It’s a Dirty Job, but somebody has to do it!  

Industrial filtration and waste treatment specialist, Micromac Filtration (UK), has successfully completed a major refurbishment project on a Biotower operated by Augean Treatment Ltd. It was the first time that the Biotower had been overhauled and despite the project proving to be considerably more arduous and labour intensive then first envisaged, Micromac still succeeded in bringing the project to a successful conclusion on time and within budget.

Augean Treatment is a market-leading UK based specialist waste and resource management group delivering a broad range of services to the hazardous waste sector. The group offers commercial and compliance led solutions in a complex, legislation driven market.

Standing at over seven metres high and with a 15 metre diameter, the Biotower is on site at Augean Treatment’s Avonmouth works. It was installed in 2001 to treat waste output from the on-site Effluent Plant prior to discharge to a sewer. The waste materials treated are primarily waters split from waste oil / water mixtures on site and incoming waste water contaminated with organics that cannot be put to sewers by the waste producer.

The Biotower is a large tank filled with plastic media: the effluent to be treated is pumped to the top of the tank and sprayed through four rotating distribution arms above the media. The effluent is sprayed evenly over the plastic media and trickles through it to the base of the tank, where it collects in a sump and the process is repeated. This recirculation process repeats several times. The effluent flows over a weir and is then discharged. By trickling the effluent over the plastic media, which has a high surface area, it is oxygenated so bacteria and other organisms can grow. These organisms eat the contaminants within the effluent, cleaning it to a state that can be legally disposed of to the sewer.

When the going gets tough…
Augean Treatment appointed Micromac Filtration to remove all the old media, which was very heavily contaminated and ineffective, then replace with new media. It was a strenuous task since the media had to be manually removed before the tank was cleaned and a new floor built to provide support for the fresh plastic media, which was blown in.

The project took just over a month, with Micromac teams working seven days per week from start to finish in order to complete the job. The Biotower is working again and its rate of recovery has exceeded expectations leading to increased bottom line financial efficiency for Augean Treatment.

“Originally, we were attracted to Micromac by the timescales they proposed and their reasonable costs,” explained Tim Young, Site Manager at Augean Treatment’s Avonmouth site. “However, in hindsight, what worked best for us was Micromac’s ability to run the project without too much disruption to our site and minimal input from our own personnel.”

“Based on our experience of working with the Micromac team, we would certainly work with them again on projects in the future,” Tim Young concluded.

Specialist waste treatment knowledge
The Biotower refurbishment was the first time that Micromac had worked on this application and it was able to bring knowledge and experience of working in other industry sectors with heavily contaminated materials.

“It wasn’t until we opened up the Biotower that we realised just what a challenge we had on our hands,” commented Lee Gilbert, Project Manager at Micromac Filtration. “Not just the degree of excess biomass that we found, but also the tight timescales that we had undertaken. Despite this, we battled through and delivered a solution which meets our professional standards, on time, in budget and without cutting any corners.”