Membrane filters can be used for final filtration or prefiltration, whereas a depth filter is generally used in clarifying applications where quantitative retention is not required or as a prefilter to prolong the life of a downstream membrane. Membrane and depth filters offer certain advantages and limitations.
Concrete Hard-standing-When using concrete as a surface to support your new shed, you must ensure that it is level, flat and that it is dry in time for your shed delivery and installation. Here are the basic steps: 1  Using pegs and string, mark out the base area (allow 5 cm extra).
The stone to be used for constructing the storage shed foundations should be what is known as 'well graded material'. This means that there is a good mix of stone sizes from about 40mm diameter down to very fine dust. The best material for this in the UK is sold as Department of Transport Type 1.