Abstract:
An above grate based inlet filter system for erosion and sediment control comprises a natural fiber filter mat configured to extend beyond the perimeter of the grate and a securing mechanism, such as magnets, configured to securing the filter mat around the perimeter of the grate. The system may include a filter berm secured in vicinity to the mat, and a rectangular array of magnets coupling the filter mat to the grate. The natural fiber filter mat may effectively be a coir fiber filter mat extending beyond the perimeter of the grate, wherein the coir fiber filter mat is formed of vertically aligned coir fibers. The optional filter berm may be effectively formed as triangular in cross section and formed of 100% reticulated polyether foam and formed to be at least 3″ in height.
Abstract:
A system for rapidly dewatering sludge in large quantities makes use of a filter plate that is capable of supporting heavy mechanized removal equipment without damage to the filter plate. The filter plate is monolithic and includes granular filter material that is rigidified and bonded together. In the disclosed process, sludge is pretreated with a polymer coagulant that breaks up solids and flocculates the sludge particles. The flocculated sludge is then spread on a bed of filter plates. As the bed is being filled, the large coagulated sludge particles settle and water is drawn off by gravity. A vacuum is then applied to the bed and the sludge is rapidly dewatered. Upon completion of dewatering, front end loading equipment may be used to remove the dried sludge cake from the bed.
Abstract:
A method of spreading a pulp for the purpose of drying it naturally, the pulp having a solid fraction which has a d.sub.80 of less than 100 microns. This method comprises the following steps:(a) adjusting the level of solids of the pulp to between 2 and 25%;(b) adding a flocculating agent to the pulp and mixing it with same, the amount of said flocculating agent being between two thirds and 98% of the optimum required for the flocculation of said pulp; and(c) spreading the mixture of pulp and flocculating agent, in the open air, in a bed the sides of which are permeable, and the bottom of which has a slope of less than 5 meters per 1000 meters, said spreading taking place 1 to 20 minutes after the adding and mixing of the flocculating agent.
Abstract:
Modules for use in forming rigid filter beds by laying a plurality of the modules side-by-side upon a flat base are in the form of porous, planar elements having a continuous, polygonal upper surface, a continuous lower surface approximately coterminous to the upper surface, and sides normal to said surfaces of substantially equal depth much shorter than their length, such elements comprising laminated layers, each layer being formed of particulate material of substantially uniform size rigidly fixed together in a matrix of cured binder, the particles of the layers being substantially different in size than the particles of the adjacent layers, the top surface being flat and the bottom surface being channelled. In preferred forms, the modules' surfaces are square, there are only a top layer and a bottom layer, the top layer is much thinner than the bottom layer and the particles in the top layer are appreciably smaller than the bottom layer particles.Methods of forming the modules and of using them to form filter beds are also disclosed.
Abstract:
An eductor truck having a frame with a settling tank pivotally mounted thereon. The settling tank having an eductor unit and a valve for the eductor mounted on the tank. The valve has an arm which can be used manually or by use of a hydraulic unit to operate the valve. A storage unit is mounted on the frame adjacent the settling tank. Pivoting means and door latching means are also provided.
Abstract:
A waste water filtration and sludge removal system for filtering and removing sludge materials suspended in water resulting from steel pickling and cleaning operations and the like. The system includes a trough-like filtering tank having weep holes along the lower edge draining into an inclined channel for capturing filtered water for reuse, and also includes a multiple layer filter bed containing an upper layer of fine jagged surfaced particles for capturing filtered sludge. The sludge layer deposited on the surface of the upper filter layer is periodically moved by means of an adjustable screed blade toward an elevated discharge station for removal from the tank without significantly disturbing the filter bed. The screed blade may be automatically raised out of contact with the sludge layer when operated in the reverse direction.
Abstract:
A portable liquid-solid separator tank having a bed with a drain, surrounding sides and a dividing wall. A grate overlays the interior of the vessel, bed, and sides, and forms the dividing wall. A filter overlays the grate, extending up the sides and covering the top and the dividing wall. The separator, which may be vacuum loadable, is filled with a sludge which is then separated from the liquid it contains by gravity and hydrostatic pressure which force the liquid through the filter. Liquid is drained out of the bottom of the vessel and the solids are transported within the vessel. The solids are removed through a gate that may be provided in the tank, or by using a hydraulic lift system in much the same manner as a garbage truck empties a municipal dumpster. The filter is removed with the solids and usually discarded.
Abstract:
A selectively removable gravitational and vacuum sludge filtration apparatus and method that provides for retrofit into a container and separation of the sludge solids from the sludge liquids therein. A pair of spaced vertically oriented filter assemblies each define a filtrate cavity therein and are connected by separator plates. The filter assemblies permit the flow of sludge liquids into the filtrate cavity, but not sludge solids. A separator divides each filtrate cavity into two cavity sections, a first filtrate cavity and a second filtrate cavity. Filtrate drains into first and second filtrate cavities by either vacuum or gravitational drainage, depending on the level of sludge within the container. Vacuum drainage occur in first or second filtrate cavity if either cavity is situated below the level of the sludge within the container. A first and second filtrate evacuation means provide for the evacuation of filtrate from the first and second filtrate cavities by the use of a vacuum pump. A set of fasteners hold the filter assemblies in the container and bias the filter assemblies against the container bottom. The fasteners may be released to provide for removal of the sludge filtration system from the container. Functionally applying this sludge filtration system provides a method of retrofitting a container with a sludge filtration system and removing filtrate from a sludge in the container.
Abstract:
The present invention relates to a straining device in association with the displacement of liquid through a pulp bed preferably in connection with the withdrawal of cooking liquid in a continuous digester (1) for producing chemical pulp, which straining device (2) is preferably rectangular and comprises a number of strainer-bars (3), arranged in parallel, which have been fixed to at least two rod elements (4, 5), which are placed transversely in relation to the lengthwise extension of the bar-strainers, the said rod elements (4, 5) being made of metal, preferably stainless steel, and having a strength value RP 0.2 at 100.degree. C. which exceeds 200 MPA, preferably 300 MPA, and more preferably 350 MPA, and the width of the said rod element (4) being less than 800 mm, preferably 650 mm, and more preferably 550 mm, so that the straining device becomes self-supporting.