This case provides a typical example of how the combined approach of boosting organic degradation and nitrification can be used successfully to achieve effluent discharge consent levels in overloaded treatment plants. The case concerned a large caravan park and leisure facility effluent treatment plant in the south of England.
The Manager of the site explains “before we were introduced to specialists from Cleveland Biotech by our Environmental Consultant, organic and the ammonia consent was repeatedly being exceeded. We had exhausted all options available to us at that time to bring the treatment plant back into line and final preparations were in hand to construct a new treatment plant for the site with a capital cost of over £300,000. Following an assessment of our plant performance, a decision was taken to install a Cleveland Biotech Activation Unit providing organic bio-augmentation of the existing plant without any other modifications being made to the plant. Within 3 weeks the organic removal efficiency of the plant had increased dramatically and was well within its discharge consent.
This higher level of organic degradation continued throughout the remainder of the season. Later in the year, following a particularly busy weekend and heavy rainfall, the ammonia level began to rise and experts from Cleveland Biotech were again called upon. After further detailed discussions, a highly active preparation of nitrifying bacteria was added to the nitrifying zone of the plant. Within 48 hours the ammonia level had dropped from over 70 ppm to less than 5 ppm and we were again within consent. As a routine precaution we now add a maintenance dose of nitrifiers once a month to the plant to keep it in tiptop condition. We start adding bacteria to the plant 4 weeks before the season starts in order to build up the bacterial population in the plant ready for the first visitor effluent load.
This way we no longer have to worry about the cost and inconvenience of importing tanker loads of active sludge from elsewhere to start the plant up again. For an annual bacterial cost of approximately £ 7,000, Cleveland Biotech has saved our site over £ 300,000 – the capital cost of building a new treatment plant”.