The present disclosure relates to the field of mixers and mixing systems, and in particular to a mixer and system for mixing an additive into a semi-solid material.
The cost of handling, transporting and disposing of semi-solid material in comparison to solid material is considerably higher, generally due to the specialized equipment required for safe handling. For example, a truck used to haul semi-solid material will require a sealed box to avoid seepage leaks, and will generally be fitted with a sealed top/cover to stop splashing liquid during transport. It is also generally known that landfill costs are higher for products that will not pass a liquids consistency test, for example a slump test or paint filter liquids test. Transporting solid material to a landfill is more environmentally sound as incidents during transport (i.e. vehicle rollover) are generally easier to manage. Compared to solids, liquids and semi-solid materials that spill during transport can have devastating environmental effects due to ease of spreading, as well as leaching into the ground.
Methods to convert liquid and semi-solid material into solid form suitable for disposal as conventional solid waste are known. Such methods involve the mixing of an additive to the liquid or semi-solid material to promote solidification. Traditional mixing/blending methods require batch mixing with devices such as pug mixers, mixing augers, or excavators/loaders that physically maul the two products together in a pit, tank or on the ground surface. With these traditional methods, “overdosing” is quite common, generally to address and compensate for poor mixing and clumping of the additive. In addition, the introduction of the additive to the semi-solid material is often complicated by dust issues that in itself presents a variety of health and safety concerns.
According to an aspect of the disclosure, provided is a mixing apparatus. The mixing apparatus comprises a housing defining a primary chamber, an inlet for receiving material into the mixing apparatus, as well as an outlet for discharging material from the mixing apparatus. The housing provides within the primary chamber a plurality of rotating shafts, each rotating shaft having a plurality of flailing fixtures associated therewith.
According to another aspect of the disclosure, provided is a mixing system comprising a material bulk hopper, a treatment additive hopper, and a premix chamber configured to receive material discharged from both the material bulk hopper and the treatment additive hopper, the premix chamber providing a premix action to the combined material and treatment additive. The combined material and treatment additive from the premix chamber is discharged from the premix chamber into a mixing apparatus, the mixing apparatus having a primary chamber configured with a plurality of rotating shafts having a plurality of flailing fixtures associated therewith.
According to another aspect of the disclosure, provided is a process for mixing a treatment additive into a semi-solid material. The process comprises transporting the semi-solid material from a containment structure and introducing it into a mixing apparatus. Adding to the flow of semi-solid material being added to the mixing apparatus a treatment additive. Subjecting the combined semi-solid material and treatment additive to a mixing action that disrupts the semi-solid material to allow the treatment additive to incorporate into the semi-solid material at a particulate size level, the mixing action including a fracturing action.
The foregoing and other features and advantages will be apparent from the following description of the disclosure as illustrated in the accompanying drawings. The accompanying drawings, which are incorporated herein and form a part of the specification, further serve to explain the principles of the disclosure and to enable a person skilled in the pertinent art to make and use the disclosure. The drawings are not to scale.
Specific embodiments of the present disclosure will now be described with reference to the Figures, wherein like reference numbers indicate identical or functionally similar elements. The following detailed description is merely exemplary in nature and is not intended to limit the disclosure or the application and uses of the disclosure. A person skilled in the relevant art will recognize that other configurations and arrangements can be used without departing from the scope of the disclosure. Although the description and drawings of the embodiments hereof exemplify a mixing apparatus and system as applied to mixing semi-solid material for the purpose of waste disposal, the disclosure may also be used in other mixing applications, for example in industrial manufacturing processes. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding technical field, background, brief summary or the following detailed description.
Provided is a mixing apparatus and system designed to take a semi-solid material (i.e. a high viscous or non-pumpable sludge) and blend it with a treatment additive or reagent to absorb and capture as much liquid as possible, thereby creating a drier, low slump final product. The desired low slump final product should be sufficiently dry to be suitable for conventional solid waste disposal.
Turning now to
Rotating shafts 28a, 28b, 28c are power driven (for example by gears, belts, chains, motors or a combination thereof) in such a way to rotate at variable speed(s) and predetermined direction(s). For example, having regard to the perspective shown in
As seen in
It will be appreciated that a variety of mixing apparatus configurations are possible in addition to that exemplified in
Rotating shafts 128a, 128b, 128c, 128d, 128e are power driven (for example by gears, belts, chains, motors or a combination thereof) in such a way to rotate at variable speed(s) and predetermined direction(s). For example, shafts 128a, 128b, 128c, 128d may rotate in alternating clockwise/counter-clockwise direction, while shaft 128e may rotate in either direction. In such an arrangement, having regard to the view shown in
As seen in
Turning now to
Rotating shafts 228a, 228b, 228c, 228d, 228e are power driven (for example by gears, belts, chains, motors or a combination thereof) in such a way to rotate at variable speed(s) and predetermined direction(s). For example, shafts 228a, 228b, 228c, 228d, 228e may rotate in alternating clockwise/counter-clockwise direction. In such an arrangement, having regard to the view shown in
As seen in
To facilitate movement of material within flail box 210, there may also be provided within housing 220 a conveyor means 250 (i.e. a belt conveyer, screw conveyer, bucket) arranged to direct material collecting towards the bottom of primary chamber 226 towards outlet 224. Alternatively, the bottom wall of primary chamber 226 may be sloped towards outlet 224 to promote movement of material.
It will be appreciated that other configurations for flailing box 10, 110, 210 are possible and may be suitably implemented to achieve a desired mixing behavior/performance. For example, the flail box may have a greater number or lesser number of rotating shafts than the examples detailed above. It is also possible to have a flail box with solely horizontal rotating shafts, or solely vertical rotating shafts or various combinations of horizontal and vertical shafts to achieve a desired mixing performance. The rotational direction and/or speeds may also be set and/or adjustable to achieve a desired performance.
Flail box 10, 110, 210 is suited for use in mixing a semi-solid material with a second material. The second material may be any secondary additive, such as a treatment additive. Suitable treatment additives include dry, liquid and semi-solid treatment additives. For the following discussion, the second material is regard to as a dry additive. Flail box 10, 110, 210 serves to disrupt the semi-solid material to allow the dry additive to mix/blend and incorporate into the semi-solid material with reduced clumping of the semi-solid material and/or the dry additive. In some embodiments, the disruption of the semi-solid material and dry additive targets a particulate (dust) size level. Disruption with flail box 10, 110, 210 presents as a fracturing action that promotes large particulates to be fractured/split into smaller particulates for better surface contact with the dry additive. Balling and clumping of both semi-solid material and dry additive are reduced, thus reducing the amount of dry product used and wasted.
While flailing box 10, 110, 210 may be provided as a separate standalone mixing apparatus, it may also be associated with additional operating components of a larger mixing system. For example, shown in
It will be appreciated that a flailing box design (for example one of flailing box 10, 110, 210) may be incorporated into a larger mixing system. Mixing systems contemplated here provide efficient processing/mixing of semi-solid material and dry additive in a continuous real time operation as opposed to a batch process. By achieving a homogeneous well-blended and proportioned mix, less dry additive will be needed, thus reducing the cost of the dry additive used and reducing the final total weight and volume of the solid to be disposed of
It will be appreciated that multiple configurations of the mixing system are possible. In one exemplary configuration, the basic process is generally comprised of 1) moving the semi-solid material from a containment structure (pit, pond, or tank) to the main mixing unit, 2) weighing the input semi-solid material or using a volumetric calculation, as it enters the mixing unit, 3) metering of the dry additive into the mixing unit, and incorporating it into the semi-solid material flow, 4) rapid shearing and mix/blending of the dry additive into the semi-solid material, and 5) final handling or processing stage for the appropriate and adequate finished end product.
One exemplary embodiment of a mixing system for mixing a dry additive into a semi-solid material is shown in
Although not shown, the means by which semi-solid material M is delivered to powered material hopper 513 may take on a variety of forms. For example, semi-solid material M may be excavated from a holding tank or pit by means of a mechanical bucket, such as a hydraulic excavator or loader, a vacuum truck, or any other suitable method for handling viscous material.
Provided at discharge end 517 of conveyer 515 is a premix chamber 519 configured to receive both semi-solid material M and the dry additive A delivered via powered material hopper 513.
As semi-solid material M is deposited into premix chamber 519, a predetermined amount of dry additive A is also introduced via conduit 523. For example, the desired amount of dry additive A is pre-established on the basis of a preliminary small-scale test where an optimal ratio of dry additive to semi-solid material M is determined. Secondary conveyor 521 combines the two together as it carries them to discharge conduit 525. By virtue of enclosure 527, dust from dry additive A is contained within premix chamber 519.
Premix chamber 519 may be configured to determine the weight or volume of the incoming semi-solid material M to coordinate flow with the proper ratio of dry additive A. Examples of this might include but not limited to installing load cells, monitoring torque of the ribbon auger, or other mechanical or electrical devices used for this purpose.
On determining the proper mix ratio dry additive A is accurately metered into the semi-solid material M by a means of a suitable mechanism, for example auger 529 provided on dry additive hopper 531. The size and speed of auger 529 would determine the amount of dry additive A leaving dry additive hopper 531 for mixing into semi-solid material M. As an alternative to auger 529, a variety of different types of metering devices such as, but not limited to, manual, air, or vacuum methods are available that could be used to meter in the dry additive.
The combined semi-solid material M and dry additive A mixture is then premixed and transported via secondary conveyor 521 to discharge conduit 525 of premix chamber 519, where it falls by gravity through inlet 22 of flail box 10, into primary chamber 26 and the action of the rotating shafts 28a, 28b, 28c contained therein. As detailed previously, the flail box serves to disrupt semi-solid material M to allow dry additive A to mix/blend and incorporate into semi-solid material M at a particulate (dust) size level. This action allows large particulate to be fractured/split into smaller particulate for better surface contact with the dry additive. Balling and clumping of both semi-solid material and dry additive are reduced, thus reducing the amount of dry product used and wasted.
On discharge through outlet 24 of flail box 10, the final blended mixture X is collected and removed. In the embodiment shown, mixing system 10 implements a transporter 533 (i.e. a belt conveyer, screw conveyer, or bucket) to direct blended mixture X from outset 24 to its final destination (i.e. a holding pit or disposal transport truck), or in certain treatment regimens, secondary processing. Secondary processing may include, but is not limited to processes that change the solidified mixture's structure, texture, moisture content and/or physical characteristics. For example, to quickly reduce moisture content and/or destroy pathogens, bacteria, or foreign substances that are unfavorable in the final product, blended mixture X may be subject to a heat source such as a flame, induction heating or microwaves. Blended mixture X may also be subject to tumbling in a rotary drum to turn the solidified mixture into smaller compacted “balls” thus creating a large surface area per ball to allow air drying or to benefit from the above mentioned heat process. Blended mixture X, now present in a substantially solidified form, can now be handled in such a way to be extruded, compressed, spread, bagged, or combined with other low moisture ingredients. In this form, blended mixture X may be handled as a solid, permitting for conventional solids disposal.
Dry additives suitable for use in the aforementioned mixing system 10 may be of the type designed to encapsulate any hazardous waste contained in the semi-solid material or liquid portion thereof. A non-limiting example of additives includes polymer/bentonite blend, sawdust, Portland cement, lime, fly ash, zeolite, other dry products already in use, and combinations thereof Although the mixing apparatus and system have been described and exemplified having regard to dry additives being used for treatment of the semi-solid material, the mixing apparatus and system may also be used with other treatment additives, for example liquid additives or semi-solid additives. For example, the mixing apparatus and system may be used with a wet portland cement- type additive. Where a liquid additive or semi-solid additive is used, a suitable treatment additive hopper may be used in place of the dry additive hopper.
It will be appreciated that the assembly of components as shown in
It is important to note that the construction and arrangement of the features in the various exemplary embodiments is illustrative only. Although only a few embodiments have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g. variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter herein. For example, elements shown as integrally formed may be constructed of multiple parts or elements, the position of elements may be reversed or otherwise varied, and the nature or number of discrete elements or positions may be altered or varied. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. Other substitutions, modifications changes and omissions may also be made in design, operating conditions and arrangement of the various exemplary embodiments without departing from the present scope of the disclosure. It will also be understood that each feature of each embodiment discussed herein, and of each reference cited herein, can be used in combination with the features of any other combination. All patents and publications discussed herein are incorporated by reference herein in their entirety.
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 62/197,957 filed 28 Jul. 2015, which is hereby incorporated by reference in its entirety for all purposes.
Number | Date | Country | |
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62197957 | Jul 2015 | US |