Kiverco unveils its backbone in waste composting

Kiverco and EnVar, two waste and recycling experts in their respective fields, have joined forces to help to protect the environment and create resources for future generations as a new Kiverco waste screening plant is installed at EnVar’s organic waste treatment site in Cambridgeshire.

EnVar and Kiverco
EnVar is the UK's largest waste in-vessel and windrow composting facility and currently recycles: food waste and green waste, co-mingled food and green waste and specific organic waste. With 30 years’ experience in composting, EnVar now works with a number of Local Authorities throughout the UK.

Kiverco consults, designs, engineers and builds uncompromisingly robust recycling plants for the waste processing industry, utilising the latest technology to consistently provide reliable output and recovery, in line with the latest industry developments.

The Woodhurst Site
Regularly operating to full capacity and with 16 full time workers, the EnVar site is incredibly busy. Recycling peak times change and weather impacts on the process too. For example, in the summer, as temperatures increase and the nation gets greener fingers, huge levels of garden waste can be expected. During such times, staff can expect to see 35 loads a day of mixed food and garden waste, each weighing 26 tonnes.

As the waste arrives it is immediately mixed, shredded and blended, then water is added before the material is transported into a tunnel as part of the “in vessel” composting system. During this process, the environment is managed carefully so that the material reaches a temperature of 60° for 48 hours as this eliminates undesirable pathogenic bacteria such as Salmonella, E.coli single protein production and even weed seeds. The tunnels at EnVar can take up to 450 tonnes of waste in one vessel. Once this process is complete, the waste is transferred to a maturation pad outside and exposed to the elements. After 8-12 weeks of turning to achieve aeration and close monitoring, the waste is ready to be transferred to the recycling plant for final processing to produce a top quality soil improver and other similar products.

The Challenge
In order to improve throughput and product quality, EnVar called in Kiverco to review operations. In July 2014, the local Kiverco Area Sales Manager, JP Devlin, met with Neil Pickard, then Executive Director of Envar, to discuss the company’s requirements for a new recycling plant. The Kiverco service always starts with a detailed review of the client’s present activities and crucially, further consideration of the outcomes the client is looking for. This approach is critically important and enables Kiverco to gain the best possible understanding of the customers present a future needs. During this process, Kiverco carries out tests on the input material, so as to clearly understand its composition and uses the results gained when making their final proposals.

After detailed discussions, it became apparent that the EnVar site required one purpose designed static plant as opposed to the five separate systems that were currently being used. The workers had experienced problems as the different plants required individual maintenance and management. It was also vital for EnVar that the new plant could easily cope with the increasing daily volumes of waste being handled at the site and be flexible in terms of the different fractions that can be sifted.

The Solution
After listening carefully to the requirements outlined by Envar, Kiverco designed and installed a custom built composting plant, able to separate household organics and recover recyclables with maximum efficiency. This plant was unveiled in September 2015.

Commenting on the design of the plant, JP Devlin at Kiverco said “When engineering this plant, we were not afraid to do something different to ensure the client had the best solution for their specific needs. This involved us working closely with third parties throughout the process to ensure every element of the plant was perfect for EnVar.”

The plant has eight different systems within it that ensure maximum uptime and therefore maximum output. These include:

1. Dosing feeder- giving a consistent and metered flow of material into the plant 
2. Waste screen- separating material with measurements of less then 150mm
3. Picking station- manually removing any contaminants such as plastic films from the material, leaving a clean wood fraction to be re-used as a bulking agent for the composting process 
4. Combi station- screening out products of 0-10mm and stockpiling it, and splitting material of 10-30mm & 30-150mm using a vibrator screen 
5. Density separation- conveying the material left ( 10-30mm & 30-150mm) and removing light contaminants, such as papers and plastics 
6. In-line magnets – passing the material beneath in-line magnets for the removal of ferrous metals 
7. De-stoner – removing the stone from the two fractions 
8. Quality control- manually removing any remaining contamination from the material to leave clean, organic product either for re-use as a bulking agent or biomass outlets

The plant also boasts an electrical control room, generator, and a large capacity fuel tank.

The Results
Ultimately, the Kiverco plant enables the EnVar site to produce a quality, PAS 100 & CQP certified soil conditioner for the agriculture and amateur horticultural markets. Now operating fully, the plant is contributing towards the site processing 105,000 tonnes of co-mingled food and green waste per year.

Richard Adcock, EnVar Site Manager said: “Kiverco has provided a robust solution with the lengthy lifespan we need. We have locally recruited 5 additional members of staff to assist with the plant, demonstrating how the system will increase our capacity levels. Working with Kiverco, EnVar can confidently look forward to a successful future.”

John Lines, Sales and Marketing Director of Kiverco said: “It is always a pleasure to work with our customers and see in action the differences that our plant can make to the waste management process. As a company we strive to minimise the amount of waste that is sent to landfill and we hope to help EnVar continue to reach its full potential in the composting industry.”