Dining table residue treatment method

Abstract

The invention belongs to the technical field of dining table residue treatment, and particularly relates to a dining table residue treatment method. The treatment method comprises the following steps: carrying out heat preservation treatment on the dining table residues; wherein the temperature ranges from 190 DEG C to 500 DEG C, the pressure is within 1 Mpa, bacteria and viruses (especially mad cattle disease viruses) in the residues on the dining table can be thoroughly killed within 2-40 min, and the explosion risk caused by previous high-pressure treatment is reduced; besides, compared with a treatment method recorded in an existing patent CN118437729A, the treatment method provided by the invention can thoroughly kill Ruan viruses such as mad cattle disease viruses, and the patent can only kill most viruses but cannot completely kill the Ruan viruses such as mad cattle disease viruses.

Description

Technical Field

[0001] The present invention belongs to the technical field of table leftovers treatment, and specifically relates to a method for treating table leftovers. Background Art

[0002] Table leftovers, also known as swill, are the leftover rice and dishes discarded in restaurants, dining halls, schools or unit canteens, etc. Due to the long storage time, the content of some bacteria in them is very high, and table leftovers are extremely prone to deterioration. Direct discharge will cause environmental pollution. The existing mainstream treatment methods are for combustion power generation or deep burial. The utilization rate of combustion power generation is low, and deep burial will cause waste of resources. Therefore, it is necessary to carry out green treatment and recycling of table leftovers to reduce or avoid their environmental pollution and improve resource utilization rate. Among them, feed processing of table leftovers is one of the existing green treatment methods for table leftovers. This treatment method has no pollution to the environment and high utilization rate of the treated materials.

[0003] And the feed processing of table leftovers requires the elimination of bacteria and viruses in table leftovers, especially the mad cow disease virus. As a typical prion, the misfolded protein structure of the mad cow disease virus shows extreme stability. When the mad cow disease virus was prevalent, the British expert group placed the mad cow disease virus in a high-temperature and high-pressure container at 360 degrees for 15 minutes and then took it out for cultivation, and it was still active. It can even survive for 48 hours in strong acid and strong alkali solutions. A large number of kitchen waste treatment stations were built in the first- and second-tier cities across the country 10 years ago, mainly to produce fertilizers and a part of feed from them. As fertilizers, due to the high salt content, it is easy to cause soil compaction after being used by farmers for a period of time, and gradually it is no longer accepted by farmers. As feed, after being tried in pig farms for a period of time, it was also stopped because the problem of animal homologous pollution, that is, the inactivation problem of the mad cow disease virus, has not been solved. Therefore, only after the bacteria and viruses in table leftovers are completely inactivated can they be safely used as feed.

[0004] The current mainstream technology for killing bacteria and viruses relies on high-temperature and high-pressure processes. For example, the existing patent CN118437729A, and such technologies have significant drawbacks: the high-pressure conditions require strict pressure resistance performance of the equipment, resulting in high equipment manufacturing costs and explosion safety hazards; the long treatment cycle greatly increases energy consumption and operating costs, restricting the large-scale treatment capacity. In addition, the high-pressure environment will accelerate the corrosion of the equipment, and frequent maintenance will further increase the burden on enterprises, making it difficult to meet the industry's requirements for economy and sustainability.

[0005] Therefore, it is urgent to develop a more efficient and safer method for treating table leftovers. Summary of the Invention

[0006] Based on the patent CN118437729A, the present invention conducts heat preservation treatment on the table leftovers by increasing the heating temperature (190°C - 500°C) and reducing the pressure (pressure within 1 Mpa), which can completely kill bacteria and viruses in the table leftovers (2h - 40min), especially the mad cow disease virus.

[0007] To achieve the above object, the present invention can adopt the following technical solutions:

[0008] On the one hand, the present invention provides a method for treating table leftovers, which includes: conducting heat preservation treatment on the table leftovers; wherein, the temperature is 190°C - 500°C, and the pressure is within 1 Mpa.

[0009] Preferably, in the above treatment method, the heat preservation treatment time is 2h - 40min.

[0010] Preferably, the above treatment method satisfies any one of the following conditions:

[0011] When the temperature is 190°C ≤ T ≤ 270°C, the treatment time is 2h - 1h40min;

[0012] When the temperature is 270°C < T ≤ 350°C, the treatment time is 1h40min - 1h20min;

[0013] When the temperature is 350°C < T ≤ 430°C, the treatment time is 1h20min - 1h;

[0014] When the temperature is 430°C < T ≤ 500°C, the treatment time is 1h - 40min.

[0015] Preferably, the above treatment method further includes: obtaining a mixture after conducting heat preservation treatment on the table leftovers, separating the mixture to obtain an upper layer and a lower layer, the upper layer is an oil layer, and the lower layer is an animal feed layer.

[0016] More preferably, the above treatment method further includes: separating the oil layer and removing the moisture and impurities in the oil layer.

[0017] Preferably, the above treatment method further includes: drying the sterilized and virus - killed lower layer.

[0018] Preferably, in the above treatment method, the table leftovers are subjected to crushing treatment before heat preservation treatment.

[0019] On the other hand, the present invention provides an application of the animal feed layer obtained after being treated by the treatment method in the present invention in being used as or preparing animal feed.

[0020] On yet another aspect, the present invention provides an application of the oil layer obtained after being treated by the treatment method in the present invention in preparing biodiesel.

[0021] The beneficial effects of the present invention include:

[0022] (1) The method for treating table leftovers provided by the present invention can thoroughly kill bacteria and viruses (especially mad cow disease virus) in table leftovers within 2h to 40min, and reduce the explosion risk brought by high-pressure treatment.

[0023] (2) The treatment method of Patent CN118437729A mainly puffs table leftovers to improve feed utilization rate. The best puffing effect and the most ideal economic value are the technical problems it solves, while the present invention is to completely inactivate mad cow disease virus. Therefore, the inactivation effect of mad cow disease virus in the present invention is better than that of Patent CN118437729A.

[0024] (3) The purpose of Patent CN118437729A is to puff table leftovers so as to be easily digested as feed and improve feed utilization rate. In order to achieve the best puffing effect, the holding time cannot be arbitrarily extended, so the sterilization and disinfection effects are not ideal. Because the input steam volume (water) will increase greatly with the extension of the holding time, and the increase in water vapor volume will directly affect the puffing effect and even fail to achieve the puffing purpose. Detailed implementation manners

[0025] The examples given are for better illustrating the present invention, but the content of the present invention is not limited only to the examples given. Therefore, those skilled in the art who make non-essential improvements and adjustments to the implementation manners according to the above-mentioned invention content still fall within the protection scope of the present invention.

[0026] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. Unless having significantly different meanings in the context, the singular forms of expressions include the plural forms of expressions. As used herein, it should be understood that terms such as "including", "having", "containing" are intended to indicate the existence of features, numbers, operations, components, parts, elements, materials or combinations. The terms of the present invention are disclosed in the specification, and are not intended to exclude the possibility of the existence or addition of one or more other features, numbers, operations, components, parts, elements, materials or their combinations. As used herein, depending on the situation, " / " can be interpreted as "and" or "or".

[0027] An embodiment of the present invention provides a method for treating table leftovers, which includes: performing heat preservation treatment on table leftovers; wherein, the temperature is 190°C to 500°C, and the pressure is within 1 Mpa.

[0028] It should be noted that the present invention is an improvement based on Patent CN118437729A. By increasing the temperature and reducing the pressure (the pressure is within 1 Mpa), bacteria and viruses (especially the mad cow disease virus) in the table leftovers can be completely inactivated within 2 h to 40 min. In this way, the demand for high-pressure containers and the explosion risk of high-pressure treatment are reduced, and the treatment efficiency is improved.

[0029] In addition, it should also be noted that when the present invention performs heat preservation treatment, a thermal oil boiler (electric heating thermal oil boiler) is used to replace the steam boiler in the existing treatment technology. Compared with the steam boiler, the heating effect of the thermal oil electric boiler is the same, and moreover, the water content of the treated material is reduced (in the past treatment method, the steam turning into water would cause a large increase in the water content of the treated material), reducing the subsequent drying difficulty and drying cost of the treated material. In addition, we select a thermal oil boiler with molten salt as the heating medium, which has a lower pressure (the highest is 1 MPa) and a higher temperature (it can reach 550 degrees). The thermal oil electric boiler is equipped with an automatic temperature and pressure regulation control switch, which is more convenient and energy-saving in operation.

[0030] In addition, it should also be noted that the thermal oil boiler works in an indirect heating mode. The heating oil is sent to the inner layer of the sterilization tank through a stainless steel conduit and adheres to the sterilization tank in the form of a spiral conduit. Through the operation of a pressure pump, the thermal oil circulates continuously, thereby transferring heat to the heated table leftovers. Through the circulation of the heating oil, the temperature of the table leftovers in the tank can be increased or maintained. Therefore, the table leftovers in the heating tank have little pressure, at most 1 Mpa. In addition, the pressure of the thermal oil system is relatively larger, up to 2.5 Mpa at most, but it is in another closed space, and there is an automatic adjustment switch, so the pressure is not considered either.

[0031] In some specific examples, in the above treatment method, the heat preservation treatment time is 2 h to 40 min.

[0032] It should be noted that the treatment method in the present invention can complete thorough sterilization and disinfection within 2 h to 40 min, such as 1 h 40 min, 1 h 20 min, or 1 h 10 min, etc.

[0033] In some specific examples, the above treatment method satisfies any one of the following conditions:

[0034] When the temperature is 190°C ≤ T ≤ 270°C (such as 200°C, 220°C, 250°C, or 260°C, etc.), the treatment time is 2 h to 1 h 40 min (such as 1 h 57.5 min, 1 h 52.5 min, 1 h 45 min, or 1 h 42.5 min, etc.);

[0035] When the temperature is 270 °C < T ≤ 350 °C (such as 290 °C, 310 °C or 330 °C, etc.), the processing time is 1 h 40 min to 1 h 20 min (such as 1 h 35 min, 1 h 30 min or 1 h 25 min, etc.);

[0036] When the temperature is 350 °C < T ≤ 430 °C (such as 370 °C, 390 °C, 400 °C or 420 °C, etc.), the processing time is 1 h 20 min to 1 h (the processing time is 1 h 15 min, 1 h 10 min, 1 h 7.5 min or 1 h 2.5 min, etc.);

[0037] When the temperature is 430 °C < T ≤ 500 °C (such as 450 °C, 470 °C or 490 °C, etc.), the processing time is 1 h to 40 min (such as 55 min, 50 min or 42.5 min, etc.).

[0038] It should be noted that in order to maximize the processing efficiency and reduce energy consumption, different processing times can be set according to different temperatures to achieve the optimal disinfection effect in the shortest time.

[0039] In some specific examples, the above processing method further includes: subjecting the table leftovers to heat preservation treatment to obtain a mixture, separating the mixture to obtain an upper layer and a lower layer, and the upper layer is an oil layer.

[0040] It should be noted that the lower layer is in a viscous state and mainly contains table leftovers, and can be used as feed after treatment.

[0041] In some specific examples, the above processing method further includes: separating the oil layer and removing the moisture and impurities in the oil layer.

[0042] It should be noted that the above oil layer can be separated and the moisture and impurities can be removed, which is more conducive to the comprehensive utilization of the oil. In addition, the separation method and the method for removing moisture and impurities are well known in the art.

[0043] In some specific examples, the above processing method further includes: subjecting the lower layer to sterilization, detoxification and drying treatment.

[0044] It should be noted that as described above, the separated lower layer can be used as feed after treatment; in addition, before drying, corn husk filler can be added to jointly prepare feed.

[0045] In some specific examples, in the above processing method, the table leftovers are subjected to crushing treatment before heat preservation treatment.

[0046] It should be noted that in the treatment of the present invention, in order to improve the treatment effect of heat preservation, the table leftovers can be first crushed and then heat-preserved. Among them, the method of crushing is well known in the art, and generally a crushing device is used for crushing.

[0047] The embodiment of the present invention also provides an application of the feedstock (viscous substance) layer obtained after being treated by the treatment method in the present invention in the production or preparation of animal feed.

[0048] It should be noted that after being sterilized and disinfected, the feedstock (viscous substance) layer obtained by treating table leftovers through the treatment method of the present invention has no bacteria and viruses, and can be directly used as animal feed to feed animals or 25% of corn husk can be added as a filler, stirred evenly and then dried for use in animal feed.

[0049] After sterilizing and disinfecting the feedstock layer, 25% of corn husk is added as a filler, stirred evenly and then dried as the main raw material of animal feed.

[0050] The embodiment of the present invention also provides an application of the oil layer obtained after being treated by the treatment method in the present invention in the production of biodiesel.

[0051] It should be noted that the oil obtained after treatment in the present invention can be prepared into biodiesel for utilization, increasing the recovery rate of oil in table leftovers.

[0052] To better understand the present invention, the following specific examples are used to further clarify the content of the present invention, but the content of the present invention is not limited to the following examples.

[0053] I. Treatment of table leftovers

[0054] Example 1

[0055] (1) The table leftovers are crushed and then put into a heat-conducting oil electric boiler for heat preservation treatment to obtain a mixture, the temperature is 190 °C, and the treatment time is 2 h;

[0056] (2) The mixture is left to stand for 24 h to obtain an upper layer and a lower layer. The upper layer is an oil layer and the lower layer is a viscous substance.

[0057] Example 2

[0058] (1) The table leftovers are put into a heat-conducting oil electric boiler for heat preservation treatment to obtain a mixture, the temperature is 230 °C, and the treatment time is 1 h 50 min;

[0059] (2) The mixture is left to stand for 24 h to obtain an upper layer and a lower layer. The upper layer is an oil layer and the lower layer is a viscous substance.

[0060] Example 3

[0061] Put the table leftovers into a heat-conducting oil electric boiler for heat preservation treatment to obtain a mixture, with a temperature of 310 °C and a treatment time of 1 h 30 min;

[0062] (2) Let the mixture stand for 24 h to obtain an upper layer and a lower layer. The upper layer is the oil layer and the lower layer is the viscous substance.

[0063] Example 4

[0064] (1) Put the table leftovers into a heat-conducting oil electric boiler for heat preservation treatment to obtain a mixture, with a temperature of 390 °C and a treatment time of 1 h 10 min;

[0065] (2) Let the mixture stand for 24 h to obtain an upper layer and a lower layer. The upper layer is the oil layer and the lower layer is the viscous substance.

[0066] Example 5

[0067] (1) Put the table leftovers into a heat-conducting oil electric boiler for heat preservation treatment to obtain a mixture, with a temperature of 465 °C and a treatment time of 52.5 min;

[0068] (2) Let the mixture stand for 24 h to obtain an upper layer and a lower layer. The upper layer is the oil layer and the lower layer is the viscous substance.

[0069] Example 6

[0070] (1) Put the table leftovers into a heat-conducting oil electric boiler for heat preservation treatment to obtain a mixture, with a temperature of 500 °C, a pressure of 1 Mpa, and a treatment time of 40 min;

[0071] (2) Let the mixture stand for 24 h to obtain an upper layer and a lower layer. The upper layer is the oil layer and the lower layer is the viscous substance.

[0072] Comparative Example 1

[0073] (1) Put the table leftovers into a heat-conducting oil electric boiler for heat preservation treatment to obtain a mixture, with a temperature of 190 °C and a treatment time of 2 h;

[0074] (2) Let the mixture stand for 24 h to obtain an upper layer and a lower layer. The upper layer is the oil layer and the lower layer is the viscous substance.

[0075] Comparative Example 2

[0076] (1) Put the table leftovers into a heat-conducting oil electric boiler for heat preservation treatment to obtain a mixture, with a temperature of 500 °C, a pressure of 1 Mpa, and a treatment time of 40 min;

[0077] (2) Let the mixture stand for 24 h to obtain an upper layer and a lower layer. The upper layer is the oil layer and the lower layer is the viscous substance.

[0078] II. Virus Detection

[0079] The viscous substances prepared in Examples 1 to 6 were subjected to detection for bovine spongiform encephalopathy (BSE) virus to check whether the mixture contained BSE virus. The specific steps were as follows:

[0080] (1) Table leftovers were added to PBS solution at a weight-to-volume ratio of 1:9 (1 g of table leftovers was added to 9 mL of PBS solution) (in 1 L of PBS solution, there were 8 g of NaCl, 0.2 g of KCl, 1.42 g of Na2HPO4, 0.24 g of KH2PO4, and the pH was 7.2 - 7.4). Meanwhile, protease inhibitor ethanol solution (PMSF, phenylmethylsulfonyl fluoride) was added (the volume ratio of protease inhibitor ethanol solution to PBS solution was 1:100) (to prevent degradation of prion proteins).

[0081] (2) After degradation, it was thoroughly ground with a glass homogenizer on ice to obtain a homogenate (to release prion proteins).

[0082] (3) The homogenate was centrifuged at 5000×g for 10 min to obtain a sample to be detected.

[0083] (4) The sample to be detected was qualitatively detected for prions using an ELISA kit (Shanghai Kewenwei Biotechnology Co., Ltd., product number KCW91422) and an enzyme-labeled instrument (BioTek ELx800) (the detection method was carried out according to the kit instructions).

[0084] The detection results of Examples 1 to 6 and Comparative Examples 1 to 2 are shown in Table 1 below.

[0085] Table 1 Detection of BSE virus after treatment in Examples 1 to 6

[0086]

[0087]

[0088] As can be seen from Table 1 above, the detection of BSE virus in the viscous substances obtained after treatment in Examples 1 to 5 was negative. In Comparative Example 1, at a temperature of 110°C and after treatment for 2 h, the removal effect of BSE virus was not good and the detection was positive, indicating that the treatment method in the present invention could not completely kill BSE virus when the temperature was lower than 110°C. Similarly, in Comparative Example 2, when the temperature was raised to 125°C and after treatment for 2 h, the detection result was positive, indicating that Comparative Example 2 also could not completely kill BSE virus in table leftovers.

[0089] As can be known above, under the conditions of a treatment temperature of 190°C to 500°C in the present invention, BSE virus can be killed within 2 h to 40 min.

[0090] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered by the scope of the claims of the present invention.

Claims

1. Method for treating table leftovers, characterized in that Including: Performing heat preservation treatment on table leftovers; wherein, the temperature is 190°C to 500°C, and the pressure is within 1 Mpa.

2. The processing method according to claim 1, wherein Heat preservation treatment. The treatment time is 2 h to 40 min.

3. The processing method according to claim 2, characterized in that The treatment method satisfies any one of the following conditions: When the temperature is 190°C ≤ T ≤ 270°C, the treatment time is 2 h to 1 h 40 min; When the temperature is 270°C < T ≤ 350°C, the treatment time is 1 h 40 min to 1 h 20 min; When the temperature is 350°C < T ≤ 430°C, the treatment time is 1 h 20 min to 1 h; When the temperature is 430°C < T ≤ 500°C, the treatment time is 1 h to 40 min.

4. The processing method according to any one of claims 1 to 3, characterized in that The treatment method further includes: performing heat preservation treatment on table leftovers to obtain a mixture, separating the mixture to obtain an upper layer and a lower layer, and the upper layer is an oil layer.

5. The processing method according to claim 4, wherein The treatment method further includes: separating out the oil layer and removing the moisture and impurities in the oil layer.

6. The processing method according to claim 4, wherein The treatment method further includes: performing sterilization, detoxification and drying treatment on the lower layer.

7. The processing method according to claim 1, 2, 3, 5 or 6, characterized in that, Before performing heat preservation treatment on table leftovers, perform crushing treatment.

8. Application of the lower layer obtained after being treated by the treatment method according to claim 4 or 6 in being used as or preparing animal feed.

9. Application of the oil layer obtained after being treated by the treatment method according to claim 4 or 5 in preparing biodiesel.

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