Tests for on-site sanitation systems

Full-scale tests using the Solido mini treatment plant performed by simulating the use of equipment by a family. Photo: Florence Joubert

How much sludge is produced by a small-scale domestic waste water treatment plant? This is the question that Premier Tech asked about its Solido activated sludge systems. It wants to provide its clients – occupants of private homes – with meaningful and substantiated information about the best conditions for use. This focus is on the frequency of flushing that ensures optimal efficiency for this sanitation solution. There is little literature about on-site sanitation, which was introduced in France less than a decade ago. The company therefore asked the CSTB to conduct a scientific and technical study to understand the laws of sludge accumulation in this type of system, to compare that with conventional systems (tanks) and to assess the impact of sludge production on performance of small treatment plants. Full-scale tests simulating the actual use of these systems by a family were conducted in 2017 by the CSTB in its Aquasim test facility in Nantes. They made it possible to establish the fundamental principles of a sludge production formula based on the waste water load input.

Roger Lacasse
vice president of the science and technology division at Premier Tech, manufacturer of certified on-site sanitation systems

“The production of sludge by compact treatment plants is little known in the scientific world, and a structured study was necessary. We consulted the CSTB because of the competence of its experts and the quality of its facilities. The quality of the tests conducted in the Aquasim facility, followed by an analysis of the results, will enable us to design treatment plants better adapted to the reality of on-site sanitation.”