A pretreatment method for black and odorous sludge

Abstract

The application discloses a pretreatment method for black and odorous sludge, and belongs to the technical field of sludge treatment. The method comprises the following steps: removing biological components of the black and odorous sludge by using high-temperature and ultraviolet technologies, eliminating harmful organisms and odors, and obtaining primary treatment sludge; further treating the primary treatment sludge by biological degradation and chemical oxidation, removing organic substances in the primary treatment sludge, obtaining secondary treatment sludge, and reducing the content of organic substances; removing inorganic substances in the secondary treatment sludge by adopting means such as precipitation, filtration and adsorption, purifying the sludge, and obtaining tertiary treatment sludge; and performing standard detection on the tertiary treatment sludge, and ensuring that the quality meets relevant requirements. The pretreatment method can effectively remove biological components, organic substances and inorganic substances in the black and odorous sludge, reduce the content of heavy metals and biological toxicity, and can lay a foundation for subsequent sludge resource utilization or safe disposal.

Description

Technical Field

[0001] This invention relates to the field of sludge treatment technology, specifically a pretreatment method for black and odorous sludge. Background Technology

[0002] Black and odorous sludge is a sediment rich in organic matter and pollutants, which is usually accumulated in sewage treatment plants, rivers and lakes. With proper treatment and resource utilization, it can be transformed into a valuable resource.

[0003] By pretreating black and odorous sludge, it can be transformed into a variety of valuable resources, which can be widely used in agriculture, landscaping, building materials, energy production and ecological restoration, achieving the dual goals of resource utilization and environmental protection.

[0004] Therefore, there is an urgent need to develop a pretreatment method for black and odorous sludge. Summary of the Invention

[0005] To address the shortcomings of the existing technology, the present invention aims to provide a pretreatment method for black and odorous sludge. This pretreatment method, through the comprehensive application of physical, chemical, and biological technologies, efficiently and environmentally improves the properties of black and odorous sludge, laying the foundation for subsequent resource utilization and environmental remediation.

[0006] The technical solution adopted by this invention to solve its technical problem is as follows:

[0007] A pretreatment method for black and odorous sludge is provided, comprising the following steps:

[0008] High temperature and ultraviolet light are used to remove biological components from black and odorous sludge, resulting in primary treated sludge.

[0009] Organic matter is removed from primary treated sludge using biodegradation and chemical oxidation to obtain secondary treated sludge.

[0010] The inorganic matter in the secondary treated sludge is removed by sedimentation, filtration and adsorption to obtain tertiary treated sludge.

[0011] Standard tests were conducted on the sludge from the three treatments, and the results were used to determine whether the pretreatment of the black and odorous sludge had been completed.

[0012] Preferably, the biological components of black and odorous sludge are removed using high temperature and ultraviolet light, resulting in a sludge treatment process that includes:

[0013] The black and smelly sludge is heated and simultaneously irradiated with ultraviolet light;

[0014] The heating temperature is determined based on the mass, volume, and initial moisture content of the black and odorous sludge. The calculation formula is as follows:

[0015] Heating temperature = (mass of black and smelly sludge * initial moisture content) / (volume * coefficient A) + reference temperature;

[0016] Wherein, coefficient A is an empirical value; and the reference temperature is the set minimum value.

[0017] Preferably, the biological components of black and odorous sludge are removed using high temperature and ultraviolet light, resulting in a sludge treatment process that includes:

[0018] The ultraviolet radiation intensity is determined based on the mass, volume, and initial organic composition ratio of the black and odorous sludge. The calculation formula is as follows:

[0019] UV intensity = (mass of black and odorous sludge * initial organic component ratio) / (volume * coefficient B) + reference intensity;

[0020] Wherein, coefficient B is an empirical value; and the benchmark strength is the set minimum strength.

[0021] Preferably, when using biodegradation and chemical oxidation to remove organic matter from primary treated sludge to obtain secondary treated sludge, the process includes:

[0022] The biodegradation involves adding microbial agents to the primary treated sludge to decompose the organic matter in the primary treated sludge.

[0023] The microbial agent includes nitrifying bacteria and auxiliary bacteria, wherein the auxiliary bacteria are thermophilic lipophilic bacilli.

[0024] Preferably, when using biodegradation and chemical oxidation to remove organic matter from primary treated sludge to obtain secondary treated sludge, the method further includes:

[0025] After the primary treated sludge undergoes biodegradation, it is then chemically oxidized.

[0026] The oxidants used in chemical oxidation are hydrogen peroxide and sodium hypochlorite.

[0027] Preferably, when performing chemical oxidation, it includes:

[0028] Hydrogen peroxide is evenly sprayed onto the sludge after the primary treatment of biodegradation to carry out the oxidation reaction.

[0029] Then, sodium hypochlorite solution is added to the sludge to carry out an oxidation reaction.

[0030] Preferably, the concentration of hydrogen peroxide is 30%-50%, and the mass ratio of hydrogen peroxide to the primary treated sludge is (0.01-0.05):1;

[0031] The concentration of the sodium hypochlorite solution is 1%-3%, and the mass ratio of the sodium hypochlorite solution to the primary treated sludge is (0.005-0.015):1.

[0032] Preferably, when using sedimentation, filtration, and adsorption to remove inorganic matter from secondary treated sludge to obtain tertiary treated sludge, the process includes:

[0033] The sludge from the secondary treatment process is allowed to settle naturally before being filtered.

[0034] After filtration, an adsorbent is used to adsorb the secondary treated sludge.

[0035] Preferably, the method for preparing the adsorbent includes:

[0036] After mixing activated carbon and bentonite, the mixture is ground and sieved to obtain a mixture; wherein the ratio of activated carbon to bentonite is 1:(2-3).

[0037] The mixture is activated at 800-1000℃ for 2-4 hours.

[0038] After activation, the adsorbent is cooled to obtain the adsorbent.

[0039] More preferably, the particle size of the mixture is 0.1-0.5 mm.

[0040] Preferably, when performing standard tests on the sludge from the three treatments and determining whether the pretreatment of black and odorous sludge has been completed based on the test results, the following steps are included:

[0041] The sludge from the three treatments was tested for indicators, including organic matter content, inorganic matter content, heavy metal content, and biotoxicity.

[0042] The detected index data are compared and analyzed with the preset preprocessing standards;

[0043] When the comparison results show that all indicators of the three treated sludge samples meet the pretreatment standards, the pretreatment of the black and odorous sludge is deemed complete.

[0044] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0045] 1. The pretreatment method for black and odorous sludge exemplified by the present invention has the advantages of high treatment efficiency, low cost, and stable and reliable treatment effect. By precisely controlling the heating temperature and ultraviolet intensity, it can achieve rapid and effective removal of biological components in black and odorous sludge. This not only improves the treatment efficiency, but also reduces the consumption of energy and resources, and has broad application prospects and market demand.

[0046] 2. The pretreatment method for black and odorous sludge exemplified in this invention, in the organic matter removal stage, employs a combination of biodegradation and chemical oxidation, which can more comprehensively remove organic matter from the sludge. In particular, the nitrifying bacteria and auxiliary bacteria (thermophilic steatobacterium) in the added microbial agent can work synergistically under different environmental conditions to achieve better removal results. Simultaneously, the hydrogen peroxide and sodium hypochlorite used in the chemical oxidation stage not only have highly efficient oxidizing capabilities but also exhibit mild reaction conditions and low equipment requirements, further reducing treatment costs.

[0047] 3. The pretreatment method for black and odorous sludge exemplified in this invention, in the inorganic matter removal stage, employs a combined process of sedimentation, filtration, and adsorption, which effectively removes inorganic substances from the sludge. In particular, the prepared adsorbent exhibits excellent adsorption performance, enabling highly efficient removal of inorganic substances. Furthermore, the preparation method of this adsorbent is simple, low-cost, and easy to mass-produce.

[0048] 4. The pretreatment method for black and odorous sludge exemplified in this invention uses standard testing to determine whether the pretreatment of the black and odorous sludge is complete, ensuring the stability and reliability of the treatment effect. By testing indicators such as organic matter content, inorganic matter content, heavy metal content, and biotoxicity, and comparing them with preset pretreatment standards, it can be ensured that the treated sludge achieves the expected treatment effect and meets the requirements for subsequent utilization or disposal. Detailed Implementation

[0049] Exemplary embodiments of this disclosure will now be described in more detail. While exemplary embodiments of this disclosure are shown below, it should be understood that this disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of this disclosure and to fully convey its scope to those skilled in the art. It should be noted that, unless otherwise specified, embodiments and features described herein can be combined with each other. The invention will now be described in detail with reference to embodiments.

[0050] Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] This embodiment proposes a pretreatment method for black and odorous sludge, comprising the following steps:

[0052] High temperature and ultraviolet light are used to remove biological components from black and odorous sludge, resulting in primary treated sludge.

[0053] Organic matter is removed from primary treated sludge using biodegradation and chemical oxidation to obtain secondary treated sludge.

[0054] The inorganic matter in the secondary treated sludge is removed by sedimentation, filtration and adsorption to obtain tertiary treated sludge.

[0055] Standard tests were conducted on the sludge from the three treatments, and the results were used to determine whether the pretreatment of the black and odorous sludge had been completed.

[0056] Understandably, this embodiment aims to propose an innovative pretreatment method specifically for the treatment of black and odorous sludge. This method meticulously encompasses multiple steps to ensure thorough and effective treatment of the sludge. First, in the first step, a combination of high temperature and ultraviolet light is used to remove biological components from the sludge. The purpose of this step is to eliminate harmful organisms in the sludge and eliminate their malodorous emissions, thereby obtaining sludge after primary treatment. Next, in the second step, biodegradation and chemical oxidation methods are used to further treat the sludge after primary treatment to remove organic matter, resulting in secondary-treated sludge. This step is crucial for reducing the organic matter content in the sludge, as organic matter is one of the main causes of black and odorous conditions. Subsequently, in the third step, various physical and chemical methods such as sedimentation, filtration, and adsorption are used to remove inorganic matter from the secondary-treated sludge to achieve purification, thereby obtaining tertiary-treated sludge. Finally, in the fourth step, a series of standard tests are conducted on the sludge after tertiary treatment. The test results are used to determine whether the pretreatment of the black and odorous sludge has achieved the expected results, ensuring that the quality of the treated sludge meets relevant standard requirements. Through this series of meticulous operational procedures, the pretreatment method proposed in this embodiment can effectively solve the problem of black and odorous sludge, laying a solid foundation for subsequent treatment and resource utilization.

[0057] In a preferred embodiment of the present invention, the biological components of black and odorous sludge are removed using high temperature and ultraviolet light to obtain sludge treated in a single step, including:

[0058] The black and smelly sludge is heated and simultaneously irradiated with ultraviolet light;

[0059] The heating temperature is determined based on the mass, volume, and initial moisture content of the black and odorous sludge. The calculation formula is as follows:

[0060] Heating temperature = (mass of black and smelly sludge * initial moisture content) / (volume * coefficient A) + reference temperature;

[0061] Wherein, coefficient A is an empirical value; and the reference temperature is the set minimum value.

[0062] It is understood that this preferred embodiment utilizes a combination of high temperature and ultraviolet light to remove biological components from black and odorous sludge, aiming to achieve significant purification of the sludge in a single treatment process. The specific treatment steps include: first, heating the black and odorous sludge while simultaneously irradiating it with ultraviolet light to accelerate the decomposition and removal of biological components; second, determining a suitable heating temperature based on the specific mass, volume, and initial moisture content of the black and odorous sludge; in this calculation formula, coefficient A is an empirical value determined based on experimental data and practical application experience, while the reference temperature is a pre-set minimum temperature value, its function being to ensure that the sludge can reach and maintain the necessary temperature during the treatment process to achieve effective removal of biological components. This treatment method not only improves treatment efficiency and reduces treatment costs but also effectively improves the sanitary conditions of the sludge and reduces environmental pollution.

[0063] In a preferred embodiment of the present invention, the biological components of black and odorous sludge are removed using high temperature and ultraviolet light to obtain sludge treated in a single step, including:

[0064] The ultraviolet radiation intensity is determined based on the mass, volume, and initial organic composition ratio of the black and odorous sludge. The calculation formula is as follows:

[0065] UV intensity = (mass of black and odorous sludge * initial organic component ratio) / (volume * coefficient B) + reference intensity;

[0066] Wherein, coefficient B is an empirical value; and the benchmark strength is the set minimum strength.

[0067] Understandably, this preferred embodiment employs a highly efficient method to remove biological components from black and odorous sludge through the combined action of high temperature and ultraviolet light. During the one-time sludge treatment process, the appropriate ultraviolet light intensity is determined based on the mass, volume, and initial organic component ratio of the black and odorous sludge. In this calculation formula, coefficient B is an empirical value, summarized from long-term experiments and practice, used to adjust the relationship between ultraviolet light intensity and the properties of the black and odorous sludge. The baseline intensity is a pre-set minimum intensity, its purpose being to ensure that the ultraviolet light intensity does not fall below this value under any circumstances, thereby guaranteeing the treatment effect. This method not only effectively removes biological components from black and odorous sludge but also improves treatment efficiency and reduces environmental impact.

[0068] In a preferred embodiment of the present invention, when using biodegradation and chemical oxidation to remove organic matter from primary treated sludge to obtain secondary treated sludge, the process includes:

[0069] Biodegradation involves adding microbial agents to the primary treated sludge to decompose the organic matter in the sludge.

[0070] Microbial agents include nitrifying bacteria and auxiliary bacteria, among which the auxiliary bacteria are thermophilic steatobacterium.

[0071] It is understood that this preferred embodiment employs biodegradation and chemical oxidation methods to remove organic matter from the primary treated sludge. When secondary treated sludge is obtained, the treatment process includes the following steps: First, a specially formulated microbial agent is added to the primary treated sludge using a biodegradation method. This agent effectively decomposes the organic matter in the sludge. Second, the microbial agent used mainly consists of nitrifying bacteria and auxiliary bacteria, with the auxiliary bacteria specifically selected as *Bacillus stearothermophilus*. This series of treatment processes not only effectively removes organic matter from the sludge but also improves the sludge treatment efficiency, reduces energy consumption and environmental impact during the treatment process, and has excellent application prospects.

[0072] It is important to emphasize that *Bacillus thermophilus* promotes the effect of nitrifying bacteria. This is because *Bacillus thermophilus* possesses extremely high survival ability and metabolic activity under high-temperature conditions, allowing it to rapidly multiply and exert its unique function during sludge treatment. First, by decomposing organic matter in the sludge, *Bacillus thermophilus* provides a rich nutrient source for nitrifying bacteria, thereby promoting their reproduction and activity. Second, during the decomposition of organic matter, *Bacillus thermophilus* produces intermediate products that are beneficial to the nitrification reaction. These products can lower the activation energy of the nitrification reaction and increase the reaction rate. Finally, *Bacillus thermophilus* itself also has a certain oxidizing capacity, which can further accelerate the degradation and transformation of organic matter in the sludge.

[0073] During sludge treatment, a favorable synergistic effect was observed between *Bacillus stearothermophilus* and nitrifying bacteria. Nitrifying bacteria utilized the organic matter and intermediate products generated by *Bacillus stearothermophilus* to carry out nitrification, converting ammonia nitrogen in the sludge into nitrite and nitrate, thereby reducing the ammonia nitrogen content. Simultaneously, *Bacillus stearothermophilus*, by decomposing organic matter and producing intermediate products, provided the necessary conditions for nitrification, promoting its progress. This synergistic effect not only improved the sludge treatment efficiency but also reduced the use of chemical agents, lowering treatment costs and environmental impact.

[0074] In summary, in this preferred embodiment, when treating sludge using biodegradation and chemical oxidation methods, the addition of a microbial agent containing nitrifying bacteria and thermophilic Bacillus stearothermophilus achieves highly efficient removal of organic matter from the sludge. The synergistic effect between thermophilic Bacillus stearothermophilus and nitrifying bacteria not only improves the effectiveness and efficiency of sludge treatment but also reduces treatment costs and environmental impact.

[0075] In a preferred embodiment of the present invention, when using biodegradation and chemical oxidation to remove organic matter from primary treated sludge to obtain secondary treated sludge, the method further includes:

[0076] After the primary treated sludge undergoes biodegradation, it is then chemically oxidized.

[0077] The oxidants used in chemical oxidation are hydrogen peroxide and sodium hypochlorite.

[0078] Understandably, this preferred embodiment employs a highly efficient treatment method that utilizes a combination of biodegradation and chemical oxidation to deeply remove organic matter from the initially treated sludge. The specific operational process is as follows: First, the sludge undergoes biodegradation treatment. Through the action of microorganisms, a large amount of organic matter is decomposed and transformed, thereby reducing the organic matter content in the sludge. Following biodegradation, a chemical oxidation process is introduced to further eliminate residual organic pollutants. In this step, hydrogen peroxide and sodium hypochlorite are specifically selected as oxidants. These two chemicals have strong oxidizing capabilities and can completely convert organic pollutants into harmless substances. This two-pronged treatment strategy not only significantly improves the efficiency of sludge treatment but also ensures that the treated sludge meets higher environmental standards, facilitating the resource utilization and harmless treatment of the sludge. This continuous treatment process not only optimizes the treatment effect but also improves the environmental adaptability and economic rationality of the entire treatment process.

[0079] In a preferred embodiment of the present invention, the chemical oxidation process includes:

[0080] Hydrogen peroxide is evenly sprayed onto the sludge after the primary treatment of biodegradation to carry out the oxidation reaction.

[0081] Then, sodium hypochlorite solution is added to the sludge to carry out an oxidation reaction.

[0082] Understandably, the chemical oxidation process of this preferred embodiment is described in detail below: First, hydrogen peroxide is sprayed uniformly onto the sludge after preliminary treatment through the biodegradation process. This is to ensure that the hydrogen peroxide can fully contact the organic matter in the sludge and undergo an oxidation reaction. The key to this step is the uniform spraying of hydrogen peroxide, which helps to improve oxidation efficiency and ensures that all sludge particles are fully treated. Subsequently, a sodium hypochlorite solution is added to the sludge that has already reacted with hydrogen peroxide to continue the oxidation process. The addition of sodium hypochlorite further enhances the oxidation effect and helps to remove more stubborn organic pollutants from the sludge. Through these two steps of chemical oxidation treatment, the treatment quality of the sludge can be significantly improved, bringing it closer to the requirements of environmental protection and resource recycling. The entire chemical oxidation process not only improves treatment efficiency but also reduces the difficulty of subsequent treatment, contributing to the reduction, harmlessness, and resource recovery of sludge.

[0083] In a preferred embodiment of the present invention, the concentration of hydrogen peroxide is 30%-50%, and the mass ratio of hydrogen peroxide to primary treated sludge is (0.01-0.05):1;

[0084] The concentration of sodium hypochlorite solution is 1%-3%, and the mass ratio of sodium hypochlorite solution to primary treated sludge is (0.005-0.015):1.

[0085] It is understood that this preferred embodiment specifically selects a hydrogen peroxide concentration range of 30% to 50%, because this concentration range ensures that the oxidizing power of hydrogen peroxide is both strong and stable, sufficient to effectively decompose and degrade organic matter in the sludge. Simultaneously, this embodiment also determines that the mass ratio of hydrogen peroxide to the sludge treated in the primary process is (0.01-0.05):1. This ratio ensures that during the treatment process, hydrogen peroxide can fully contact and react with the pollutants in the sludge, improving treatment efficiency.

[0086] In addition, we used sodium hypochlorite solution with a concentration controlled between 1% and 3%. This concentration range allows the sodium hypochlorite solution to exert good disinfection and sterilization effects while ensuring effective oxidative decomposition of the sludge. Furthermore, we determined the mass ratio of sodium hypochlorite solution to primary treated sludge to be between 0.005 and 0.015:1. This ratio ensures thorough mixing of the sodium hypochlorite solution with the sludge during treatment, thereby improving the treatment effect.

[0087] By using the above-selected concentrations and ratios, this embodiment can effectively treat sludge, improve sludge treatment efficiency, reduce treatment costs, and ensure that the treated sludge meets relevant environmental protection standards.

[0088] In a preferred embodiment of the present invention, when inorganic matter is removed from secondary treated sludge using sedimentation, filtration, and adsorption to obtain tertiary treated sludge, the process includes:

[0089] The sludge from the secondary treatment process is allowed to settle naturally before being filtered.

[0090] After filtration, an adsorbent is used to adsorb the secondary treated sludge.

[0091] It is understood that this preferred embodiment employs a series of comprehensive treatment methods, including sedimentation, filtration, and adsorption, to effectively remove inorganic matter from the secondary-treated sludge, thereby obtaining higher-quality tertiary-treated sludge. The specific treatment process includes the following steps:

[0092] First, the sludge that has undergone secondary treatment is placed in a suitable environment and allowed to settle naturally for a certain period of time. This step is to allow suspended solids and most inorganic particulate matter in the sludge to settle to the bottom naturally under gravity, thereby achieving preliminary solid-liquid separation.

[0093] Next, after natural sedimentation, the sludge undergoes filtration. Using specialized filtration equipment, such as sand filters and activated carbon filters, fine particles and some dissolved inorganic substances are further removed from the sludge. This step effectively reduces the suspended solids content in the sludge, improving the efficiency of subsequent treatment.

[0094] Finally, after the filtration step, a specific adsorbent is needed to deeply adsorb the secondary treated sludge. The adsorbent can be various activated carbons, zeolites, or other materials with highly porous structures and adsorption capacity. These materials can effectively adsorb heavy metal ions, nitrogen, phosphorus, and other inorganic pollutants in the sludge, thereby further improving the sludge quality.

[0095] Through the continuous processing of the above three steps, the secondary treated sludge, which originally contained a large amount of inorganic impurities, can be transformed into a purer tertiary treated sludge, more suitable for subsequent applications, after being processed by the method of this invention. This process not only improves the sludge treatment efficiency but also reduces the environmental impact of inorganic pollutants, demonstrating significant environmental benefits and economic value.

[0096] In a preferred embodiment of the present invention, the method for preparing the adsorbent includes:

[0097] After mixing activated carbon and bentonite, the mixture is ground and sieved to obtain a mixture; wherein the ratio of activated carbon to bentonite is 1:(2-3).

[0098] The mixture is activated at 800-1000℃ for 2-4 hours.

[0099] After activation, the mixture is cooled to obtain the adsorbent.

[0100] It is understood that the preparation process of the adsorbent involved in this preferred embodiment includes a series of carefully designed steps aimed at ensuring the high efficiency and excellent properties of the final product. First, high-quality activated carbon is precisely mixed with specially selected bentonite. This step is achieved through mechanical grinding to ensure that the two raw materials are thoroughly mixed and form a homogeneous composite material. To achieve optimal physical and chemical properties, the ratio of activated carbon to bentonite is strictly controlled within the range of approximately 1:2 to 1:3, a ratio carefully calculated to maximize the adsorption capacity and efficiency of the adsorbent.

[0101] Next, the mixed materials are placed in a pre-set high-temperature environment, specifically within the range of 800 to 1000°C, for activation. This high-temperature condition stimulates the chemical reactions within the activated carbon and bentonite, thereby enhancing their specific surface area and adsorption capacity. The activation process is precisely controlled to last between 2 and 4 hours to ensure that the materials undergo sufficient structural reconstruction and performance improvement, while avoiding overheating that could degrade the adsorbent's performance.

[0102] After the activation step, the material needs to be cooled to stabilize its structure and properties. The cooling process is typically carried out under natural conditions or accelerated using cooling equipment in a controlled laboratory environment. Finally, the cooled material is collected and packaged to form the final adsorbent product, which not only meets stringent industrial standards but also exhibits superior performance in adsorbing organic pollutants, gas separation, and other applications.

[0103] In a preferred embodiment of the invention, the particle size of the mixture is 0.1-0.5 mm.

[0104] It is understood that the adsorbent of this preferred embodiment not only possesses the aforementioned carefully designed and highly efficient performance, but the particle size of its mixture is also carefully controlled, falling within the range of 0.1 to 0.5 mm. This particle size range was chosen based on multiple considerations of the adsorbent's performance.

[0105] First, smaller particle size means a larger specific surface area, increasing the contact area between the adsorbent and the target substance, thereby improving adsorption efficiency and capacity. Second, an appropriate particle size distribution ensures uniform distribution of the adsorbent in the flowing medium, preventing localized blockage or excessive accumulation, and guaranteeing the continuity and stability of the adsorption process. Furthermore, adsorbents within this particle size range also exhibit good flowability and handleability, facilitating operation and use in industrial production. Whether using packed beds, fluidized beds, or other forms of adsorption devices, effective utilization and efficient adsorption of the adsorbent can be guaranteed.

[0106] In addition to the aforementioned technical advantages, the adsorbent of this preferred embodiment also offers significant economic and environmental benefits. Due to its high adsorption efficiency and stable performance, it can significantly reduce production costs and energy consumption, while simultaneously minimizing environmental pollution and burden. This adsorbent plays a vital role in various fields such as wastewater treatment, gas purification, and metal recovery.

[0107] In summary, the adsorbent of this preferred embodiment, through careful design and preparation process, achieves a perfect combination of high performance, high efficiency and environmental friendliness, and has broad application prospects and market demand.

[0108] In a preferred embodiment of the present invention, when performing standard tests on the sludge from the three treatments and determining whether the pretreatment of the black and odorous sludge has been completed based on the test results, the following steps are included:

[0109] The sludge from the three treatments was tested for indicators including organic matter content, inorganic matter content, heavy metal content, and biotoxicity.

[0110] The detected index data are compared and analyzed with the preset preprocessing standards;

[0111] When the comparison results show that all indicators of the sludge from the three treatments meet the pretreatment standards, the pretreatment of the black and odorous sludge is considered complete.

[0112] Understandably, this preferred embodiment involves comprehensive and detailed standard testing of the sludge after three treatments to determine whether the pretreatment of the black and odorous sludge has achieved the expected results. This process mainly includes the following key steps:

[0113] First, the treated sludge underwent comprehensive testing. This testing process covered several important aspects, including organic matter content, inorganic matter content, heavy metal content, and biotoxicity. These indicators were selected based on a deep understanding of the characteristics of black and odorous sludge, aiming to comprehensively evaluate the quality of the treated sludge.

[0114] Next, the obtained data from various indicators were compared and analyzed in depth with the pre-set pretreatment standards. This step, through comparative analysis, allows for a direct understanding of whether the treated sludge has met the preset benchmarks in all aspects.

[0115] Finally, after rigorous comparison, if all indicators of the sludge from the three treatments meet the pretreatment standards, then the pretreatment of the black and odorous sludge can be considered successfully completed. This result means that the sludge is ready for further treatment and resource utilization and can proceed to the next stage.

[0116] In summary, this series of testing and judgment steps ensures the quality of pretreatment of black and odorous sludge, thus providing a stable and reliable foundation for subsequent treatment. This also demonstrates the innovation and practicality of this invention in treating black and odorous sludge, aiming to contribute to environmental protection and resource reuse.

[0117] The following is a preferred embodiment of this application.

[0118] Example 1:

[0119] 1. Material preparation:

[0120] 1.1 Microbial inoculants:

[0121] The microbial agent used is a commercially available mixture of nitrifying bacteria (Gandhi algae) and thermophilic steatobacterium CMCC(B)63509, with a ratio of nitrifying bacteria to thermophilic steatobacterium CMCC(B)63509, ensuring efficient decomposition of organic matter during the subsequent biodegradation process. Simultaneously, the activity of the agent is maintained at a high level to guarantee the treatment effect.

[0122] 1.2 Oxidizing agent:

[0123] The hydrogen peroxide used is an industrial-grade product with a concentration of 40%, and the sodium hypochlorite solution is a commercially available product with a concentration of 2%. These two oxidants are used together in the subsequent chemical oxidation step to efficiently remove organic matter from the sludge.

[0124] 1.3 Adsorbent:

[0125] Activated carbon and bentonite were mixed at a weight ratio of 1:2.5, then ground and sieved to obtain a mixture with a particle size of 0.3 mm. The mixture was activated at 900±30℃ for 3 hours. After activation, it was cooled to obtain the adsorbent. This adsorbent showed good adsorption performance in subsequent inorganic matter removal steps.

[0126] 2. Pretreatment of black and odorous sludge:

[0127] 2.1 High temperature and ultraviolet light treatment:

[0128] The black, odorous sludge was placed in a heating device, and the ultraviolet irradiation device was turned on simultaneously. Based on the mass, volume, and initial moisture content of the sludge, the heating temperature was calculated and set to 60℃, and the ultraviolet intensity was set to medium. After 30 minutes of treatment, one batch of treated sludge was obtained.

[0129] 2.2 Biodegradation and Chemical Oxidation:

[0130] Microbial inoculants were added to the primary treated sludge and thoroughly stirred. After the inoculants were evenly distributed in the sludge, it was allowed to stand for 24 hours for biodegradation. After degradation was complete, hydrogen peroxide solution was evenly sprayed into the sludge, and sodium hypochlorite solution was added for chemical oxidation. The oxidation reaction lasted for 2 hours, yielding secondary treated sludge.

[0131] 2.3 Precipitation, Filtration, and Adsorption:

[0132] The secondary-treated sludge was allowed to settle naturally for 24 hours, and then filtered using a filtration device. After filtration, adsorbent was evenly sprinkled on the surface of the sludge and thoroughly stirred. After standing for 4 hours, it was filtered again to obtain tertiary-treated sludge.

[0133] 3. Standard testing and judgment:

[0134] The organic matter content, inorganic matter content, heavy metal content, and biotoxicity of the sludge from the three treatments were tested. The obtained data were compared with the preset pretreatment standards. In this embodiment, all indicators met the pretreatment standards, therefore the pretreatment of the black and odorous sludge was deemed complete. The specific testing methods and results are as follows:

[0135] For the sludge after three treatments, this embodiment used high-performance liquid chromatography (HPLC) to determine the organic matter content. HPLC technology is widely used in the field of organic matter analysis due to its high sensitivity, high resolution, and rapid analysis. The results showed that the organic matter content in the sludge after three treatments was significantly reduced, reaching below the preset pretreatment standard.

[0136] The inorganic content was determined using atomic absorption spectrometry (AAS) and ion chromatography (IC). AAS is mainly used for the determination of metallic elements, while IC focuses on the analysis of non-metallic anions. The combination of these two methods allowed for a comprehensive understanding of the composition and content of inorganic matter in the sludge. The results showed that the inorganic content decreased significantly after three treatments and met the pretreatment standards.

[0137] The detection of heavy metal content is a crucial step in the pretreatment process, as it directly affects the safety and environmental friendliness of the sludge. This embodiment employs inductively coupled plasma mass spectrometry (ICP-MS) for quantitative analysis of heavy metals. ICP-MS is renowned for its high sensitivity, low detection limits, and ability to simultaneously analyze multiple elements. The results showed that the heavy metal content in the sludge after three treatments was consistently below the preset pretreatment standard.

[0138] Regarding the detection of biotoxicity, this embodiment employed a biological testing method. This method assesses the biotoxicity of the sludge by observing the growth, reproduction, and survival of specific organisms exposed to the sludge. The results showed that the treated sludge had no significant toxicity to the test organisms and met the pretreatment standards.

[0139] In summary, the black and odorous sludge treated three times met the preset pretreatment standards in terms of organic matter content, inorganic matter content, heavy metal content, and biotoxicity.

[0140] As can be seen from the above embodiments, the pretreatment method of this application can effectively remove biological components, organic matter and inorganic matter from black and odorous sludge, reduce heavy metal content and biotoxicity, and lay the foundation for subsequent sludge resource utilization or safe disposal.

[0141] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

[0142] Apart from the technical features described in the specification, the other technical features are known to those skilled in the art. To highlight the innovative features of this invention, the other technical features will not be described in detail here.

Claims

1. A pretreatment method for black and odorous sludge, characterized in that, Includes the following steps: The biological components of black and odorous sludge are removed by using high temperature and ultraviolet light to obtain primary treated sludge. Organic matter is removed from primary treated sludge using biodegradation and chemical oxidation to obtain secondary treated sludge. The inorganic matter in the secondary treated sludge is removed by sedimentation, filtration and adsorption to obtain tertiary treated sludge. Standard tests were conducted on the sludge from the three treatments, and the results were used to determine whether the pretreatment of the black and odorous sludge had been completed. Using high temperature and ultraviolet light to remove biological components from black and odorous sludge, a single sludge treatment process includes: The black and smelly sludge is heated and simultaneously irradiated with ultraviolet light; The heating temperature is determined based on the mass, volume, and initial moisture content of the black and odorous sludge. The calculation formula is as follows: Heating temperature = (mass of black and smelly sludge × initial moisture content) / (volume × coefficient A) + reference temperature; Wherein, coefficient A is an empirical value; the reference temperature is the set minimum value; Using high temperature and ultraviolet light to remove biological components from black and odorous sludge, a single sludge treatment process includes: The ultraviolet radiation intensity is determined based on the mass, volume, and initial organic composition ratio of the black and odorous sludge. The calculation formula is as follows: UV intensity = (mass of black and odorous sludge × initial organic component ratio) / (volume × coefficient B) + reference intensity; Wherein, coefficient B is an empirical value; the benchmark strength is the set minimum strength; When conducting standard tests on the sludge from the three treatments and determining whether the pretreatment of black and odorous sludge has been completed based on the test results, the following steps are included: The sludge from the three treatments was tested for indicators, including organic matter content, inorganic matter content, heavy metal content, and biotoxicity. The detected index data are compared and analyzed with the preset preprocessing standards; When the comparison results show that all indicators of the three treated sludge samples meet the pretreatment standards, the pretreatment of the black and odorous sludge is deemed complete.

2. The pretreatment method for black and odorous sludge according to claim 1, characterized in that, In the process of removing organic matter from primary treated sludge using biodegradation and chemical oxidation to obtain secondary treated sludge, the biodegradation includes adding microbial agents to the primary treated sludge to decompose organic matter in the sludge. The microbial agent includes nitrifying bacteria and auxiliary bacteria, wherein the auxiliary bacteria are thermophilic Bacillus stearothermophilus.

3. The pretreatment method for black and odorous sludge according to claim 2, characterized in that, Also includes: After the primary treated sludge undergoes biodegradation, it is then chemically oxidized. The oxidants used in the chemical oxidation process are hydrogen peroxide and sodium hypochlorite.

4. The pretreatment method for black and odorous sludge according to claim 3, characterized in that, Chemical oxidation includes: Hydrogen peroxide is evenly sprayed onto the primary treated sludge after biodegradation to carry out an oxidation reaction. Then, sodium hypochlorite solution is added to the sludge to carry out an oxidation reaction.

5. The pretreatment method for black and odorous sludge according to claim 4, characterized in that, The concentration of hydrogen peroxide is 30%-50%, and the mass ratio of hydrogen peroxide to primary treated sludge is (0.01-0.05):1; The concentration of the sodium hypochlorite solution is 1%-3%, and the mass ratio of the sodium hypochlorite solution to the primary treated sludge is (0.005-0.015):

1.

6. The pretreatment method for black and odorous sludge according to claim 1, characterized in that, When using sedimentation, filtration, and adsorption to remove inorganic matter from secondary treated sludge to obtain tertiary treated sludge, the process includes: The sludge from the secondary treatment process is allowed to settle naturally before being filtered. After filtration, an adsorbent is used to adsorb the filtered sludge.

7. The pretreatment method for black and odorous sludge according to claim 6, characterized in that, The method for preparing the adsorbent includes: After mixing activated carbon and bentonite, the mixture is ground and sieved to obtain a mixture; wherein the mass ratio of activated carbon to bentonite is 1:(2-3). The mixture is activated at 800-1000℃ for 2-4 hours. After activation, the adsorbent is cooled to obtain the adsorbent.