For all your sludge and dewatering needs

Or does it mean they get your sludge, take the water out of it and then dry it? Perhaps I unwittingly converted the keyhole into a  comma between sludge and dewatering.

Is dewatering a posh word for drainage?

How many sorts of sludge are there?

Read on Google results if you have too much time on your hands:

We are the leading UK supplier and rental provider of Decanters, Belt Presses, Filter Presses and Separators.
We provide a comprehensive service to deal with all sludge and effluent related problems involving the treatment, thickening and dewatering of almost any liquid – from sewage and drinking water to minerals, chemicals, pharmaceuticals and food and drinks including the processing of sand and aggregates, fruit and hop based beverages, juices, beer, wine together with exotic food products such as avocado oil, flax, lupin seeds and soy beans.
We also process fish products; our equipment is also used in the process of purifying fish oil for omega 3, and from algae and other nutraceuticals.