Support Grows For More Mixing Fine Tuning To Improve AD Plant Efficiency

Citing Feedstock, Mixing and Monitoring as three key areas in which to gain benefits from being more proactive, Privilege Finance’s Technical Director Phil Hobbs commented on how poor mixing of digestate will have a detrimental impact on feedstock performance.

Landia’s Key Account Manager Paul Davies said: “Fine-tuning of a farm-based AD plant can bring about significant savings on maintenance and energy, as well as greatly improve gas yields. So, if your plant isn’t realising its full potential, a retrofit of the mixing system – especially one that puts all moving parts on the outside of the tank, can definitely improve efficiency”.

Davies also states that many mixing systems may have 7.5kW motors, but that in most cases, these are running flat out, using 180 kW hours per day.

For what he describes as ‘complete mixing of the whole digester’, Davies suggests farm-based AD operators consider 18.5 kW motors that only have to run for 10-15 minutes per hour, using just 110 kW hours per day.

Landia’s retrofit mixer installation at Eco Sustainable Solutions’ AD plant in Dorset increased gas yields by a massive 12.5% and also reduced energy usage by 50%. This feat was recognised by ADBA, with a Highly Commended honour at its annual awards.

Davies added: “As rightly stated by Privilege Finance, the potential to improve efficiency of your plant is very much attainable. Even if your AD operation seems to be running along adequately, you can fine tune it with a better mixing system to reduce energy and maintenance costs. Together with improved monitoring and better quality feedstock, you can significantly enhance your gas yields”.