tasks, the volume of water consumed varies according to the size, equipment and facilities, and the potential for savings is significant.
Therefore, water reuse should be examined from a circular economy perspective and the opportunities and risks of water reuse in the transition to a circular economy should be investigated for each type of industry.
The objectives of creating a water consumption management and saving plan in companies are:
Define methods to find out the water consumption in the facilities.
Identify strategies and points for improvement in the water consumption actions of the facilities and assess their feasibility.
To implement an effective system to reduce and control this water consumption.
Promote the participation of workers.
Water use in industry
The integral water cycle in industry
The transition to a circular economy encourages more efficient water use and, together with incentives for innovation, can improve an economy’s ability to cope with the demands of the growing imbalance between water supply and demand.
From a circular economy perspective, water reuse is a win-win option. The full cycle of wastewater management is a key component of the cycle, from source, through distribution, collection (sewerage and sanitation systems) and treatment to disposal and reuse, including water, nutrient and energy recovery. Circular economy initiatives aim to close resource loops and extend the useful life of resources and materials through longer use, reuse and remanufacturing.
The selective segregation-correction of segregated effluents from the different industrial activities (process water, cleaning, cooling, boilers, sanitary, etc.) favours the recirculation of water and the reuse of the company’s own treated water, as well as the reuse of grey water. It also minimises water consumption, reduces the final volume of water to be treated or managed and increases the efficiency of the final treatment process.
In general, water reuse requires physico-chemical treatment processes, connections, waste disposal mechanisms and other systems. The level of treatment will depend on the quality of water required for the proposed use.
The implementation of water management and water savings to be optimised is described by means of the 9 elements that make up the integral water cycle in industry:
Supply sources: distribution network, own wells, rainwater, etc.
Specific treatment depending on the quality requirements for the different types and uses of water.
Piping to the facilities.
Uses in the process (supply to product, reaction medium, dilution, etc.) and auxiliary activities (cooling towers, steam boilers, cleaning of equipment and facilities).
Effluent drainage.
Recirculation.
Purification (own or external WWTP).
Internal reuse.
Discharge of wastewater, quality requirement limited by the competent environmental authority.
Water consumption in industry can be rationalised and minimised through various improvements in the production process and auxiliary activities, taking as a reference the application of BATs (Best Available Techniques in relation to integrated environmental authorisations in industrial activities).
As a rule, general actions concern the modification of open cooling circuits into closed ones, the avoidance of losses in steam systems, the improvement of inlet water conditioning systems and production means, and the optimisation of cleaning operations of equipment and installations.
Recirculation is considered if water treatment is not necessary or is very simple, as it involves the successive use of a flow of water in the same process, consuming a small percentage of flow renewal in each cycle.
Internal reuse is the use of water already used in the industry itself, treated by a specific treatment, for other uses that are less demanding in terms of quality or sensitivity.
Non-conventional resources such, as rainwater harvesting, are an easy way to obtain water and do not require purification, but depends on the amount of precipitation in each location. It offers advantages such as high physico-chemical water quality without the need for purification and a simple infrastructure.
The reuse of greywater from showers and toilets with a low level of contamination can be treated into clean, non-potable water.
Operational methodology for optimising water consumption and management
The procedure is summarised as follows:
STEP 1
Data collection and analysis. Request for previous documentation and data necessary for the evaluation of water management.
STEP 2
Visit to the company to recognise “in situ” the corresponding characteristics of the production processes developed, as well as the use of water in the plant.
STEP 3
General description of the production processes and auxiliary activities, identifying the different operations: process line, water line, treatment lines and auxiliary activities (refrigeration, steam boiler, cleaning of equipment and containers and storage).
Diagram/plan of water use in the company.
Substances involved, raw materials, reagents, by-products.
Inventory and description of ancillary activities.
Inventory, origin, handling and destination of effluents, wastes and emissions.
STEP 4
Report writing:
Diagnosis of minimisation of water consumption and proposal for improvement.
Prioritisation of actions according to their performance.
Essentially, the fundamental strategy for the optimisation of water management is the global characterisation of water use, the application of selective segregation-correction of process effluents and the analysis of the possible recovery and utilisation of these effluents.
Optimising water management in industry can achieve savings of 40-50%. This can reduce costs and protect natural resources. Companies should be aware that this increases the social prestige of the company with an economic benefit and promotes sustainability.
Microalgae here, microalgae there. It is so rare not to have come across any news about the exploitation and the thousand uses of these microorganisms that a few years ago we simply knew as those that dye salty and sweet waters green.
Microalgae are a very beneficial source for humanity, extending their application to fields such as food, agriculture, aquaculture, pharmacology and cosmetics, among others. They can also generate clean energy and second-generation biofuels, thereby contributing to the development of the circular economy.
They can grow autotrophically or heterotrophic. In the first, they use sunlight as an energy source and CO2 as an inorganic source of carbon, consuming nutrients and producing oxygen. While in heterotrophic growth mode the only source of energy or carbon is organic compounds.
Heterotrophic microalgae have great potential to remove organic carbon and various types of nitrogen and phosphorous compounds from wastewater, which use it as a source of carbon and energy without the need for sunlight. It is, therefore, a great opportunity to purify wastewater without requiring large areas, as in the case of autotrophic conditions.
LIFE ALGAECAN Project
With the LIFE ALGAECAN project, coordinated by CARTIF, a new sustainable treatment of residual effluents from the agri-food industry is proposed through the cultivation of heterotrophic microalgae, obtaining a high-quality by-product as raw material and of commercial interest. This by-product aims to be useful as a biofertilizer and / or animal feed.
Microalgal biomass contains micro and macronutrients, especially nitrogen, phosphorous and potassium, which can be considered as a biofertilizer, a product that can help improve soil fertility and stimulate plant growth.
The pilot plant has been installed and operating for six months at the Huercasa company facilities, in Segovia (Spain), carrying out a treatment of its residual water from the washing and processing of vegetables and achieving the profitable growth of heterotrophic microalgae in closed tanks .
This demonstration plant is capable of carrying out a treatment of 2m3 a day through the cultivation of microalgae; a separation by centrifugation of the algal biomass and clean water and, lastly, a spray drying of this biomass obtaining microalgae powder as the final product.
Is this treatment environmentally and economically beneficial?
The project consortium has designed and developed this prototype treatment, powered by renewable energies, specifically solar energy and with the support of biomass, with the aim of minimizing the carbon footprint and operating costs.
On the other hand, an economic benefit will be obtained with the sale of the microalgae obtained as a biofertilizer.
The results obtained have been favorable so far, given that a purified water is being achieved within the legal parameters of discharges, in addition to the complete elimination of the sludge that is generated in the traditional process of purification of this type of water in conditions aerobics. This translates into a good option as a treatment for companies with this type of effluent and its possible escalation at an industrial level.
The ultimate goal of the project is to replicate its results elsewhere and for the next six months the plant will be operating in the second demonstrator at the VIPÎ company facilities in Slovenia, where the environmental conditions are different.
The project consortium is made up of the CARTIF Technology Centers (as coordinator) and AlgEn (Slovenia), the companies HUERCASA (Spain) and VIPÎ (Slovenia), and the University of Athens (Greece).
