A method for producing clean energy from kitchen waste and organic waste liquid

Abstract

This application belongs to the field of solid waste treatment technology, specifically relating to a method for preparing clean energy using kitchen waste and organic waste liquid. The method for preparing clean energy using kitchen waste and organic waste liquid includes the following steps: (1) mixing kitchen waste and organic waste liquid for carbonization reaction, and after the reaction is completed, filtering to obtain filtrate and filter cake; (2) drying and gasifying the filter cake in sequence to obtain clean energy. The beneficial effects of this application include: the method for preparing clean energy using kitchen waste and organic waste liquid fully realizes the synergistic resource utilization of kitchen waste and organic waste liquid, and solves the problems of low calorific value, insufficient gasification efficiency and difficult control of pollutant emissions in the process of kitchen waste hydrothermal-gasification alone; the process flow of the method for preparing clean energy using kitchen waste and organic waste liquid is simple, highly operable, and the equipment used is all mature equipment with low technical difficulty and good prospects for industrial application.

Description

Technical Field

[0001] This application belongs to the field of solid waste treatment technology, specifically relating to a method for preparing clean energy using kitchen waste and organic waste liquid. Background Technology

[0002] Kitchen waste is characterized by high moisture content (70%-90%), high organic matter content (80%-90%, dry basis), and high salinity. Traditional incineration technologies are often energy-intensive, require large investments, and are prone to secondary pollution. Hydrothermal gasification technology is an emerging resource-based treatment process. First, hydrothermal carbonization is carried out under medium-temperature and high-pressure conditions (150-250℃, 1.5-5MPa) to convert kitchen waste into high-energy-density hydrothermal coke. Then, through steam gasification at 700-900℃, it is converted into high-quality syngas rich in H2 and CO, achieving the reduction, harmlessness, and energy utilization of kitchen waste.

[0003] However, existing separate hydrothermal gasification processes for kitchen waste still have the following problems: the hydrothermal char heat value is low, and the proportion of syngas in the gasification products is limited, resulting in insufficient energy efficiency; kitchen waste contains high levels of nitrogen, sulfur, and salt, which will release polluting gases such as NH3, H2S, and HCl during the gasification process, affecting the quality of syngas and causing equipment corrosion; if the organic matter and nutrients enriched in the hydrothermal liquid are directly discharged, they will easily cause environmental pollution, and there is still a lack of efficient resource utilization methods.

[0004] Therefore, there is an urgent need to develop an improved process that can enhance the hydrothermal-gasification performance of kitchen waste while achieving high-value utilization of organic matter in the hydrothermal liquid, thereby improving the overall economic efficiency and environmental friendliness of the process. Summary of the Invention

[0005] This application provides a method for preparing clean energy from kitchen waste and organic waste liquid, aiming to solve the problems of low gasification efficiency, poor quality of syngas, and difficulty in controlling pollutant emissions when the existing hydrothermal-gasification process is used to treat kitchen waste.

[0006] This application provides a method for preparing clean energy using kitchen waste and organic waste liquid, including the following steps:

[0007] (1) Mix kitchen waste and organic waste liquid for carbonization reaction. After the reaction is complete, filter to obtain filtrate and filter cake. (2) The filter cake is dried and gasified in sequence to obtain clean energy.

[0008] According to some embodiments of the method for preparing clean energy from kitchen waste and organic waste liquid described in this application, the mass ratio of the kitchen waste to the organic waste liquid is 1:(1-3).

[0009] According to some embodiments of the method for preparing clean energy from kitchen waste and organic waste liquid described in this application, in step (1), the temperature of the carbonization reaction is 150-250°C and the time of the carbonization reaction is 30-50 min.

[0010] According to some embodiments of the method for preparing clean energy from kitchen waste and organic waste liquid described in this application, in step (1), the pressure of the carbonization reaction is 1.5-5 MPa.

[0011] According to some embodiments of the method for preparing clean energy from kitchen waste and organic waste liquid described in this application, in step (1), the pressure of the carbonization reaction is 2-3.5 MPa.

[0012] According to some embodiments of the method for preparing clean energy from kitchen waste and organic waste liquid described in this application, in step (2), the drying temperature is 300-400℃ and the drying time is 1-3h.

[0013] According to some embodiments of the method for preparing clean energy from kitchen waste and organic waste liquid described in this application, in step (2), the temperature of the gasification treatment is 700-900℃ and the time of the gasification treatment is 10-20min.

[0014] According to some embodiments of the method for preparing clean energy from kitchen waste and organic waste liquid described in this application, in step (2), the temperature of the gasification treatment is 800-880℃ and the time of the gasification treatment is 15-18min.

[0015] Some embodiments of the method for preparing clean energy from kitchen waste and organic waste liquid according to this application also include the step of using the residual inorganic minerals after gasification treatment as soil conditioners or fertilizer additives.

[0016] Some embodiments of the method for preparing clean energy from kitchen waste and organic waste liquid according to this application also include using the filtrate obtained in step (1) as liquid fertilizer.

[0017] The beneficial effects of this application include: the method for preparing clean energy using kitchen waste and organic waste liquid described in this application fully realizes the synergistic resource utilization of kitchen waste and organic waste liquid, and solves the problems of low calorific value, insufficient gasification efficiency and difficult control of pollutant emissions in the process of kitchen waste hydrothermal-gasification alone.

[0018] The method for preparing clean energy from kitchen waste and organic waste liquid described in this application has a simple process flow, is easy to operate, uses mature equipment, has low technical difficulty, and has good prospects for industrial application. Detailed Implementation

[0019] The embodiments of the present invention are described in detail below. These embodiments are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0020] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0021] This application provides a method for preparing clean energy using kitchen waste and organic waste liquid, including the following steps: (1) Mix kitchen waste and organic waste liquid for carbonization reaction. After the reaction is complete, filter to obtain filtrate and filter cake. (2) The filter cake is dried and gasified in sequence to obtain clean energy.

[0022] By introducing organic wastewater containing typical components such as sugars, phenols, and carboxylic acids during the carbonization process of kitchen waste, it is possible not only to promote the hydrolysis and condensation of substances such as cellulose and protein in kitchen waste, thereby increasing the energy density and gasification reaction activity of hydrothermal coke, but also to effectively reduce the release of heteroatoms such as nitrogen and sulfur during the gasification stage, thus significantly improving the cleanliness of syngas.

[0023] In some embodiments of this application, the mass ratio of the kitchen waste to the organic waste liquid is 1:(1-3); for example, 1:1, 1:2, 1:3, etc. The sugars, phenols and organic acids contained in the organic waste water participate in the reaction, further promoting the formation of the carbon skeleton and improving the energy density and structural stability of the resulting hydrothermal coke.

[0024] In some embodiments of this application, in step (1), the temperature of the carbonization reaction is 150-250℃, such as 150℃, 180℃, 200℃, 210℃, 226℃, 230℃, 250℃, etc., and the time of the carbonization reaction is 30-50min; such as 30min, 35min, 38min, 43min, 50min, etc. During this process, the organic matter in the kitchen waste undergoes hydrolysis, condensation and aromatization reactions under high temperature and high pressure water environment, while the sugars, phenols and organic acids contained in the organic wastewater participate in the reaction, further promoting the formation of the carbon skeleton and improving the energy density and structural stability of the obtained hydrothermal coke.

[0025] In some embodiments of this application, in step (1), the pressure of the carbonization reaction is 1.5-5 MPa, for example 1.5 MPa, 2 MPa, 2.3 MPa, 2.6 MPa, 3.3 MPa, 3.7 MPa, 4.1 MPa, 5 MPa, etc. As a preferred embodiment, the pressure of the carbonization reaction is 2-3.5 MPa.

[0026] In some embodiments of this application, in step (2), the drying temperature is 300-400℃, such as 300℃, 320℃, 350℃, 380℃, 400℃, etc., and the drying time is 1-3h; such as 1h, 2h, 3h, etc.

[0027] In some embodiments of this application, in step (2), the temperature of the gasification treatment is 700-900℃, for example, 700℃, 750℃, 800℃, 850℃, 900℃, etc., and the time of the gasification treatment is 10-20min, for example, 10min, 12min, 15min, 18min, 20min, etc. During the gasification treatment stage, under the action of steam, the hydrothermal coke undergoes an oxidation reaction, a water-gas reaction, and a Boudouard reaction to generate syngas mainly composed of hydrogen and carbon monoxide. The obtained syngas can be used as clean fuel or chemical raw material after purification. As a preferred embodiment, in step (2), the temperature of the gasification treatment is 800-880℃, and the time of the gasification treatment is 15-18min.

[0028] In some embodiments of this application, the method further includes the step of using the residual inorganic minerals after gasification as a soil conditioner or fertilizer additive.

[0029] In some embodiments of this application, the filtrate obtained in step (1) is also used as liquid fertilizer. The filtrate is rich in nutrients such as ammonia nitrogen and phosphate, and its use as liquid waste realizes the resource utilization of by-products.

[0030] The method for producing clean energy from kitchen waste and organic waste liquid described in this application achieves the synergistic recycling of hydrothermal fluid and organic waste liquid, reducing the consumption of external water sources, avoiding direct discharge of hydrothermal waste liquid, lowering treatment costs, and improving the overall energy efficiency of the system. The final process can produce high calorific value (15-20 MJ / Nm³) energy. 3 Hydrogen-rich syngas can be used for clean energy or chemical synthesis; the by-product hydrothermal fluid is rich in ammonia nitrogen and soluble phosphorus, which can be further developed into liquid fertilizer, increasing the economic efficiency and added value of the process.

[0031] The method for preparing clean energy from kitchen waste and organic waste liquid described in this application has significant advantages in energy utilization, pollutant control, and high-value utilization of by-products, and can greatly promote the application of kitchen waste hydrothermal-gasification co-processing technology.

[0032] The technical solution of this application will be further explained below with reference to the embodiments.

[0033] Example 1 A method for producing clean energy from kitchen waste and organic waste liquid includes the following steps: (1) Mix kitchen waste and organic waste liquid in a mass ratio of 1:2 and carbonize them for 30 minutes at a temperature of 150℃ and a pressure of 3MPa. After the reaction is complete, the reaction products are transported to a mud-water separator for filtration to obtain hydrothermal liquid and coke cake. The hydrothermal liquid is rich in nutrients such as ammonia nitrogen and phosphate, which can be further developed into liquid fertilizer. (2) The coke cake is transported to the gasifier. The working temperature of the drying zone of the gasifier is set to 350℃. The coke cake is dried for 80 minutes. The temperature of the gasification reaction layer of the gasifier is set to 700℃. The gasification process is carried out for 15 minutes to obtain clean energy mainly composed of H2 and CO. The ash residue after gasification is discharged from the bottom of the gasifier and can be used as a soil conditioner or fertilizer additive.

[0034] Example 2 The method for preparing clean energy from kitchen waste and organic waste liquid described in Example 2 differs from that in Example 1 only in that the carbonization temperature during the preparation of clean energy from kitchen waste and organic waste liquid in Example 2 is 200°C.

[0035] The specific operating steps include: (1) Mix kitchen waste and organic waste liquid in a mass ratio of 1:2 and carbonize them for 30 minutes at a temperature of 200℃ and a pressure of 3MPa. After the reaction is completed, the reaction products are transported to a mud-water separator for filtration to obtain hydrothermal liquid and coke cake. The hydrothermal liquid is rich in nutrients such as ammonia nitrogen and phosphate, which can be further developed into liquid fertilizer. (2) The coke cake is transported to the gasifier. The working temperature of the drying zone of the gasifier is set to 350℃. The coke cake is dried for 80 minutes. The temperature of the gasification reaction layer of the gasifier is set to 700℃. The gasification process is carried out for 15 minutes to obtain clean energy mainly composed of H2 and CO. The ash residue after gasification is discharged from the bottom of the gasifier and can be used as a soil conditioner or fertilizer additive.

[0036] Example 3 The method for preparing clean energy from kitchen waste and organic waste liquid described in Example 3 differs from that in Example 1 only in that the carbonization temperature during the preparation of clean energy from kitchen waste and organic waste liquid in Example 3 is 250°C.

[0037] The specific operating steps include: (1) Mix kitchen waste and organic waste liquid in a mass ratio of 1:2 and carbonize them for 30 minutes at a temperature of 250℃ and a pressure of 3MPa. After the reaction is completed, the reaction products are sent to a mud-water separator for filtration to obtain hydrothermal liquid and coke cake. The hydrothermal liquid is rich in nutrients such as ammonia nitrogen and phosphate, which can be further developed into liquid fertilizer. (2) The coke cake is transported to the gasifier. The working temperature of the drying zone of the gasifier is set to 350℃. The coke cake is dried for 80 minutes. The temperature of the gasification reaction layer of the gasifier is set to 700℃. The gasification process is carried out for 15 minutes to obtain clean energy mainly composed of H2 and CO. The ash residue after gasification is discharged from the bottom of the gasifier and can be used as a soil conditioner or fertilizer additive.

[0038] Example 4 The method for preparing clean energy from kitchen waste and organic waste liquid described in Example 4 differs from that in Example 1 only in that the gasification temperature during the preparation of clean energy from kitchen waste and organic waste liquid in Example 4 is 800°C.

[0039] The specific operating steps include: (1) Mix kitchen waste and organic waste liquid in a mass ratio of 1:2 and carbonize them for 30 minutes at a temperature of 150℃ and a pressure of 3MPa. After the reaction is complete, the reaction products are transported to a mud-water separator for filtration to obtain hydrothermal liquid and coke cake. The hydrothermal liquid is rich in nutrients such as ammonia nitrogen and phosphate, which can be further developed into liquid fertilizer. (2) The coke cake is transported to the gasifier. The working temperature of the drying zone of the gasifier is set to 350℃. The coke cake is dried for 80 minutes. The temperature of the gasification reaction layer of the gasifier is set to 800℃. The gasification process is carried out for 15 minutes to obtain clean energy mainly composed of H2 and CO. The ash residue after gasification is discharged from the bottom of the gasifier and can be used as a soil conditioner or fertilizer additive.

[0040] Example 5 The method for preparing clean energy from kitchen waste and organic waste liquid described in Example 5 differs from that in Example 1 only in that the gasification temperature during the preparation of clean energy from kitchen waste and organic waste liquid in Example 5 is 900°C.

[0041] The specific operating steps include: (1) Mix kitchen waste and organic waste liquid in a mass ratio of 1:2 and carbonize them for 30 minutes at a temperature of 150℃ and a pressure of 3MPa. After the reaction is complete, the reaction products are transported to a mud-water separator for filtration to obtain hydrothermal liquid and coke cake. The hydrothermal liquid is rich in nutrients such as ammonia nitrogen and phosphate, which can be further developed into liquid fertilizer. (2) The coke cake is transported to the gasifier. The working temperature of the drying zone of the gasifier is set to 350℃. The coke cake is dried for 80 minutes. The temperature of the gasification reaction layer of the gasifier is set to 900℃. The gasification process is carried out for 15 minutes to obtain clean energy mainly composed of H2 and CO. The ash residue after gasification is discharged from the bottom of the gasifier and can be used as a soil conditioner or fertilizer additive.

[0042] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A method for preparing clean energy using kitchen waste and organic waste liquid, characterized in that, Includes the following steps: (1) Mix kitchen waste and organic waste liquid for carbonization reaction. After the reaction is complete, filter to obtain filtrate and filter cake. (2) The filter cake is dried and gasified in sequence to obtain clean energy.

2. The method for preparing clean energy from kitchen waste and organic waste liquid according to claim 1, characterized in that, The mass ratio of the kitchen waste to the organic waste liquid is 1:(1-3).

3. The method for preparing clean energy from kitchen waste and organic waste liquid according to claim 1, characterized in that, In step (1), the carbonization reaction temperature is 150-250℃ and the carbonization reaction time is 30-50min.

4. The method for preparing clean energy from kitchen waste and organic waste liquid according to claim 1, characterized in that, In step (1), the pressure of the carbonization reaction is 1.5-5 MPa.

5. The method for preparing clean energy from kitchen waste and organic waste liquid according to claim 1, characterized in that, In step (1), the pressure of the carbonization reaction is 2-3.5 MPa.

6. The method for preparing clean energy from kitchen waste and organic waste liquid according to claim 1, characterized in that, In step (2), the drying temperature is 300-400℃ and the drying time is 1-3h.

7. The method for preparing clean energy from kitchen waste and organic waste liquid according to claim 1, characterized in that, In step (2), the temperature of the gasification treatment is 700-900℃ and the time of the gasification treatment is 10-20min.

8. The method for preparing clean energy from kitchen waste and organic waste liquid according to claim 1, characterized in that, In step (2), the temperature of the gasification treatment is 800-880℃ and the time of the gasification treatment is 15-18min.

9. The method for preparing clean energy from kitchen waste and organic waste liquid according to claim 1, characterized in that, It also includes the step of using the residual inorganic minerals after gasification as soil conditioners or fertilizer additives.

10. The method for preparing clean energy from kitchen waste and organic waste liquid according to claim 1, characterized in that, It also includes using the filtrate obtained in step (1) as liquid fertilizer.