Patent Application
20070272271
As shown in
This structural combination may be supported on ground on a pair of C-channel sectioned skids 14 and 15 extending longitudinally beneath bottom panel 11 in a spaced alignment relative the bottom surface, with the channel spacing fixed by the lower edge projection 41L of panel assembly 41 at one end to a direct contact with the bottom panel 11 at the forward edge. In this manner a forwardly biased downward inclination of the bottom panel 11 extending between the lateral walls 12 and 13 is provided to direct the fluid flows towards wall 21. A set of outer rollers 46 and 47 at the lower corners of panel 41 then provides rolling convenience over ground while another set of support rollers 26 and 27 fitted adjacent the skid channels 14 and 15 at the forward end are useful in loading and unloading the structure onto tracks in a carrier vehicle CV. Once thus deployed either gate 42 is opened to allow the dispensing part DP of the washed concrete machinery CM to extend over the rear basin 40 for collecting the wash products therein that are emitted through the dispensing part DP when the machinery is washed.
Those skilled in the art will appreciate that the concrete setting process using portland cement entails a hydration reaction of the oxides of calcium, silicon and aluminum. As the hydration solids are formed the heat of their reaction, over time, drives off the excess local water that is not chemically bound as steam. This process, however, loses efficacy once an overabundant amount of water is introduced, as in the course of a wash, since the excess water flow rinses off the cement powder off the aggregate, diluting it to a point where the reaction is no longer sustainable. A thorough washing, therefore, invariably results in wholly loose aggregate along with large quantities water carrying the highly diluted cement which when allowed to evaporate to higher concentrations within the aggregate may start binding it to itself and to the walls of the container. While the bonds that result in the course of evaporation are minimally effective their result is, nonetheless, bothersome as any prolonged retention of even the highly diluted cement reagents within the residue aggregate following washing will promote hydration. For this reason, and those imposed by statute focused on limiting inadvertent spillage, a flexible membrane 60 may be positioned in basin 40 to be recovered once the residue is disposed.
If needed, membrane 60 is laid in basin 40 leaving exposed the conveyance paths for a controlled draining of wash fluid that also carries away with it the diluted cement powders forming the paste for collection in enclosure 20, while at the same time separating and leaving behind the sand and washed aggregate in basin 40. To effect this the separation wall 21 includes a pair of vertically aligned tubular housings 25l and 25r each straddling the plane of the wall proximate the corresponding right or left side wall 12 or 13 within conforming wall surface gaps. Both the housings 25l and 25r are provided with a corresponding narrow vertical slot 28l and 28r formed in that portion of their walls that extends into the basin 40 while substantially larger openings 29l and 29r are formed in the opposing housing surfaces that extend into enclosure 20, thereby forming a liquid communication path thereacross. A set of conforming cylindrical filter assemblies 24 are then each receivable in the corresponding housings 25l and 25r to control and limit any transfer of the larger sized particulates of the aggregate. After insertion filters 24 may be periodically turned relative the slots to present a fresh surface to the flow. Preferably, the vertical slots 28l and 28r are each of a narrow transverse width dimension that is smaller than the dimension of the bulk of the aggregate. Consequently, the aggregate and sand will accumulates at each of the slots to form a filtering bed FB that further limits any aggregate transfer into enclosure 20.
Those skilled in the art will further appreciate that any concrete equipment washing is best effected by substantial and robust water streams. Simply, since the concrete transit and pumping equipment, in itself, provides a fairly integral enclosure having few exit openings robust washing stream WS is needed to reach all the interior surfaces thereof. As result the wash product flows that emerge from the washed mechanism are themselves quite agitated, thus providing the energy in basin 40 to further disturb the aggregate beds that have collected therein. In the course of this further agitation any of the cement paste that may remain in the bed is further dispersed and diluted, thereby limiting any potential of setting of the wash products therein. The resulting aggregate bed that accumulates at each entry slot will therefore remain in its loose form for convenient disposal out of the basin once it is full. The same deposit of the sand and aggregate filter bed FB at each slot 25l and 25r also serves a decanting purpose since the higher strata of the agitated basin content will inherently contain the lower density, or more diluted, cement paste flows. Accordingly, the inventive structural arrangement synergistically obtains benefit from the washing process itself to separate the diluted concrete paste from the aggregate, thereby simplifying the removal and disposal of the inert and massive part of the wash product while the caustic hydroxide parts of the hydration reaction are separately collected for neutralization and disposal.
For these reasons the enclosure 20 is further provided with a pump-out port 121 which may be periodically connected to a powered pump 122 that transfers its caustic contents into drums 123-1 through 123-n to be thereafter neutralized and disposed. By particular reference to
In this manner the problematic components of the concrete process, i.e., the highly caustic hydroxides that are entailed in the hydration processes of concrete, are separated from the wash product stream right as it is being generated, diluting and removing at the same time the binder from the inert filler aggregate. Convenient handling of the compromised and fractured aggregate pad, the most massive part of the wash residue, is thus obtained while the component most harmful to the environment is isolated for neutralization and disposal in standardized drums, allowing for the handling and transport thereof by separately contracted enterprises that have the necessary expertise and facilities.
Of course, where the physical capacity limits of a single structure 10 may be insufficient for the concrete building project undertaken multiples thereof may be deployed at a single construction site with each structure sized for convenient handling and disposal movement along the same paths as those used by the concrete machinery. Thus both the job planning and the environmental aspects are comfortably conformed for the usual transport modes.
Obviously many modifications and variations of the instant invention can be effected without departing from the spirit of the teachings herein. It is therefore intended that the scope of the invention be determined solely by the claims appended hereto.
