Bag press feeder assembly

A material handling apparatus is described comprising a material press body having an inlet and an outlet; a power source for generating an airstream into the inlet of the material press body and through the outlet of the material press body, wherein the airstream captures and feeds a supply material into the material press body; a plurality of press augers for capturing and manipulating the supply material into the material handling apparatus; and a drive system connected to drive and control the plurality of augers.

BACKGROUND

Field of the Invention

The present invention relates generally to a device for heat exchanged technology. More particularly, it relates to an apparatus that is part of a re-useable fuel processing unit for recycling plastic materials into refined fuel.

Background of the Invention

The use of feeder airlock systems in re-useable energy apparatus is known. Examples of known devices include U.S. Pat. No. 5,762,666 to Amrein et. al, U.S. Pat. No. 3,151,784 to Tailor, and U.S. Pat. No. 3,129,459 to Kullgren et. al. These patents teach airlocks with side gates (Amrein et. al.), a rotary feeder to an airlock using vanes (Tailor), and an extruder using electric heat (induction) (Kullgren). The Tailor device teaches a rotary style apparatus in which steel vanes are mounted to a shaft and spin inside a machined round housing. An opening is in the top and bottom of the housing to allow material to flow in and out of the housing. The vanes block the difference pressures between the inlet and outlet. However, multiple limitations exist within this design. A first limitation is that the prior art re-useable energy apparatus will not tolerate heat as the disclosed structural design of the prior art will expand and allow internal pressures to leak outwardly. Another limitation is that the vanes act as pockets and also carry the atmosphere from the inlet to the outlet. A third limitation concerns the rotation velocity. The rotation velocity must be slow to allow time for the material to fall out of the discharge or material will be carried back around and prevent refill from the inlet. A fourth limitation is that prior art devices will not allow for a molten material, e.g., such as hot plastic, to traverse therethrough.

The Amrein device discloses a feeder airlock system using two valves, with a hopper or pipe between them to allow material fill. Although this design tolerates heat, it allows the atmosphere to enter the feeder from the inlet and pass through to the discharge. The Amrein device, however, is limited in that the device does not allow atmospheric gases in some processes as they will cause problems downstream. Another limitation with this device includes the incapability for allowing molten material, such as hot plastic, to traverse therethrough.

The Kullgren device discloses an induction heated extruder. Kullgren describes an extruder that employs induction heating with the use of electric coils. Limitations with this apparatus include lacking an ability to create an airlock within its system. Thus, the described system is not conducive to allowing continuous feeding of plastic material(s). Additionally, the system of Kullgren requires a thick long barrel that requires very high horsepower to achieve an internal pressure along with the required heat necessary to melt plastic material. Hence, the device of Kullgren drives up operating costs and expenses due to its high power requirement.

Processing plastic type materials, such as plastic bags, in conventional prior art systems is known to be problematic. For example, due to the characteristically light weight nature of the plastic type materials, difficulties exist for processing and feeding the same into an extruder. For instance, plastic bag materials possess an extremely low non-compressed weight averaging three pounds per cubic foot and, due to their aforementioned light weight characteristics, plastic bag materials have a tendency to spring open, float when moved and form a very large bridge when stored.

Thus, the prior art does not readily provide continuous feeding and conveying of heated plastic materials. Additionally, the prior art does not easily provide systems for addressing recycled plastic materials for conversion into to refined fuel products. Furthermore, prior art systems prove problematic in achieving an air lock for feeding and manipulating heated plastic materials for subsequent processing.

Therefore, there is a need for producing a more efficient re-useable energy apparatus that provides capability for processing plastic type materials into usable and/or re-usable fuel products.

SUMMARY

According to first broad aspect, the present invention provides a material handling apparatus comprising a material press body having an inlet and an outlet; a power source for generating an airstream into the inlet of the material press body and through the outlet of the material press body, wherein the airstream captures and feeds a supply material into the material press body; a plurality of press augers for capturing and manipulating the supply material into the material handling apparatus; and a drive system connected to drive and control the plurality of augers.

DETAILED DESCRIPTION OF THE INVENTION

Definitions

For purposes of the present invention, the term “comprising”, the term “having”, the term “including,” and variations of these words are intended to be open-ended and mean that there may be additional elements other than the listed elements.

For purposes of the present invention, directional terms such as “top,” “bottom,” “upper,” “lower,” “above,” “below,” “left,” “right,” “horizontal,” “vertical,” “up,” “down,” etc., are used merely for convenience in describing the various embodiments of the present invention. The embodiments of the present invention may be oriented in various ways. For example, the diagrams, apparatuses, etc., shown in the drawing FIG.s may be flipped over, rotated by 90° in any direction, reversed, etc.

For purposes of the present invention, a value or property is “based” on a particular value, property, the satisfaction of a condition, or other factor, if that value is derived by performing a mathematical calculation or logical decision using that value, property or other factor.

For the purposes of the present invention, the term “de-stoner hood” refers to a device that separates solid heavy objects from entering a prescribed area. In one exemplary embodiment, the de-stoner hood may be configured to prevent heavy objects like steel or aluminum from entering into the bag press hopper of the disclosed embodiment.

For the purposes of the present invention, the term “identical” refers to being similar in every detail; exactly alike.

Description

While the invention is susceptible to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the drawings and will be described in detail below. It should be understood, however that it is not intended to limit the invention to the particular forms disclosed, but on the contrary, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and the scope of the invention.

Plastic waste material may be shredded and fed, for example, into a reactor (e.g., a pyrolysis reactor). Applying heat above 350 degrees Celsius will cause the shredded plastic material to melt and vaporize. Ultimately, an up-stream reactor may utilize back pressure to assist in the thermal cracking of carbon chains present in the plastic material to produce a refined fuel or re-useable fuel for subsequent use.

This application relates to an apparatus that may be part of a re-useable fuel processing unit. In one disclosed embodiment, an apparatus assembly may be used to feed plastic material into a reusable fuel processing unit including a pneumatic feed having a blower as a power source. It should be appreciated that the blower may be powered by the heat used to melt and vaporize the shredded plastic. The assembly may also include a screened air outlet, a plurality of press augers, a pinch conveyer system, a de-stoner hood, a receiver hopper, a low and high level indicators, ram, press screw inlet, pneumatic air cylinder, bag press inlet, outlet, and amp monitor. The pneumatic feed may be configured to move the plastic material at a fixed rate to the press feed receiver. The blower is used as a power source in which air from the blower is pulled through a screened hood. The screened air outlet may be substantially configured as the same identical shape as the bag press body. The press screw augers wipe the screen as they rotate allowing air flow through the bag press, ram, and receiver. A pinch conveyer system collects loose plastic material(s), such as plastic bags, and compresses them into a de-stoner hood (having a comparatively large body) allowing compressed plastic material(s) (e.g., plastic bags) to expand when disposed inside the de-stoner hood. The plastic material(s) (e.g., plastic bags) are conveyed into a receiver hopper thereby triggering a level indicator and starting a ram mechanism. The ram acts as an air cut-off gate that will push material into a press screw inlet. Once the ram starts to move, the pinch conveyer stops, thereby preventing material from entering the receiver hopper. Thus, the ram also acts as a cut-off gate. In a disclosed embodiment, the ram is pushed by a pneumatic air cylinder towards the bag press inlet. The ram may be configured to be larger than the receiver opening and designed with substantially the same identical matching face as the press screw augers. Full details of described embodiments are provided below.

Turning toFIG. 1, a disclosed embodiment of a heated airlock feeder or system1000is illustrated showing an apparatus in which the shredded plastic material is fed into a reactor (such as a pyrolysis reactor). The disclosed bag press feeder assembly200may be employed as part of a re-useable fuel processing unit that is readily configured for continuously feeding recycled plastic materials and heating the same for subsequent processing into a fuel source, as described below.

Plastic bag type materials are known to be difficult to process feed into conventional prior art systems due to the inherent light weight nature of their material design. Such plastic bag type materials may possess a very low non-compressed weight averaging, for example, approximately three pounds per cubic foot. Furthermore, such aforementioned materials may have a tendency to spring open, float when moved and form a very large bridge when stored. Embodiments of the disclosed design address and solve previous problems related to plastic bag conveying, receiving, storing and feeding and as described above.

The disclosed bag press feeder assembly may be constructed from a variety of materials. Carbon steel may typically be employed in the disclosed design, but other alloys may be applied if required by certain conditions. Stainless steel or aluminum may also be employed within a construction design. Turning toFIGS. 2 and 3, the design of the bag press feeder assembly200allows light materials to be collected and compressed into a higher density material. The inlet81of the unit is tangential to help allow the separation of the conveying air from the material. Eliminating air from within the disclosed design is important to remove or drastically reduce opportunities for combustion in an otherwise flammable working environment.

The plastic material being collected into the receiving hopper82is built to a point that a photo eye will indicate the level of material. This indicator will transmit a signal to a controller to stop the flow of material when capacity is indicated. In one disclosed embodiment, a ram press is configured to pull material from receiving hopper82into a ram housing or press chamber84, as material is lowered below the photo eye, more material is conveyed into receiving hopper82.

Plastic material may enter in either a clockwise or counterclockwise rotation based on a required design. As plastic material enters and circulates in the upper section of the receiver, it drops, due to gravity, into the lower section. This section is designed to allow material to continuously fall and not bridge. The upper diameter is smaller than the base discharge area creating a negative wall that forces any materials that would swell and cause bridging to be pushed in a downward direction following the sidewall shape.

Below the receiving hopper depicted onFIG. 2at82is a square housing lined with ultra-high-molecular-weight polyethylene (UHMW) or low friction plastic, that has a void filling ram device88inside. In one disclosed embodiment, the housing is configured as a square geometry. Ram device88is powered by a pneumatic air cylinder-. In some embodiments, ram device88may be conceptualized as a ram plug, for example, configured to travel inside the polymer liner91in a linear direction. The press chamber84is of a prescribed shape (e.g., a generally square shape profile) with external support bars and matching connection flanges or seal flanges86and an inlet or connecting flange83. A polymer liner, UHMW or nylon, is used to reduce the drag of the ram device88as it is pushed.

Air cylinder89is mounted to a support frame85at the tail of the press chamber depicted onFIG. 2at84. The other end of the air cylinder is connected inside ram device88, e.g., to a plate that matches the auger's profile. The back end of the press chamber84is sealed to prevent air leakage with a seal plate87. By sealing the chamber, air movement is allowed to enter into the receiving hopper at the product inlet port81, through press chamber84, through the press body, and then through the air discharge hood100and into a fan that can be located remotely. In some disclosed embodiments, air discharge hood100may be screened and serve as a screened air outlet transition hood.

The movement of ram device88slides beyond the opening depicted at301, allowing material to fall from the receiving hopper82into press chamber84through the opening301at connecting flange83. Ram device88is pulled to the rear of press chamber84which allows for a large volume of material to drop in front of the RAM to be subsequently guided and pushed into the press device. Pneumatic cylinder89extends and pushes ram device88into an opening98of the bag press feeder202.

The bag press feeder202consists of a press body or vertical double body204with a matching inlet flange98and an air discharge hood100. Bag press feeder202connects to a support frame90and to a lower hopper that comprise split eccentric reducers all of which may be welded to match up to the body and to the single diameter discharge flange. Within press body204, counter rotating double flighted augers92,93may be disposed. Augers92,93are configured to receive and grab incoming material and manipulate the same to push the material to the lower hopper.

Augers92and93are located in a drum measuring approximately fourteen inches in diameter for each auger with heavy screw flight material welded solidly around the drum. The drum is designed as a lower tapered cone to match the bag press body shape. The drive shaft at94is supported and welded through the drum and extends into the gearbox96. Augers92and93are constructed where one has right-hand rotation the other has left-hand rotation. The left-hand and right-hand augers overlap. Due to this overlap augers92,93act as self-cleaning mechanisms while pushing the plastic material downward into the lower section of the bag press feeder hopper. The pressure within the bag press feeder202increases as material is forced from the large opening at the top of the bag press feeder into the lower small opening of the bag press feeder. An access door102is a plug type door used to maintain the internal shape. Plastic material is pulled into the receiving hopper at the product inlet81by a fan located on the backside of a screened air discharge hood100.

Main augers92and93may be configured as drum style augers. The concept of the drums is to have a large circumference preventing materials like plastic bags from wrapping completely around the drum. The disclosed design, along with overlapping, counter rotating auger flights prevents material from wrapping around the drum augers92,93. The base of the drum augers has two flights ending 180 degrees apart due to the double flights. Because the drum has flights on both sides that are 180 degrees apart, the force pressure downward does not deflect the drum auger when compressing material below.

As best illustrated inFIG. 3, a drive system may be provided to connect to and control augers92,93. The drive system may include a gearbox or drive mechanism96that may be powered, for example, by a helical gear motorized drive box or motor drive97. Drive mechanism96may be maintained, for example, within a drive housing. From inside the drive housing exits transfer shafts96d,spur gears96eseals and bearings. The use of a multitude of spur gears96e(e.g., four spur gears) reduces the overall size of the gearbox96. In operation, the centerline difference between the two augers92,93would otherwise require two large gears to meet in the middle, where the use of the four smaller spur gears makes the box smaller while maintaining equal force on all of the shafts.

Accordingly, in one disclosed embodiment, a pneumatic feed is used in the disclosed design to both move the plastic material at a fixed rate to the receiving hopper82and to remove any heavy objects. A standard blower may be used for the power source. The air from the blower is pulled through a screened air discharge hood100on a back side of a material press body or bag press body99. In one disclosed embodiment, the screened air discharge hood100tapers generally inwardly from a connection point onto a screened air outlet transition302may be configured as the same shape as the bag press body depicted at99creating a very small gap between augers92and93and the screen302. Augers92and93wipe the screen302as it rotates, allowing for air flow through the bag press, ram and receiver. Screen302maintains plastic material particles within bag press body99thereby preventing them from exiting at air discharge hood100. However, the design of the screen302also allows airflow through the bag press into the bag press body99and out through air discharge hood100to eliminate and/or greatly reduce an otherwise combustible operating environment.

A conveyor system, such as a pinch conveyor system, may be employed to collect plastic material, such as loose bags, and compress them into a size that will be feed into a de-stoner hood10. De-stoner hood10has a large body and allows the compressed plastic bag material to expand a little once disposed within inside the de-stoner hood. The bags are then conveyed into the receiving hopper82into the press chamber. The bags fill receiving hopper82to a fixed point triggering a level indicator. This will start ram device88disposed below to push material into the press screw inlet98. As ram device88starts to move, the pinch conveyor stops to prevent further material from entering the receiving hopper82. Ram device88also acts as an air cutoff gate as it covers the receiver opening305of receiving hopper82. Receiving hopper82has a negative wall design. The incoming material expands when it is inside the receiving hopper82. The hopper gets larger as its gets closer to the ram inlet at opening305. Ram device88is pushed by a pneumatic air cylinder89to the bag press inlet98, and at the same time cuts off the material flow due to its shape as the ram body is larger than the receiver opening305disposed above the ram body. Ram device88may be configured to have a substantially identical face with the same shape and/or size as the press screw augers92and93allowing material to be pulled into the press body99. The plastic material is forced down the augers92and93by the metal flights300. Disclosed embodiments provide one left hand flight auger92and one right hand flight auger93in the press body99..

As more and more plastic material, such as plastic bags, is collected into the bag press, the plastic material is forced down and is compressed. As the plastic material (e.g., plastic bags) builds up inside the bag press body99, the plastic material is pushed down where the diameter of the hopper gets smaller and smaller towards a compression area at outlet103. The increase in material and decrease in area creates a higher density of plastic material and creates a pressurized seal.

The bag press motor drive97may include an amp monitor. The amp monitor may be set at a prescribed level to signal when the bag press is full and at the correct pressure. Depending upon the threshold level of the amp monitor, the motor drive is controlled to operate or not operate based upon a prescribe value or amp range. When the material is allowed to discharge, the pressure is reduced in the compression area at outlet103and the computer may be initialized to start the fill process while continuing to monitor the motor amps.

Turning toFIG. 4, an alternate embodiment of a bag press feeder assembly is illustrated. A negative vacuum pressure is created within bag press body99of material handling apparatus400to draw plastic material within. Accordingly, plastic material402is feed into inlet404of bag press body99-by airstream406. The disclosed configuration receives airstream406into inlet404of bag press body99towards auger92(93) and through screen302and air discharge hood100.

A screened air outlet transition302may be configured as the same shape as the bag press body depicted at99creating a very small gap between augers92and93and the screen302. Augers92and93wipe the screen302as it rotates, allowing for air flow through the bag press, ram and receiver. Screen302maintains plastic material particles within bag press body99thereby preventing them from exiting through screen302and air discharge hood100. However, the design of the screen302also allows airflow through the bag press into the bag press body99and out through screen302and air discharge hood100to eliminate and/or greatly reduce an otherwise combustible operating environment.

By design, plastic material402is urged towards auger92(93) via airstream406and the back pressure created within bag press body99. As more and more plastic material402is collected into bag press body99, plastic material402is forced in downward direction408as it continues to compress. As plastic material402builds up inside bag press body99, plastic material402is pushed downwardly where the diameter of the hopper gets smaller and smaller towards the outlet. The increase in material and decrease in area creates a higher density of material and creates a pressurized seal.

Having described the many embodiments of the present invention in detail, it will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims. Furthermore, it should be appreciated that all examples in the present disclosure, while illustrating many embodiments of the invention, are provided as non-limiting examples and are, therefore, not to be taken as limiting the various aspects so illustrated.

All documents, patents, journal articles and other materials cited in the present application are incorporated herein by reference.