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Novel on-line composting monitoring system

Final Report Summary - COMPO-BALL (Novel on-line composting monitoring system)


Executive Summary:

COMPOBALL was a three year applied research project, which commenced in February 2010 and finished in January 2013, and was funded under the “Research for SME-AGs” programme of the European Commission’s Seventh Framework Programme (FP7).

The Compoball project has developed a novel wireless monitoring tool to measure temperature and humidity on-line at various points of the composting material. The multiple measurements are displayed in an user-friendly web-based user interface that the operator can consult on-line in order to make any management decisions. Currently temperature can be measured in-situ inserting manual probes, while moisture measurement requires of lengthy laboratory based techniques. The Compoball system has been validated and demonstrated to the European Composting industry.

There is a clear need to provide composting operators with improved process control technology, especially in view of increasingly stringent and evolving regulations. Such regulations, along with market demands for high quality, stable and safe composting are clear drivers for bridging the current gaps in compost monitoring and control technology. The Compoball system has the potential to raise the quality of the EU composting process and products, minimizing the environmental impact and improving the economic returns to the waste management industry.

Project Context and Objectives:

Composting is nature's way of recycling organic waste into valuable fertiliser. It is a natural biological aerobic process in which microorganisms such as bacteria and fungi break down organic matter. Since approximately 45-55% of the waste stream is organic matter, composting can play a significant role in diverting waste from landfills thereby conserving landfill space and reducing the production of leachate and methane gas. According to the European Compost Network, at the moment around 2500 compost and waste digestion sites treat 35 million tons of organic waste across Europe which is around 1/3 to the potential of 115 million tons estimated for the year 2020 in the report by Bio Intelligence Service on behalf of the European Commission published in January 2012.

A composting process that operates at optimum performance will convert organic waste into stable compost, with reduced volume and weight that is odour and pathogen free and a useful product for improving soil characteristics. An effective composting program can produce a high quality soil amendment with a variety of end uses and the economic returns of composting can be significantly increased by improving the quality of the final product.

Composting can treat a wide range of raw materials. Organic fraction from municipal solid waste, sewage sludge, manure and agri-food industry wastes are the main groups of material treated biologically but the physical and chemical characteristics of every one of them vary extensively. Aspects like homogeneity, moisture, and organic matter composition need of an intensive change on the treatment conditions during composting to optimise product quality and to reduce nutrient losses and environmental impact. Properties like oxygen content, temperature, moisture, material disturbance, organic matter and the size and activity of microbial populations, are critical to the composting process and most of them depend on the management process.

Moisture is necessary to maintain the biological activity, but different levels have to be considered depending on the phase of the process. During the decomposition phase of composting a range between 40-60% of moisture should be kept to help in the maximum degradation, while in the maturation phase, water requirements are quite lower. Due to this microbial activity, an increase of temperature is observed as consequence. Temperature monitoring provides information about the biological activity. Additionally, this increase of temperature allows for the hygienisation of the material, actuating on the elimination of pathogen and weed seeds.

While the main biological and chemical parameters affecting the composting process are well known, the technological solutions available for monitoring and controlling the process are very limited. Essential parameters, such as temperature and moisture in the core of the material that is being composted, are currently only measured from time to time and in a number of very limited points. Moreover, temperature is usually measured manually inserting a probe, and the moisture is measured by extracting samples that need to be analysed in a laboratory and the result is obtained after 24 h. The variation of these two parameters can be very wide even in a short distance within the compost pile, and this is why it is important to be able to monitor them in as much points as possible.

There is a clear need to provide composting operators with improved process control technology, especially in view of increasingly stringent and evolving regulations (Directive 99/31/CEE, Directive 2008/98/CE, COM (2008) 811, Regulation 1069/2009/EC, Regulation 2003/2003/EC expected to be revised in 2013). Such regulations, along with market demands for high quality, stable and safe composting are clear drivers for bridging the current gaps in compost monitoring and control technology.

The COMPO-BALL system will provide the composting and the waste management industry with a novel on-line monitoring tool to control their product quality and that has the potential to improve the efficiency and economic return of the composting process. The 3-year research project is funded by the European Commission and brings together 16 partners from 9 European countries. The aim of the project is to bring affordable wireless composting-sensors to the European composting industry.

Project Results:

The COMPO-BALL system has been developed to measure the temperature and humidity during composting processes via autonomous, encapsulated wireless sensor nodes.

The system consists of

- Novel independent wireless sensor nodes that can be distributed in the composting material, novel sensors for the contact measurement of temperature and humidity inside the composting material and novel contactless battery charging system
- A wireless communication network that allows the autonomous sensor nodes to communicate with each other and to communicate and transmit their data to a pile-hub device
- A pile-hub device that collects the data from the sensor nodes and relays them to the gateway.
- A simple-to-use web interface for monitoring the data and controlling or adjusting the whole COMPO-BALL system
- A simple and clearly described procedure for the deployment of the balls at the beginning of the process and their recovery at the end of the process.

COMPO-BALL brings a complete solution not seen so far in the industry. The sensors and the communication system are integrated into one simple encapsulation. COMPO-BALL facilitates measuring in multiple points inside the composting matrix. It is the first system offering real-time measurement of temperature and humidity.

The key innovative technical characteristics of the COMPO-BALL monitoring system are

• Multiple measuring points per pile
• Total encapsulation of the wireless sensors in an inert protective material
• Contactless moisture and temperature sensors: no corrosion or blockage of sensors
• Contactless inductive charging system
• Complete wireless installation of the sensor nodes and pile-hub.
• Reliable moisture and temperature sensors with minimal calibration
• Collected data accessible by means of a web-based user Interface from anywhere, any time.

The first phase of the project focused on defining the technological needs and aspirations of the European Composting Industry. SME-AGs provided their expectations within the consortium and both the industry and research partners worked closely together to define the industrial specifications of the COMPOBALL system. It was decided to work on the development of an online system for the measurement of temperature and humidity of compost to meet the most pressing needs for improved measurement capability in the organic waste management industry.

Following the industrial needs and system specifications the next scientific and technological objectives were

• Design and development of the temperature and humidity sensors: The first validation of the sensors took place in the first year laboratory tests, while industrial validation commenced in year two.
• Studies on the protective ball material both in terms of its suitability for protecting the balls against the harsh environment and strong mechanical impact in windrowing processes, as well as ensuring that no heavy metals or other substances are released into the composting matrix.
• Many tests were performed by all the project partners in different composting facilities across EU, in order to explore the functionality of the system with the different composting machinery available.

First trials were performed with foam polyurethane which did not perform well. The encapsulating material was then changed into a rigid-polyurethane material. This second encapsulating material had important effects in the wireless communication system and several trials and tests had to be done during integration

• Building the Wireless Sensing Network

– External communication technology for the pile-hub and gateway
– The choice of the communication technology for the intra-ball network inside the composting matrix

• Development and characterisation of a contactless battery charging system for the COMPO-BALLs including a charging plate and inductive system inside the nodes.

After this first development phase of the project a second phase started in order to integrate all the system components.

• System Integration and Laboratory Testing

- Integration of components into the complete COMPO-BALL unit
- Several manufactured versions of the nodes were delivered, with changes in the integrated communication system and antenna that were affected by the encapsulating material.
- Pile hub was designed and programmed for its use as the gateway of the WSN.

During the third phase of the project the Compoball system was validated in real composting facilities.

• Validation and field trials

The COMPO-BALL system was installed in four different composting plants and further tests were performed in seven additional composting plants across Europe.

Recovery tests were performed and nodes with a new shape and density were manufactured in order to minimise the effect of the turning machines on the WSN nodes. Final upgraded user interface for the Compoball system was developed.

Given that this project delivered a pre-competitive prototype system, post project development work would be needed to industrialise the precompetitive output to a commercial system that is market exploitable. Post project development work is needed in order to make a fully commercial system for on-line compost monitoring tool. The Consortium is confident that there is potential for developing a fully commercially exploitable on-line compost monitoring tool.

Potential Impact:

The Compoball system offers a novel on-line compost quality monitoring tool to bridge the current gaps in compost monitoring and control technology.

The COMPO-BALL system brings a complete solution not seen so far in the industry. The sensors and the communication system are integrated into one simple encapsulation. COMPO-BALL facilitates measuring in multiple points inside the composting matrix and it is the first system offering real-time measurement of both temperature and humidity.

The key innovative technical characteristics of the COMPO-BALL monitoring system are

• Multiple measuring points per pile
• Total encapsulation of the wireless sensors in an inert protective material
• Contactless moisture and temperature sensors: no corrosion or blockage of sensors
• Contactless inductive charging system
• Complete wireless installation of the sensor nodes and pile-hub.
• Reliable moisture and temperature sensors with minimal calibration
• Collected data accessible by means of a web-based user Interface from anywhere, any time.

There is a clear need to provide composting operators with improved process control technology, especially in view of increasingly stringent and evolving regulations (Directive 99/31/CEE, Directive 2008/98/CE, COM (2008) 811, Regulation 1069/2009/EC, Regulation 2003/2003/EC expected to be revised in 2013). Such regulations, along with market demands for high quality, stable and safe composting are clear drivers for bridging the current gaps in compost monitoring and control technology.

The project partners are confident that the results of the project will assist in compost quality analysis and compost production. Since approximately 45-55% of the waste stream is organic matter, composting can play a significant role in diverting waste from landfills thereby conserving landfill space and reducing the production of leachate and methane gas. According to the European Compost Network, at the moment around 2500 compost and waste digestion sites treat 35 million tons of organic waste across Europe which is around 1/3 to the potential of 115 million tons estimated for the year 2020 in the report by Bio Intelligence Service on behalf of the European Commission published in January 2012.

Central to the expected impacts, are the environmental benefits of the Compoball system. Compost monitoring implies a good quality final product, with reduced environmental impact, odour and pathogen free material, and reduced volume and weight. A good quality organic fertilizer improves soil quality and reduces current chemical fertilizers consumption and other aggressive agricultural techniques.

In addition to huge environmental impacts, the economic returns of composting can be significantly increased by improving the quality of the final product. The on-line monitoring of compost quality can reduce lengthy laboratory tests without adding any extra personnel costs to the composting facilities. Central to the expected socio-economic impacts is the boosting of the competitiveness of companies operating along the waste management industry and by improving the availability and quality of European compost.

IPR and Exploitation of the results by the SMEs and SME-AGs

Validation and industry trials have been accompanied by demonstration and training activities to the European Composting Industry. All these activities have been accompanied by discussions and actions aimed at properly protecting the Intellectual Property and developing a suitable and business plan for the exploitation of results. In particular, although insufficient novelty prevented the partners from patenting the Compoball project results, the know-how that allows a competitive edge to the project partners will be protected by their continued treatment with utmost confidentiality. The Compoball results could be licensed and kept as trade secret. A strong effort has been done by the Consortium towards the registration of the SENSOBALL TM Trademark and discussion on the possible exploitation routes are currently very active during the post-project phase.

Dissemination of the results

Non-confidential information on the results and principles of the COMPOBALL technology has been successfully disseminated during the whole project duration. A second version of the public website of the project (http://www.sensoball.eu and www.compoball.eu) informs the public and any interested parties about the basics of the technology, features the press releases, news and the publishable version of the project results via an on-line training tool and a summary video. A variety of press releases were successfully circulated in newspapers, magazines and professional composting magazines and websites, raising awareness of Compoball both in industry and in the public domain. Results have been also disseminated to the scientific community via scientific publications and participation in trade shows and conferences. Industry partners have contacted standarisation agencies and made them aware of the Compoball technology. SME-AG partners have continuously spread the results of the projects to their members and many training and dissemination events have taken place. The interest and feedback generated by successful dissemination activities highlight the present demand in the composting industry for innovative technology as well as industry’s willingness to invest in such innovations.

List of Websites:
www.compoball.eu

For further information please contact:
Dr. Mirta R. Pinilla
Innovació i Recerca Industrial i Sostenible
Avda Carl Friedrich Gauss
08860 Castelldefels
Barcelona
Spain