Method of de-packaging and treating organic waste

Abstract

System and process for de-packaging organic material and separating the organic material from the packaging. Once separated, the organic material is processed in a de-packaging machine to form an organic slurry that is directed from the de-packaging machine to an anaerobic digester. A programmed controller is provided for controlling the flow of the organic slurry to the anaerobic digester. The programmed controller is programmed to maintain the total suspended solids concentration of the organic slurry within a target range and when in the target range, the programmed controller is operative to direct the organic slurry to the anaerobic digester. If the total suspended solids concentration is outside of the target range, then the programmed controller is configured to initiate action that will bring the total suspended solids concentration of the organic slurry back within the target range.

Description

[0001] C&B Ref. No.: 5952-594

[0002] METHOD OF DE-PACKAGING AND TREATING ORGANIC WASTE

[0003] RELATED APPLICATIONS

[0004] This application claims priority to U.S. Provisional Patent Application Serial No. 63 / 680,257 filed on August 7, 2024, which is incorporated herein by reference in its entirety.

[0005] FIELD OF THE INVENTION

[0006] The present invention relates to de-packaging organic waste and thereafter biologically treating the de-packaged organic waste in Anaerobic Digestion.

[0007] BACKGROUND OF THE INVENTION

[0008] Various industries produce large amounts of organic waste which must be treated or disposed of consistent with applicable government and local regulations and at the same time in a way that is environmentally friendly and economical. One particular industry that produces large amounts of packaged organic waste is the food industry. Packaged food waste from restaurants, grocery stores and other places may include food not sold, food that has expired, or food that fails a quality standard. To deal with packaged food waste, the packages containing the food waste is typically collected and hauled to a site having a de-packaging machine.

[0009] A de-packaging machine or unit is designed to receive packaged waste and separate product (which in the case of food products is referred to as organic waste) from the packaging structure. Broadly speaking, this is sometimes referred to as separating inert material (the packaging) from organic material. Packaging containing organic waste along with water is fed into the de-packaging machine. Typically, the de-packaging machine employs mechanical means, such as rotating drums, paddles, augers, etc., that engage the packaging and break it apart and into pieces. Once the packaging structure has been broken apart, it is separated from the organic material and discharged from the de-packaging machine. The organic material that remains is subjected to a process which, in one example, includes grinding or crushing the separated organic material. Ultimately, the processed organic material and water form an organic slurry that is discharged from the de-packaging machine through openings, sieves, screens or the like.

[0010] Once the organic slurry is discharged from the de-packaging machine, it is typically conditioned and treated. Managing the de-packaging process and the subsequent conditioning and treatment of the organic slurry is typically left to a manual operator. He or she is left with controlling the feedstock directed into the de-packaging machine, as well as managing the conditioning of the organic slurry prior to downstream treatment. All of this is a time-consuming C&B Ref. No.: 5952-594 and costly endeavor, not to mention the inefficiencies and inconsistencies that are introduced by relying on manual operators.

[0011] The present invention aims to automate the de-packaging and organic slurry conditioning process so as to reduce labor costs, improve efficiency, and make the organic slurry conditioning process more consistent.

[0012] SUMMARY OF THE INVENTION

[0013] The present invention relates to an automatic system and process for de-packaging organic material and conditioning an organic slurry produced in the course of de-packaging the organic material.

[0014] In one embodiment, the present invention entails maintaining the total suspended solids concentration of the organic slurry in a target range prior to directing the organic slurry to downstream treatment.

[0015] Another aspect of the present invention entails continuously measuring the total suspended solids concentration of the organic slurry discharged from the de-packaging machine and taking steps to maintain the total suspended solids concentration of the organic slurry in a target range prior to directing the organic slurry downstream for treatment. When the measured total suspended solids concentration of the organic slurry exceeds the target range, steps are taken to recirculate the organic slurry through the de-packaging machine and dilute the organic slurry with water. This is done until the measured total suspended solids concentration is brought back within the target range. When the measured total suspended solids concentration of the organic slurry is less than the target range, the organic slurry is recirculated through the de-packaging machine and by further grinding the organic slurry in the de-packaging machine, the total suspended solids concentration is increased and ultimately brought within the target range.

[0016] Other objects and advantages of the present invention will become apparent from a study of the following description and the accompanying drawings which are merely illustrative of the invention.

[0017] DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic illustration showing a de-packaging machine and illustrating a system and process for controlling the total suspended solids concentration of an organic slurry produced by the de-packaging machine.

[0019] DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0020] With further reference to the drawing, the present invention relates to a system and process for de-packaging organic waste via a de-packaging machine 10 and in the process of C&B Ref. No.: 5952-594 de-packaging the waste there is produced an organic slurry. Once the organic slurry is produced, it is desirable to manage this waste. One approach is subjecting the organic slurry to an anaerobic digestion process which significantly reduces the volume of organic waste, thereby decreasing the need for landfill space and at the same time, the organic slurry can be a source of renewable energy production in the form of biogas. However, in many cases, the organic slurry produced in a de-packaging process is not immediately suitable for being directed into an anaerobic digester and there is a need to condition the organic slurry before being subjected to anaerobic digestion. In particular, there is a need to control the total suspended solids concentration of the organic slurry directed into the anaerobic digester. The concentration of total suspended solids in the anaerobic digester is important for optimal performance and efficiency. High total suspended solids concentrations can create dense sludge that makes the digester mixing difficult. Another impact of high concentration of feedstock is that organic loading rate which is another critical design and operational parameter. If the organic loading rate is exceeded then the pH of the digester drops rapidly and operation gets an upset condition. This can reduce the overall efficiency of the digestion process and stop biogas production. Moreover, when the total suspended solids concentration is above an optimum range, this tends to increase the solids content and impacts the digesters’ hydraulic retention time.

[0021] In this particular case, the goal is to maintain the total suspended solids concentration at a desirable target level which can vary depending on various factors such as the type of waste that produces the organic slurry. Generally speaking, it is desirable to maintain the total suspended solids concentration of the organic slurry in a target range of approximately 4-10% DS (Dry Solids). Therefore, the system and process of the present invention aims to maintain the total suspended solids concentration of the organic slurry in the target range by employing an automatic control system. When the total suspended solids concentration is below the target range, the control system reacts by recirculating the organic slurry through the de-packaging machine 10 and continues to grind the organic slurry to increase the total suspended solids concentration therein. On the other hand, when the total suspended solids concentration exceeds the target range, the control system recirculates the organic slurry through the depackaging machine, but also adds water to the organic slurry so as to dilute the organic slurry and reduce the total suspended solids concentration to where the total suspended solids concentration falls within the target range.

[0022] Before discussing the process for de-packaging organic waste and conditioning the resulting organic slurry, it is beneficial to briefly review the system depicted in Figure 1. Shown therein is a de-packaging machine 10. On the upstream side of the de-packaging machine 10 is a water inlet line 12. Water inlet line 12 includes a motorized control valve 14 and a flow meter 16. On the output side of the de-packaging machine 10 is an outlet line 18 through which the C&B Ref. No.: 5952-594 organic slurry flows once discharged from the machine. Line 18 leads to a slurry pump 20 which functions to pump the organic slurry from the de-packaging machine 10 via line 18 and therefrom to other parts of the system shown in Figure 1. Downstream of the slurry pump 20 is total suspended solids sensor 22. Sensor 22 is an online instrument with signal transmitting capability that continuously senses the concentration of total suspended solids in the organic slurry downstream of slurry pump 20. Details of the total suspended solids sensor 22 are not dealt with herein in detail because such sensors are widely used in the wastewater treatment field. Suffice it to say that some total suspended solids sensors rely on optical measurements to detect the presence and concentration of suspended solids in a liquid.

[0023] Downstream of slurry pump 20 is line 28 which directs the organic slurry to a motorized control valve 30 that is upstream of an anaerobic digester 32. Just downstream of slurry pump 20 is a T-junction where there is provided an organic slurry recirculation line 24. More particularly, as will be fully appreciated from subsequent portions of the disclosure, line 24, which includes another motorized control valve 26, functions during certain times in the process to recirculate the organic slurry back to the de-packaging machine 10.

[0024] Incorporated into the system shown in Figure 1 is a programmed controller 34. Programmed controller 34 is operatively connected to the total suspended solids sensor 22 via a signal line 36. Signals generated by the total suspended solids sensor 22 representative of the total suspended solids concentration of the organic slurry are directed through line 36 into the programmed controller 34. Signals from the flow meter 16, representative of the water flow into the de-packaging machine 10, is directed through line 46 to the programmed control 34. Output control signals are directed from the programmed controller 34 via lines 38, 40 and 42 to the three motorized valves 14, 26, and 30.

[0025] Programmed controller 34 is programmed to control the total suspended solids concentration of the organic slurry directed into the anaerobic digester 32. In particular, the programmed controller 34 is programmed to maintain a target total suspended solids concentration range in the organic slurry fed to the anaerobic digester 32. The target total suspended solids concentration can vary depending on the particular type or category of waste being de-packaged and other factors. In the example discussed herein, the waste de-packaged is an organic waste of the type found in packaged food. Generally speaking, for optimum efficiency in the anaerobic digester 32 and for efficient biogas production, the target total suspended solids concentration for the organic slurry is in the range of approximately 4-10% DS. This means that, in one example, the programmed controller 34 functions to maintain the total suspended solids concentration of the organic slurry downstream of valve 30 within the range of 4-10% DS.

[0026] The system and process described herein is capable of de-packaging various types or categories of waste. The particular category of waste may dictate how the process is carried C&B Ref. No.: 5952-594 out and controlled. For example, the optimum total suspended solids concentration may vary depending on the category of waste that is de-packaged by the de-packaging machine 10. As seen in Figure 1 , the interface of the programmed controller 34 includes a series of user inputs for different categories of waste, i.e. CAT 1 WASTE, CAT 2 WASTE, CAT 3 WASTE, etc. In one embodiment, the packaged waste to be fed into the de-packaging machine 10 is analyzed and categorized. Thereafter, the particular category of waste that is to be de-packaged is inputted into the programmed controller 34.

[0027] To initiate the process, the de-packaging machine 10 is loaded with packaged organic waste. As used herein, the term “organic waste” generally means a waste that is rich in carbon and which can be broken down by microorganisms and other biological processes. Further, an initial amount of water is directed through line 12 into the de-packaging machine 10. The water is held in an area of the de-packaging machine 10 apart from where the packaged organic material is initially held. Programmer controller 34 directs a signal via line 38 to the valve 14 to open the same and this results in water flowing through line 12 and the flow meter 16 into the de-packaging machine 10. Flow meter 16 senses the flow rate of water passing through line 12 and directs a signal via line 46 to the programmed controller. The programmed controller computes the volume of water directed into the de-packaging machine 10 and once the programmed volume has been reached, the programmed controller 34 closes valve 14.

[0028] De-packaging machine 10 is then actuated and the packaged organic material is engaged by mechanical means that breaks apart the packaging and through an initial process generally separates the broken packaged material from the organic material and discharges the broken packaged material from the de-packaging machine 10. De-packaging machine 10 then proceeds to grind the organic material that was formerly contained in the packages. The water initially directed into the de-packaging machine 10 is located in an area where it becomes mixed with the ground organic material. This mixture of ground organic material and water form the organic slurry that is pumped by pump 20 from the de-packaging machine 10.

[0029] The organic slurry flows from the de-packaging machine 10 through line 18 and is discharged from the pressure side of pump 20. Just downstream of the pump 20 is where the total suspended solids sensor 22 is located and it senses the total suspended solids concentration of the organic slurry at that point. The sensed total suspended solids concentration is directed via line 36 to the programmed controller 34. As long as the total suspended solids concentration is within the target range, the programmed controller 34 opens valve 30 while maintaining valves 14 and 26 closed. In this state, the organic slurry is directed through valve 30 and downstream to the anaerobic digester 32 where the organic slurry is subjected to anaerobic digestion.

[0030] In some cases, the sensed total suspended solids concentration may be below the target concentration. In that case, the programmed controller 34 closes valve 30 and continues C&B Ref. No.: 5952-594 to maintain valve 14 in a closed position while opening valve 26. Pump 20 then recirculates the organic slurry through line 24 back through the de-packaging machine 10. As the organic slurry and is circulated through the de-packaging machine 10, the machine continues to grind the organic material in the slurry and as a consequence increases the total suspended solids concentration through this recirculation process. Once the programmed controller 34 determines the total suspended solids concentration in the organic slurry is brought back within the target range, the programmed controller 34 will then close valve 26 and open valve 30, which will then allow the organic slurry to move through line 28, through valve 30 onto the anaerobic digester 32. In some cases, the sensed total suspended solids concentration sensed by the sensor 22 will exceed the target range. In this case, the programmed controller is programmed to dilute the organic slurry. This is achieved by the programmed controller closing valve 30 and opening valves 14 and 26. Hence, the organic slurry is circulated through line 24 back to the de-packaging machine 10 and simultaneously valve 14 is open and dilution water is directed through line 12 into the de-packaging machine 10 where it is mixed with the organic slurry. This effectively decreases the total suspended solids concentration of the organic slurry. This process is continued until the sensor 22 senses that the concentration of total suspended solids in the organic slurry is within the target range. When this occurs, the programmed controller 34 will close valves 14 and 26 and open valve 30 to allow the organic slurry to move through line 28, through valve 30 and downstream to the anaerobic digester 32.

[0031] There are many advantages to the system and process of the present invention. Compared to conventional approaches for conditioning organic slurries, the system and process of the present invention utilizes advanced sensing technology to deliver a more reliable and consistent organic slurry effluent. The organic slurry produced by the process of the present invention will consistently maintain the total suspended solids concentration of the organic slurry in a relatively tight range, which will in turn optimize the performance of downstream anaerobic digesters. The system and process of the present invention will also significantly reduce the need for manual operator intervention, resulting in lower labor costs. The precision of the present system and process insures that the total suspended solids concentration of the organic slurry is precisely controlled and when the concentration exceeds the target range, the system and process described herein will quickly and efficiently bring the total suspended solids concentration of the organic slurry within the target range. This will minimize unnecessary water consumption and will contribute to conservation efforts. With this automatic system and process for controlling the total suspended solids concentration of the organic slurry effluent, workers can allocate their time to other productive tasks, such as preparing the next batch of waste.

[0032] The present invention may, of course, be carried out in other specific ways than those herein set forth without departing from the scope and the essential characteristics of the invention. The present embodiments disclosed herein are therefore to be construed in all C&B Ref. No.: 5952-594 respects as illustrative and not restrictive and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.

Claims

C&B Ref. No.: 5952-594CLAIMSWhat is claimed is:1 . A method of biologically treating organic material contained in packaging, the method comprising: directing packaging containing the organic material to a de-packaging unit; directing an amount of water into the de-packaging unit; mechanically separating the organic material from the packaging and in the process producing an organic slurry containing at least some of the organic material; pumping the organic slurry to an anaerobic digester; maintaining the total suspended solids concentration of the organic slurry directed to the anaerobic digester within a target total suspended solids concentration range by: i. upstream of the anaerobic digester, sensing the total suspended solids concentration of the organic slurry; ii. if the sensed total suspended concentration of the organic slurry is within the target total suspended solids concentration range, then the method includes directing the organic slurry to the anaerobic digester; and iii. if the sensed total suspended solids concentration of the organic slurry is greater than the target suspended solids concentration range, then the method includes bringing the total suspended solids concentration of the organic slurry within the target total suspended solids concentration range by recirculating the organic slurry to the de-packaging unit and by adding water to the organic slurry.

2. The method of claim 1 wherein the target total suspended solids concentration range is approximately 4-10% DS.

3. The method of claim 1 including categorizing the organic material contained in the packaging, and maintaining the total suspended solids concentration of the organic slurry in the targeted total suspended solids concentration range based on the category of the organic material in the packaging.

4. The method of claim 1 wherein if the sensed total suspended solids concentration of the organic slurry is less than the target total suspended solids concentration range, the method includes recirculating the organic slurry through the de-packaging unit and grinding the organic material in the organic slurry until the total suspended solids concentration of the organic slurry is within the target range.C&B Ref. No.: 5952-5945. A system for de-packaging and treating organic material comprising: a de-packaging machine for separating organic material from packaging and processing the separated organic material to form an organic slurry; an anaerobic digester for anaerobically digesting the organic slurry; a piping and valve network operatively connected between the de-packaging machine and the anaerobic digester and including three or more flow control valves and a recirculation line; a pump for pumping the organic slurry from the de-packaging machine to and through the piping and valve network; a sensor integrated in the piping and valve network for measuring the total suspended solids concentration of the organic slurry passing through the piping and valve network; a programmed controller operatively associated with the piping and valve network and operatively connected to said sensor and to three or more flow control valves in the piping and valve network; and the programmed controller configured to: i. direct the organic slurry having a total suspended solids concentration within a target range to the anaerobic digester; ii. increase the total suspended solids concentration of the organic slurry by recirculating the organic slurry through the de-packaging machine and adding dilution water to the organic slurry if the sensed total suspended solids concentration of the organic slurry is greater than the target range; and iii. decrease the total suspended solids concentration of the organic slurry by recirculating the organic slurry through the de-packaging machine and grinding the organic material in the organic slurry if the sensed total suspended solids concentration of the organic slurry is less than the target range.

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