REgional Development and Integration of unused biomass wastes as REsources for Circular products and economic Transformation
September 2016 to September 2019
The REDIRECT project offers an opportunity to host a pan-European project where Cwm Harry is a key partner, responsible for the building and operating of a farm scale pilot plant in Wales. The preferred location for this plant is in Ffarm Moelyci, with access and setting among like minded businesses. Redirect’s purpose is to establish a farm based business model that better manages land, adds value to marginal biomass such as bracken and soft rush and generates renewable fuels at a local or rural level. If the pilot plant is a success then the plan is to share the technology across Wales. REDIRECT is funded from the European Union and incoporates 5 countries; Germany, France, Belgium, Ireland and the UK. REDIRECT builds upon the successful INTERREG IVB program COMBINE.
Each year, approx. 34 MT of residual biomass occur in urban and rural areas of North-West Europe (NWE). On the other hand, there is an increasing demand in carbon feed-stock, not only for fuel purposes but also for products, for instance in the waste water sector for activated carbon that is currently imported from African or Asian countries.
RE-DIRECT aims to set up decentralised conversion units to convert residual biomass into alternative carbon products. We will also focus on activated carbon to be used for clearing regional waste water and contaminated sites.
The project aims to create a network for alternative carbon products and promote the collection, production and value chain management of alternative coal and carbon products as a starting point to circular economy. With this it will benefit to global climate, but will also contribute to foster regional economy and deliver smart solutions to remidate contaminated sites and eliminate hazardous micro-pollutants.
The farm based process will continue with the IFBB set up, as was demonstrated in COMBINE. IFBB stands for integrated generation of solid fuel and biogas from biomass and was developed at the University of Kassel in the early 2000s. It was tested on laboratory scale up to the year 2008 and successfully up-scaled (to 1:20) between 2009 and 2012 in the forerunner project PROGRASS.
On farm the end products will be similar however there are additional avenues being explored as high value: biochar and activated charcoal:
- Biochar can be used as a soil improver and has the added benefit of sequestering carbon into the soil.
- Activated charcoal has purification properties and can be used to filter pollutants out of water or gas, for example in wastewater purification or power stations’ exhaust gases.
- The process starts with cuttings of biomass material or Marginal Virgin Biomass. Ideally we take anything with low nutritional value (e.g. grass, gorse, bracken, soft rush, balsam etc.) This is collected and stored as conventional silage bales. Stored as silage, this allows the process to operate at any time of the year and only requires farmers to use the same equipment as they would do during hay collection.
- The plant will operate at 1000T/annum. Silage can be stored on the farms of origin until needed, eliminating the need for large scale storage onsite.
- When ready to be processed, the silage is removed from the bale and broken up with the silage passing through a stage we call Mash. The mash tank soaks the silage in warm water (approximately 30-40oC) which is designed to allow soluble nutrients to be taken up in the water leaving principally carbon in the solid fraction, which are undesirable in a solid fuel and meet EU directives on burning biomass.
- The mash then passes through a screw press (akin to those used in food processing plants or the sludge dewatering sector) which separates all the liquid fractions containing the nutrients from the solids fraction containing principally the carbon, providing a enriched liquor and a carbon dense but nutrient poor fibre.
- The liquor passes through to a small fast process anaerobic digester , a similar process used in the food industry to treat surplus liquids. The AD tank is <50 cubic meters in volume.
- The biogas generated is stored onsite in a gas bubble before being scrubbed and used to fuel a small combined heat and power (CHP) plant. The modest electricity and heat produced are used on site to drive the process. It is not anticipated that there will be any excess heat and power so no export of energy is planned.
- After the production of gas (which makes use of hydrogen and carbon molecules in the liquor) , the remaining liquid is very nutrient rich (with nitrogen, phosphorous and potassium as the principle nutrients being those most in demand by the agricultural and horticultural sectors). One final stage for the liquid fraction will be to dewater by allowing the water to evaporate off before bottling and selling it as a high value bio-fertiliser/additive or soil improver.
- All water from the process is recycled back into the mash stage.
- The solids from the process are dried using the heat from the CHP (alongside natural / solar drying). This carbon based material is very energy dense and will be briquetted (compressed into ‘logs’) and conventionally sold to end users with wood burning stoves.
The principle ‘product’ that this plant and Cwm Harry is designed to ‘produce’ is a farm scale example of a technology suited to farms across Wales and then Europe. We will demonstrate how it is able to reduce costs and add value through smart use of simple technology.
As a result of the plants operation a variety of fuels (briquette’s, natural gas) and soil improvers will be produced for local retail.