Skip to main content

Recycling technology to introduce rubber from End-of-Life Tyres into production lines as virgin rubbers substitute

Periodic Reporting for period 1 - VALUE-RUBBER (Recycling technology to introduce rubber from End-of-Life Tyres into production lines as virgin rubbers substitute)

Reporting period: 2019-09-01 to 2020-08-31

Value-Rubber is a research project aimed at the recycling and reuse of tires from vehicles at the end of their useful life. End-of-Life-Tyres (ELTs) recycling is a global issue, also in Europe. Some efforts have been made to mitigate this problem but none so far have proven to be completely effective. What we do with ELTs is both a challenge and an opportunity. One of the main European challenge is to turning waste into a resource. In this sense, in line with the principles of circular economy, ELTs should now be considered as a very valuable resource. Rubber is a key raw material for Europe since is either a petroleum based (Synthetic rubber) or imported (Natural rubber) source. The Value-Rubber business opportunity relies on all of these arguments since we have developed a game-changing ELTs recycling technology (DevulCore) that will offer a stable price and good quality raw rubber source for Rubber Goods Manufacturers which could replace current virgin rubbers without diminished quality. In addition, ELTs recyclers will increase recycled rubbers added value and will reduce its stock by opening to new markets.
Value-rubber technical solution: DevulCore is a complete devulcanization technology, it permits both the strict control and the tuning of the devulcanization process parameters, being able of selectively break C-S bonds, without breaking main chain C-C bonds. Value-Rubber technology enables the whole selective bonds breakage; hence it will fully recover properties and structure of those virgin rubbers used for tyre manufacturing. DevulCore offers devulcanized rubbers suitable to all industrial viscosity ranges, improving dramatically the procesability.
VALUE-RUBBER has the following main aim:
1- To carry out technical activities in order to transfer previous batch process validated at functional level into an operational modular prototype of 30 kg/h aiming at demonstrate DevulCore technology and Value-Rubber Family in operational environment as well as to assure a fast industrial scale-up.
2- To promote technology and products involving stakeholders and end users as well as making it ready our commercial plan in order to assure a successful market entry in TIER-1 markets, and further TIER-2
T 1.1 Definition of project technical requirements
Inputs from all partners have been collected in a first Kick-off Meeting with a particular attention towards the industrial and end-user point of view. The feeding speed range, temperatures range, operation parameters and the critical control points along all the process have been established, aiming a goal of 30kg/h production rate for the prototype.
Material specifications have been defined. The payload considered to be processed is crumb rubber with a particle size within [0.6 2.0] mm as the most popular granulate in the ELTs recycling industry. The payload must be free of metal impurities.
Operational parameters range have been also defined.
Respect to the power consumption estimation for the microwave module, it has been estimated a maximum power consumption of 4,8 kW.
Despite the power rate for the extruder is 15 kW, a real consumption lower than this value is expected because rubber is already at high temperature from the microwave.
The software functions have also been defined.
Some critical control points have been identified in order to prevent malfunctions or accident in the control of the process, for example, some temperature controls, arcind risk prevention against magnetron or air pollution control.
Respect to the extruder system, it has been defined a barrel configuration with 6 zone types.
The temperature range specification for each extruder zone has been defined.
Interconnection between microwave module and extruder has to be studied carefully because microwave process is a batch process and extruder process is a continuous process.
T 1.2 extruder engineering
6 extruder zones have been defined with a length-diameter ratio of 40. Every zone has its own kind of screw for a desidered function.
Methods to calculate values as screw speed, residence time, fill factor and temperature ranges has also been proposed.
This extruder configuration has been tested in a lab extruder scale. The ground rubber have been processed in the lab extruder resulting in outstanding values of devulcanization, 13% of soluble fraction and 98% of devulcanization.
T 1.3 Engineering of the prototype microwave module
The first study corresponds to the power consumption for the microwave module. It have been estimated between 2 and 5 kW.
The software functions haave been identified and should be developed
Finally critical points that must be taking into account have also identified.
T 1.4 Auxiliary elements design. Software implementation
Different auxiliary elements for the correct operation of the whole system have been designed.
-Mechanisms for the payload uploading/downloading into/from the system.
-Payload transferring between modules at the extruder/MW interface
-Gas filters and gas monitors
-Software implementation, including a friendly operating system.
T 1.5 Efficiency and cleaning systems. Designs verification.
The cleaning mechanism, the system for energy recuperation/optimization and the cooling system have been designed.
The system for energy recuperation/optimization and cooling system have been designed.
System integration and verification
Both systems, microwave and extruder have been tested satisfactorily but separately.
T 2.1 Prototype MW construction. Functional control
The microwave prototype is almost finished. Due to COVID19 the construction have been delayed.
T 2.2 Prototype extruder installation. Functional control
Synthelast has adquire the extruder according the specifications fixed at T 1.2. The extruder is still under construction. Due to COVID19 the construction have been delayed.
With respects to dissemination actions, first of all a communication and dissemination plan has been designed.

T 5.1 Different communication actions have been carried out like the ValueRubber website, and workshops, meetings and technical information sessions abbou ValueRubber project. Most of them in a remote way due to COVID19 restrictions.
Due to the great interest aroused by the project, some dissemination actions have been carried out like remote presentations of the project have been performed to different stakeholders in order to announce the first results and project progress.
Some press communications have been sent to the national newspapers

With respect to exploitation issues, it is a bit early to conclusions but some actions have been studied like identify eligible results and analyse exploitation potentia or support activities for IPR protection.
Currently, the extruder and microwave prototypes are almost finished. The next step is to validate the technology, fully functional at laboratory level, with these prototypes.
During the progress of the project many companies and associations related to tyre have contacted with CETEC, the coordinator of ValueRubber manifesting great interest for the project developing. This interest only can be translated in a great impact at the end of the project. That is, a technology to revert the vulcanization and introduce the tyre rubber residue in the production line again.
Microwave construction detail 2
Contact with SIGNUS: spanish tire collection management system
hydralic system detail of the extruder
NEUMATIMUR and FREMM visit CETEC to get information about ValueRubber