Method for rapidly treating organic solid waste

Abstract

The invention discloses a method for rapidly treating organic solid waste. The method comprises the following step: stirring organic solid waste raw materials at the temperature of 10-100 DEG C and the pressure of 0-101 Kpa for 0-80 minutes. The method is simple, a negative pressure heating treatment mode is adopted, the boiling point of water is reduced under negative pressure, low-temperature boiling is achieved, part of water is taken away, eggs and pathogens can be rapidly and effectively killed, and organic solid waste biomass resources such as biomass straw and / or livestock manure can be rapidly treated.

Description

Technical Field

[0001] The present invention belongs to the technical field of organic solid waste treatment, and particularly relates to a method for rapidly treating organic solid waste. Background Art

[0002] China is an important producer of grain and meat. During the production process, a large amount of straw and livestock manure are generated. They contain a large amount of organic matter and inorganic elements and are very important and high-quality biomass resources. Due to the influence of various factors such as national and even global environmental protection, straw burning bans, pesticide or / and antibiotic residues, and pathogen carriers, only a small amount of these high-quality biomass resources are subjected to resource treatment such as compost fermentation, and most of them are not fully utilized. For the large-scale application of these biomass resources, the rapid treatment technology of biomass resources is a crucial link.

[0003] The expansion of the scale of animal husbandry has made the treatment of livestock manure increasingly difficult. Since livestock manure contains a large amount of pathogens, harmful eggs, antibiotics, etc., in order to eliminate the influence of these factors, existing methods use various ways such as composting, anaerobic fermentation, aerobic fermentation, and biogas production for treatment, and then return them to the fields for application. Although these methods are very effective, they have problems such as long fermentation cycles, large floor areas, low mechanization levels, strong odors, and even longer treatment cycles in winter. This makes livestock manure and / or biomass straw important non-point source pollutants in residents' lives, and biomass solid waste resources are not fully utilized, seriously wasting biomass organic resources.

[0004] For the treatment method of crop straw, except for a small part used as animal feed, generally, it is directly returned to the field after rotary tillage in the large field. Although it can save a large amount of labor and supplement organic matter and nutrients, it also provides an opportunity for some pathogens or harmful eggs to survive the cold winter, resulting in an increase in the incidence of crop diseases and pests in the following year, and thus more pesticides are applied.

[0005] Adopting the negative pressure technology has the characteristics of good effect and fast speed in dealing with livestock and poultry manure, kitchen waste, biomass straw, etc. Therefore, there have been many patents on using negative pressure to treat organic matter. In the invention patent of Biomass Negative Pressure Degradation Pretreatment Process (CN103316891A), it is disclosed that under negative pressure conditions, the temperature is raised to 70 - 150 °C. At this time, the water is completely vaporized, the pressure is 0.4 MPa, and then it suddenly explodes under negative pressure conditions to complete the process. In this process, the production process temperature is relatively high, the specific heat capacity of water is very large, water vaporizes, and the energy consumption is too high; the blasting pressure difference is 0.4 - (-0.1) = 0.5 MPa, the pressure is relatively high, the equipment pressure-bearing requirement is high, and the manufacturing cost is high; and when the temperature rises to 150 °C, there is a problem of contradiction in how to achieve the change between positive and negative pressures (from 0.4 MPa to 0.0 MPa). In the invention patent of Biomass Negative Pressure Degradation Pretreatment Device (CN 103316890 B), its equipment structure is relatively complex, the equipment manufacturing cost is high, and it is not conducive to the large-scale production of biomass treatment. In the invention patent of the process and system for preparing organic fertilizer from livestock and poultry manure (publication number CN104557158A), its process requires solid-liquid separation first. This treatment process will produce a large amount of sewage that cannot be treated in time, and there is still serious non-point source pollution. And it uses the conditions of a temperature of 140.0 - 160.0 °C, a pressure of 8.0 - 10.0 MPa, and finally reduces to a vacuum degree of -0.1 MPa to treat livestock and poultry manure. This solution has a relatively high production process temperature and high energy consumption; the pressure is high, the equipment pressure-bearing is too large, and the equipment manufacturing cost is high. During the process, the operating pressure drops from 10.1 MPa to 0.0 MPa. Compared with directly using a high-pressure device with a pressure drop of 100.0 MPa from 10.1 MPa to 0.0 MPa, it only differs by 1%. As a result, the manufacturing cost of this equipment will increase exponentially. At the same time, a set of negative pressure equipment is also required, and there is still a certain gap between the obtained product and meeting the standards of organic fertilizer.

[0006] In the invention patents for treating livestock and poultry manure by negative pressure, two invention patents, namely, a segmented continuous deep dehydration treatment process for livestock and poultry manure (CN110698030A) and an integrated system for two-stage continuous deep dehydration treatment of livestock and poultry manure (CN109836028A), their main purpose is to dry and dehydrate livestock and poultry manure, but insufficient attention is paid to other indicators that make the livestock and poultry manure convenient as an organic fertilizer base material. For the utility model patent, a pollution-free vacuum thermal drying device for livestock and poultry manure (CN206089411U), the main purpose is to focus on drying, providing a conventional idea on how to treat livestock and poultry manure, and there are no corresponding data on other indicators of the product quality obtained from livestock and poultry manure, operating conditions, methods, etc. For the utility model patent, a corn straw fermentation device (CN209508239U), it also focuses on the structural principle of the device, without corresponding accurate basic data and actual operations. For the invention patent, a treatment method for pig manure (CN109650956A), on the one hand, this invention patent requires a concrete manure collection pool, resulting in a large floor area. The main purpose of this technology is mainly for the concentration of organic solid waste, while ignoring the factor that livestock and poultry manure has a large water content. At the same time, this patent requires vaporizing 3000 - 600 = 2400 (kg) of water per day, that is, 2.4 tons of water. According to the new water coefficient of 0.0857 kgce / t, to vaporize 1 ton of water, 0.857 tons of standard coal is required, that is, 2.06 tons of standard coal is consumed per day. The equivalent natural gas or electricity cost is an extremely large figure. Given that the specific heat capacity of water is very large and the energy consumption is too high, this method is not practical. At the same time, the scale of a 1000-head farm is very small and not suitable for the large-scale treatment of livestock and poultry manure in large farms. Therefore, a method for quickly treating organic solid waste is needed. Summary of the Invention

[0007] The purpose of the present invention is to provide a method for quickly treating organic solid waste that overcomes the defects of the large-scale utilization of current organic solid waste biomass resources.

[0008] To achieve the above purpose, the present invention adopts the following technical solutions:

[0009] A method for quickly treating organic solid waste, comprising the following steps: Stir the organic solid waste raw material at 10 - 100 °C and a pressure of 0 - 101 Kpa for 0 - 80 min.

[0010] Preferably, the organic solid waste is one or several of livestock and poultry manure, kitchen waste, or straw.

[0011] Preferably, the organic solid waste is livestock and poultry manure or a mixture of livestock and poultry manure and straw. The straw is crushed straw, soaked or wetted with water for 30 min, and added to the livestock and poultry manure to adjust the water content;

[0012] In order to improve the treatment effect and efficiency of organic solid waste, the moisture content of the organic solid waste is less than 80%.

[0013] Preferably, the moisture content of the organic solid waste is 55 - 65%. At this moisture content, the treatment effect is the best. Further, the moisture content of the organic solid waste is 60%.

[0014] Preferably, the stirring speed is 0 - 350 revolutions per minute.

[0015] The stirring speed is 100 - 200 revolutions per minute.

[0016] In order to treat the steam generated during the treatment process, it also includes condensing the steam generated during the treatment. The waste heat obtained by condensation can be used as the heat source for preheating the organic solid waste biomass resources, reducing energy consumption; when condensing, the components of the gas during the treatment process can also be collected. The gas components mainly contain elements such as N, S, and P. After collection and treatment, they can be used as supplementary materials for trace elements in the base material.

[0017] Preferably, fully considering the manufacturing cost of the equipment, the pressure is 4 - 60 Kpa.

[0018] Preferably, the treatment time is 40 - 80 minutes.

[0019] Preferably, in order to achieve better effects of sterilization and killing of insect eggs, the temperature is 30 - 85 °C.

[0020] The method of the present invention is simple. It uses the method of negative pressure heating to treat organic solid waste. Under negative pressure, the boiling point of water decreases, realizing low-temperature boiling, removing part of the moisture, and being able to quickly and effectively kill insect eggs and pathogens to ensure the safety and hygiene of the treated product, and to retain the effective substances in the organic solid waste to the greatest extent, accelerating the utilization of organic solid waste biomass resources such as biomass straw and / or livestock and poultry manure.

[0021] The method of the present invention is easy to operate, has a relatively low temperature during the production process, low energy consumption, and low pressure resistance. There is only 1 atmospheric pressure, the equipment cost is low, and the treatment process time is short. Organic solid waste can be treated under certain conditions such as pressure and temperature, which can cause the chemical bonds in the organic solid waste to be torn. Especially after livestock and poultry manure is treated by various digestive enzymes produced by the animal's abdominal digestive system, it is easier to obtain the base material of organic fertilizer.

[0022] The supporting equipment related to the present invention has low requirements. According to different production scales, equipment with a capacity of 0.5 - 10.0 tons can be selected. It has a high degree of mechanization, low labor costs, and a small floor area, making it suitable for the treatment of manure and sewage in large, medium, and small-sized breeding enterprises. The products obtained by the method of the present invention can be used as the basic raw material and / or substrate of biological organic fertilizers, further improving the soil, increasing soil organic matter, reducing the occurrence of pests and diseases, and reducing the amount of pesticides used while increasing their efficacy.

[0023] This experiment Detailed implementation manners

[0024] The following further illustrates the present invention in conjunction with embodiments, but the protection scope of the present invention is not limited thereto.

[0025] Embodiment 1

[0026] A method for quickly treating organic solid waste, comprising the following steps: Stir and process the organic solid waste raw material at a temperature of 82 °C and a pressure of 50.70 Kpa for 75 min; the stirring speed is 170 revolutions / min;

[0027] The organic solid waste raw material is chicken manure with a moisture content of 60%.

[0028] Embodiment 2

[0029] A method for quickly treating organic solid waste, comprising the following steps: Stir and process the organic solid waste raw material at a temperature of 78 °C and a pressure of 40.5 Kpa for 65 min; the stirring speed is 170 revolutions / min;

[0030] The organic solid waste raw material is a mixture of chicken manure and straw, and the mass ratio of chicken manure to straw is 7:3, with a moisture content of 55%; the straw is crushed corn straw and soaked in water for 30 min.

[0031] Embodiment 3

[0032] A method for quickly treating organic solid waste, comprising the following steps: Stir and process the organic solid waste raw material at a temperature of 70 °C and a pressure of 30.4 Kpa for 59 min; the stirring speed is 160 revolutions / min;

[0033] The organic solid waste raw material is pig manure with a moisture content of 65%.

[0034] Embodiment 4

[0035] A method for quickly treating organic solid waste, comprising the following steps: Stir and process the organic solid waste raw material at a temperature of 61 °C and a pressure of 20.3 Kpa for 55 min; the stirring speed is 160 revolutions / min;

[0036] The organic solid waste raw material is a mixture of chicken manure and straw. The mass ratio of chicken manure to straw is 7:3, and the water content is 58%. The straw is crushed corn straw and soaked in water for 30 minutes.

[0037] Example 5

[0038] A method for quickly treating organic solid waste includes the following steps: Stir the organic solid waste raw material at a temperature of 48 °C and a pressure of 10.1 Kpa for 50 minutes; The stirring speed is 120 revolutions per minute;

[0039] The organic solid waste raw material is a mixture of pig manure and straw. The mass ratio of pig manure to straw is 3:2, and the water content is 62%. The straw is crushed corn straw and soaked in water for 30 minutes.

[0040] Example 6

[0041] A method for quickly treating organic solid waste includes the following steps: Stir the organic solid waste raw material at a temperature of 33 °C and a pressure of 5.1 Kpa for 46 minutes; The stirring speed is 130 revolutions per minute;

[0042] The organic solid waste raw material is chicken manure, and the water content is 61%.

[0043] Example 7

[0044] A method for quickly treating organic solid waste includes the following steps: Stir the organic solid waste raw material at a temperature of 45 °C and a pressure of 1.0 Kpa for 43 minutes; The stirring speed is 170 revolutions per minute;

[0045] The organic solid waste raw material is cow dung, and the water content is 57%.

[0046] Example 8

[0047] A method for quickly treating organic solid waste includes the following steps: Stir the organic solid waste raw material at a temperature of 50 °C and a pressure of 1.0 Kpa for 40 minutes; The stirring speed is 130 revolutions per minute;

[0048] The organic solid waste raw material is chicken manure, and the water content is 48%.

[0049] Example 9

[0050] A method for quickly treating organic solid waste includes the following steps: Stir the organic solid waste raw material at a temperature of 60 °C and a pressure of 0.5 Kpa for 35 minutes; The stirring speed is 210 revolutions per minute;

[0051] The organic solid waste raw material is crushed corn straw, wetted with water for 30 minutes, and the water content is 50%.

[0052] Example 10

[0053] A method for quickly treating organic solid waste, comprising the following steps: stirring the organic solid waste raw material at a temperature of 85 °C and a pressure of 101 Kpa for 80 min; the stirring speed is 150 revolutions / min;

[0054] The organic solid waste raw material is kitchen waste with a moisture content of 55%.

[0055] Example 11

[0056] A method for quickly treating organic solid waste, comprising the following steps: stirring the organic solid waste raw material at a temperature of 70 °C and a pressure of 0.3 Kpa for 30 min; the stirring speed is 150 revolutions / min;

[0057] The organic solid waste raw material is chicken manure with a moisture content of 45%.

[0058] Example 12

[0059] A method for quickly treating organic solid waste, comprising the following steps: stirring the organic solid waste raw material at a temperature of 85 °C and a pressure of 0.1 Kpa for 25 min; the stirring speed is 160 revolutions / min;

[0060] The organic solid waste raw material is chicken manure and straw, and the mass ratio of chicken manure to straw is 7:2, with a moisture content of 40%. The designed straw is crushed corn straw and is wetted with water for 30 min.

[0061] The chicken manure products and the chicken manure-straw mixed products obtained in Examples 11 and 12 are tested, and the specific results are shown in Table 1 and Table 2 below.

[0062] Table 1 Detection results of the treated chicken manure products in Example 11

[0063] Measurement indicators Related requirements Measured value 1 Measured value 2 Measured value 3 Average value Organic carbon (%) ≥30％ 39.17 39.69 37.79 38.88 Total nutrients (N + P + K) % ≥4.0％ 4.82 4.82 4.83 4.82 Soil pH 5.5-8.5 6.75 6.70 6.83 6.76 Seed germination index (GI) % ≥70％ 90.00 95.06 92.32 93.74 Mass fraction of mechanical impurities % ≤0.5 0.37 0.41 0.42 0.40 Fecal coliform count (MNP / g) ≤100 90.00 88.00 92.00 90 Mortality rate of Ascaris eggs (%) ≥95％ 100.00 100.00 100.00 100.00 Total nitrogen (%) --- 2.68 2.59 2.65 2.64 Total phosphorus (%) --- 1.12 1.22 1.22 1.19 Total potassium (%) --- 1.03 1.00 0.96 1.00 Available nitrogen (mg / kg) --- 2290.26 2469.60 2501.94 2421 Dissolved total nitrogen DTN (mg / kg) --- 981.65 1019.26 929.56 976.82 Dissolved organic carbon DOC % --- 2.44 2.32 2.41 2.39 Lignin content (%) --- 18.00 22.98 19.09 20.02

[0064] Table 2 Detection results of the treated chicken manure and straw mixed products in Example 12

[0065]

[0066]

[0067] According to the results of Table 1 and Table 2, it can be seen that the method of the present invention can quickly and effectively kill eggs and pathogens, ensuring the safety of treating organic solid waste. In addition, the method of the present invention has a short treatment time and a low temperature, enabling efficient treatment of organic solid waste. During the treatment, due to the low temperature and low pressure, the effective nutrients in the organic solid waste can be guaranteed to the greatest extent. The product obtained by treating the organic solid waste biomass resources can be used as the basic raw material or base material of bio-organic fertilizer, realizing the rapid treatment of organic solid waste, improving the effective utilization rate of organic solid waste, reducing the negative impact on the environment, and at the same time reducing the environmental pollution problems brought by the traditional treatment methods of these resources.

[0068] It should be noted that in this article, relational terms such as "one" and "two" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation. An element defined by the statement "comprising one..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the element.

[0069] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for rapidly treating organic solid waste, characterized in that: The method comprises the following steps: stirring the organic solid waste raw material at a temperature of 10-100° C. and a pressure of 0-101 KPa for 0-80 minutes.

2. A method for rapidly treating organic solid waste according to claim 1, characterized in that: The organic solid waste is one or more of poultry and livestock manure, kitchen waste or straw.

3. The method for rapidly treating organic solid waste according to claim 1, characterized in that: The moisture content of the organic solid waste is less than 80%.

4. A method for rapidly treating organic solid waste according to claim 3, characterized in that: The moisture content of the organic solid waste is 30-80%.

5. The method for rapidly treating organic solid waste according to claim 1, characterized in that: The stirring speed is 0-350 rpm.

6. The method for rapidly treating organic solid waste according to claim 1, characterized in that: It also includes condensing the steam generated during the process.

7. The method for rapidly treating organic solid waste according to claim 5, characterized in that: The stirring speed is 100-200 rpm.

8. The method for rapidly treating organic solid waste according to claim 1, characterized in that: The pressure is 4-60Kpa.

9. The method for rapidly treating organic solid waste according to claim 1, characterized in that: The processing time is 40-80 minutes.

10. The method for rapidly treating organic solid waste according to claim 1, characterized in that: The temperature is 30-85°C.

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