Icopmas presentation 2016 by Prof Robert Kirby – SEMASO
‘TWIN RELATED ASPECTS OF ENGINEERED MUD SUSPENSIONS FOR THE NW EU’
Over the last 40 years a number of ‘generic’ technologies have been developed to more effectively manage fine cohesive sediment in harbours in a sustainable, less expensive and more environmentally friendly manner. A ‘generic’ method is one which, when tailored to local idiosyncrasies, is widely applicable at many self-similar harbour configurations around the world, (channels, semi-enclosed basins, impounded docks, etc.). Such methods are preferable to traditional, old fashioned, at times damaging, ‘dig and dump’ dredging. Adoption of this new generation of methods alters a formerly intractable waste rendering it instead a resource with a beneficial use.
The most sophisticated of these modern methods involves in-situ manipulation and control of the physical, chemical and micro-biological properties of the mud. Gentle fluidisation in the presence of oxygen shifts the chemical climate from anoxic to oxygenated. This permits large numbers of aerobic bacteria to be activated. We have learnt how to stabilise an environment in which these continuously secrete large volumes of EPS (slime). The bacteria themselves, together with their slime, can be induced to exhibit inter-related, but contrasted, functions. These twin functions are the topic of this presentation.