Out of the study of the London sewage and its behavior in the Thames came the conviction that purification could be carried out by natural processes, without the intervention of chemicals, and thus was evolved the biological treatment in contact beds, which system, destined to revolutionize sanitary engineering, was developed at the Northern Outfall Works at Barking Creek, and later at Sutton, Surrey, for the Sutton Urban District Council, where the first “primary” or “coarse contact” beds were laid down. As is generally known, the fundamental idea of the process is the destruction of foul matter by the action of living organisms in the presence of air, the process has been most successful, difficulties only being met with when an attempt has been made to drive the beds too hard, the spaces between the coke and clinker thereby becoming filled up. To overcome this drawback, William Joseph Dibdin set to work to devise beds which would clear themselves from the accumulated residue. This he found in the very ingenious plate beds, the plates consisting of superimposed layers of slate. Such beds, for the treatment of crude sewage, are now at work at some thirty installations, among others Devizes and High Wycombe, and prove that the objects aimed at have been attained.
- The Engineering News 1908/03/13