The NOMAD Trailer (s)
Currently, there are no mobile digestate processing solutions on the market, despite there being high demand for cost-effective technology for small plants. The NOMAD prototype was designed for small-scale applications with a processing capacity of 5 tonnes. It can move from one site to the next to process digestate.
At the beginning of the project, one single trailer was planned that included all processes of the NOMAD concept. However, during the initial planning in 2019, it quickly became clear that the logistics were more complex than expected in order to get the material into the right particle size and to send it from process to process. Therefore, the plan had to be adapted and the concept divided into two trailers. Trailer 1: Preprocessing (Pasteurization, Separation of liquid & solid) and trailer 2: Lab on wheels (Nutrient recovery and antibiotic removal).
The production of now two trailers posed challenges to the team (and especially to the partners responsible for the construction, LEAP micro AD). The construction of both trailers at the same time was quickly considered unrealistic and trailer 2 was prioritized as it was vital for the second part of the NOMAD project. At biogas plants with appropriate conditions and with an additional filtering unit in front of it, this trailer could already travel to the Democase countries and test the NR (nutrient recovery) and AR (antibiotic removal) processes from different digestates. The resulting biofertilizer could then be tested in field trials with lettuce.
After completion of Trailer 2, work on Trailer 1 was then carried out at full speed. Trailer 1 is important for the NOMAD concept to be able to work autonomously and independently of the conditions of the biogas plants.
On the Road
The journey begins
In Mid February 2022, Trailer 2’s long-awaited journey began as it left its build site in Chelworth, Malmesbury, UK and its wheels rolled onto tarmac for the first time. Its destination was the port of Southhampton, where it was to travel by cargo ship to Athens, Greece.
Of course, such a trailer is not easy and quickly shipped and the stay in the port with all the entry / exit regulations, customs and so on took a bit (especially since BREXIT).
At the beginning of March, Trailer 2 finally left the port. The crossing to Greece took a month and in early April Trailer 2 reached its first destination, Athens. Also in the port of Greece, the port authorities had to check that everything was correct and after a few days, Trailer 2 was finally allowed to drive to CERTH in Thessaloniki.
The CERTH team happily welcomed Trailer 2 and spent the next 3 months preparing for the real trials at the biogas plants. They had to check that nothing had broken during the long journey, machines had to be calibrated and tested, materials had to be stowed on board and the scientists who would accompany the trailer on its journey familiarized themselves with everything down to the last detail.
Let's get dirty!
In mid-July, the time had come and Trailer 2 was ready for its first test run with real digestate. Location: Voreioelladiki Biogas Plant (near Thessaloniki). The biogas plant is operated with a mixture of animal waste, agricultural waste and dairy products. The digestate for the NOMAD trailer was taken from the lagoon. Testing was carried out at this biogas plant until mid-October.
Voreioelladiki Biogas Plant (near Thessaloniki)
From 20th to 23rd October the Agrotica fair took place in Thessaloniki, so we took advantage of the moment and drove by there before visiting the next biogas plant and presented our Trailer 2 to the international visitors who were interested in Agricultural Machinery, equipment and Supplies.
Agrotica - 29th International Fair For Agricultural Machinery, Equipment & Supplies
At the end of November, Trailer 2 went on its second sea voyage, from Athens to Salerno, Italy. Once there, and having survived all the bureaucracy, the journey continued overland to the next biogas plant ‘Agri Power Plus’ near Latina. Here the biogas plant is operated with agricultural residue and we were able to get our digestate again from a screw press.
AgriPower Plus Biogas Plant (near Latina)
At the beginning of January 2023, Trailer 2 then continued on to Malta, another voyage by ship from Salerno to Valetta and a short drive on the island. The destination on Malta was the Wasterwater Treatment Plant Ta’Barkat. Here we were able to obtain the digestate from a centrifuge.
Ta'Barkat Wastewater Treatment Plant (Malta)
Once more to Greece
At the beginning of April 2023, Trailer 2 returned to Greece for final tests and post-processing at CERTH. With NOMAD project, ending at the end of June, the journey of Trailer 2 ends here for the time being. Four biogas plants in three countries, proof of this are the three magnets on the sample refrigerator on board. The fate of Trailer 2 is not yet clear. Its partner trailer is currently still being completed in Chelworth, UK. One plan is for the two to meet in the UK in the near future.