Patent ID: 6749745
Filing Date: 2004-06-15
Classification: C02F,Y02W

Abstract:
Apparatus for treating wastewater, wherein:the apparatus includes a container, having an inlet port for receiving wastewater to be treated and an outlet port; the container has left and right side-walls and a floor; the left and right side-walls of the container have respective inwards-facing surfaces, which define a hollow interior of the container, between which the wastewater is contained; the container includes a treatment-trough, which is of a long/narrow configuration; the treatment-trough is a component of the container, and is so arranged that wastewater, in passing from the inlet port to the outlet port of the container, passes along and through the treatment-trough; portions of the left and right side-walls of the container lie in the treatment-trough, and comprise left and right trough-side-walls; the trough-side-walls confine the water being treated in the treatment-trough, and the apparatus is so configured that water, having once entered the treatment-trough, is constrained, by the trough-side-walls, to pass lengthwise along the treatment-trough, and to remain between the trough-side-walls, to the outlet port; a portion of the floor of the container lies in the treatment-trough, and comprises the trough-floor; in a cross-section taken longitudinally along the treatment-trough, being a cross-section taken at the full depth of the trough-floor, a longitudinal-trough-floor-line is the longitudinal line that most closely follows the trough-floor, in that cross-section; an inlet-point and an outlet-point are points that lie within the container, and are the points on the longitudinal-trough-floor-line, or on extensions of the longitudinal-trough-floor-line, which are closest, respectively, to the inlet port and the outlet port of the container; the length of the longitudinal-trough-floor-line between the inlet-point and the outlet-point is termed the container-length; at each point along the container, the container has a respective container-width, being the width between the container-side-walls at that point; at least some of the points along the length of the container comprise also points-T of the treatment-trough, being those points in respect of which the container-width at the point is less than Â¼ of the container-length; the treatment-trough comprises the aggregate of all the points-T; the apparatus includes a body of treatment material, which:â€”(a) is porous and permeable to the passage of water therethrough, and is capable of supporting vigorous microbe colonies; (b) resides in the treatment-trough, and makes tight contact with the trough-floor, and makes tight contact with at least a bottom portion of the trough-side-walls, in such manner as to ensure that water, in passing through the treatment-trough, cannot by-pass the treatment material; wastewater being treated in the apparatus moves along respective paths, in passing from inlet to outlet, through the body of treatment-material; in respect of each of the respective paths, the water traverses through, and in contact with, the treatment-material, for respective treatment-lengths, being the longitudinally-projected total length of the contact of the water with the treatment-material; the shortest one of the treatment-lengths is at least two meters in length, whereby a drop of water, in passing from inlet port to outlet port of the container, traverses a longitudinal distance, in contact with the body of treatment-material, of at least two meters; the wastewater is water contaminated with carbonaceous BOD, and the arrangement of the apparatus is such: that the body of treatment material does not completely fill the treatment-trough, but an air-passage exists, running above the body of treatment material in the trough, and so arranged that water residing in the pores of the treatment material is exposed to air in the air-passage; that the air-passage is sufficiently open to the atmosphere as to enable substantial aerobic microbiological breakdown reactions of the BOD in the water residing in the pores of the treatment material.