Abstract: A filtration system comprising a floor panel and a plurality of wall panels connected to each other to define a box, at least one filtering wall vertically inclined and supported inward of a corresponding wall panel such as to define a first free space therebetween, a filtering floor horizontally inclined and supported above the floor panel such as to define a second free space therebetween, the filtering floor being connected to the filtering wall to define a filter chamber, a plurality of openings defined in the filtering wall and the filtering floor sized to let a liquid pass through and retain at least one target solid within the filter chamber, an inlet in fluid communication with the filter chamber, and an outlet in fluid communication with the first and second free spaces. A method of filtering at least one target solid from a liquid is also provided.

Abstract: A method is disclosed for treating sewage in which the combustible components of the sewage are separated from the sewage and utilized as a primary fuel. Scum is collected, preferably by skimming, from screened sewage. This scum comprises oils, greases, fats, water and intermixed solid material. The collected scum is then transferred to a separation tank. The scum is maintained within the tank in a quiescent and substantially nonagitated state for at least twelve hours, during which the combustible oils, greases, fats and the like are rendered separable from the other components of the scum. The scum is then conveyed from the tank to a processing unit where the fats, oils, greases and the like are separated from the water and solid material remaining in the scum. The resulting product is a combustible product and can be used as a primary fuel.