Multi-stage sludge drying system and drying method

Abstract

The invention relates to the field of sludge drying, in particular to a multi-stage sludge drying system and method, and the system comprises a data collection unit for collecting sludge drying data; the parameter adjusting unit is used for adjusting the drying duration or the drying initial temperature according to the output stability coefficient of the target gas; the primary adjusting unit is used for determining whether to adjust the set temperature quantity according to the effective difference value according to the sludge discharge amount uniformity and the sludge water content uniformity of the second-stage sludge; under the condition of setting temperature quantity regulation instability, determining a secondary regulation unit for regulating the first-section rotating speed or performing heat preservation area setting analysis according to the second-section sludge abnormity degree; the heat preservation area setting unit is used for determining the setting of a single heat preservation area or multiple heat preservation areas according to the sludge particle size reference value in the heat preservation area setting analysis; and a multi-section drying unit. The sludge drying device can improve the sludge drying effect.

Description

Technical Field

[0001] The present invention relates to the field of sludge drying, and in particular to a multi-stage sludge drying system and a drying method. Background Art

[0002] As the scale of sewage treatment continues to expand, sludge treatment and disposal has become a key bottleneck restricting the development of urban sewage treatment. Currently, sludge treatment faces numerous challenges, particularly in the sludge drying process. Poor drying efficiency makes it difficult to achieve sludge reduction and stabilization goals. Furthermore, sludge treatment consumes a high amount of energy, increasing operating costs and resource consumption. Therefore, improving sludge drying efficiency is a pressing issue for those skilled in the art.

[0003] Chinese Patent Publication No. CN117534288A discloses a two-stage superheated steam drying system, comprising: a preheating section, a drying section, and a condensate collection device. The drying section receives preheated wet sludge after treatment in the preheating section, performs secondary superheated steam drying on the preheated wet sludge, and transfers the dried sludge to the preheating section. The preheating section includes a first conveyor mesh belt for receiving the wet sludge, a second conveyor mesh belt for receiving the dried sludge, and multiple condensers and dry cold air outlets located below the second conveyor mesh belt. The first conveyor mesh belt is located above the second conveyor mesh belt, and the dry cold air outlets are located below the multiple condensers so that the dry cold air sequentially exchanges heat with the condensate in the condensers and the dried sludge on the second conveyor mesh belt. The drying section is also connected to the condensate collection device, which collects the condensate in the drying section and transfers it to the condensers. However, the above solution has the following problems: it cannot dynamically adjust the drying parameters according to the drying process, and its flexibility and adaptability are relatively insufficient, resulting in poor sludge drying effect. Summary of the Invention

[0004] To this end, the present invention provides a multi-stage sludge drying system and drying method to overcome the problem in the prior art that the drying parameters cannot be dynamically adjusted according to the drying process, the flexibility and adaptability are relatively insufficient, and the sludge drying effect is poor.

[0005] To achieve the above objectives, the present invention provides a multi-stage sludge drying system, comprising:

[0006] Data acquisition unit, used to collect sludge drying data;

[0007] a parameter adjustment unit connected to the data acquisition unit, for adjusting the drying time or the initial drying temperature according to the output stability coefficient of the target gas;

[0008] A primary adjustment unit, which is connected to the data acquisition unit and the parameter adjustment unit respectively, and is used to determine whether to adjust the set temperature quantity according to the effective difference based on the sludge discharge uniformity and the sludge moisture content uniformity of the second-stage sludge;

[0009] A secondary regulating unit is connected to the primary regulating unit, and when the temperature quantity regulation is unstable, it determines whether to adjust the speed of the first stage or perform the insulation area setting analysis according to the abnormality of the second stage sludge;

[0010] A heat preservation area setting unit, which is connected to the secondary adjustment unit and is used to determine whether to set a single heat preservation area or multiple heat preservation areas according to the sludge particle size reference value in the heat preservation area setting analysis;

[0011] A multi-stage drying unit, which is respectively connected to the data acquisition unit, the parameter adjustment unit, the primary adjustment unit, the secondary adjustment unit and the insulation point setting unit, includes a horizontal thin-layer drying module for performing one-stage drying of the sludge and a linear drying module connected to the horizontal thin-layer drying module for performing two-stage drying.

[0012] Furthermore, the target gas confirmation method includes:

[0013] The gas output state is determined according to a rotation speed and a thin layer thickness reference value, and the gas reliability is determined according to the gas output state, and the gas with a reliability greater than a preset reliability is recorded as the target gas.

[0014] Furthermore, the parameter adjustment unit adjusts the drying time or the initial drying temperature according to the output stability coefficient of the target gas, including:

[0015] If the output stability coefficient of the target gas is greater than the preset output stability coefficient, the drying time is adjusted;

[0016] If the output stability coefficient of the target gas is less than or equal to the preset output stability coefficient, the drying initial temperature is adjusted.

[0017] Furthermore, when the parameter adjustment unit adjusts the drying time, the stability coefficient difference is calculated based on the output stability coefficient and the preset output stability coefficient, and the drying time is determined based on the stability coefficient difference;

[0018] The drying time is positively correlated with the difference in stability coefficient.

[0019] Furthermore, when the parameter adjustment unit adjusts the initial drying temperature, the initial drying temperature is determined according to the gas output value;

[0020] The initial drying temperature is positively correlated with the gas output value.

[0021] Furthermore, when the sludge discharge uniformity of the second-stage sludge is less than the preset sludge discharge uniformity or the sludge moisture content uniformity is less than the preset sludge moisture content uniformity, the primary adjustment unit increases the set temperature according to the effective difference:

[0022] The increase value of the set temperature quantity is positively correlated with the effective difference.

[0023] Furthermore, the secondary adjustment unit determines to adjust the first stage speed or perform insulation area setting analysis according to the abnormality of the second stage sludge, including:

[0024] If the abnormality of the second stage sludge is less than the preset abnormality of the second stage sludge, the speed of the first stage is reduced according to the abnormality of the second stage sludge;

[0025] If the abnormality of the second stage sludge is greater than or equal to the preset abnormality of the second stage sludge, the insulation area setting analysis is performed;

[0026] The reduction value of the first stage rotation speed is positively correlated with the abnormality of the second stage sludge.

[0027] Furthermore, the heat preservation area setting unit performs multi-heat preservation area setting when the sludge particle size reference value is greater than or equal to the preset sludge particle size reference value;

[0028] In the multi-insulation zone setting, the insulation zone is set according to the regional abnormality and the calorific value variation coefficient, and under the preset abnormal conditions, the temperature of each insulation zone is increased and adjusted according to the variation coefficient;

[0029] The temperature increase corresponding to a single insulation area is positively correlated with the coefficient of variation corresponding to the insulation area.

[0030] Furthermore, the heat preservation area setting unit performs single heat preservation area setting when the sludge particle size reference value is less than the preset sludge particle size reference value;

[0031] In the single insulation area setting, the insulation surface distance corresponding to the insulation area is determined according to the coking coefficient, and the insulation surface distance is negatively correlated with the coking coefficient.

[0032] The present invention also provides a multi-stage sludge drying method, comprising:

[0033] Collect sludge drying data;

[0034] Adjust the drying time or initial drying temperature according to the output stability coefficient of the target gas;

[0035] Determine whether to adjust the set temperature quantity according to the effective difference based on the uniformity of the sludge discharge volume and the uniformity of the sludge moisture content of the second stage sludge;

[0036] Under the condition of temperature quantity regulation instability, adjust the speed of the first stage or analyze the setting of the insulation area according to the abnormality of the second stage sludge;

[0037] In the insulation area setting analysis, the single insulation area or multiple insulation area setting is determined based on the sludge particle size reference value.

[0038] Compared with the prior art, the beneficial effect of the present invention lies in that, in the technical solution of the present invention, the output stability coefficient can reflect the stability of gas output during the drying process in real time, and then the drying time or initial temperature can be adjusted in a targeted manner according to the gas output stability coefficient, so that the drying process can be closely fitted with the actual drying requirements of the sludge. When the output stability coefficient is high, the drying time is appropriately extended to ensure that the sludge fully loses water in a stable drying environment and reaches the expected degree of drying; and when the output stability coefficient is low, the drying rate can be quickly changed by adjusting the initial temperature, so that the drying process can better adapt to the changes in the characteristics of the sludge, thereby improving the consistency of the drying effect and ensuring the stability of the sludge quality after drying.

[0039] Furthermore, in the present invention, the stability of the sludge drying process and the drying effect are effectively reflected by the sludge discharge uniformity and the water content uniformity, and then the sludge discharge uniformity and the sludge water content uniformity of the second-stage sludge are used to determine whether to adjust the set temperature quantity according to the effective difference. By increasing the set temperature quantity, the temperature gradient in the drying process can be more accurately controlled to ensure that the sludge can obtain appropriate heat supply in different drying stages, thereby improving the uniformity of the drying effect and the quality of the dried sludge.

[0040] Furthermore, in the present invention, the degree of deviation of the sludge from the normal state during the drying process is reflected by the second-stage sludge abnormality. When the second-stage sludge abnormality is less than the preset second-stage sludge abnormality, it indicates that the drying process is relatively stable. At this time, reducing the first-stage rotation speed can extend the residence time of the sludge in the drying equipment, further ensuring the uniformity and stability of the drying effect; and when the second-stage sludge abnormality is greater than or equal to the preset second-stage sludge abnormality, it means that the drying process may have large fluctuations. At this time, performing an insulation area setting analysis can improve the temperature distribution in the drying equipment, so that the sludge can be dried under suitable temperature conditions, thereby improving the sludge drying effect.

[0041] Furthermore, the present invention uses a single or multiple insulation zone configuration based on the sludge particle size reference value, which is more in line with actual application scenarios. The multiple insulation zone configuration, combined with the regional anomaly and calorific value variation coefficient, can provide precise insulation conditions for sludge in different regions, fully accounting for local differences, optimizing the drying effect, and achieving accurate and timely temperature compensation, effectively improving the drying effect and avoiding localized insufficient or excessive drying. In the single insulation zone configuration, the insulation surface distance is positively correlated with the coking coefficient, enabling precise energy management, highly matching energy input with drying requirements, and further optimizing energy utilization efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is a unit connection diagram of the multi-stage sludge drying system of the present invention;

[0043] Figure 2 This is a flow chart of adjusting the drying time or the initial drying temperature according to the output stability coefficient of the target gas according to the present invention;

[0044] Figure 3 This is a flow chart of the present invention for determining whether to adjust the sludge drying temperature range according to the effective difference based on the sludge discharge uniformity and the sludge moisture content uniformity of the second-stage sludge;

[0045] Figure 4 This is a schematic structural diagram of the horizontal thin layer drying module of the present invention;

[0046] In the figure: drying shell 1, feed port 2, jacket 3, heat transfer oil pipe 4, gas outlet 5, movable partition 6, hollow shaft 7, blades 8, discharge port 9;

[0047] Figure 5 Schematic diagram of the multi-stage sludge drying method of the present invention. DETAILED DESCRIPTION

[0048] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are merely used to explain the present invention and are not intended to limit the present invention.

[0049] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0050] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "inside", and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0051] See also Figures 1 to 3 As shown, the present invention provides a multi-stage sludge drying system, comprising:

[0052] Data acquisition unit, used to collect sludge drying data;

[0053] a parameter adjustment unit connected to the data acquisition unit, for adjusting the drying time or the initial drying temperature according to the output stability coefficient of the target gas;

[0054] A primary adjustment unit, which is connected to the data acquisition unit and the parameter adjustment unit respectively, and is used to determine whether to adjust the set temperature quantity according to the effective difference based on the sludge discharge uniformity and the sludge moisture content uniformity of the second-stage sludge;

[0055] A secondary regulating unit is connected to the primary regulating unit, and when the temperature quantity regulation is unstable, it determines whether to adjust the speed of the first stage or perform the insulation area setting analysis according to the abnormality of the second stage sludge;

[0056] A heat preservation area setting unit, which is connected to the secondary adjustment unit and is used to determine whether to set a single heat preservation area or multiple heat preservation areas according to the sludge particle size reference value in the heat preservation area setting analysis;

[0057] A multi-stage drying unit, which is respectively connected to the data acquisition unit, the parameter adjustment unit, the primary adjustment unit, the secondary adjustment unit and the insulation point setting unit, includes a horizontal thin-layer drying module for performing one-stage drying of the sludge and a linear drying module connected to the horizontal thin-layer drying module for performing two-stage drying.

[0058] The application scenario of the present invention is sludge drying treatment. In the present invention, several historical records are correspondingly provided. Any historical record records a first-stage rotation speed, a thin layer thickness reference value, a reliability, an output stability coefficient, and a second-stage sludge abnormality, etc. in the historical process of at least one sludge drying treatment. Each historical record corresponds to a qualified mark, which records whether the sludge drying treatment process meets the user's requirements. The qualified mark can be recorded manually. It is understandable that the user can determine whether the sludge drying treatment process meets the requirements based on self-set indicators. The self-set indicators can be but are not limited to dehydration rate, which will not be described in detail here. Dehydration rate = weight of sludge after drying treatment / weight of sludge before drying treatment;

[0059] The present invention is provided with a target coefficient and a related threshold value, and the corresponding relationship between the target coefficient and the related threshold value is expressed by a weight formula, and the weight formula is: target coefficient = weight coefficient × related threshold value. Specifically, the present invention records the value of n, the drying time, the initial drying temperature, the increase in the number of set temperatures, the decrease in the speed of one stage, the increase in the temperature corresponding to the insulation area, and the insulation surface distance as the target coefficient, and records the temperature interval length, the stability coefficient difference, the gas output value, the effective difference, the abnormality of the second stage sludge, the coefficient of variation, and the coking coefficient as the related threshold value. It can be understood that the target coefficients all have corresponding relationships. Related thresholds, for example, the value of n is positively correlated with the length of the temperature interval, and the positive correlation between the value of n and the length of the temperature interval is expressed by a weight formula. The value of the weight coefficient can be determined by the user's historical experience according to the degree of influence of the temperature interval length on the value of n, and the value of the weight coefficient can be optimized by combining the historical records of multiple sludge drying processes with a multi-layer perceptron. The use of a multi-layer perceptron to optimize the value of the weight coefficient is easy for those skilled in the art to understand, and will not be described in detail. The principles for determining the values ​​of the weight coefficients corresponding to other target coefficients and related thresholds are the same, and will not be described in detail here.

[0060] The instability condition of the set temperature quantity adjustment is that after the set temperature quantity is adjusted according to the effective difference, the sludge discharge uniformity of the second stage sludge is less than the preset sludge discharge uniformity or the sludge moisture content uniformity is less than the preset sludge moisture content uniformity;

[0061] The sludge drying data includes but is not limited to the thickness of the sludge thin layer, the sludge discharge volume of the second-stage sludge, the volume of the target gas discharged from the air outlet of the horizontal thin layer drying module, and the sludge moisture content of the second-stage sludge. The thickness of the sludge thin layer is measured by an ultrasonic sensor, the volume of the target gas discharged from the air outlet of the horizontal thin layer drying module is measured by a gas flow sensor, and the sludge discharge volume of the second-stage sludge is measured by a weighing sensor. This is content that is easy for technical personnel in this field to understand and will not be elaborated on.

[0062] Specifically, the target gas confirmation method includes:

[0063] The gas output state is determined according to a rotation speed and a thin layer thickness reference value, and the gas reliability is determined according to the gas output state, and the gas with a reliability greater than a preset reliability is recorded as the target gas.

[0064] If the speed of a section is greater than or equal to the preset speed of a section and the thin layer thickness reference value is less than the preset thin layer thickness reference value, the gas output state is stable. At this time, the reliability of the gas is the standard deviation of the evaluation coefficient corresponding to each time point in the preset time period;

[0065] If the speed of a section is less than the preset speed of a section or the thin layer thickness reference value is greater than or equal to the preset thin layer thickness reference value, the gas production state is unstable, and the gas reliability is recorded as 0.

[0066] The gas is the gas discharged from the gas outlet of the horizontal thin layer drying module after the initial moment of the preset time period;

[0067] The preset time period is the time period selected by the user after the multi-stage drying unit starts working according to the initial working process. The value of the preset time period can be determined by the user according to the actual application scenario. The greater the user's demand for improving the reliability of the target gas, the longer the value of the preset time period is. A preset time period value is provided, and the preset time period is 20 minutes;

[0068] Taking the initial moment of the preset time period as the starting point, set an interval point every 1 minute until the preset time is reached, and record the starting point and each interval point as the time point;

[0069] Initial work process, including:

[0070] (1) One-stage drying: wet sludge enters the horizontal thin-layer drying module from the feed port of the horizontal thin-layer drying module. The motor drives the hollow shaft to rotate at a speed of 100 rpm. The drying area of ​​the horizontal thin-layer drying module is a cylinder. The cylindrical drying area is divided into three equal parts along its length to obtain three sub-areas. The initial drying temperature range is [80°C, 120°C]. The corresponding temperatures of each sub-area are 80°C, 100°C, and 120°C in the order from near to far from the feed port of the horizontal thin-layer drying module. The heat transfer oil pipe Heat transfer oil of corresponding temperature is injected into the jacket corresponding to each sub-area. The jacket is equipped with multiple movable partitions made of heat-resistant stainless steel. With the help of a motor-driven screw, the partitions can be flexibly moved in the jacket, thereby flexibly dividing the jacket space to achieve precise temperature control in different areas. The blades evenly spread the sludge on the surface of the hot wall to form a thin sludge layer. Heat is transferred to the sludge layer through heat conduction. The duration of the horizontal thin layer drying module is 15 minutes. The gas generated by the evaporation of water in the sludge is discharged through the outlet. The dried sludge is discharged through the discharge port.

[0071] (2) Second stage drying: The sludge discharged from the outlet of the horizontal thin layer drying module enters the linear drying module and is evenly distributed by the scraper conveyor. The sludge is further dried for 1 hour and then discharged from the outlet of the linear drying module.

[0072] The first speed is the speed of rotation of the hollow shaft in the horizontal thin layer drying module, and the first speed is 100rmp.

[0073] The reference value of the thin layer thickness is the average value of the thickness of the sludge thin layer corresponding to each sampling point collected at the earliest time point of the preset period. The sampling points are several points randomly selected in the drying area of ​​the horizontal thin layer drying module. The positions of the sampling points are different. There is no restriction on the specific selection position of each sampling point and the user can select it. The number of sampling points is 10. The thickness of the sludge thin layer corresponding to a single sampling point is measured by an ultrasonic sensor. In addition, the content that is easy for those skilled in the art to understand is not described in detail.

[0074] The values ​​of the preset speed section and the preset thin layer thickness reference value can be determined by the user according to the actual application scenario. The greater the user's demand for improving the reliability of the target gas, the greater the value of the preset speed section and the smaller the value of the preset thin layer thickness reference value. Provided are the values ​​of the preset speed section and the preset thin layer thickness reference value. The average value of the speed section and the average value of the thin layer thickness reference value corresponding to each historical record in which the output state of the detected gas is stable and can meet the user's needs are recorded as the preset speed section and the preset thin layer thickness reference value respectively.

[0075] The reliability of the gas is the average value of the evaluation coefficients corresponding to each time point within the preset time period. The evaluation coefficient corresponding to a single time point = a speed section / a preset speed section - the average value of the thickness of the sludge layer corresponding to each sampling point collected at that time point / the preset thin layer thickness reference value;

[0076] The value of the preset reliability can be determined by the user according to the actual application scenario. The greater the user's demand for improving the gas reliability, the larger the value of the preset reliability is. A method for determining the value of the preset reliability is provided, and the average value of the reliability corresponding to each historical record of the target gas that can meet the user's needs is recorded as the preset reliability.

[0077] Specifically, the parameter adjustment unit adjusts the drying time or the initial drying temperature according to the output stability coefficient of the target gas, including:

[0078] If the output stability coefficient of the target gas is greater than the preset output stability coefficient, the drying time is adjusted;

[0079] If the output stability coefficient of the target gas is less than or equal to the preset output stability coefficient, the drying initial temperature is adjusted.

[0080] Among them, the output stability coefficient = 1 / (the standard deviation of the evaluation coefficient corresponding to each time point within the preset time period + 1);

[0081] The value of the preset output stability coefficient can be determined by the user according to the actual application scenario. The smaller the value of the preset output stability coefficient, the greater the user's need to adjust the drying time. A method for determining the value of the preset output stability coefficient is provided. The historical records of adjustment of the drying time are detected, and the average value of the output stability coefficients corresponding to the historical records that can meet the user's needs is recorded as the preset output stability coefficient.

[0082] Drying time refers to the length of time the drying process is carried out in the horizontal thin layer drying module;

[0083] The initial drying temperature is the initial temperature of the drying temperature range of the horizontal thin layer drying module;

[0084] The horizontal thin layer drying module corresponds to a drying temperature interval, which is [drying initial temperature, drying end temperature], and the drying end temperature is 120°C. The drying temperature interval is divided into n equal parts, and the temperatures corresponding to each dividing point, as well as the drying initial temperature and drying end temperature, are all recorded as set temperatures. The value of n is positively correlated with the length of the temperature interval, and the temperature interval length = drying end temperature - drying initial temperature. The drying area of ​​the horizontal thin layer drying module is a cylinder. This cylindrical drying area is divided into (n+1) equal parts along its length to obtain (n+2) sub-areas. Each sub-area also has a cylindrical shape, and the bottom areas of all these sub-areas are equal. Each sub-area corresponds to a set temperature. The set temperature corresponding to the sub-area closest to the feed inlet of the horizontal thin layer drying module is the lowest, and as the distance from the sub-area to the feed inlet increases, the set temperature corresponding to the sub-area gradually increases.

[0085] It is understandable that when the output stability coefficient is greater than the preset output stability coefficient, it means that the current drying process is in a relatively stable state. In this case, the main goal of the drying system is to further consolidate and utilize this stable drying condition and remove moisture from the sludge as fully as possible to achieve the expected drying effect. By extending the drying time, the sludge can be continuously heated in a stable drying environment, thereby improving the quality of the dried sludge and ensuring the uniformity and stability of the drying effect.

[0086] When the output stability coefficient is less than or equal to the preset output stability coefficient, the stability of the drying process is relatively poor. In this case, the drying process is strengthened by adjusting the initial drying temperature, so that the drying process can enter the high-efficiency stage faster, which helps to reduce unnecessary losses caused by the instability of the drying process.

[0087] Specifically, when the parameter adjustment unit adjusts the drying time, it calculates the stability coefficient difference based on the output stability coefficient and the preset output stability coefficient, and determines the drying time based on the stability coefficient difference;

[0088] The drying time is positively correlated with the difference in stability coefficient.

[0089] Among them, the stability coefficient difference is calculated based on the output stability coefficient and the preset output stability coefficient.

[0090] Stability coefficient difference = preset output stability coefficient - output stability coefficient.

[0091] Specifically, when the parameter adjustment unit adjusts the initial drying temperature, the initial drying temperature is determined according to the gas output value;

[0092] The initial drying temperature is positively correlated with the gas output value.

[0093] The gas output value is the volume of target gas discharged from the outlet of the horizontal thin layer drying module per unit time, and the unit is m 3 / h.

[0094] It can be understood that the gas output value reflects the water evaporation rate during the drying process. By monitoring the gas output value, the drying efficiency can be reflected in real time. When the output value deviates from the target range, appropriate adjustment of the initial temperature can optimize the drying effect and energy consumption, ensuring that the sludge is efficiently dried at the optimal temperature and improving the performance and adaptability of the drying system.

[0095] Specifically, when the sludge discharge uniformity of the second-stage sludge is less than the preset sludge discharge uniformity or the sludge moisture content uniformity is less than the preset sludge moisture content uniformity, the primary adjustment unit increases the set temperature according to the effective difference:

[0096] The increase in the number of set temperatures is positively correlated with the effective difference.

[0097] The time when the sludge is discharged from the linear drying module after the drying time is determined according to the difference in the stability coefficient and the initial drying temperature is determined according to the gas output value is recorded as the starting monitoring point. An interval monitoring point is set every 10 minutes until the number of interval monitoring points set is 5. The starting monitoring point and each interval monitoring point are recorded as monitoring points, and the time between two adjacent monitoring points is recorded as a monitoring period.

[0098] Sludge discharge uniformity = 1 / (standard deviation of sludge discharge corresponding to each monitoring period + 1). The sludge discharge corresponding to a single monitoring period is the total amount of sludge discharged from the discharge port of the linear drying module during the monitoring period, in kg.

[0099] Sludge moisture uniformity = 1 / (standard deviation of sludge moisture content corresponding to each monitoring period + 1), sludge moisture content corresponding to a single monitoring period = 1-M / 500. Randomly weigh 500 g of sludge discharged from the discharge port of the linear drying module during the monitoring period, place the sludge in an oven, and continue heating at 105°C until its mass no longer changes and reaches a constant weight. Record the sludge mass after reaching constant weight, which is recorded as Mg;

[0100] The values ​​of the preset sludge discharge volume uniformity and the preset sludge moisture content uniformity can be determined by the user according to the actual application scenario. The larger the values ​​of the preset sludge discharge volume uniformity and the preset sludge moisture content uniformity, the greater the user's demand for increasing the set temperature quantity according to the effective difference. A preset sludge discharge volume uniformity and a preset sludge moisture content uniformity value are provided, and the historical records of the user increasing the set temperature quantity according to the effective difference are detected. The average values ​​of the sludge discharge volume uniformity and the average values ​​of the sludge moisture content uniformity corresponding to the historical records that can meet the user's needs are recorded as the preset sludge discharge volume uniformity and the preset sludge moisture content uniformity, respectively.

[0101] The number of set temperatures is the total number of set temperatures. It can be understood that the initial number of set temperatures is n+2;

[0102] Effective difference = Second stage sludge abnormality - average value of second stage sludge abnormality corresponding to historical records that can meet user needs. It should be noted that when determining the effective difference based on the second stage sludge abnormality, the second stage sludge abnormality needs to be determined by the sludge discharge uniformity and the sludge moisture content uniformity. The monitoring period involved at this time is the time when the sludge is discharged from the linear drying module after the drying time is determined based on the stability coefficient difference and the initial drying temperature is determined based on the gas output value. The monitoring period is recorded as the starting monitoring point.

[0103] It is understood that the number of set temperatures is the same as the number of sub-regions, and when the number of set temperatures is increased, the increase value of the set temperature number is the same as the increase value of the sub-region number;

[0104] It should be noted that if the sludge discharge uniformity of the second-stage sludge is greater than or equal to the preset sludge discharge uniformity and the sludge moisture content uniformity is greater than or equal to the preset sludge moisture content uniformity, there is no need to adjust the set temperature quantity according to the effective difference.

[0105] It can be understood that when the sludge discharge uniformity of the second-stage sludge is less than the preset sludge discharge uniformity or the sludge moisture content uniformity is less than the preset sludge moisture content uniformity, it indicates that the drying process is unstable. Increasing the set temperature number according to the effective difference can enhance the heat transfer of the drying process and improve the sludge drying effect. Increasing and adjusting the set temperature number according to the effective difference can improve the stability and uniformity of the drying effect.

[0106] Specifically, the secondary adjustment unit determines to adjust the speed of the first stage or perform an analysis on the setting of the insulation area according to the abnormality of the second stage sludge, including:

[0107] If the abnormality of the second stage sludge is less than the preset abnormality of the second stage sludge, the speed of the first stage is reduced according to the abnormality of the second stage sludge;

[0108] If the abnormality of the second stage sludge is greater than or equal to the preset abnormality of the second stage sludge, the insulation area setting analysis is performed;

[0109] The reduction value of the first stage rotation speed is positively correlated with the abnormality of the second stage sludge.

[0110] Among them, the second-stage sludge abnormality = - sludge discharge uniformity / preset sludge discharge uniformity + sludge moisture uniformity / preset sludge moisture uniformity); it should be noted that when determining the second-stage sludge abnormality based on the sludge discharge uniformity and sludge moisture uniformity, the monitoring period involved is the first monitoring period determined by the first starting monitoring point, when the set temperature is increased according to the effective difference and the sludge discharge starts from the linear drying module;

[0111] The moment when the sludge is discharged from the linear drying module after the set temperature number is increased and adjusted according to the effective difference is recorded as the first starting monitoring point. A first interval monitoring point is set every 10 minutes until the number of set first interval monitoring points is 5. The first starting monitoring point and each first interval monitoring point are recorded as the first monitoring point, and the time between two adjacent first monitoring points is recorded as a first monitoring period.

[0112] The value of the preset second-stage sludge abnormality degree can be determined by the user according to the actual application scenario. The smaller the value of the preset second-stage sludge abnormality degree, the greater the user's need for insulation area setting analysis. A method for determining the value of the preset second-stage sludge abnormality degree is provided. The historical records of insulation area setting analysis are detected, and the average value of the second-stage sludge abnormality degree corresponding to the historical records that can meet the user's needs is recorded as the preset second-stage sludge abnormality degree.

[0113] It can be understood that when the second-stage sludge abnormality is less than the preset second-stage sludge abnormality, it indicates that the drying process is relatively stable, but there are still slight abnormalities. By reducing the first-stage rotation speed, the residence time of the sludge in the drying equipment can be increased, thereby changing the contact time and contact method between the sludge and the drying medium, so that the sludge can be more fully subjected to drying treatment, which helps to further improve the uniformity and stability of the drying effect; when the second-stage sludge abnormality is greater than or equal to the preset second-stage sludge abnormality, a comprehensive evaluation of factors such as the temperature distribution in the drying equipment and the thermal characteristics of the sludge is conducted to determine a reasonable insulation area, which is directly related to the heat distribution and transfer efficiency in the drying equipment, thereby improving the drying effect and ensuring the smooth progress of the drying process.

[0114] Specifically, the heat preservation area setting unit performs multi-heat preservation area setting when the sludge particle size reference value is greater than or equal to the preset sludge particle size reference value;

[0115] In the multi-insulation zone setting, the insulation zone is set according to the regional abnormality and the calorific value variation coefficient, and under the preset abnormal conditions, the temperature of each insulation zone is increased and adjusted according to the variation coefficient;

[0116] The temperature increase corresponding to a single insulation area is positively correlated with the coefficient of variation corresponding to the insulation area.

[0117] Among them, the sludge particle size reference value is the average value of the sub-particle size reference values ​​corresponding to each first monitoring period, and the sub-particle size reference value corresponding to a single first monitoring period is the average value of the particle sizes of several sludge particles randomly selected from the sludge discharged from the discharge port of the linear drying module during the first monitoring period. The number of sludge particles selected in a single first monitoring period is 50. The particle size of the sludge particles is measured by sieving method, and the details are not repeated here.

[0118] The value of the preset sludge particle size reference value can be determined by the user according to the actual application scenario. The larger the value of the preset sludge particle size reference value is, the greater the user's demand for setting a single insulation area. A method for determining the value of the preset sludge particle size reference value is provided, which detects the historical records of the user setting multiple insulation areas, and records the average value of the sludge particle size reference values ​​corresponding to the historical records that can meet the user's needs as the preset sludge particle size reference value;

[0119] For a single sub-region, the regional abnormality corresponding to the sub-region is the regional thin layer thickness corresponding to the sub-region - the preset regional thin layer thickness. The regional thin layer thickness corresponding to a single sub-region is the average thickness of the sludge thin layer corresponding to three randomly selected points in the sub-region after increasing the number of set temperatures according to the effective difference. The preset regional thin layer thickness is the average value of the regional thin layer thickness corresponding to each sub-region in the historical records that can meet user needs;

[0120] The calorific value variation coefficient corresponding to a single sub-region = the calorific value corresponding to the sub-region - the calorific value corresponding to the sub-region located before the sub-region. The calorific value corresponding to a single sub-region is the calorific value of the sludge in the sludge layer located in the sub-region measured by oxygen bomb calorimetry after increasing the set temperature according to the effective difference;

[0121] The sub-regions whose regional abnormality is greater than the preset regional abnormality or whose calorific value variation coefficient is greater than the preset calorific value variation coefficient are recorded as abnormal regions;

[0122] The values ​​of the preset regional abnormality and the preset calorific value variation coefficient can be determined by the user according to the actual application scenario. The greater the user's demand for improving the sludge treatment effect, the smaller the values ​​of the preset regional abnormality and the preset calorific value variation coefficient are. A value of the preset regional abnormality and the preset calorific value variation coefficient is provided, and the average value of the regional abnormality and the average value of the calorific value variation coefficient corresponding to each abnormal region in the historical records that can meet the user's needs are detected and recorded as the preset regional abnormality and the preset calorific value variation coefficient respectively;

[0123] For each abnormal area, the bottom surface of each abnormal area closer to the feed inlet of the horizontal thin-layer drying module and the bottom surface of the sub-area farthest from the feed inlet are recorded as the insulation surface. The area between two adjacent insulation surfaces is a insulation area. The temperature of a single insulation area is the average value of the set temperatures corresponding to each sub-area in the insulation area.

[0124] The preset abnormal condition is that after the insulation area is set according to the regional abnormality and the calorific value variation coefficient, the abnormality of the second-stage sludge is still greater than the preset abnormality of the second-stage sludge; the method for confirming the abnormality of the second-stage sludge after the insulation area is set according to the regional abnormality and the calorific value variation coefficient is the same as the method for confirming the abnormality of the second-stage sludge by the sludge discharge uniformity and the sludge moisture content uniformity, and the details are not repeated here;

[0125] The coefficient of variation corresponding to a single insulation area is = the average value of the regional abnormality corresponding to each sub-area in the insulation area / the average value of the regional abnormality corresponding to each sub-area in each insulation area in the historical records that can meet user needs - the second-stage sludge abnormality after setting the insulation area according to the regional abnormality and the calorific value variation coefficient / the second-stage sludge abnormality before setting the insulation area according to the regional abnormality and the calorific value variation coefficient.

[0126] Specifically, the heat preservation area setting unit performs single heat preservation area setting when the sludge particle size reference value is less than the preset sludge particle size reference value;

[0127] In the single insulation area setting, the insulation surface distance corresponding to the insulation area is determined according to the coking coefficient, and the insulation surface distance is negatively correlated with the coking coefficient.

[0128] The coking coefficient is the average value of the coking reference values ​​corresponding to each first monitoring period. The coking reference value corresponding to a single first monitoring period = the mass of coked sludge in the sludge discharged from the discharge port of the linear drying module during the first monitoring period / the sludge discharge volume corresponding to the first monitoring period.

[0129] The insulation surface distance is the distance between the first bottom surface of the insulation area and the feed inlet of the horizontal thin layer drying module. The second bottom surface is the bottom surface of the sub-area farthest from the feed inlet and is farther away from the feed inlet. The first bottom surface is parallel to the second bottom surface. The area between the two bottom surfaces is used as the insulation area. The temperature of the insulation area is the same as the set temperature corresponding to the distant sub-area where the first bottom surface is located. The distant sub-area where the first bottom surface is located is a sub-area with the first bottom surface as the bottom surface and is farther away from the feed inlet of the horizontal thin layer drying module.

[0130] See also Figure 4 As shown, it is a schematic structural diagram of the horizontal thin layer drying module of the present invention, and the horizontal thin layer drying module includes:

[0131] Drying shell 1;

[0132] A feed port 2 is connected to the outer surface of one end of the drying shell 1 in the longitudinal direction, and is used to pass the sludge into the interior of the drying shell 1;

[0133] The jacket 3 is arranged around the outer surface of the drying shell 1 and is provided with a heat transfer oil pipe 4 for introducing heat transfer oil, an outlet 5 for discharging the gas generated by heating, and a movable partition 6 for dividing the space of the jacket 3;

[0134] A hollow shaft 7 is disposed inside the drying shell 1. A plurality of blades are disposed on the surface of the hollow shaft 7. The hollow shaft is used to drive the blades 8 to rotate by rotating;

[0135] The discharge port 9 is provided on the outer surface of the drying shell 1 at one end away from the feed port 2 in the length direction, and is used to discharge the dried sludge.

[0136] See also Figure 5 As shown, it is a schematic diagram of the multi-stage sludge drying method of the present invention. The present invention also provides a multi-stage sludge drying method, comprising:

[0137] Collect sludge drying data;

[0138] Adjust the drying time or initial drying temperature according to the output stability coefficient of the target gas;

[0139] Determine whether to adjust the set temperature quantity according to the effective difference based on the uniformity of the sludge discharge volume and the uniformity of the sludge moisture content of the second stage sludge;

[0140] Under the condition of temperature quantity regulation instability, adjust the speed of the first stage or analyze the setting of the insulation area according to the abnormality of the second stage sludge;

[0141] In the insulation area setting analysis, the single insulation area or multiple insulation area setting is determined based on the sludge particle size reference value.

[0142] Thus far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present invention.

Claims

1. A multi-stage sludge drying system, characterized in that: include: Data acquisition unit, used to collect sludge drying data; a parameter adjustment unit connected to the data acquisition unit, for adjusting the drying time or the initial drying temperature according to the output stability coefficient of the target gas; A primary adjustment unit, which is connected to the data acquisition unit and the parameter adjustment unit respectively, and is used to determine whether to adjust the set temperature quantity according to the effective difference based on the sludge discharge uniformity and the sludge moisture content uniformity of the second-stage sludge; A secondary regulating unit is connected to the primary regulating unit, and when the temperature quantity regulation is unstable, it determines whether to adjust the speed of the first stage or perform the insulation area setting analysis according to the abnormality of the second stage sludge; A heat preservation area setting unit, which is connected to the secondary adjustment unit and is used to determine whether to set a single heat preservation area or multiple heat preservation areas according to the sludge particle size reference value in the heat preservation area setting analysis; A multi-stage drying unit, which is respectively connected to the data acquisition unit, the parameter adjustment unit, the primary adjustment unit, the secondary adjustment unit and the insulation point setting unit, includes a horizontal thin-layer drying module for performing one-stage drying of the sludge and a linear drying module connected to the horizontal thin-layer drying module for performing two-stage drying.

2. The multi-stage sludge drying system according to claim 1, characterized in that: The target gas confirmation method includes: The gas output state is determined according to a rotation speed and a thin layer thickness reference value, and the gas reliability is determined according to the gas output state, and the gas with a reliability greater than a preset reliability is recorded as the target gas.

3. The multi-stage sludge drying system according to claim 2, characterized in that: The parameter adjustment unit adjusts the drying time or the initial drying temperature according to the output stability coefficient of the target gas, including: If the output stability coefficient of the target gas is greater than the preset output stability coefficient, the drying time is adjusted; If the output stability coefficient of the target gas is less than or equal to the preset output stability coefficient, the drying initial temperature is adjusted.

4. The multi-stage sludge drying system according to claim 3, characterized in that: When the parameter adjustment unit adjusts the drying time, the stability coefficient difference is calculated based on the output stability coefficient and the preset output stability coefficient, and the drying time is determined based on the stability coefficient difference; The drying time is positively correlated with the difference in stability coefficient.

5. The multi-stage sludge drying system according to claim 4, characterized in that: When the parameter adjustment unit adjusts the initial drying temperature, the initial drying temperature is determined according to the gas output value; The initial drying temperature is positively correlated with the gas output value.

6. The multi-stage sludge drying system according to claim 5, characterized in that: When the sludge discharge uniformity of the second stage sludge is less than the preset sludge discharge uniformity or the sludge moisture content uniformity is less than the preset sludge moisture content uniformity, the primary adjustment unit increases the set temperature according to the effective difference: The increase value of the set temperature quantity is positively correlated with the effective difference.

7. The multi-stage sludge drying system according to claim 1, characterized in that: The secondary adjustment unit determines to adjust the speed of the first stage or perform insulation area setting analysis based on the abnormality of the second stage sludge, including: If the abnormality of the second stage sludge is less than the preset abnormality of the second stage sludge, the speed of the first stage is reduced according to the abnormality of the second stage sludge; If the abnormality of the second stage sludge is greater than or equal to the preset abnormality of the second stage sludge, the insulation area setting analysis is performed; The reduction value of the first stage rotation speed is positively correlated with the abnormality of the second stage sludge.

8. The multi-stage sludge drying system according to claim 7, characterized in that: The heat preservation area setting unit performs multiple heat preservation area setting when the sludge particle size reference value is greater than or equal to the preset sludge particle size reference value; In the multi-insulation zone setting, the insulation zone is set according to the regional abnormality and the calorific value variation coefficient, and under the preset abnormal conditions, the temperature of each insulation zone is increased and adjusted according to the variation coefficient; The temperature increase corresponding to a single insulation area is positively correlated with the coefficient of variation corresponding to the insulation area.

9. The multi-stage sludge drying system according to claim 8, characterized in that: The heat preservation area setting unit performs single heat preservation area setting when the sludge particle size reference value is less than the preset sludge particle size reference value; In the single insulation area setting, the insulation surface distance corresponding to the insulation area is determined according to the coking coefficient, and the insulation surface distance is negatively correlated with the coking coefficient.

10. A drying method using the multi-stage sludge drying system according to any one of claims 1 to 9, characterized in that: include: Collect sludge drying data; Adjust the drying time or initial drying temperature according to the output stability coefficient of the target gas; Determine whether to adjust the set temperature quantity according to the effective difference based on the uniformity of the sludge discharge volume and the uniformity of the sludge moisture content of the second stage sludge; Under the condition of temperature quantity regulation instability, adjust the speed of the first stage or analyze the setting of the insulation area according to the abnormality of the second stage sludge; In the insulation area setting analysis, the single insulation area or multiple insulation area setting is determined based on the sludge particle size reference value.

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