Sulfur autotrophic denitrification sulfur source stable supply method based on sulfur source effectiveness evaluation model

Abstract

The invention provides a sulfur autotrophic denitrification sulfur source stable supply method based on a sulfur source effectiveness evaluation model, which comprises the following steps of: calculating electrons required by nitrate and nitrite in inlet water by establishing an electron dosage standard taking electron equivalent as a core, and obtaining a theoretical sulfur electron number from sulfide, sulfur-containing salts, amines and iron in absorption liquid; constructing a correction model taking an absorption liquid index, a redox value, dissolved oxygen and a replacement interval as inputs and a single adjustment coefficient as an output, and obtaining a corrected sulfur electron number; the method comprises the following steps: under a first-calculation and second-adjustment combined band limitation scheme of setting an allowable operation range of the sulfur / nitrate electron ratio, calculating a sulfur adding flow according to a required electron number, setting a sulfur adding upper limit by combining sulfate growth and a redox value, and performing small-amplitude post-adjustment and coefficient updating according to residues of nitrate and nitrite in effluent. Nitrate leakage is avoided, excessive sulfate is inhibited, the corrosion risk is reduced, and stable supply is achieved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of sulfur autotrophic denitrification control in sewage treatment, and particularly relates to a sulfur autotrophic denitrification sulfur source stable supply method based on a sulfur source effectiveness evaluation model. BACKGROUND

[0002] Sulfur autotrophic denitrification takes sulfide, thiosulfate and other reducing sulfur compounds as electron donors to reduce nitrate and nitrite, and is often used for advanced treatment of high-nitrate wastewater and groundwater remediation. In engineering, sulfur is usually added according to electron equivalent or stoichiometry, but due to the influence of changes in absorption liquid composition, dissolved oxygen infiltration, coexistence of metal ions and organic amines, there are deviations between theoretical and actual electron supply, which easily leads to unstable addition.

[0003] The prior art usually adopts stoichiometric feedforward addition based on the NO3- and NO2- load of influent, supplemented by ORP closed loop or effluent NOx feedback correction; there are also methods of taking the amount of sulfate generated or the potential threshold as a limiting condition, or adjusting the addition proportion as a whole by empirical rules after the absorption liquid is replaced. These schemes usually treat different sulfur sources such as sulfide, thiosulfate, sulfite and elemental sulfur by concentration or mass measurement, but less comprehensive evaluation on a unified electronic benchmark; the influence of amines as parallel electron donors and iron ions as competition / consumption factors is often not quantified; the decay of effectiveness caused by dissolved oxygen infiltration and absorption liquid use interval usually relies on after-adjustment; there is a lack of structured methods that allow the sulfur / nitrate electron ratio interval as a control target to be calculated first and adjusted later with restrictions.

[0004] The deficiencies of the above methods are: unable to accurately reflect the "effective sulfur electron number" before addition, causing deviation between feedforward and field, easily leading to nitrate leakage or excessive growth of sulfate, and causing corrosion risk; the feedback side increases the adjustment range for correction, leading to fluctuations and oscillations; when the iron content increases, DO infiltrates or the replacement interval is lengthened, the rules lack traceable quantitative correction and upper limit constraints, making it difficult to maintain a stable and operable sulfur / nitrate electron ratio window for a long time.

[0005] Therefore, how to provide a sulfur autotrophic denitrification sulfur source stable supply method that can solve the above technical problems is a problem that needs to be solved by those skilled in the art. SUMMARY

[0006] One object of the present application is to provide a sulfur autotrophic denitrification sulfur source stable supply method based on a sulfur source effectiveness evaluation model, aiming to unify the electrons required for denitrification and the effective electrons of the sulfur source to the same electronic benchmark under the condition of multi-factor fluctuations in the engineering field, and to complete the updateable correction and limited control before addition, so that the sulfur / nitrate electron ratio is always within the allowed operating range, thereby realizing the stable supply of sulfur source and taking into account the prevention of nitrate leakage and the inhibition of excessive sulfate.

[0007] The method for stably supplying a sulfur source for sulfur autotrophic denitrification based on a sulfur source effectiveness evaluation model according to the embodiment of the present application comprises:

[0008] S1, establishing an electronic consumption benchmark, obtaining the influent nitrate amount and the influent nitrite amount and calculating the required electron number, obtaining the sulfide, sulfur-containing salt, amine substance and iron content in the liquid for absorption and calculating the theoretical sulfur electron number;

[0009] S2, establishing a sulfur electron correction model, inputting the liquid index for absorption, the oxidation-reduction value, the dissolved oxygen in water and the replacement interval time, and outputting an adjustment coefficient to represent the deviation of the theoretical sulfur electron number;

[0010] S3, constructing a control scheme of calculation first and adjustment later with limitation, taking the electronic consumption benchmark as the core and setting the allowed operation range of the sulfur-to-nitrogen electron ratio;

[0011] S4, multiplying the theoretical sulfur electron number by the adjustment coefficient to obtain the corrected sulfur electron number, replacing the set value of the control scheme, calculating the sulfur addition flow rate according to the required electron number, and setting the upper limit of sulfur addition according to the sulfate increase and the oxidation-reduction value to avoid nitrate leakage and inhibit excessive sulfate;

[0012] S5, according to the relationship between the residual nitrate in the effluent, the residual nitrite in the effluent and the corrected sulfur electron number, performing a small-scale adjustment to stabilize the sulfur addition flow rate;

[0013] S6, updating the adjustment coefficient according to the change of the replacement interval time, the increase of the iron content and the infiltration of the dissolved oxygen in water to maintain the response to the site fluctuation by calculation first;

[0014] S7, outputting the stable supply result to maintain the sulfur-to-nitrogen electron ratio in the allowed operation range, realizing complete removal of nitrogen and controlling the sulfate increase and the corrosion risk.

[0015] Optionally, S1 specifically comprises:

[0016] The influent nitrate amount and the influent nitrite amount are obtained and recorded, and the required electron number is obtained by conversion according to the contribution of the two to the required electron number;

[0017] The sulfide, sulfur-containing salt, amine substance and iron content in the liquid for absorption are obtained and recorded, and the theoretical sulfur electron number is obtained by conversion according to the contribution of the four to the theoretical sulfur electron number;

[0018] The required electron number and the theoretical sulfur electron number are compared and summarized to form an electronic consumption benchmark, and the electronic consumption benchmark is the corresponding relationship between the required electron number and the theoretical sulfur electron number.

[0019] Optionally, S2 specifically comprises:

[0020] The sulfur electron correction model is a model with the absorption liquid index, the redox value, the dissolved oxygen in water, and the replacement interval time as inputs and the adjustment coefficient as a single output. The fixed direction relationship is used to limit that the increase of iron content leads to the decrease of the adjustment coefficient and the increase of the amine substance leads to the increase of the adjustment coefficient. The adjustment coefficient is compared with the electron consumption benchmark to represent the deviation of the theoretical sulfur electron number and correct the theoretical sulfur electron number;

[0021] The absorption liquid index, the redox value, the dissolved oxygen in water, and the replacement interval time are input into the sulfur electron correction model. The absorption liquid index is sulfide, sulfur-containing salt, amine substance, and iron content;

[0022] The theoretical sulfur electron number is associated with the sulfur electron correction model. The fixed direction relationship is used to set the change of the adjustment coefficient. According to the increase of iron content, the increase of the dissolved oxygen in water, and the extension of the replacement interval time, the adjustment coefficient is set to decrease. According to the increase of the amine substance and the increase of the sulfur-containing salt, the adjustment coefficient is set to increase;

[0023] The adjustment coefficient is compared with the electron consumption benchmark to output the adjustment coefficient, which is used to represent the deviation of the theoretical sulfur electron number and correct the theoretical sulfur electron number in the subsequent;

[0024] The adjustment coefficient is limited to a single output, which forms a one-to-one correspondence with the theoretical sulfur electron number, is used to replace the set value in the control scheme of calculating first and adjusting later with limitation, and is used to directly change the feedforward proportion of sulfur addition;

[0025] The range of the adjustment coefficient is limited according to the electron consumption benchmark. The upper limit and the lower limit are set to avoid excessive correction leading to the leakage of nitrate or the excess of sulfate.

[0026] Optionally, the adjustment coefficient is specifically:

[0027]

[0028] In the formula, is a value limiting function. When the internal quantity is less than , the output is , when the internal quantity is greater than , the output is , otherwise, the output is the internal quantity; is a bias term; , , , , , , is a non-negative parameter; The fixed direction that the increase of iron content leads to the decrease of the adjustment coefficient is implemented. and Implement the fixed direction that causes the adjustment coefficient to decrease due to the increase in dissolved oxygen in the water and the extension of the replacement interval; and as well as The fixed direction of the increase in adjustment coefficients due to the increase in amines, sulfur-containing salts, and sulfides should be established. Introduce redox values ​​into the mapping without changing the aforementioned fixed direction; and Based on electronic usage standards. The upper limit of the range of values ​​is denoted as The lower limit is denoted as .

[0029] Optionally, S3 specifically refers to:

[0030] By comparing the electron usage benchmark with the influent nitrate and nitrite levels, an initial allowable operating range for the sulfur to nitrate electron ratio is set. This allowable operating range consists of an upper limit and a lower limit, which are used to guide the initial calculation in a control scheme with pre-calculation and subsequent adjustment and limitations.

[0031] By referencing the redox value and adjustment coefficient, the initial allowable operating range is narrowed or widened. The lower limit is used to prevent nitrate leakage, and the upper limit is used to prevent excessive sulfur addition, thus forming the set value for sulfur addition.

[0032] Optionally, S4 specifically refers to:

[0033] The theoretical number of sulfur electrons is multiplied by the adjustment coefficient to obtain the corrected number of sulfur electrons. The corrected number of sulfur electrons is used to replace the pre-calculated setpoint in the control scheme with pre-calculation and post-adjustment and limitations, and is used to establish a setting consistent with the field before sulfur addition.

[0034] The sulfur addition flow rate is obtained by calculating the baseline of electron usage and the corrected number of sulfur electrons. The sulfur addition flow rate is used to guide sulfur addition, so that the sulfur addition corresponds to the required number of electrons.

[0035] The upper limit of sulfur addition is set by referencing the redox value and sulfate increase; the upper limit of sulfur addition is reduced when the redox value increases and relaxed when the redox value decreases; the upper limit of sulfur addition is reduced when the sulfate increase accelerates and relaxed when the sulfate increase slows down, in order to form a limit consistent with the field conditions.

[0036] The sulfur addition flow rate is compared with the upper limit of sulfur addition, and the output is adopted that does not exceed the upper limit of sulfur addition; this output is used to prevent nitrate leakage and suppress sulfate excess, while maintaining the electron ratio of sulfur to nitrate within the allowable operating range;

[0037] The changes in the number of sulfur electrons after correction and the changes in redox values ​​are used to adjust the upper limit of sulfur addition; the changes in sulfate growth are used to further adjust the upper limit of sulfur addition, so as to keep the limit synchronized with the field conditions during the sulfur addition process.

[0038] The results of sulfur addition flow rate and sulfur addition limit are output and interfaced with the control scheme of calculation and adjustment with limit; the output is used to reduce the adjustment range in subsequent stages, so that sulfur addition remains stable and consistent with the electronic usage benchmark.

[0039] Optionally, the sulfur addition flow rate is specifically:

[0040]

[0041] In the formula, The output sulfurization flow rate; For a value-restricted function, when the internal quantity is lower than... Time output When the internal quantity is higher than Time output Otherwise, output the internal value; The initial set value for the electron ratio of sulfur to nitrate; The required number of electrons; This refers to the influent flow rate; This is the corrected number of sulfur electrons; This is the lower limit of sulfur addition flow rate; This is the upper limit for sulfur addition.

[0042] Optional, S5 specifically includes:

[0043] The residual nitrate and residual nitrite in the effluent were collected and recorded. The results were compared with the corrected sulfur electron count and electron usage benchmark to determine the direction and magnitude of the minor adjustment.

[0044] The term "small adjustment" is defined as a low-amplitude adjustment of the sulfur addition flow rate without changing the upper limit of sulfur addition, in order to suppress fluctuations and avoid excessive changes.

[0045] Implement a low-amplitude adjustment, compare the adjusted sulfur addition flow rate with the allowable operating range, and keep the residual nitrate and nitrite in the effluent within the required range.

[0046] Optional, S6 specifically includes:

[0047] The changes in replacement interval, increase in iron content, and infiltration of dissolved oxygen in the water were acquired and recorded, and the adjustment coefficients were updated based on the sulfur electron correction model.

[0048] The updated adjustment coefficients are compared with the electronic dosage benchmark, and the pre-calculated setpoint in the control scheme with pre-calculation and post-adjustment and limitations is replaced to correct the feedforward ratio of sulfur addition.

[0049] The on-site fluctuations are explained as deviations from the allowable operating range caused by changes in replacement intervals, increased iron content, and the infiltration of dissolved oxygen in the water. This explanation is used to limit the update range so that the upper limit of sulfur addition remains unchanged.

[0050] The beneficial effects of this invention are:

[0051] This proposal suggests an improved method and technology for stable sulfur source supply based on electron equivalent. By establishing an electron consumption benchmark, the electron requirements of nitrates and nitrites in the influent are converted and compared with the theoretical sulfur electron requirements of sulfides, sulfur-containing salts, amines, and iron in the absorbent under the same electron benchmark. Based on this, the core setting of the sulfur feedforward is formed. Compared with the existing practice of determining the addition based solely on mass concentration or empirical ratio, this improvement achieves the matching of electrons on the demand side and the supply side before addition, clarifying the consumption of effective electrons by iron and the additional electron-donating effect of amines. This reduces the deviation between the feedforward setting and the actual situation from the source, making sulfur addition revolve around the electron requirement side, which helps to reduce nitrate leakage and inhibit the formation of excessive sulfate.

[0052] This proposal presents a novel sulfur electron correction model and its single adjustment coefficient control technique. Using absorbent parameters, redox value, dissolved oxygen, and replacement interval as inputs, it employs fixed-directional constraints to ensure that the adjustment coefficient decreases due to increased iron content, dissolved oxygen infiltration, and extended replacement intervals, while increasing amine and sulfur-containing salt concentrations lead to an increased adjustment coefficient. Under defined upper and lower limits, the model outputs the adjustment coefficient, providing a one-to-one correction to the theoretical sulfur electron count. This model directly corrects the feedforward ratio and replaces the setpoint with the adjustment coefficient, avoiding coupling and overcorrection caused by parallel parameter tuning of multiple variables. Furthermore, amplitude limiting and monotonicity ensure the traceability and reproducibility of the correction, allowing the setpoint to converge promptly with field fluctuations, achieving a balance between preventing nitrate leakage and suppressing excessive sulfate.

[0053] This proposal suggests a comprehensive method and technique involving calculation followed by adjustment with limitations. The method calculates the sulfur addition flow rate based on the corrected sulfur electron count, sets the allowable operating range for the sulfur to nitrate electron ratio, and determines the upper limit of addition by combining redox values ​​and sulfate growth. Subsequently, only a small percentage adjustment is made to the flow rate without changing the upper limit, and the adjustment coefficient is updated based on changes in replacement intervals, increases in iron content, and dissolved oxygen infiltration. This approach differs from control methods driven solely by ORP thresholds or effluent feedback. Through a chain structure of feedforward matching, amplitude constraints, small-scale adjustments, and coefficient updates, sulfur addition remains stable under load and operating condition disturbances, continuously maintaining the sulfur / nitrate electron ratio within the allowable operating range. This achieves the denitrification target while controlling sulfate increase and reducing corrosion risk, improving long-term operational consistency and controllability. Attached Figure Description

[0054] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0055] Fig. 1 This is a flowchart of the method for stable supply of sulfur source for sulfur autotrophic denitrification based on a sulfur source effectiveness assessment model proposed in this invention.

[0056] Fig. 2 This is a schematic diagram of the sulfur electron correction model for the sulfur autotrophic denitrification sulfur source stable supply method based on the sulfur source effectiveness assessment model proposed in this invention.

[0057] Fig. 3 This is a flowchart of the pre-calculation and post-adjustment scheme with limitations for the sulfur source stable supply method for sulfur autotrophic denitrification based on the sulfur source effectiveness assessment model proposed in this invention.

[0058] Fig. 4 This diagram illustrates a comparison of stable supply and risk control scenarios for the sulfur source stability supply method for sulfur autotrophic denitrification based on a sulfur source effectiveness assessment model proposed in this invention. Detailed Implementation

[0059] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0060] refer to Figs. 1 to 4 A method for stable sulfur source supply for sulfur autotrophic denitrification based on a sulfur source effectiveness assessment model includes:

[0061] S1. Establish a baseline for electron usage, obtain the amount of nitrate and nitrite in the influent and calculate the required number of electrons, obtain the content of sulfides, sulfur-containing salts, amines and iron in the absorption liquid and calculate the theoretical number of sulfur electrons.

[0062] S2. Establish a sulfur electron correction model, input the liquid index used for absorption, redox value, dissolved oxygen in water and replacement interval, and output the adjustment coefficient to characterize the deviation of the theoretical sulfur electron number.

[0063] S3. Construct a control scheme with pre-calculation and post-adjustment and limitations, with the electronic consumption benchmark as the core, and set the allowable operating range of the electronic ratio of sulfur to nitrate;

[0064] S4. Multiply the theoretical number of sulfur electrons by the adjustment coefficient to obtain the corrected number of sulfur electrons, replace the set value of the control scheme, calculate the sulfur addition flow rate according to the required number of electrons, and set the upper limit of sulfur addition according to the sulfate growth and redox value to avoid nitrate leakage and suppress sulfate excess.

[0065] S5. Based on the relationship between residual nitrate and residual nitrite in the effluent and the corrected number of sulfur electrons, a slight adjustment is made to stabilize the sulfur addition flow rate.

[0066] S6. Update and adjust the coefficients based on changes in replacement interval, increase in iron content, and infiltration of dissolved oxygen in the water, while maintaining the calculated response to on-site fluctuations.

[0067] S7 outputs a stable supply result, maintaining the electron ratio of sulfur to nitrate within the allowable operating range, achieving complete nitrogen removal and controlling sulfate increase and corrosion risk.

[0068] In this specific embodiment, S1 specifically refers to:

[0069] The samples were defined into two categories: the influent side and the liquid used for absorption. The influent side samples were set as the influent nitrate and nitrite levels, expressed as nitrogen, and denoted as [reference values ​​would be inserted here]. and The unit is mg / L. The liquid sampling variables for absorption are set as the concentration of sulfides and sulfur-containing salts (calculated as sulfur), the concentration of amines (calculated as mass), and the iron content (calculated as iron), respectively denoted as... , , , ,in and The unit is mg-S / L. The unit is mg / L. The unit is mg-Fe / L.

[0070] The sampling timestamps are recorded periodically, denoted as... The sampling period is denoted as All collected variables are timestamped. Perform corresponding storage and construct the intake side acquisition vector. Constructing the liquid acquisition vector for absorption The acquisition vector and timestamp are written into the recording unit at a fixed resolution.

[0071] After acquiring and recording the influent nitrate and nitrite levels, the required number of electrons is converted. The electron equivalent coefficient library is loaded into the conversion unit, and the nitrate contribution coefficient is set as follows: The contribution coefficient of nitrite is set as . .Will Fixed by dividing by 5 and then by 14, this represents the conversion factor for electron demand per unit concentration in nitrogen terms; Fixed by dividing by three and then by fourteen, this represents the electron requirement conversion factor per unit concentration of nitrogen. The recorded... and Perform multiplication and addition operations with the corresponding electron equivalent coefficients respectively, and output the required number of electrons, denoted as . The unit is mmol / L. [The remaining text appears to be incomplete and requires further context.] Store with timestamps to maintain consistency synchronous.

[0072] After acquiring and recording the sulfide, sulfur-containing salts, amines, and iron content in the absorption liquid, the theoretical sulfur electron count was calculated. The sulfide contribution coefficient from the electron equivalent coefficient library was denoted as... The contribution coefficient of sulfur-containing salts is denoted as The contribution coefficient of amines is denoted as The electron consumption coefficient of iron content is denoted as .Will Fixing by providing eight electrons per mole of sulfur, Using the electron equivalent per mole of sulfur as a constant, and employing a conversion constant in terms of sulfur, the following is... The electron equivalent per unit concentration was fixed, and the Sulfur is fixed by consuming one electron per mole of trivalent iron. The atomic weight of sulfur is denoted as... The value is 32; the atomic weight of nitrogen is denoted as... Its value is fourteen;

[0073] The atomic weight of iron is denoted as The value is 55.845. The recorded... , , , Convert the electrons to the corresponding units and atomic weights, then multiply, add, and subtract according to the corresponding electron equivalence coefficients to output the theoretical number of sulfur electrons, denoted as . The unit is mmol / L. [The remaining text appears to be incomplete and requires further context.] Store with timestamps to maintain consistency synchronous.

[0074] The required number of electrons is compared and summarized with the theoretical number of sulfur electrons to form a baseline for electron usage. This baseline is then applied to electrons from the same time stamp. and Perform corresponding associations and construct corresponding relationship vectors, denoted as . All timestamps Write it into the reference set according to the sampling period, denoted as .Will The storage structure serving as the electron consumption reference is the correspondence between the required number of electrons and the theoretical number of sulfur electrons.

[0075] Set a validity threshold for the recording unit, and record the lower limit for data collection as follows: The upper limit of collection is denoted as The levels of nitrate and nitrite in the influent should be kept below [a certain level]. The time marker is invalid and will not be included in the conversion; the content of sulfides, sulfur-containing salts, amines, and iron in the absorption liquid is below a certain level. or higher The timestamps are marked as invalid and will not be included in the conversion. Do not enter To maintain the validity of the benchmark set.

[0076] Sampling period Set to at least five minutes to ensure and Time correspondence. All conversions are performed on a timestamp concatenation basis, using a linear process of recording first and then converting, and converting first and then comparing, without inserting other processing steps.

[0077] The output structure of the electronic consumption benchmark is set to a two-column format, with the first column being... , the next column is The correspondence between each timestamp is written as an immutable entry, arranged in chronological order. The update strategy for the baseline set is set to append sequentially according to the sampling period, without backtracking or overwriting.

[0078] The actions of data collection, recording, conversion, comparison, and summarization in this specific embodiment shall be performed in the order described above. The objectives of all actions are respectively defined as obtaining the required number of electrons, obtaining the theoretical number of sulfur electrons, and establishing an electron utilization benchmark. The output of this specific embodiment shall be completed. It is used as a direct reference for electronic usage in subsequent stages.

[0079] In this specific embodiment, S2 specifically refers to:

[0080] The input objects are categorized into four types: liquid parameters for absorption, redox value, dissolved oxygen in water, and replacement interval. Liquid parameters for absorption are defined as sulfides, sulfur-containing salts, amines, and iron content, denoted as […]. , , , The units are mg-S / L, mg-S / L, mg / L, and mg-Fe / L, respectively. The redox value is denoted as... The unit is mV. The dissolved oxygen in water is denoted as... The unit is mg / L. The replacement interval is denoted as... The unit is hours (h). Enter the above input in the timestamp. The lower assembly is used as the input vector, maintaining consistency with the time series of the electron usage benchmark, to ensure consistency with the theoretical sulfur electron number. The one-to-one correspondence is not broken.

[0081] The adjustment factor is defined as a single output, denoted as . .Will As the sole control variable in the sulfur electron correction model, it is used to correlate the theoretical number of sulfur electrons at the same time stamp. Multiplying these yields the corrected number of sulfur electrons, which is then used to replace the set value in subsequent steps. This establishes the fixed-direction relationship at the parameter level, relating the iron content to... The effect is set to monotonically decrease, reducing the effect of amines on... The function is set to increase monotonically, while simultaneously increasing the amount of dissolved oxygen in the water. The function is set to monotonically decrease, adjusting the replacement interval time relative to... The function is set to monotonically decrease, thus affecting the interaction between sulfur-containing salts and sulfides. The function is set to increase monotonically. Redox values ​​are used as input for the mapping, without changing the aforementioned fixed-direction constraint.

[0082] The electronic consumption standard is denoted as It is composed of the correspondence between the required number of electrons and the theoretical number of sulfur electrons. Used to limit The range of values. Let the upper limit be denoted as... The lower limit is denoted as .Will and The search is based on The observation range is set so that for any timestamp ,Will and After multiplication, no excess is produced. Range offset. This range is used to prevent overcorrection that could lead to nitrate leakage or sulfate overdose.

[0083] The sulfur electron correction model is constructed as a constrained mapping. A linear interpretable structure is employed, with upper and lower bound pruning operators superimposed to generate candidate adjustment coefficients. Range constraints are then applied to ensure that a single output stably falls within the range defined by the electron quantity baseline. The directionality of each input quantity is fixed using parameter signs to prevent direction reversal during operation. The model is calculated once at each time stamp, and the output uniquely corresponds to that time stamp. .

[0084] The calculation rules for the sulfur electron correction model are set as follows:

[0085] ;

[0086] In the formula, For a function that restricts the value of an internal quantity, when the internal quantity is less than... Time output When the internal quantity is greater than Time output Otherwise, output the internal value; For bias terms; , , , , , , The parameter is non-negative. Implement the fixed direction that increases iron content leads to a decrease in the adjustment coefficient; and Implement the fixed direction that causes the adjustment coefficient to decrease due to the increase in dissolved oxygen in the water and the extension of the replacement interval; and as well as Implement the fixed direction that "the increase in amines, sulfur-containing salts, and sulfides leads to an increase in the adjustment coefficient." Introduce redox values ​​into the mapping without changing the aforementioned fixed direction; and Based on electronic usage standards.

[0087] Will Used for calculation and The value to be taken. The required number of electrons at each time stamp is evaluated against the theoretical number of sulfur electrons to obtain acceptable upper and lower boundary ranges. This range is then converted to... and The value is set to ensure that the model output does not exceed the bounds under any valid input. Bounds detection is used as a pre-pruning check; when the candidate adjustment coefficient is lower than... When the candidate adjustment coefficient is higher than a certain value, it is judged as a tendency to excessively reduce the value; when the candidate adjustment coefficient is higher than a certain value, it is judged as a tendency to excessively reduce the value. When this is detected, it is determined to have an excessive tendency to increase. After executing the clipping function, the final output is shown. .

[0088] Will With theoretical sulfur electron number Correlation is performed by multiplying the results at the same timestamp to obtain the corrected number of sulfur electrons. This corrected result is then compared with the electron dosage benchmark to determine the magnitude of the deviation at the same timestamp, and this deviation is retained for minor adjustments in subsequent stages. Invalid input timestamps are discarded, and inputs exceeding the range are marked and excluded from this process. Calculation and output.

[0089] Parameter calibration was performed using a combination of offline calibration and online fine-tuning. , , Set it to a constant that is not less than zero, keeping the direction unchanged. , , Set it to a constant that is not less than zero, keeping the direction unchanged. Set as an adjustable parameter to preferentially match the electron consumption baseline within different redox value ranges. and During initial operation, values ​​are assigned within a range defined by the electronic consumption benchmark. During operation, adjustments are only made after structural changes occur to the electronic consumption benchmark, without high-frequency modifications.

[0090] Set the output structure to a single-column time series, with the column name being the adjustment factor and the value being... Each timestamp outputs only a single scalar, maintaining a one-to-one correspondence with the theoretical sulfur electron count, without outputting other intermediate quantities. This single output is used to characterize the deviation from the theoretical sulfur electron count and to correct it, thus directly changing the feedforward ratio of sulfur addition. When this single output is invoked, its name, unit, and timestamp remain unchanged. After completing the above implementation, Provided for use in subsequent control schemes to ensure that the amount does not exceed the upper limit or fall below the lower limit, preventing excessive correction that could lead to nitrate leakage or sulfate overdose.

[0091] In this specific embodiment, S3 specifically refers to:

[0092] Set the input object as the electronic consumption baseline. nitrate levels in influent nitrite content in influent Oxidation-reduction value Adjustment coefficient Electronic usage benchmark The number of electrons required in With theoretical sulfur electron number Use a consistent reference with the timestamp without changing the chronological order. Define the electron ratio of sulfur to nitrate as a ratio variable, denoted as... The units are dimensionless. The allowed operating range is defined as the lower limit and upper limit, denoted as _____. and The setpoint for sulfur addition is defined as follows: The unit is dimensionless.

[0093] Electronic usage benchmark Compared with the current influent nitrate level With the amount of nitrite in the influent To verify the data, the required number of electrons matching the timestamp is retrieved. With theoretical sulfur electron number .Will and By comparing the results, a reference ratio is obtained, which is denoted as . The initial allowed operating range is set around a reference ratio, and the initial lower limit is denoted as... Let the initial upper limit be denoted as Let the initial tolerance be denoted as The unit is dimensionless. Stored as a fixed value and retrieved at each timestamp. and and Maintain the correspondence and do not change the sampling order. As the initial allowed operating range, it is used to guide the initial calculation in a control scheme with pre-calculation and subsequent adjustment and with constraints.

[0094] redox value With adjustment coefficient This is used to narrow or widen the initial allowed operating range. The target range for redox values ​​is set to... The unit is mV, where The lower threshold, The upper threshold is set. The discrimination threshold for the adjustment coefficient is set to... The unit is dimensionless, where For low threshold, The upper threshold is set as follows: The increment and decrement of the upper limit adjustment are denoted as... and The units are dimensionless. The increment and decrement of the lower limit adjustment are denoted as... and The units are dimensionless. The above thresholds and adjustment values ​​are stored fixedly in the parameter area, and their direction and units are not changed during operation.

[0095] Use redox values ​​to narrow or broaden the upper limit. and Comparison. When Higher than At that time, the initial upper limit will be... By performing a shrinkage process, a new upper limit is obtained. Using a fixed reduction .when Below At that time, the initial upper limit will be... By relaxing the restrictions, a new upper limit is obtained. Using a fixed increment .when When within the target range, direct as This upper limit is used to prevent excessive sulfur addition, without changing its role as a limit.

[0096] The adjustment factor is used to contract or widen the lower limit. and Comparison. When Below When, the initial lower limit is set. An improvement process is performed to obtain a new lower limit. Using a fixed increment This is used to prevent nitrate leakage. When Higher than When, the initial lower limit is set. A reduction process is performed to obtain a new lower limit. Using a fixed reduction .when When it is within the threshold range, direct as Using this lower limit to prevent nitrate leakage does not change its role as a lower limit.

[0097] The relative positions of the upper and lower limits are checked for consistency. and Compare the values. When the upper limit is not higher than the lower limit, either raise the upper limit by the smallest step or lower the lower limit by the smallest step, so that the upper limit is higher than the lower limit by a fixed difference, denoted as . The unit is dimensionless. This fixed difference is stored in the parameter area, and a one-time adjustment is performed when overlap occurs. The adjusted interval is taken as the final allowed operating range and kept as a closed interval.

[0098] The set value used for sulfurization Build within the final allowed range. and To reference them, use the middle position as... .Will The pre-calculated setpoint is marked as a control scheme with pre-calculation and post-adjustment constraints. Stored with timestamps and and Keep in sync.

[0099] The above process is executed once at each timestamp, with input to output following the sequence of comparison—setting—shrinking or relaxing—verification—output, without inserting any other processing. All thresholds and adjustment values ​​are managed uniformly in the parameter area, maintaining consistent direction and preserving the established functional allocation of "upper limit to prevent excessive sulfurization" and "lower limit to prevent nitrate leakage." The results are output in a three-column structure, respectively... , , Used in subsequent stages With the required number of electrons The parameters are referenced to form a pre-calculated setpoint for sulfur addition. Unavailable input times are marked and excluded from the current generation to prevent output out-of-bounds errors. After this implementation is completed, it directly provides ranges and setpoints for subsequent control stages, ensuring that the pre-calculated and then adjusted control scheme with limitations has clear upper and lower limits, and has a time correspondence consistent with the electronic dosage benchmark and the influent nitrate and nitrite levels.

[0100] In this specific embodiment, S4 specifically refers to:

[0101] Set the input object to the theoretical number of sulfur electrons. Adjustment coefficient Corrected sulfur electron number Electronic usage standards Number of electrons required Inlet flow rate Oxidation-reduction value sulfate concentration Sulfate growth determination value , sulfur addition flow , upper limit of sulfur addition , lower limit sulfur addition flow rate The initial set value for the electron ratio of sulfur to nitrate. Set the units as mmol / L, dimensionless, mmol / L, aggregate, constant, L / h, mV, mg / L, and mg / L· respectively. L / h, L / h, L / h, dimensionless.

[0102] Multiply the theoretical sulfur electron number by the adjustment factor to obtain the corrected sulfur electron number. (Using the same timestamp...) Below and Perform multiplication to obtain .Will This is used to replace the pre-calculated setpoint in a control scheme with pre-calculation and subsequent adjustment and limitations. The replacement is performed on a timestamp-cascaded basis, without changing the time sequence or units. Keep it within the allowed operating range, As a pre-calculated setpoint before sulfurization, and Synchronous call.

[0103] The sulfur addition flow rate is obtained by calculating the corrected sulfur electron count against the baseline for electron usage. In and With inflow rate The process involves referencing a fixed conversion relationship to generate candidate values ​​for sulfur addition flow rates. These candidate values ​​are then used to guide sulfur addition, establishing a correspondence between sulfur addition and the required number of electrons. The unit remains L / h, and the name is not changed.

[0104] The redox value and sulfate increase are used to set the upper limit for sulfur addition. The basic upper limit is denoted as... This stems from the boundaries of equipment capabilities and process safety.

[0105] Set the target range for redox values ​​to :

[0106] when Higher than At that time, Fixed reduction By reducing the value, we obtain the upper limit of the middle range;

[0107] when Below At that time, By fixed increment By relaxing the limits, we obtain the middle upper limit;

[0108] when If it is within the interval, it remains unchanged.

[0109] The threshold for determining sulfate growth is set as follows: :

[0110] when Higher than At that time, the upper limit of the middle section will be reduced by a fixed amount. Reduce to obtain ;

[0111] when Below At that time, the upper limit of the middle section will be increased by a fixed increment. Relaxing the restrictions resulted in ;

[0112] when If it is within the interval, it remains unchanged.

[0113] Will No less than the lower limit of sulfur addition flow rate , used to create constraints consistent with the on-site conditions.

[0114] The sulfurization flow rate is compared to the sulfurization limit, and the output flow rate not exceeding the limit is used. The comparison is performed on a timestamp-cascaded basis, and the output flow rate is recorded as... This output is used to prevent nitrate leakage and suppress sulfate excess, while also maintaining the sulfur to nitrate electron ratio within the allowable operating range. and Maintain consistency and avoid exceeding limits .

[0115] The changes in the number of sulfur electrons after correction are used in conjunction with the changes in redox values ​​to adjust the upper limit of sulfur addition. When the rate of change exceeds a fixed threshold, triggering... This is a one-time fine-tuning, consistent with the rules governing redox values ​​and sulfate growth. The changes in sulfate growth are referenced to further adjust the upper limit of sulfur addition, with only one overlay performed at the same timestamp, without changing the order. This adjustment is used to keep the limits synchronized with the field conditions during sulfur addition.

[0116] The results of sulfur injection flow rate and sulfur injection limit are output and interfaced with a control scheme that calculates and adjusts before adjustment and includes limits. The output structure is set as a single-column time series, with the column name being sulfur injection flow rate and the value being... The unit is L / h. This output is used to reduce adjustment range in subsequent stages, keeping sulfur addition stable and consistent with the electronic dosage benchmark. Inconsistent input times are marked and not included in output generation, maintaining time correspondence and unit stability.

[0117] The sole calculation formula used for sulfurization is set as follows and called once when generating the sulfurization flow rate:

[0118]

[0119] In the formula, The output sulfurization flow rate; For a value-restricted function, when the internal quantity is lower than... Time output When the internal quantity is higher than Time output Otherwise, output the internal value; The initial set value for the electron ratio of sulfur to nitrate; The required number of electrons; This refers to the influent flow rate; This is the corrected number of sulfur electrons; This is the lower limit of sulfur addition flow rate; This is the upper limit for sulfur addition.

[0120] The above implementation method is executed in sequence. First, the corrected sulfur electron count is generated, then the pre-calculated set value is replaced, then the sulfur addition flow rate is calculated based on the electron usage benchmark and the corrected sulfur electron count. Then, the sulfur addition upper limit is set and compared and the output is limited. Finally, the sulfur addition upper limit is adjusted according to the changes in the field conditions and the output is connected.

[0121] In this specific embodiment, S5 specifically includes:

[0122] The samples were set as nitrate residue and nitrite residue in the effluent, respectively denoted as... and The unit is mg / L. Combine this with the timestamp. Record the corresponding data and construct the water outlet side acquisition vector. .

[0123] The recording unit uses a fixed sampling period. Perform the write operation to maintain consistency with the electronic usage baseline. The time series are consistent and the units are not changed. The compliance threshold is set to [value]. and The unit is mg / L, used to determine whether the residual nitrate and residual nitrite in the effluent are within or exceed the required limits.

[0124] The corrected number of sulfur electrons is denoted as The required number of electrons in the electron usage standard is recorded as The candidate sulfurization flow rate is denoted as The upper limit of sulfur addition is denoted as The lower and upper limits of the allowed operating range are denoted as follows: and The electron ratio of sulfur to nitrate is denoted as .

[0125] After acquiring and recording the residual nitrate and nitrite in the effluent, the direction and magnitude of the minor adjustment were determined by comparing them with the corrected sulfur electron count and electron consumption baseline. The direction was defined as either incremental or decremental. Incremental adjustments were used to increase the sulfur injection flow rate when signs of insufficient electrons appeared on the effluent side, while decremental adjustments were used to decrease the sulfur injection flow rate when signs of excessive electron supply appeared on the effluent side. The criteria for determining the increment were set as follows: Higher than or Higher than or Below The criteria for determining the reduction are set as follows: Not higher than and Not higher than and Higher than The moment when the above two conditions are not met is recorded as a maintenance state, which is a state in which the sulfur injection flow rate does not change.

[0126] The slight adjustment is limited. The percentage adjustment range is denoted as... The unit is dimensionless. The upper limit is denoted as A single step is recorded as ,Will The lower limit is denoted as ,satisfy .Will and This parameter is stored in the parameter area to prevent abrupt changes during low-amplitude adjustments. The constraint for small-amplitude adjustments is set to not change the upper limit of sulfur addition. Without changing the constraint on the lower limit of sulfur injection flow rate, all ratio adjustments will only apply to candidates for sulfur injection flow rate. .

[0127] Execute the adjustment with a low amplitude ratio. (The increment time...) Used to improve The value will be the value at the moment of reduction. Used to reduce The value will remain unchanged at that time. The execution process will... The sulfur injection flow rate is compared and found to be neither exceeding the upper limit nor falling below the lower limit. The adjusted sulfur injection flow rate is recorded as... ,Will Store with timestamps to maintain consistency with the input.

[0128] The adjusted sulfur injection flow rate was compared with the allowable operating range. The electron ratio of sulfur to nitrate at the adjusted time was recorded as... , in the interval Internal verification is required.

[0129] when Below At that time, the next moment Lift by the minimum step size, keeping the direction incremental;

[0130] when Higher than At that time, the next moment Lower the vehicle in the smallest possible increments, maintaining a decreasing direction.

[0131] when When it is within the interval, the next time step will be... Keep it unchanged. Use this control to suppress fluctuations and avoid excessive changes, keeping the sulfurization flow rate within the permissible operating range.

[0132] The determination that the residual nitrate and residual nitrite in the effluent are within the required range is performed once at each time stamp. and In comparison, and Comparison. When neither value exceeds its respective threshold, the state is recorded as qualified; when either value exceeds its threshold, the state is recorded as exceeded. The qualified state is then compared to the state at the specified time. Freeze the data; do not increment or decrement it. This will affect the data at the time of exceeding the limit. Directional adjustments will be made, prioritizing incremental increases, but the upper limit for sulfur addition and the names and meanings of the upper and lower limits of the permitted operating range will remain unchanged.

[0133] Set the execution cycle for the minor adjustment to be... ,Will Not less than the sampling period Perform the scaling adjustment only once per cycle to avoid repeated triggering. Record all adjustments in the post-adjustment sequence, denoted as... Time series, and Synchronous storage is used for traceability and verification.

[0134] The handling of abnormal inputs is set to single-step rejection. Invalid moments for residual nitrates and nitrites in the effluent are marked and not included in the current ratio adjustment, nor are the sulfurization flow rate output changed. Normal execution resumes at the next time point after rejection, maintaining the continuity of the time series.

[0135] The sequence of actions in this specific implementation method is set as follows: acquisition and recording—comparison and judgment—limitation and execution—comparison and verification—output and storage. The objectives of each action are defined as: determining the direction and magnitude of small-amplitude adjustments, completing low-amplitude proportional adjustments, maintaining the sulfurization flow rate within the allowable operating range, and maintaining the residual flow on the effluent side within the required range. Upon completion of this specific implementation method, the sulfurization flow rate is output. Adjustment range of proportion This is for use in subsequent processes, maintaining the sulfur cap unchanged. The premise is stable operation and compatibility with electronic usage benchmarks. Consistent.

[0136] In this specific embodiment, S6 specifically refers to:

[0137] Set the input object to the replacement interval. Iron content Oxygen dissolved in water Combine the above input with the timestamp. Acquisition and recording are performed, and the sampling period is denoted as . Without changing the units or names, define the input change as... , , This is used to describe the intensity of change between adjacent time points. The change determination threshold is set to... , , This is used to distinguish between inputs in a stable state and those in a perturbed state. The single output of the sulfur electron correction model is defined as the adjustment coefficient. The adjustment coefficient of the previous moment is denoted as The range of values ​​for the adjustment coefficient is defined as follows: It is consistent with the electronic usage standard and does not change the directional constraints.

[0138] After acquiring and recording data on changes in replacement intervals, increases in iron content, and the infiltration of dissolved oxygen into the water, a sulfur electron correction model was invoked to... Using the liquid parameters for absorption as input, candidate adjustment coefficients are generated, denoted as... The candidate adjustment coefficients were checked according to a fixed directional relationship, maintaining the principle that "increased iron content leads to..." "Reduce" "The increase in dissolved oxygen in the water" "Reduce" "Extend the replacement interval" The monotony of "reducing" is maintained while "the increase in amines and sulfur-containing salts makes..." The monotonicity of "increasing". Perform range cropping, limiting to Within, the updated adjustment coefficient is obtained, denoted as... .

[0139] The updated adjustment factor will be compared with the electronic consumption benchmark. Compare the results. Number of electrons required for the same timestamp With theoretical sulfur electron number To quote, and Correlation yields the corrected number of sulfur electrons. .Will The control scheme with pre-calculation and post-adjustment and limitations is adopted, replacing the original pre-calculated setpoint without changing the signs of the upper and lower limits of the allowable operating range or the time correspondence. This replacement is then used to correct the feedforward ratio for sulfur addition, synchronizing the feedforward side with the field conditions.

[0140] The field fluctuations are described below. Field fluctuations are defined as deviations from the permissible operating range caused by changes in replacement intervals, increased iron content, and the infiltration of dissolved oxygen into the water. The descriptive quantity for field fluctuations is defined as a vector. Reference the allowed scope as The current electron ratio of sulfur to nitrate is denoted as The deviation scalar is denoted as , used to characterize relatively The degree of deviation. The on-site fluctuation score is recorded as... , used to The intensity of change is mapped to a single threshold comparable quantity.

[0141] The on-site fluctuation description is used to limit the update range, while keeping the sulfur addition limit unchanged. The sulfur addition limit is denoted as... No changes are made in this step. The maximum single update magnitude of the adjustment coefficient is defined as... The minimum step size is defined as Define the dead zone threshold as .when When the value is above the upper threshold, only pressing the button is allowed. right Perform a single fine-tuning and freeze. .when Located between the upper and lower thresholds and When the deviation threshold is not exceeded, it is allowed to be based on a value not exceeding the threshold. The magnitude is updated once and then frozen. .when Below the lower threshold and Less than At that time, maintain Unchanged and frozen The above restrictions will ensure that the update action does not trigger a change in the upper limit.

[0142] The pre-calculated setpoints in the control scheme with pre-calculation and post-adjustment and limitations are replaced according to timestamps. The object to be replaced is set to the pre-calculated setpoint used for sulfur feedforward calculation, and the replacement amount is set to... Perform a consistency check immediately after the replacement, and then refer to... and Conduct a control group, when the control group results show If there is a possibility of crossing the boundary, press right Perform reverse fine-tuning to maintain lie in Internally, after verification, output the updated version. and and maintain constant.

[0143] Define the update cycle as Not less than the sampling period The sequence of acquisition and recording—model generation—range pruning—benchmark comparison—amplitude limitation—set replacement—consistency check—output storage will be executed only once within each update cycle, without inserting other actions. Invalid input moments will be marked, and no updates will be performed or changes made. and .

[0144] After completing this specific implementation method, three results will be output: the updated adjustment coefficients. Corrected sulfur electron number The upper limit of sulfur addition after freezing The above results are then provided to subsequent sulfur injection flow calculations and minor adjustments to achieve coordinated operation of feedforward proportional correction and unchanged upper limit.

[0145] In this specific embodiment, S7 specifically refers to:

[0146] Define the output structure as a stable supply result, in timestamps. The following is generated. The control parameters will be included. , , Include state variables , , Water quality measurement includes , , , , .

[0147] Will and Compare the results and output the judgment results for in-range and out-of-range conditions, along with... Include this in the stable supply results. and In comparison, and Compare the results and output whether the requirements are met, then archive these results together with the previously mentioned results. and In comparison, and The results of the comparison and output of the determination of sulfate increment control and corrosion risk control are presented.

[0148] Set the field order of the stable supply results to: , , , , , , , , , , And the corresponding judgment results. The moments of exceeding limits and exceeding boundaries are marked and linked to the record of the previous moment for use in subsequent steps. The combined result of compliance with allowable range, qualified nitrogen removal, controlled sulfate increase, and controllable corrosion risk is marked as stable and included in the record. Output is used to maintain the electron ratio of sulfur to nitrate within the allowable operating range.

[0149] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for stable sulfur source supply for sulfur autotrophic denitrification based on a sulfur source effectiveness assessment model, characterized in that, Includes the following steps: S1. Establish a baseline for electron usage, obtain the amount of nitrate and nitrite in the influent and calculate the required number of electrons, obtain the content of sulfides, sulfur-containing salts, amines and iron in the absorption liquid and calculate the theoretical number of sulfur electrons. S2. Establish a sulfur electron correction model, input the liquid index used for absorption, redox value, dissolved oxygen in water and replacement interval, and output the adjustment coefficient to characterize the deviation of the theoretical sulfur electron number. S3. Construct a control scheme with pre-calculation and post-adjustment and limitations, with the electronic consumption benchmark as the core, and set the allowable operating range of the electronic ratio of sulfur to nitrate; S4. Multiply the theoretical number of sulfur electrons by the adjustment coefficient to obtain the corrected number of sulfur electrons, replace the set value of the control scheme, calculate the sulfur addition flow rate according to the required number of electrons, and set the upper limit of sulfur addition according to the sulfate growth and redox value to avoid nitrate leakage and suppress sulfate excess. S5. Based on the relationship between residual nitrate and residual nitrite in the effluent and the corrected number of sulfur electrons, a slight adjustment is made to stabilize the sulfur addition flow rate. S6. Update and adjust the coefficients based on changes in replacement interval, increase in iron content, and infiltration of dissolved oxygen in the water, while maintaining the calculated response to on-site fluctuations. S7 outputs a stable supply result, maintaining the electron ratio of sulfur to nitrate within the allowable operating range, achieving complete nitrogen removal and controlling sulfate increase and corrosion risk.

2. The method for stable supply of sulfur source for sulfur autotrophic denitrification based on a sulfur source effectiveness assessment model according to claim 1, characterized in that, S1 specifically refers to: The amounts of nitrate and nitrite in the influent were acquired and recorded. The required number of electrons was calculated based on the contribution of each to the number of electrons required. The contents of sulfides, sulfur-containing salts, amines, and iron in the absorption liquid are obtained and recorded. The theoretical number of sulfur electrons is obtained by converting the contributions of the four to the theoretical number of sulfur electrons. The required number of electrons is compared and summarized with the theoretical number of sulfur electrons to form an electron usage benchmark, which is the correspondence between the required number of electrons and the theoretical number of sulfur electrons.

3. The method for stable supply of sulfur source for sulfur autotrophic denitrification based on a sulfur source effectiveness assessment model according to claim 1, characterized in that, S2 specifically refers to: The sulfur electron correction model is a model that takes the liquid index, redox value, dissolved oxygen in water and replacement interval as inputs and adjustment coefficient as the single output. It adopts a fixed directional relationship to limit the adjustment coefficient to decrease when iron content increases and to increase when amine content increases. It is compared with the electron usage benchmark to characterize the deviation of the theoretical sulfur electron number and to correct the theoretical sulfur electron number. The indicators of the absorbent liquid, the redox value, the dissolved oxygen in the water, and the replacement interval are input into the sulfur electron correction model. The indicators of the absorbent liquid are sulfides, sulfur-containing salts, amines, and iron content. The theoretical number of sulfur electrons is correlated with the sulfur electron correction model, and the adjustment coefficient is set to change using a fixed-direction relationship. The adjustment coefficient is set to decrease based on the increase in iron content, the increase in dissolved oxygen in water, and the extension of the replacement interval. The adjustment coefficient is set to increase based on the increase in amines and sulfur-containing salts. The electron usage benchmark is compared with the adjustment coefficient, and the adjustment coefficient is output to characterize the deviation of the theoretical sulfur electron number and to correct the theoretical sulfur electron number in the future. The adjustment coefficient is limited to a single output, forming a one-to-one correspondence with the theoretical number of sulfur electrons. It is used to replace the set value in a control scheme with pre-calculation and post-adjustment and limitations, and to directly change the feedforward ratio of sulfur addition. The range of the adjustment coefficient is limited according to the electronic usage standard, and the setting is no greater than the upper limit and no less than the lower limit to avoid excessive correction that could lead to nitrate leakage or excessive sulfate.

4. The method for stable supply of sulfur source for sulfur autotrophic denitrification based on a sulfur source effectiveness assessment model according to claim 3, characterized in that, The adjustment coefficient is specifically: ； In the formula, For a function that restricts the value of an internal quantity, when the internal quantity is less than... Time output When the internal quantity is greater than Time output Otherwise, output the internal value; For bias terms; , , , , , , The parameter is non-negative. Implement the fixed direction that increases iron content leads to a decrease in the adjustment coefficient; and Implement the fixed direction that causes the adjustment coefficient to decrease due to the increase in dissolved oxygen in the water and the extension of the replacement interval; and as well as The fixed direction of the increase in adjustment coefficients due to the increase in amines, sulfur-containing salts, and sulfides should be established. Introduce redox values ​​into the mapping without changing the aforementioned fixed direction; and Based on electronic usage standards. The upper limit of the range of values ​​is denoted as The lower limit is denoted as .

5. The method for stable supply of sulfur source for sulfur autotrophic denitrification based on a sulfur source effectiveness assessment model according to claim 1, characterized in that, S3 specifically refers to: By comparing the electron usage benchmark with the influent nitrate and nitrite levels, an initial allowable operating range for the sulfur to nitrate electron ratio is set. This allowable operating range consists of an upper limit and a lower limit, which are used to guide the initial calculation in a control scheme with pre-calculation and subsequent adjustment and limitations. By referencing the redox value and adjustment coefficient, the initial allowable operating range is narrowed or widened. The lower limit is used to prevent nitrate leakage, and the upper limit is used to prevent excessive sulfur addition, thus forming the set value for sulfur addition.

6. The method for stable supply of sulfur source for sulfur autotrophic denitrification based on a sulfur source effectiveness assessment model according to claim 1, characterized in that, S4 specifically refers to: The theoretical number of sulfur electrons is multiplied by the adjustment coefficient to obtain the corrected number of sulfur electrons. The corrected number of sulfur electrons is used to replace the pre-calculated setpoint in the control scheme with pre-calculation and post-adjustment and limitations, and is used to establish a setting consistent with the field before sulfur addition. The sulfur addition flow rate is obtained by calculating the baseline of electron usage and the corrected number of sulfur electrons. The sulfur addition flow rate is used to guide sulfur addition, so that the sulfur addition corresponds to the required number of electrons. By referencing the redox value and sulfate increase, an upper limit for sulfur addition is set; The upper limit of sulfur addition is reduced based on an increase in redox value and relaxed based on a decrease in redox value; the upper limit of sulfur addition is reduced based on an acceleration in sulfate growth and relaxed based on a slowdown in sulfate growth, in order to form a limit consistent with the field conditions. The sulfur addition flow rate is compared with the upper limit of sulfur addition, and the output is adopted that does not exceed the upper limit of sulfur addition; this output is used to prevent nitrate leakage and suppress sulfate excess, while maintaining the electron ratio of sulfur to nitrate within the allowable operating range; The changes in the number of sulfur electrons after correction and the changes in redox values ​​are used to adjust the upper limit of sulfur addition; the changes in sulfate growth are used to further adjust the upper limit of sulfur addition, so as to keep the limit synchronized with the field conditions during the sulfur addition process. The results of sulfur addition flow rate and sulfur addition limit are output and interfaced with the control scheme of calculation and adjustment with limit; the output is used to reduce the adjustment range in subsequent stages, so that sulfur addition remains stable and consistent with the electronic usage benchmark.

7. The method for stable supply of sulfur source for sulfur autotrophic denitrification based on a sulfur source effectiveness assessment model according to claim 5, characterized in that, The specific sulfurization flow rate is: ； In the formula, The output sulfurization flow rate; For a value-restricted function, when the internal quantity is lower than... Time output When the internal quantity is higher than Time output Otherwise, output the internal value; The initial set value for the electron ratio of sulfur to nitrate; The required number of electrons; This refers to the influent flow rate; This is the corrected number of sulfur electrons; This is the lower limit of sulfur addition flow rate; This is the upper limit for sulfur addition.

8. The method for stable supply of sulfur source for sulfur autotrophic denitrification based on a sulfur source effectiveness assessment model according to claim 1, characterized in that, S5 specifically refers to: The residual nitrate and residual nitrite in the effluent were collected and recorded. The results were compared with the corrected sulfur electron count and electron usage benchmark to determine the direction and magnitude of the minor adjustment. The term "small adjustment" is defined as a low-amplitude adjustment of the sulfur addition flow rate without changing the upper limit of sulfur addition, in order to suppress fluctuations and avoid excessive changes. Implement a low-amplitude adjustment, compare the adjusted sulfur addition flow rate with the allowable operating range, and keep the residual nitrate and nitrite in the effluent within the required range.

9. The method for stable supply of sulfur source for sulfur autotrophic denitrification based on a sulfur source effectiveness assessment model according to claim 1, characterized in that, S6 specifically refers to: The changes in replacement interval, increase in iron content, and infiltration of dissolved oxygen in the water were acquired and recorded, and the adjustment coefficients were updated based on the sulfur electron correction model. The updated adjustment coefficients are compared with the electronic dosage benchmark, and the pre-calculated setpoint in the control scheme with pre-calculation and post-adjustment and limitations is replaced to correct the feedforward ratio of sulfur addition. The on-site fluctuations are explained as deviations from the allowable operating range caused by changes in replacement intervals, increased iron content, and the infiltration of dissolved oxygen in the water. This explanation is used to limit the update range so that the upper limit of sulfur addition remains unchanged.

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