Foam in Anaerobic Digestion

The Anaerobic Digestion (AD) and Biogas sector is currently experiencing a massive growth surge in the UK and around the world. Using what had previously been categorised as biowaste to create a self-sustaining power source with the option of selling any excess back to the national grid is becoming increasingly popular. In 2017, the Anaerobic Digestion & Bioresources Association (ADBA) found that AD plants across the UK now have enough capacity to power over a million homes, with the potential to reduce greenhouse emissions by 4% and employ up to 35,000 people.

The use of rich feedstocks to improve output generates high levels of foam during the biological reaction that converts waste to biogas. This is a significant issue for operators. It has been reported that excess foaming generated in the anaerobic digestion process can reduce gas production by up to 40%. Not only that, but excess foam can damage gas compressors, block safety valves, and even rupture entire digesters, leading to months of downtime and repairs that can cost tens of thousands. As a consequence of this risk, rising insurance costs are also a major concern for the industry. Besides the financial implications, there is also the issue of serious pollution, the damage to reputation and the potential revoking of permits as a result of a serious incident.

The challenge, therefore, is to maintain foam at the optimum production level with correctly-applied chemicals, liquids, or by other control methods - maximising the digestion process whilst reducing any risk. Previous attempts at utilising conventional level monitoring equipment to achieve this have resulted in failure; however, the application of specialised technology has proven highly successful.

Hycontrol’s foam control technology offers a practical solution to all of the above AD & biogas issues, reducing both risk and costs. Foam can be measured and controlled using the new SureSenseāŗ system to administer the preferred control method (for example, by reactively dosing the correct amount of anti-foam chemicals). This keeps digesters operating at optimum level, preventing damage to both equipment and vessels and eliminating the risk of pollution. Additionally, it can improve efficiency (and cost-effectiveness) if using anti-foam, as well as improving insurance ratings by demonstrating effective control. Please click here to read our datasheet for more information, and contact Hycontrol to arrange a site survey.

Back to news list