Patent Application
20110197980
This invention relates generally to apparatuses and methods for reclamation of concrete, and more specifically, to a vehicle-mounted apparatus and method for collection of wet concrete residue from dispensing elements of concrete delivery vehicles.
Concrete is composed of aggregate (generally a coarse aggregate such as gravel, limestone, or granite, plus a fine aggregate such as sand), cement (commonly Portland cement) and can also include other cementitious materials such as fly ash and slag cement (with the cement and cementitious materials acting to hold the aggregate together, water, and can also include other chemical admixtures. Depending on the intended use, fiberglass, chemicals and other additives can be added. Concrete is commonly transported to a construction site in concrete mixture delivery vehicles, typically concrete transport trucks (in-transit mixers) having a large rotating mixing drum. During transportation, the concrete is in a wet, relatively flowable state. At the construction site, the wet concrete mixture is installed. One typical method to deliver the concrete from the drum is via one or more pour chutes.
After substantially all of the concrete mixture is unloaded from the delivery transport truck, a considerable amount of wet concrete continues to adhere to the pour chutes. In the past, this remaining wet concrete mixture was merely hosed off onto the ground or down storm drains. In recent years, however, the rinse water used to clean the pour chutes is considered a potential groundwater contaminant. Consequently, environmental laws generally prohibit the disbursal of such rinse waters onto the ground, onto streets, or down storm drains. All such rinse waters must be recouped and recycled without being allowed to flow into streets, storm drains or gutters or allowed to percolate into the soil.
One way that has been used to deal with concrete mixture rinse waters at large construction sites has been to deposit such rinse waters in a prefabricated lined evaporation pit. However, the construction of a prefabricated evaporation pit at smaller commercial and residential construction sites is impractical and not cost effective.
There are various devices and systems for removal of concrete chute rinse water in the delivery vehicle. Many systems require the use of expensive and bulky hydraulic, pneumatic or electrical components which must be carried on the delivery vehicle. Such hydraulic or electrical components are expensive to purchase and maintain and awkward to carry on the delivery vehicle. Also, such hydraulic, pneumatic or electrical components leave the driver of the delivery vehicle vulnerable to hydraulic, pneumatic and electrical system failures which would prevent use of the equipment at the construction site. Still further, proposed equipment in the prior art can suffer from leakage of contaminated water during the normal operation. Many prior devices and methods require the use of the vehicle's mixing drum to store the recovered rinse water. Storing such rinse water in the mixing drum can adversely affect the integrity of the next load of concrete mixture prepared and transported within the mixing drum, unless the rinse water is thoroughly drained from the mixing drum prior to the preparation of the next batch of concrete mixture. From a practical standpoint, this is a major disadvantage of such proposed equipment because there is a strong temptation among individual concrete mixture preparation personnel to reuse the rinse water (already in the mixing drum) rather than to take the time to thoroughly drain and reconstitute the rinse water and to replace it in the mixing drum with fresh water.
The co-inventor's prior patented apparatus, covered by U.S. Pat. No. 7,117,995, avoids many of these problems by using a purely gravity fed system comprising a first, opened container for collecting the washed off concrete slurry that is suspended from the concrete chute, a second closed collection container for collecting grey water collected from the first container, and a transfer conduit for gravity feeding of the grey water from the first to the second container. While this system is excellent, there are some situations wherein the volume of grey water to be collected is not excessive, and it would be beneficial to provide a more simplified and lower cost apparatus and method.
Accordingly, there is a need for a vehicle-mounted apparatus and method for collection of wet concrete residue from dispensing elements of concrete delivery vehicles.
The invention is an apparatus and method useful in the separation of solids from a diluted, wet concrete mixture. The apparatus and method is suitable for use on a concrete mixture delivery vehicle. An apparatus for the collection of wet concrete residue that results from rinsing of a concrete dispensing element of a concrete delivery vehicle, the apparatus comprising:
a container body having an internal volume with an open top and a back wall and side wall;
a shield guard that extends above a back and at least portions of the side walls of the container body;
a containment cover that is hingedly attached to the container body and which permits the containment cover to open between a full opened position where the open top of the container body is accessible, and a fully closed position wherein the container cover water tightly closes the open top of the container body
a drain valve connected to the container body to control flow of liquid out of the container body;
a strainer associated with the drain valve which prevents aggregate from being drained through the drain valve; and
suspension engagements for suspending the apparatus on a concrete dispensing element of a concrete delivery vehicle.
An apparatus for the collection of wet concrete residue that results from rinsing of a concrete dispensing element of a concrete delivery vehicle, the apparatus comprising:
a container body having an internal volume with an open top and a back wall and side wall;
a shield guard that extends above a back and at least portions of the side walls of the container body;
a containment cover that is adapted to cover the open top of container body;
a drain valve connected to the container body to control flow of liquid out of the container body;
a strainer associated with the drain valve which prevents aggregate from being drained through the drain valve; and
hooks for suspending the apparatus on a concrete dispensing element of a concrete delivery vehicle.
The invention further comprises a method for the collection of and disposing of cement waste from the chute of a concrete delivery vehicle, comprising:
hanging the collection apparatus by its hooks on an end of a concrete delivery vehicle's concrete chute;
washing down the chute so that waste concrete including concrete grey water and aggregate located on the chute is deposited into the apparatus, and not necessary in the following order:
using the containment cover to cover and seal closed the open top of container body of the collection apparatus;
removing the collection apparatus from the end of the chute and securing it to the concrete delivery vehicle; and
transporting the collection apparatus back with the concrete delivery vehicle to a location where concrete grey water is drained from the apparatus and aggregate is emptied from the apparatus.
The following discussion describes in detail one embodiment of the invention and several variations of that embodiment. This discussion should not be construed, however, as limiting the invention to those particular embodiments. Practitioners skilled in the art will recognize numerous other embodiments as well.
The volume of the container base 12 is preferably between about 5 gallons and about 15 gallons, and for easy handling (since fresh water weights 8.35 pounds or 3.8 kg), should preferably not be over 8 to 10 gallons. Typically, the top opening 29 of the base container 12 has a width between about 10 inches and about 20 inches, and more preferably about 14 inches, and a depth typically between about 10 inches and about 20 inches, and more preferably about 14 inches. The height of the container portion 12 can be between about 8 inches and 20 inches, and preferably about 15 inches. For ease of handling, the apparatus 10 can be made of lightweight yet strong and durable materials so its less than about 20 to 25 pounds.
In operation and method of the invention, after concrete is delivered from the mixing drum 72 and down the chute, and no more concrete is needed, there will remain a considerable amount of concrete residue on the chute 70. If this concrete were to be left unattended on the chute 70, and the concrete deliver vehicle 74 attempted to drive away, concrete would spill on roadway and the remaining concrete on the chute would cure and interfere with smooth delivery of future loads of concrete from the chute 70. Accordingly, concrete delivery drivers will invariably rinse the chute 70 will a hose to remove concrete. As noted above, in the past, many drivers would simply allow the rinse water, which is full of cement and aggregate to fall onto the ground, roadways, or flow down sewers and storm drains, which is highly polluting. Using the apparatus and method of the invention, after an operator of the concrete delivery vehicle has completed delivering concrete, any loose and excess concrete is first scraped off the chute 70 and collected on a pile as waste concrete, typically on a pile at the job site. After that, the operator will suspend the apparatus 10 by its hooks 42 on the end of the chute 70 (which has complementary suspension points) of a concrete delivery vehicle 74, with the containment cover 28 in an opened position with the back wall 24 of the shield guard 21 facing the end of the chute 70 so that the concrete being rinsed will not splash outside of the apparatus 10. The operator will ensure that drain valve 46 is closed. The operator will then rinse the chute and related parts with a stream of water (e.g., from a hose), and allow the rinsed grey water and any aggregate to be rinsed into the container body 12 of the apparatus 10. After the chute is thoroughly rinsed and is clean, the operator will close the containment cover 28 to secure the contained grey water and aggregate in the container body 12, and will lift and remove the apparatus from the end of the chute 70. The operator will then place the apparatus 10 and its contents on the rack 76 and secure it for travel back to the concrete delivery vehicle's 74 base of operation, e.g., a ready mix facility. At the concrete ready mix facility, the grey water will be drained from the apparatus 10, e.g., by opening the drain valve 46, and if desired, can be recycled back into future loads of concrete to be mixed. The aggregate and other solids that are collected in the container body 12, can then be dumped out of the apparatus 10 and if desired, reused.
Unlike prior art systems that require pumps and drain lines that connect containers, with the current invention, the container body 10 both collects the grey water and aggregate from the chute being rinsed and also permits easy carrying and handling of the collected liquids and solids back to the concrete delivery truck's base of operation.
The invention provides for a simple and efficient method of dealing with waste concrete mix residue without the need of expensive, bulky and difficult to maintain electrical and/or hydraulic components. The incorporation of a lid with the apparatus alleviates problems of spillage after the collection of grey water and provides a quick and easy solution for a vexing problem.
Having thus described the invention, it should be apparent that numerous structural modifications and adaptations may be resorted to without departing from the scope and fair meaning of the instant invention as set forth hereinabove and as described hereinbelow by the claims.
