Oily sludge pyrolysis residue soil treatment method and device
By mixing and fermenting oily sludge pyrolysis residue with bacterial residue, vermiculite, straw, and humic acid, a soil amendment product with high organic matter and strong active microorganisms is formed, which solves the problem that pyrolysis residue cannot be directly utilized and realizes resource utilization and environmental safety.
Patent Information
- Application Number
- CN202511487936.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-17
- Publication Date
- 2026-02-10
AI Technical Summary
Oily sludge pyrolysis residue is difficult to use directly as a soil amendment material due to its low organic matter content, poor microbial activity, loose structure, and unsuitable pH value. Existing treatment methods such as landfill and stabilization treatment involve resource waste and environmental risks, and cannot achieve resource utilization.
The pyrolysis residue of oily sludge is mixed with bacterial residue, vermiculite, straw, and humic acid in a specific ratio. The composting process is carried out by controlling the fermentation temperature, moisture content, and time, resulting in a soil amendment product with good physical structure, rich nutrients, and an active microbial community.
This method enables the resource utilization of pyrolysis residue containing oily sludge. The product has high organic matter content, strong microbial activity, and excellent physical properties, making it suitable for plant growth. It also reduces the content of heavy metals and solves multiple problems associated with pyrolysis residue.
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Figure CN121494643A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of solid waste treatment, and particularly relates to a method and device for soilizing oil sludge pyrolysis residue. BACKGROUND
[0002] Oil sludge is a major hazardous waste generated in the process of oil exploitation, refining and storage, which contains a large amount of petroleum hydrocarbons, heavy metals and other harmful substances. With the rapid development of the oil industry, more than 5 million tons of oil sludge is generated in China every year, and its treatment and disposal has become an important issue in the field of environmental protection.
[0003] Pyrolysis technology, as one of the main methods for harmless treatment of oil sludge, can effectively remove organic pollutants and recover oil resources through high-temperature decomposition. However, the pyrolysis residue generated after pyrolysis still accounts for 60-80% of the weight of the original sludge, which becomes an important constraint for the popularization and application of pyrolysis technology.
[0004] Although the organic pollutant content of oil sludge pyrolysis residue is greatly reduced, there are still many problems in its own characteristics. First, the organic matter content of pyrolysis residue is generally low, usually between 10-15%, which is far lower than the requirement of more than 30% organic matter content of high-quality soil, and lacks the nutrient basis required for plant growth. Second, the high-temperature pyrolysis process destroys the original soil structure, resulting in small particle size, loose structure, low bulk density, lack of good aggregate structure, poor air permeability and water retention of pyrolysis residue. Third, the high-temperature treatment in the pyrolysis process kills most of the microorganisms, and the pyrolysis residue basically does not exist active microbial community, lacking the necessary biological activity in the soil ecosystem. In addition, the pyrolysis residue is usually alkaline, with a pH value of 8.0-9.5, which is not suitable for the normal growth of most plants.
[0005] Due to the above problems, oil sludge pyrolysis residue cannot be directly used as soil improvement material. At present, a large amount of pyrolysis residue is mainly treated by landfill or simple stabilization. Landfill treatment not only occupies a large amount of land resources, but also has long-term environmental risks. With the increasing strictness of environmental protection requirements, the cost of landfill treatment is rising, and the sustainability is poor. Although the stabilization treatment can solidify harmful substances such as heavy metals to meet the requirements of safe landfill, the treated product still lacks practical application value and cannot realize real resource utilization, which is essentially still an end-of-pipe disposal rather than resource recovery. SUMMARY
[0006] The present application provides a method and device for soilizing oil sludge pyrolysis residue, which can convert oil sludge pyrolysis residue into soil improvement products with good physical structure, rich nutrient components and active microbial community, realizing the resource utilization of waste.
[0007] In a first aspect, the present invention provides a method for soilification of oily sludge pyrolysis residue, comprising the following steps: raw material preparation: mixing 40-50 parts of oily sludge pyrolysis residue, 35-40 parts of bacterial residue, 4-10 parts of vermiculite, 9-15 parts of straw, and 1-3 parts of humic acid by weight; fermentation treatment: composting the prepared raw materials, controlling the fermentation temperature at 30℃ to 60℃, the material moisture content at 55-65%, and the fermentation time at 20-90 days, with intermittent stirring and aeration during the fermentation process; and obtaining the soilification product of oily sludge pyrolysis residue.
[0008] In one possible implementation, the weight proportions of each component in the raw material formulation are as follows: 41.7-47.2 parts of oily sludge pyrolysis residue, 36.3-38.5 parts of fungal residue, 1.3-2.5 parts of humic acid, 4-6 parts of vermiculite, and 9-14 parts of straw.
[0009] In one possible implementation, the fermentation process includes: a first stage at a temperature controlled at 45-55°C for 15-25 days; and a second stage at a temperature controlled at 35-45°C for 15-65 days.
[0010] In one possible implementation, the first stage stirring interval is 1-2 hours, and the second stage stirring interval is 4-6 hours.
[0011] In one possible implementation, intermittent stirring employs alternating forward and reverse stirring methods, with each stirring session lasting 10-30 minutes.
[0012] In one possible implementation, the pH of the mixed raw materials is adjusted before fermentation by adding quicklime or potassium dihydrogen phosphate to control the pH value within the range of 6.5-7.5.
[0013] In one possible implementation, temperature and humidity sensors are installed during the fermentation process to monitor the material temperature and moisture content in real time, and the aeration rate and water replenishment are adjusted according to the monitoring results.
[0014] In one possible implementation, the ratio of raw materials is determined through a four-step superimposed experiment: a single-component experiment of mushroom residue, a combined-component experiment of mushroom residue and humic acid, a combined-component experiment of mushroom residue, humic acid and vermiculite, and a combined-component experiment of mushroom residue, humic acid, vermiculite and straw are carried out in sequence, and the optimal ratio is determined with plant germination rate and plant height as evaluation indicators.
[0015] Secondly, the present invention provides an apparatus for the above-mentioned method of soilification of pyrolysis residue of oily sludge, comprising: a fermentation tank; a stirring system, including an auger shaft disposed inside the fermentation tank and a drive motor disposed outside the fermentation tank, the surface of the auger shaft being fitted with wave-shaped stirring blades; a heating system; a feeding and discharging system; a water feeding and discharging system; and a gas feeding and discharging system.
[0016] In one possible implementation, the left and right sections of the auger shaft are designed with opposite spiral threads, which drive the material to move in different directions.
[0017] This invention provides a method for soil conversion of oily sludge pyrolysis residue. The method involves mixing the oily sludge pyrolysis residue with five components—microbial residue, vermiculite, straw, and humic acid—in a specific weight ratio, followed by controlled temperature, moisture content, and time for composting fermentation. This solves the technical problem of directly utilizing oily sludge pyrolysis residue. Microbial residue, as a byproduct of fermentation industry, is rich in organic matter and active microbial communities, increasing the organic matter content of the mixture and providing microbial inoculum for the fermentation process, thus addressing the problems of low organic matter content and lack of microbial activity in pyrolysis residue. Vermiculite, with its layered silicate structure and porous characteristics, improves the material's air permeability and water retention, addressing the defects of loose structure and poor physical properties in pyrolysis residue. Straw, rich in cellulose, hemicellulose, and lignin, provides carbon source nutrition for microbial fermentation; its fibrous structure improves the material's aggregate state and regulates the carbon-nitrogen ratio during composting. Humic acid, as a natural organic macromolecule, has complexing and buffering properties, enhancing soil fertility and adjusting pH to a neutral range. During fermentation, the microorganisms in the residue multiply and metabolize using straw and other organic matter as a substrate. They secrete enzymes to decompose macromolecular organic matter, and the resulting metabolites form stable organic-inorganic complexes with humic acid and vermiculite, creating a soil-based product with good physical structure, rich nutrients, and an active microbial community. A fermentation temperature of 30-60℃ ensures normal microbial growth and metabolism, while a moisture content of 55-65% provides a suitable environment for microbial activity. A fermentation time of 20-90 days ensures the full conversion of organic matter and the stable establishment of the microbial community. Intermittent stirring and aeration maintain an aerobic state during fermentation. Through this method, oily sludge pyrolysis residue is transformed into a soil amendment product with high organic matter content, strong microbial activity, and excellent physical properties, achieving the resource utilization of waste. Attached Figure Description
[0018] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0019] Figure 1 This is a flowchart of a method for converting oily sludge pyrolysis residue into soil, provided by the present invention.
[0020] Figure 2This is a three-dimensional structural schematic diagram of a soil conversion device for oily sludge pyrolysis residue provided by the present invention.
[0021] Figure 3 This is a three-dimensional structural schematic diagram of an oily sludge pyrolysis residue soilification device provided by the present invention from another angle.
[0022] Figure 4 This is a top view schematic diagram of a soil conversion device for oily sludge pyrolysis residue provided by the present invention.
[0023] Figure 5 This is a schematic diagram of the planar structure of a soil conversion device for oily sludge pyrolysis residue provided by the present invention.
[0024] Figure 6 yes Figure 5 A schematic diagram of the cross-sectional structure along the AA direction.
[0025] Figure label: 1. Fermentation chamber; 2. Agitator system; 21. Screw shaft; 22. Corrugated agitator blades; 3. Heating system; 4. Feeding and discharging system; 5. Water inlet and outlet system; 51. Sprayer; 52. Water baffle; 53. Water tank; 54. Drain valve; 6. Air intake and exhaust system; 7. Base; 71. Limit knob. Detailed Implementation
[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.
[0027] The following is combined with Figure 1 The present invention describes a method for converting oily sludge pyrolysis residue into soil, comprising the following steps: S1. Raw material preparation: Mix 40-50 parts of oily sludge pyrolysis residue, 35-40 parts of fungal residue, 4-10 parts of vermiculite, 9-15 parts of straw, and 1-3 parts of humic acid by weight. S2. Fermentation treatment: The prepared raw materials are composted and fermented, with the fermentation temperature controlled at 30℃ to 60℃, the material moisture content at 55-65%, and the fermentation time at 20-90 days. Intermittent stirring and aeration are carried out during the fermentation process. S3. Obtain soil-based products from the pyrolysis residue of oily sludge.
[0028] This invention solves the technical problem of directly utilizing oily sludge pyrolysis residue by mixing it with five components—microbial residue, vermiculite, straw, and humic acid—in a specific weight ratio, followed by controlled temperature, moisture content, and time for composting fermentation. Microbial residue, a byproduct of fermentation industry, is rich in organic matter and active microbial communities, increasing the organic matter content of the mixture and providing microbial inoculum for the fermentation process, thus addressing the problems of low organic matter content and lack of microbial activity in pyrolysis residue. Vermiculite, with its layered silicate structure and porous characteristics, improves the material's air permeability and water retention, overcoming the defects of loose structure and poor physical properties in pyrolysis residue. Straw, rich in cellulose, hemicellulose, and lignin, provides carbon source nutrition for microbial fermentation, and its fibrous structure improves the material's aggregate state and regulates the carbon-nitrogen ratio during composting. Humic acid, as a natural organic macromolecule, possesses complexing and buffering properties, enhancing soil fertility and adjusting pH to a neutral range. During the fermentation process, the microorganisms in the fermentation residue multiply and metabolize using organic matter such as straw as a substrate, secreting enzymes to decompose macromolecular organic matter. The resulting metabolites form a stable organic-inorganic complex with humic acid, vermiculite, etc., constructing a soil-based product with good physical structure, rich nutrients, and an active microbial community. This transforms the pyrolysis residue of oily sludge into a soil amendment product with high organic matter content, strong microbial activity, and excellent physical properties, realizing the resource utilization of waste.
[0029] Specifically, maintaining a fermentation temperature between 30℃ and 60℃ is crucial for the normal growth and reproduction of most aerobic microorganisms. Temperatures that are too low will inhibit microbial activity and prolong the fermentation cycle, while temperatures that are too high will kill beneficial microorganisms and negatively impact the fermentation effect. A material moisture content of 55-65% provides a suitable environment for microorganisms; too low a moisture content restricts microbial metabolism, while too high a moisture content can easily create an anaerobic environment that produces foul-smelling gases. A fermentation time of 20-90 days ensures the complete decomposition and transformation of organic matter. Intermittent stirring ensures uniform mixing of the material and avoids localized anaerobic conditions. Aeration is essential to maintain an aerobic environment during the fermentation process.
[0030] In related technologies, oily sludge pyrolysis residue is mainly treated by landfill or stabilization. Landfill disposal occupies land resources and poses environmental risks, while stabilization, although it can solidify harmful substances, cannot achieve resource utilization, and the treated product lacks practical application value. However, in this invention, through five-component synergistic improvement and fermentation process control, multiple problems such as insufficient organic matter, poor microbial activity, and poor soil structure in oily sludge pyrolysis residue are simultaneously solved. Microbial residue and humic acid provide organic matter and microorganisms, vermiculite and straw improve the physical structure, and the synergistic effect of multiple components gives the final product excellent agricultural soil properties, transforming waste that would otherwise require landfill disposal into a valuable soil amendment product, thus achieving resource utilization.
[0031] In some embodiments, the weight parts of each component in the raw material formulation are as follows: 41.7-47.2 parts of oily sludge pyrolysis residue, 36.3-38.5 parts of fungal residue, 1.3-2.5 parts of humic acid, 4-6 parts of vermiculite, and 9-14 parts of straw.
[0032] In this invention, the weight proportions of each component are further limited to 41.7-47.2 parts of oily sludge pyrolysis residue, 36.3-38.5 parts of microbial residue, 1.3-2.5 parts of humic acid, 4-6 parts of vermiculite, and 9-14 parts of straw. This narrowing of the proportion range improves the stability of product quality. The oily sludge pyrolysis residue provides a moderate proportion as the main matrix, the microbial residue provides sufficient organic matter and microbial inoculum, the appropriate addition of humic acid enhances the product's fertilizer retention capacity, and the ratio of vermiculite and straw improves soil physical properties without excessively diluting the main components.
[0033] Specifically, the proportion of 41.7-47.2 parts of oily sludge pyrolysis residue ensures the dominant role of the substrate, providing ample space for other amendment components to function. The addition of 36.3-38.5 parts of microbial residue provides sufficient microbial flora and organic matter to support the smooth progress of the entire fermentation process. The dosage of 1.3-2.5 parts of humic acid is economical and reasonable, achieving the amendment effect while avoiding excessive costs. The ratio of 4-6 parts of vermiculite and 9-14 parts of straw effectively regulates soil bulk density and pore structure, improving aeration and water retention.
[0034] In one specific embodiment, a method for soil treatment of oily sludge pyrolysis residue suitable for the growth of *Ilex chinensis* seeds is provided: 1000 kg of oily sludge pyrolysis residue is mixed with 870 kg of fungal residue, 60 kg of humic acid, 144 kg of vermiculite, and 336 kg of straw, with a mixing weight ratio of residue:fungal residue:humic acid:vermiculite:straw = 41.7%:36.3%:2.5%:6%:14%. The mixture is piled into a trapezoidal pile, the moisture content is adjusted to 60%, and the fermentation temperature is controlled within the range of 40-50℃ for 60 days of composting fermentation. During the fermentation process, the pile is turned and stirred every 7 days, and an appropriate amount of water is added to maintain a stable moisture content.
[0035] The physicochemical properties of the fermented soil product showed a pH of 7.1, a bulk density of 0.76 g / cm³, a water-soluble salt content of 980 mg / kg, and a significant increase in organic matter content. Seed planting trials with *Ilex cornuta* showed a germination rate of 83%, a 60-day survival rate of 86%, an average plant height of 13.7 cm, and an average leaf width of 2.1 mm, all indicating good growth. After planting, the soil cadmium content decreased by 61.39%, zinc content decreased by 88.39%, and other heavy metals decreased by 25%-82%, indicating that the soil product has good heavy metal passivation effects and environmental safety.
[0036] In another specific embodiment, a method for soil treatment of oily sludge pyrolysis residue suitable for ryegrass seed growth is provided: 1000 kg of oily sludge pyrolysis residue is mixed with 816 kg of fungal residue, 28 kg of humic acid, 85 kg of vermiculite, and 191 kg of straw, with a mixing weight ratio of residue:fungal residue:humic acid:vermiculite:straw = 47.2%:38.5%:1.3%:4%:9%. The mixture is piled into a trapezoidal pile, the moisture content is adjusted to 58%, and the fermentation temperature is controlled within the range of 35-45℃ for 60 days of composting fermentation. During the fermentation process, the pile is turned and stirred every 7 days, and the temperature and moisture content are monitored regularly and adjusted in a timely manner to ensure stable fermentation conditions.
[0037] The physicochemical properties of the fermented soil product were tested, showing a pH of 7.3, a bulk density of 0.77 g / cm³, and a water-soluble salt content of 731 mg / kg. Ryegrass seed planting trials showed a germination rate of 88%, a 60-day survival rate of 77%, an average plant height of 29.7 cm, and an average leaf width of 4.2 mm, indicating good plant growth. After planting, the soil cadmium content decreased by 80.24%, zinc content decreased by 68.37%, and heavy metals such as chromium, copper, and nickel decreased by 25%-82%, validating the heavy metal removal effect and practical application value of this soil product.
[0038] In some embodiments, the fermentation process includes: a first stage at a temperature controlled at 45-55°C for 15-25 days; and a second stage at a temperature controlled at 35-45°C for 15-65 days.
[0039] In this invention, a staged fermentation process is employed. The first stage involves maintaining a temperature of 45-55℃ for 15-25 days, while the second stage involves maintaining a temperature of 35-45℃ for 15-65 days. Temperature control is implemented based on the natural laws of the fermentation process and the characteristics of microbial community succession. The higher temperature in the first stage facilitates rapid initiation of the fermentation process, while the moderate temperature in the second stage promotes the stability of the microbial community and the deep transformation of organic matter.
[0040] Specifically, the first stage, with a temperature range of 45-55℃, rapidly activates the activity of mesophilic and thermophilic bacteria, accelerating the decomposition of recalcitrant organic matter such as cellulose and hemicellulose. This process, lasting 15-25 days, ensures thorough high-temperature fermentation while simultaneously killing pathogens and weed seeds. The second stage, with a temperature of 35-45℃, promotes the reproduction of beneficial microorganisms such as actinomycetes, which produce various enzymes that further transform organic matter. This 15-65-day duration ensures thorough fermentation while avoiding over-fermentation and subsequent organic matter loss.
[0041] In one specific embodiment, a staged temperature-controlled treatment method was used to process petroleum sludge pyrolysis residue containing heavy metal ions. The first stage of high-temperature fermentation effectively passivated the heavy metal ions, while the second stage of medium-temperature fermentation promoted the formation of organic chelates. The final product had a heavy metal leaching concentration reduced to below the safety standard and could be safely used for soil improvement.
[0042] In related technologies, composting fermentation typically employs natural heating or constant temperature control. Natural fermentation suffers from temperature variations that are difficult to control precisely, easily leading to excessively high or low temperatures. Constant temperature fermentation, on the other hand, cannot adapt to the varying temperature requirements of different fermentation stages. These methods often result in incomplete fermentation or damage to the activity of beneficial microorganisms. In this invention, staged temperature control fully considers the changing patterns of the microbial community during fermentation. The high temperature in the first stage rapidly decomposes organic matter and kills harmful microorganisms, while the medium temperature in the second stage promotes the reproduction of beneficial microorganisms and the stabilization of organic matter. This method significantly improves fermentation efficiency and product quality, resulting in soil-derived products with higher microbial activity and more stable organic matter content.
[0043] In some embodiments, the first stage stirring interval is 1-2 hours, and the second stage stirring interval is 4-6 hours.
[0044] In this invention, the stirring interval for the first stage is 1-2 hours, and the stirring interval for the second stage is 4-6 hours. The stirring frequency is set according to the material characteristics and microbial activity patterns at different fermentation stages. Frequent stirring in the first stage ensures sufficient oxygen supply and uniform temperature, while moderate stirring in the second stage maintains the stability of the microbial community.
[0045] Specifically, in the first stage, microbial metabolism is active and generates a lot of heat. A stirring interval of 1-2 hours can dissipate heat in time to prevent local overheating, while simultaneously allowing fresh air to be fully mixed into the material to maintain an aerobic environment. Frequent stirring can also promote thorough mixing of different components, providing a uniform nutrient environment for microorganisms. In the second stage, microbial activity tends to stabilize. A stirring interval of 4-6 hours can maintain necessary ventilation while avoiding excessive stirring that could damage the established microbial community structure.
[0046] In some embodiments, intermittent stirring is performed by alternating forward and reverse stirring, with each stirring session lasting 10-30 minutes.
[0047] In this invention, intermittent stirring is carried out by alternating forward and reverse stirring, with each stirring session lasting 10-30 minutes. By changing the stirring direction, the mixing dead zones that are easily generated by traditional unidirectional stirring are eliminated, ensuring that all components are fully contacted and reacted during the fermentation process.
[0048] Specifically, forward stirring pushes the material from one end to the other, while reverse stirring generates the opposite flow of material. Alternating between these two directions creates a complex convection cycle within the fermentation vessel. A stirring time of 10-30 minutes ensures thorough mixing while avoiding excessive damage to the material structure caused by prolonged stirring. Alternating forward and reverse stirring is particularly suitable for composite substrates containing fibrous materials such as straw, effectively preventing fibers from tangling on the mixer and affecting the mixing effect.
[0049] In one specific embodiment, when processing a mixture containing a large amount of straw fiber, alternating forward and reverse stirring avoids the fiber from tangling and accumulating on the stirring shaft. During the fermentation process, the material maintains good fluidity, and the final product has a uniform fiber distribution and excellent granular structure.
[0050] In this embodiment of the invention, alternating forward and reverse stirring effectively solves the technical defects of unidirectional stirring. By changing the stirring direction, it achieves all-round mixing of materials, significantly improving the uniformity of fermentation. This stirring method is particularly suitable for processing mixtures with complex components, ensuring the stable progress of the fermentation process and the consistency of product quality.
[0051] In some embodiments, the pH of the mixed raw materials is adjusted before fermentation by adding quicklime or potassium dihydrogen phosphate to control the pH value within the range of 6.5-7.5.
[0052] In this invention, the pH of the mixed raw materials is adjusted before fermentation by adding quicklime or potassium dihydrogen phosphate to control the pH value within the range of 6.5-7.5, creating the most suitable chemical environment for microbial reproduction. Due to the properties of the raw materials and the pyrolysis conditions, the pH value of oily sludge pyrolysis residue often deviates from the neutral range, which is unfavorable for the growth and reproduction of most beneficial microorganisms.
[0053] Specifically, pH 6.5-7.5 is the optimal growth range for major fermenting microorganisms such as bacteria and actinomycetes, under which enzyme activity is highest and organic matter decomposition efficiency is best. Quicklime is suitable for neutralizing acidic materials; its alkalinity can rapidly raise the pH value, and the released calcium ions help improve soil aggregate structure. Potassium dihydrogen phosphate is suitable for regulating alkaline materials; its acidity can lower the pH value, while providing plants with essential phosphorus and potassium nutrients.
[0054] In this embodiment of the invention, pH pre-adjustment before fermentation ensures that the microorganisms are in the optimal growth environment from the start of fermentation, significantly shortening the fermentation start-up time and improving the stability and controllability of the fermentation process. This method provides important process assurance for the stable production of high-quality soil-based products.
[0055] In some embodiments, temperature and humidity sensors are installed during the fermentation process to monitor the material temperature and moisture content in real time, and the aeration rate and water replenishment are adjusted according to the monitoring results.
[0056] In this invention, temperature and humidity sensors are installed during the fermentation process to monitor the material temperature and moisture content in real time. Based on the monitoring results, the aeration rate and moisture replenishment are adjusted, replacing traditional manual judgment and experience-based control with intelligent technology. Real-time monitoring technology can promptly detect abnormalities during the fermentation process and maintain optimal fermentation conditions through an automatic adjustment system.
[0057] Specifically, the temperature and humidity sensors continuously monitor temperature changes and moisture content fluctuations within the material. When the temperature exceeds the set range, the system automatically adjusts the ventilation rate. Increasing ventilation removes excess heat to cool the material, while decreasing ventilation reduces heat loss and maintains its temperature. When the moisture content deviates from the suitable range, the system automatically activates a spray system to replenish moisture or increases ventilation to promote evaporation. Real-time feedback of the monitoring data ensures that fermentation conditions are always optimal.
[0058] In some embodiments, the ratio of raw materials is determined by a four-step superimposed experiment: a single-component experiment of mushroom residue, a combined-component experiment of mushroom residue and humic acid, a combined-component experiment of mushroom residue, humic acid and vermiculite, and a combined-component experiment of mushroom residue, humic acid, vermiculite and straw are carried out in sequence, and the optimal ratio is determined with plant germination rate and plant height as evaluation indicators.
[0059] In this invention, the proportions of raw materials are determined through a four-step superimposed experiment: single-component experiment with mushroom residue, combined experiment with mushroom residue and humic acid, combined experiment with mushroom residue, humic acid, and vermiculite, and combined experiment with mushroom residue, humic acid, vermiculite, and straw. The optimal proportions are determined using plant germination rate and plant height as evaluation indicators. This experimental method can systematically evaluate the independent effects and synergistic effects of each component, providing a reliable experimental basis for scientifically determining the optimal proportions.
[0060] Specifically, the four-step superimposed experiment adopted a progressive design, with each step adding an improvement component based on the previous one, clearly identifying the contribution of each component to the soil improvement effect. The single-component experiment with mushroom residue determined the basic improvement effect of the mushroom residue; the combined experiment of mushroom residue and humic acid evaluated the synergistic effect of humic acid; and subsequent experiments evaluated the improvement contributions of vermiculite and straw. Plant germination rate and plant height, as evaluation indicators, directly reflect the actual application effect of the soil improvement product and are more practically valuable than simple physicochemical indicators.
[0061] This embodiment provides a method for soil treatment of oily sludge pyrolysis residue based on screening the optimal formulation through a four-step superimposed experiment.
[0062] Step 1: Single-component experiment with mushroom residue. 1000 kg of oily sludge pyrolysis residue was taken, and different proportions of mushroom residue were added for single-factor experiments. The results showed that as the proportion of mushroom residue increased, the organic carbon content in the soil gradually increased, and the germination rates of *Lysimachia christinae* and ryegrass remained stable within the range of 38%–52%. Comparative analysis determined that the suitable addition ratio of mushroom residue was 40%–50%.
[0063] Step 2: Experiment with the combination of mushroom residue and humic acid. Based on the mushroom residue addition ratio determined in Step 1, humic acid was added to conduct a combination experiment. The suitable humic acid addition range for *Ilex cornuta* is 2%~3%, and for ryegrass, it is 1%~2%. The improvement effect was significantly enhanced after the combination, with significant improvements in plant germination rate and growth.
[0064] Step 3: Experiment with a ternary compound of inoculum residue, humic acid, and vermiculite. Adding vermiculite to the aforementioned compound further reduced the bulk density of the experimental soil, reaching a minimum of 0.77 g / cm³ in the *Ilex cornuta* group and 0.62 g / cm³ in the ryegrass group. The porous structure of vermiculite effectively adsorbed salt ions, reducing the water-soluble salt content in the experimental soil. Its interlayer structure fixed potassium ions, significantly increasing the available potassium content in the experimental soil, reaching a maximum of 330 mg / kg in the ryegrass group. The germination rate of *Ilex cornuta* increased to 71%, and that of ryegrass reached 75%.
[0065] Step 4: Quaternary compound experiment of fungal residue + humic acid + vermiculite + straw. Straw was added to the ternary compound. When the straw content of *Ilex cornuta* was 14%, the germination rate reached 87%, and the plant height was 12.2 cm; when the straw content of ryegrass was 9%, the germination rate was 84%, and the plant height was 28.8 cm. The fiber structure of straw improved the porosity of the residue, reduced the bulk density (lowest in the *Ilex cornuta* group: 0.57 g / cm³), and in the ryegrass group: lowest: 0.41 g / cm³, promoting salt migration and further reducing the water-soluble salt content.
[0066] Through a four-step superposition optimization experiment, the optimal proportions of the compound materials for the growth and development of *Ilex cornuta* seeds were determined to be: residue: fungal residue: humic acid: vermiculite: straw = 41.7%: 36.3%: 2.5%: 6%: 14%; and the optimal proportions for the growth and development of ryegrass seeds were: residue: fungal residue: humic acid: vermiculite: straw = 47.2%: 38.5%: 1.3%: 4%: 9%. This method, by gradually superimposing different improvement materials, systematically studied the synergistic mechanism among the components, achieving precise optimization of the formulation and efficient soil utilization of oily sludge pyrolysis residue.
[0067] like Figures 2-6 As shown, the present invention provides an apparatus for the above-mentioned method of soilification of oily sludge pyrolysis residue, comprising: a fermentation tank 1; a stirring system 2, including an auger shaft 21 disposed inside the fermentation tank 1 and a drive motor disposed outside the fermentation tank 1, the surface of the auger shaft 21 being fitted with wave-shaped stirring blades 22; a heating system 3; a feeding and discharging system 4; a water feeding and discharging system 5; and a gas feeding and discharging system 6.
[0068] This invention constructs a complete device comprising a fermentation tank 1, a stirring system 2, a heating system 3, a material feeding and discharging system 4, a water feeding and discharging system 5, and a gas feeding and discharging system 6, providing an integrated equipment solution for the soil treatment of oily sludge pyrolysis residue. The organic combination of each functional system provides reliable hardware support for the industrial implementation of the soil treatment method. The configuration of the wave-shaped stirring blades 22 mounted on the surface of the auger shaft 21 in the stirring system 2 and the external drive motor enables efficient material mixing.
[0069] Fermentation tank 1, as the core reaction vessel, provides a stable reaction space for the mixed fermentation of oily sludge pyrolysis residue and various amendment materials, ensuring the smooth progress of the soilification process. The auger shaft 21 in the mixing system 2 is equipped with wave-shaped stirring blades 22, which, driven by a motor, enable thorough mixing of materials. The wave-shaped design enhances the shearing and dispersing effects between materials, avoiding localized material agglomeration and ensuring the uniform distribution of oily sludge pyrolysis residue, bacterial residue, humic acid, vermiculite, straw, and other amendment materials, creating favorable material contact conditions for the fermentation reaction.
[0070] Heating system 3 provides precise temperature control for the fermentation process, adjusting it according to the temperature requirements of different fermentation stages to ensure that microbial activity is in the most suitable temperature environment, thereby improving fermentation efficiency and product quality stability. Feeding and discharging system 4 simplifies the operation process for raw material input and product output, improving the operating efficiency of the equipment and meeting the convenience requirements of industrial production.
[0071] The water inlet / outlet system 5 enables precise humidity control during fermentation. It replenishes the water needed for fermentation through the inlet system and removes excess water and fermentation filtrate through the outlet system, preventing moisture buildup from affecting fermentation and ensuring a stable fermentation environment. The gas inlet / outlet system 6 provides the necessary gas exchange channels for the fermentation process, ensuring the oxygen supply required for aerobic fermentation while promptly removing waste gas generated during fermentation, maintaining a favorable gaseous environment within the fermentation chamber 1.
[0072] Through the synergistic effect of various systems, the device can effectively control key parameters such as temperature, humidity, and aeration during the fermentation process, realizing the automation and standardization of soil treatment of oily sludge pyrolysis residue, significantly improving treatment efficiency and product quality, and providing reliable technical equipment support for the large-scale resource utilization of oily sludge pyrolysis residue.
[0073] In some embodiments, the left and right sections of the auger shaft 21 are designed with opposite spiral threads, which drive the material to move in different directions.
[0074] In this invention, the left and right sections of the auger shaft 21 adopt a thread design with opposite directions of rotation. The opposite directions of rotation of the threads drive the material to move in different directions, breaking through the limitations of traditional unidirectional thread stirring. The convergence-dispersion motion mode generated by the opposite directions of rotation significantly improves the mixing effect.
[0075] Specifically, the left-side threaded section pushes material to the right, while the right-side threaded section pushes material to the left. The two material flows converge and collide in the central region of the auger shaft 21, then diffuse upwards and downwards, forming a three-dimensional mixing flow field. The opposing spiral threads work synergistically with the wave-shaped stirring blades 22, which generate strong shearing and dispersing effects in the material convergence area, further enhancing the mixing effect. This design eliminates the mixing dead zones that are common in traditional stirring, ensuring full contact and reaction of all components.
[0076] In some embodiments, a base 7 is also included, and the fermentation box 1 is rotatably mounted on the base 7.
[0077] In this invention, the fermentation tank 1 is rotatably mounted on the base 7, which changes the discharge method of traditional fixed fermentation equipment. Traditional fixed fermentation equipment requires additional mechanical devices or manual digging to discharge materials, while the rotatable design allows the entire fermentation tank 1 to be rotated directly after fermentation to achieve gravity discharge, greatly simplifying the discharge operation process.
[0078] Specifically, the base 7 adopts a rotating support structure, and a limit knob 71 is installed on the base 7 to lock the fermentation tank 1, ensuring the stability of the fermentation tank 1 during operation. After fermentation is complete, the operator only needs to activate the rotating device to tilt the fermentation tank 1 to a suitable angle, and the fermented product will flow out naturally under gravity. This design is particularly suitable for processing viscous materials, avoiding problems such as material sticking to the walls and incomplete discharge in traditional discharge methods. The rotatable design also facilitates cleaning and maintenance of the equipment's interior.
[0079] In some embodiments, the heating system 3 includes a heating wire assembly embedded in the shaft of the auger shaft 21.
[0080] In this invention, the heating system 3 includes an electric heating wire assembly embedded in the core of the auger shaft 21, integrating heating and stirring functions into one unit. The electric heating wire is located inside the auger shaft 21, and heat is evenly diffused from the inside of the material to the outside through the heat conduction of the shaft, avoiding the problems of local overheating and excessive temperature gradient that are easily caused by external heating.
[0081] Specifically, the heating wire assembly is embedded in the hollow structure of the auger shaft 21. Heat is transferred to the shaft surface through the excellent thermal conductivity of the shaft metal, and then conducted throughout the fermentation process through the contact between the stirring blades and the material. This built-in heating method ensures more even heat distribution, and combined with the continuous stirring action of the auger shaft 21, achieves efficient heat transfer and temperature control. The power of the heating wire can be adjusted according to the temperature requirements of each fermentation stage.
[0082] In this embodiment of the invention, the built-in heating system 3 provides heat from within the material, and combined with stirring, achieves truly uniform heating, eliminating temperature dead zones and overheated areas. This technology not only improves heating efficiency and temperature control accuracy but also avoids the adverse effects of localized high temperatures on the fermentation process, providing reliable temperature control assurance for the stable production of high-quality soil-based products.
[0083] In some embodiments, the water inlet and outlet system 5 includes a sprayer 51 disposed on the top of the fermentation tank 1 and a water baffle plate 52 and a water tank 53 disposed on the bottom of the fermentation tank 1. The water baffle plate 52 has filter holes, and the water tank 53 is provided with a drain valve 54.
[0084] In this invention, the water inlet and outlet system 5 includes a sprayer 51 installed at the top of the fermentation tank 1 and a water-separating plate 52 and a water tank 53 installed at the bottom of the fermentation tank 1. The water-separating plate 52 has filter holes, and the water tank 53 is equipped with a drain valve 54. Through the cooperation of upper water supply and lower drainage, a complete water balance regulation mechanism is established.
[0085] Specifically, the top sprayer 51 can evenly spray water onto the material surface in a mist form, avoiding localized over-wetting and material structure damage caused by direct water injection. The filter hole design of the bottom baffle plate 52 allows excess water to permeate and settle while preventing solid particles from being lost, thus achieving solid-liquid separation. The water tank 53 collects the permeated water, preventing anaerobic environments caused by water accumulation and providing the possibility for water recycling. The drain valve 54 facilitates the timely discharge of excess water, maintaining a suitable moisture content range.
[0086] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.
[0087] 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 foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A method for converting oily sludge pyrolysis residue into soil, characterized in that, Includes the following steps: Raw material preparation: Mix 40-50 parts of oily sludge pyrolysis residue, 35-40 parts of fungal residue, 4-10 parts of vermiculite, 9-15 parts of straw, and 1-3 parts of humic acid by weight. Fermentation treatment: The prepared raw materials are composted and fermented, with the fermentation temperature controlled at 30℃ to 60℃, the material moisture content at 55-65%, and the fermentation time at 20-90 days. Intermittent stirring and aeration are carried out during the fermentation process. Obtain soil-based products from the pyrolysis residue of oily sludge.
2. The method for converting oily sludge pyrolysis residue into soil according to claim 1, characterized in that, The weight proportions of each component in the raw material formulation are as follows: 41.7-47.2 parts of oily sludge pyrolysis residue, 36.3-38.5 parts of fungal residue, 1.3-2.5 parts of humic acid, 4-6 parts of vermiculite, and 9-14 parts of straw.
3. The method for converting oily sludge pyrolysis residue into soil according to claim 1, characterized in that, The fermentation process includes: The first phase involves maintaining a temperature of 45-55℃ for 15-25 days. The second phase involves maintaining the temperature between 35-45℃ for 15-65 days.
4. The method for converting oily sludge pyrolysis residue into soil according to claim 3, characterized in that, The mixing interval for the first stage is 1-2 hours, and the mixing interval for the second stage is 4-6 hours.
5. The method for converting oily sludge pyrolysis residue into soil according to claim 1, characterized in that, The intermittent stirring adopts an alternating forward and reverse stirring method, with each stirring time lasting 10-30 minutes.
6. The method for converting oily sludge pyrolysis residue into soil according to claim 1, characterized in that, Before the fermentation process, the pH of the mixed raw materials is adjusted by adding quicklime or potassium dihydrogen phosphate to control the pH value within the range of 6.5-7.
5.
7. The method for converting oily sludge pyrolysis residue into soil according to claim 1, characterized in that, Temperature and humidity sensors are installed during fermentation to monitor the material temperature and moisture content in real time, and the aeration rate and water replenishment are adjusted according to the monitoring results.
8. The method for converting oily sludge pyrolysis residue into soil according to claim 1, characterized in that, The ratio of the raw materials was determined through a four-step superimposed experiment: a single-component experiment of mushroom residue, a combined experiment of mushroom residue and humic acid, a combined experiment of mushroom residue, humic acid and vermiculite, and a combined experiment of mushroom residue, humic acid, vermiculite and straw were carried out in sequence, and the optimal ratio was determined with plant germination rate and plant height as evaluation indicators.
9. An apparatus for use in the soilification method of oily sludge pyrolysis residue as described in any one of claims 1-8, characterized in that, include: Fermentation chamber (1); The stirring system (2) includes an auger shaft (21) installed inside the fermentation tank (1) and a drive motor installed outside the fermentation tank (1). The surface of the auger shaft (21) is fitted with wave-shaped stirring blades (22). Heating system (3); Feeding and discharging system (4); Water inlet and outlet system (5); Air intake and exhaust system (6).
10. The soil conversion device for oily sludge pyrolysis residue according to claim 9, characterized in that, The left and right sections of the auger shaft (21) are designed with opposite spiral threads, which drive the material to move in different directions.