A method for evaluating and screening the overall performance of microalgae-microorganism fuel cell systems.

Abstract

This invention discloses a method for evaluating and screening the comprehensive performance of microalgae-microorganism fuel cell systems. Addressing the difficulty in systematizing and modeling the comprehensive performance evaluation of microalgae-microorganism fuel cell hybrid systems, this invention introduces the efficiency coefficient method into the evaluation method for the comprehensive performance of hybrid systems. A comprehensive performance evaluation model for the system is constructed, with maximizing the energy utilization rate of the hybrid system as the design principle. Four parameters—carbon sequestration efficiency, energy recovery rate, number of processes, and system volume—are determined as evaluation indicators. Through theoretical analysis combined with experimental research, the evaluation method and steps of the evaluation system are described. The comprehensive performance of different microalgae-microorganism fuel cell hybrid systems is evaluated, thereby enabling the selection of superior and inferior hybrid systems and providing theoretical guidance for system operation strategy optimization and practical engineering applications.

Description

Technical Field

[0001] This invention belongs to the field of biomass energy utilization technology, and specifically relates to a method for evaluating and screening the comprehensive performance of a microalgae-microorganism fuel cell system. Background Technology

[0002] In recent years, microalgae-microorganism fuel cell hybrid bioenergy systems have shown promise for practical applications in confined space CO2 fixation and microenvironment air treatment due to their advantages of small size, low energy consumption, high efficiency, and environmental friendliness. Before application, a comprehensive consideration of various factors is necessary, such as system cost, key performance indicators, process complexity, and system efficiency. However, these indicators are often contradictory, which undoubtedly poses challenges to the comprehensive performance evaluation and selection of hybrid systems.

[0003] Currently, the evaluation of microalgae-microorganism fuel cell hybrid systems mainly uses input energy, output energy, total energy conversion efficiency, and recovered energy as key evaluation indicators. Existing literature has used the recovered energy per unit volume of wastewater treated as an indicator to evaluate the overall performance of microalgae-microorganism fuel cell systems. Other studies have used total output energy as an indicator to evaluate the overall performance of microalgae-microorganism fuel cell systems. Still other literature uses the system energy recovery rate as an indicator to assess and analyze the system's energy conversion balance.

[0004] Overall, evaluating the comprehensive performance of a system using energy balance analysis still has some limitations. For example, certain factors (such as light energy consumption and pump power consumption) are not fully considered during the calculation of input / output energy, leading to inaccurate energy balance analysis. Secondly, factors such as system cost, process complexity, key performance indicators, efficiency, and environmental friendliness are not fully considered. Therefore, the key to the successful application of this type of hybrid bioenergy system lies in how to use scientific methods to coordinate and summarize various conflicting indicators, thereby objectively and comprehensively evaluating the system's overall performance and selecting the optimal system. Summary of the Invention

[0005] To overcome the shortcomings of the prior art, the present invention aims to provide a method for evaluating and screening the comprehensive performance of microalgae-microorganism fuel cell systems. The purpose is to establish an evaluation system for the comprehensive performance of hybrid systems by assembling a reasonable microalgae-microorganism fuel cell performance evaluation device, thereby solving the problem that it is difficult to "systematize, model, and quantify" the comprehensive performance evaluation of systems, and thus realizing the screening of the merits of hybrid systems and providing guidance for optimizing operation strategies.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A method for evaluating and screening the overall performance of a microalgae-microorganism fuel cell system includes the following steps:

[0008] Step 1: Obtain the evaluation indicators and the satisfaction value X of the i-th evaluation indicator. hi Value X is not allowed. si Single-item efficacy coefficient d i and weighting coefficient f i The evaluation indicators include microalgae carbon fixation efficiency, energy recovery rate, process complexity, and system volume; the satisfaction value X hi The highest level that the i-th evaluation indicator may reach during the evaluation calculation process is defined as the unacceptable value X. si The i-th evaluation indicator should not reach the minimum level required during the evaluation calculation process; the single-item efficacy coefficient d i According to the satisfaction value X hi and the disallowed value X si The weighting coefficient f is calculated and obtained. i It is used to quantitatively reflect the importance of the corresponding evaluation indicators, and is calculated using the coefficient of variation method;

[0009] Step 2, based on the weighting coefficient f of each evaluation indicator i and single-item efficacy coefficient d i The overall efficiency coefficient (EC) of the target system for the microalgae-microorganism fuel cell is calculated. The target system with the highest EC has the best overall performance and the highest energy utilization rate. For systems with EC below the set value, the indicator with both high individual efficiency coefficient and high weight coefficient is selected from all evaluation indicators. This indicator is the most critical indicator determining the system's performance. Then, the indicator is analyzed to determine the process parameters affecting it. Subsequently, experimental control groups under different operating conditions are set up and included in the sample. The sample is then evaluated again using the evaluation system to determine the optimal operating conditions, thereby achieving optimized control of the system's operating strategy.

[0010] Compared with the prior art, the beneficial effects of the present invention are:

[0011] For microalgae-microbe fuel cell hybrid bioenergy systems, this invention comprehensively considers key evaluation indicators such as carbon sequestration performance, energy recovery rate, number of processes, and system volume. It rationally constructs a comprehensive performance evaluation system based on the efficiency coefficient method, achieving an "objective, comprehensive, and quantitative" assessment of the overall performance of such systems, thereby maximizing system energy utilization. Furthermore, based on the calculation results fed back from this evaluation system, systems with poor overall performance are evaluated and screened, and the operating conditions corresponding to indicators with low efficiency coefficients are optimized, resulting in lower final system input costs, higher efficiency, and better meeting the needs of next-generation energy conversion devices. Based on the comprehensive performance evaluation and screening method proposed in this invention, it provides theoretical guidance for the application of microalgae-microbe fuel cell hybrid systems in confined space CO2 fixation, microenvironment air treatment, and other fields, demonstrating great promise. Attached Figure Description

[0012] Figure 1 This is a flowchart illustrating the system comprehensive performance evaluation system based on the efficacy coefficient method in this invention.

[0013] Figure 2 This invention provides a comprehensive performance evaluation and screening device for six different types of microalgae-microorganism fuel cells.

[0014] Figure 3 This is a comparison of the total efficacy coefficient results of different systems of the present invention. Detailed Implementation

[0015] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings and examples.

[0016] To address the challenge of systematically and modeling the comprehensive performance evaluation of microalgae-microorganism fuel cell hybrid systems, this invention presents a method for evaluating and screening the comprehensive performance of such systems. The efficiency coefficient method is introduced into the evaluation of hybrid system performance, constructing a comprehensive performance evaluation model. Maximizing the energy utilization rate of the hybrid system is the design principle, and four parameters—carbon sequestration efficiency, energy recovery rate, number of processes, and system volume—are determined as evaluation indicators. Through a combination of theoretical analysis and experimental research, the evaluation methods and steps are described, and the comprehensive performance of different microalgae-microorganism fuel cell hybrid systems is evaluated. This enables the selection of superior and inferior hybrid systems and provides theoretical guidance for system operation strategy optimization and practical engineering applications.

[0017] like Figure 1 As shown, the present invention mainly includes the following steps:

[0018] Step 1: Obtain evaluation indicators. These indicators must adhere to the principles of "independence, representativeness, and complementarity." In this invention, they are selected based on microalgae carbon fixation efficiency, energy recovery rate, process complexity, and system volume. The satisfactory value X of the i-th evaluation indicator is then obtained. hi Value X is not allowed. si Single-item efficacy coefficient d i and weighting coefficient f i .

[0019] Each evaluation index is obtained through experimental testing or calculation of the target system. Specifically:

[0020] The carbon fixation efficiency of microalgae is calculated by determining the difference in CO2 concentration between the inlet and outlet of the microalgae photobioreactor, and the formula is as follows:

[0021]

[0022] In the formula, CRE represents the microalgal carbon fixation efficiency (%); C min Indicates the imported CO2 concentration (%); C mout This indicates the CO2 concentration at the export site in percent.

[0023] The energy recovery rate is calculated by testing the input and output energy of the system, and the formula is as follows:

[0024]

[0025] In the formula, η represents the energy recovery rate (%); E in Indicates the system input energy / kJ·m -3 E out Indicates the system output energy / kJ·m -3 .

[0026] Process complexity is derived by calculating the number of critical processes in the experimental flow. System volume is derived by calculating the actual spatial volume of the system device.

[0027] Satisfaction value X hi X refers to the highest level that the i-th evaluation indicator may reach during the evaluation calculation process; values ​​of X are not allowed. si The satisfaction value X represents the lowest level that the i-th evaluation indicator should not reach during the evaluation calculation process. hi and the disallowed value X si This was obtained by consulting references and combining them with practical experience.

[0028] Single-item efficacy coefficient d i Based on the satisfaction value X hi and the disallowed value X si Calculate and obtain the single-item effectiveness coefficient d i Divided into four categories, namely, extremely large indicators d1i Minimal index d 2i Stable index d 3i and interval type indicator d 4i Among them, the extremely large indicator d 1i This represents the single-item efficacy coefficient of the i-th extreme evaluation indicator. Here, extreme evaluation indicator refers to a variable whose single-item efficacy coefficient is higher the larger the indicator value (actual value). Extreme indicator d 1i The calculation formula is as follows:

[0029]

[0030] Minimal indicator d 2i This represents the individual efficacy coefficient of the i-th minimal evaluation indicator. Here, a minimal evaluation indicator refers to a variable whose individual efficacy coefficient is higher the smaller the indicator value (actual value). Minimal indicator d 2i The calculation formula is as follows:

[0031]

[0032] Stable index d 3i This represents the single-item efficacy coefficient of the i-th stable evaluation indicator. Here, a stable evaluation indicator refers to the variable whose single-item efficacy coefficient value is the highest at a certain point. Stable indicator d 3i The calculation formula is as follows:

[0033]

[0034] Interval indicator d 4i This represents the single-item efficacy coefficient of the i-th interval-type evaluation indicator; here, an interval-type evaluation indicator refers to the variable whose single-item efficacy coefficient value is the highest when the indicator value is within a certain interval. Interval-type indicator d 4i The calculation formula is as follows:

[0035]

[0036] In the formula, X i X represents the actual value of the i-th evaluation indicator; min X represents the lower limit value of the i-th interval variable index; max X represents the upper limit of the i-th interval variable index; s min This represents the lower limit of the unacceptable values ​​for the i-th interval-type variable indicator; X h max This represents the upper limit satisfaction value of the i-th interval variable index.

[0037] Weighting coefficient f iThe weighting coefficient f is used to quantitatively reflect the importance of the corresponding evaluation indicators and is calculated using the coefficient of variation method in the objective weighting method. Specifically, the weighting coefficient f i The calculation formula is as follows:

[0038]

[0039] In the formula, m represents the number of evaluation indicators; z i Let represent the coefficient of variation of the i-th evaluation index, calculated as follows:

[0040]

[0041] In the formula, σ i This represents the standard deviation of the i-th evaluation index; This represents the average value of the i-th evaluation indicator.

[0042] Step 2, based on the weighting coefficient f of each evaluation indicator i and single-item efficacy coefficient d i Calculate the overall efficiency coefficient (EC) of the target microalgae-microorganism fuel cell system; the calculation formula is as follows:

[0043]

[0044] Based on the obtained total efficiency coefficient (EC), the system with the highest EC in the constructed comparison system is selected (this system has the best overall performance and the highest energy utilization rate). For systems with lower EC (below the set value), the system is searched for indicators that combine high individual efficiency coefficient values ​​(e.g., for very small indicators, low coefficients are needed; for very large indicators, high coefficients are needed) and high weighting coefficients. This indicator is the most critical indicator determining the system's performance. Further, the indicator is analyzed to identify the process parameters affecting it, such as illumination and circulating pumps. Subsequently, experimental control groups under different operating conditions are set up and included in the sample. The evaluation system is used to re-evaluate the samples to determine the optimal operating conditions, thereby achieving optimized control of the system's operating strategy.

[0045] The target system for a microalgae-microorganism fuel cell of this invention includes: a column-type photobioreactor body, an aeration device, an LED lighting system, and an optimization subsystem. The aeration device is located at the bottom center of the column-type photobioreactor body and is connected to an external air supply device for aeration. The LED lighting system is located on the outer periphery of the column-type reactor, providing the necessary light source for microalgae growth. Both the aeration device and the LED lighting system are conventional components of microalgae-microorganism fuel cells. This invention differentiates the target system through the optimization subsystem. This optimization subsystem can be located inside the algal solution in the reactor or outside the reactor. Its function is to optimize and improve the system's solution environment, CO2 dissolution / conversion, gas-liquid mass transfer / mixing, microalgae growth / carbon fixation, and overall system performance.

[0046] To verify the evaluation and screening methods of this invention, six different forms of microalgae-microorganism fuel cell hybrid systems were constructed. These six systems were named PBR, PBR-OS-PC, PBR-MOFs, PBR-MFC, PBR-MFC-SOC, and C-MFC@PBR, respectively. Their main features and application scenarios are as follows: Figure 2 As shown in Table 1.

[0047] Table 1 shows six different combinations of hybrid systems constructed in this invention.

[0048]

[0049]

[0050] Furthermore, in this embodiment of the invention, the column photobioreactor is an airlift column photobioreactor, with a total height of 30-50cm and a diameter of 15-25cm.

[0051] The turbulence component includes a flow guide tube that is suspended and coaxially integrated within the main body of the column-type photobioreactor. The outer wall of the tube is provided with several rows of staggered ribs from top to bottom. The ribs are fan-shaped, and the included angle between two adjacent ribs in each row is 30 to 45°. The vertical distance between the ribs in each row is 1.5 to 3.0 cm.

[0052] MOF nanoparticles, including Zn / Fe-MOF nanoparticles, were prepared by a room-temperature co-precipitation-high-temperature pyrolysis process. The zinc / iron molar ratio in the precursor was 0–20, and the concentration of the nanoparticles was 0–10 mg·L⁻¹. -1 .

[0053] MFC, including air cathode MFC, is made of plexiglass, with a length, width, and height of 10–15 cm, 6–8 cm, and 6–8 cm respectively. It has an internal cylindrical chamber with a diameter of 2–5 cm, and a total effective volume of 10–50 cm³. 3 .

[0054] MFC-SOC consists of an air cathode MFC and an oxygen-consuming biofilm SOC. The SOC is composed of activated carbon felt and microalgae biofilm. The thickness of the SOC is 0.1 to 2.0 cm. The entire cathode chamber of the MFC-SOC is light-shielded.

[0055] C-MFC is made of acrylic glass, with an inner diameter of 8–12 cm and a height of 15–20 cm. The effective volume of C-MFC is 500–600 cm³. 3 The cathode is surrounded by hydrophobic carbon cloth, with an oxygen reduction catalyst coating on one side and a PTFE breathable and waterproof coating on the other. The anode is a carbon brush with a diameter of 3-8 cm and a height of 4-6 cm.

[0056] This invention provides a comprehensive performance evaluation and screening method based on the efficacy coefficient method for evaluating and screening the above six systems. The main steps include:

[0057] (1) Evaluation index X i Acquisition

[0058] The overall performance of a microalgae-microorganism fuel cell hybrid system involves multiple factors, such as carbon sequestration efficiency, power generation, footprint, investment cost, energy recovery rate, and process complexity. This invention, through extensive literature review and practical measurement, selected four parameters—carbon sequestration efficiency, energy recovery rate, number of processes, and system volume—as evaluation indicators to fully reflect the system's overall performance characteristics. Using the aforementioned six typical systems as a sample, a comprehensive performance evaluation system based on the efficiency coefficient method was constructed. Information on the different evaluation indicators for the six systems is shown in Table 2.

[0059] Table 2. Measured values ​​of evaluation indicators for six energy systems in the sampled samples.

[0060] 1 PBR 15.95 17.19 2 <![CDATA[3.13×10 -2 ]]> 2 PBR-OS-PC 24.40 21.54 3 <![CDATA[3.13×10 -2 ]]> 3 PBR-MOFs 21.57 21.03 3 <![CDATA[3.13×10 -2 ]]> 4 PBR-MFC 20.70 18.49 3 <![CDATA[3.44×10 -2 ]]> 5 PBR-MFC-SOC 26.71 24.11 3 <![CDATA[3.44×10 -2 ]]> 6 C-MFC@PBR 26.98 28.73 3 <![CDATA[3.13×10 -2 ]]>

[0061] (2) Evaluation index satisfaction value X hi and the disallowed value X si Acquisition

[0062] Based on the above six hybrid systems, the sampling sample S was first determined. a1 As shown in the following formula. Secondly, through literature review, the satisfactory and unacceptable values ​​of the four evaluation indicators were determined. These two indicators correspond to the highest level that should be achieved and the lowest level that should not be achieved, respectively, as shown in Table 3.

[0063]

[0064] Table 3 Key Parameter Information for Evaluation Indicators

[0065]

[0066]

[0067] (3) Evaluation index: single-item efficacy coefficient d i Acquisition

[0068] In the efficiency coefficient method's index system, due to the various relationships between the indicators and individual efficiency coefficients, these indicators can be divided into four categories: extremely large indicators (the larger the indicator value, the higher the individual efficiency coefficient value), extremely small indicators (the smaller the indicator value, the higher the individual efficiency coefficient value), stable indicators (the individual efficiency coefficient value is highest at a certain point), and interval indicators (the individual efficiency coefficient value is highest when the indicator value is within a certain interval). The evaluation system of this invention includes two extremely large indicators (carbon sequestration efficiency and energy recovery rate) and two extremely small indicators (number of processes and system volume).

[0069] Based on the sampled S a1 The average value and standard deviation of each evaluation index were calculated, and then combined with the satisfactory value and the unacceptable value. The experimental data are shown in Table 4.

[0070] Table 4. Individual efficacy coefficient values ​​of each system evaluation indicator

[0071] PBR 0.68 0.64 0.94 0.88 PBR-OS-PC 0.75 0.67 0.89 0.88 PBR-MOFs 0.73 0.66 0.89 0.88 PBR-MFC 0.72 0.65 0.89 0.86 PBR-MFC-SOC 0.76 0.68 0.89 0.86 C-MFC@PBR 0.77 0.71 0.89 0.88

[0072] (4) Evaluation index weight coefficient f i Acquisition

[0073] The weight of an evaluation indicator within the overall system can quantitatively reflect its importance. To more objectively and accurately predict the overall benefits of the system, this invention uses the coefficient of variation method in the objective weighting method to calculate the weight coefficient of the indicator.

[0074] The calculation results are shown in Table 5. It can be seen that the weights of the four evaluation indicators in this sample are in the following order: energy recovery rate > carbon sequestration efficiency > number of processes > system volume. This indicates that energy recovery rate is the most critical parameter in the system.

[0075] Table 5 Comparison of the weight coefficients of the evaluation indicators

[0076] 1 Carbon fixation efficiency / % 22.72 <![CDATA[3.83×10 -2 ]]> <![CDATA[1.69×10 -1 ]]> 0.32 great 2 Energy recovery rate / % 21.85 <![CDATA[3.79×10 -2 ]]> <![CDATA[1.74×10 -1 ]]> 0.33 great 3 Number of processes / units 2.83 <![CDATA[3.73×10 -1 ]]> <![CDATA[1.32×10 -1 ]]> 0.25 extremely small 4 <![CDATA[System volume / m 3 > <![CDATA[3.23×10 -2 ]]> <![CDATA[1.46×10 -3 ]]> <![CDATA[4.53×10 -2 ]]> 0.10 extremely small

[0077] (5) Obtaining the total effectiveness coefficient (EC) of the target object

[0078] Based on the evaluation system constructed in this invention, the total efficacy coefficient (EC) of six different hybrid systems was calculated, such as... Figure 3As shown in the figure. The results indicate that, in the aforementioned hybrid systems, C-MFC@PBR, by eliminating the circulating pump, not only simplifies the process and reduces input energy consumption but also improves internal gas-liquid mass transfer / flow mixing conditions, demonstrating the best overall performance. For the various indicators of other systems, the power consumption coefficient can be calculated using the evaluation model constructed in this invention. The experimental conditions corresponding to indicators with lower power consumption coefficients can be further optimized, thereby enabling flexible and efficient selection of system performance.

[0079] In summary, the comprehensive performance evaluation and screening method for microalgae-microorganism fuel cell hybrid bioenergy systems proposed in this invention can objectively, comprehensively, and quantitatively evaluate the overall performance of this type of energy system, thereby providing theoretical support for guiding practical engineering applications.

Claims

1. A method for evaluating and screening the comprehensive performance of a microalgae-microorganism fuel cell system, characterized in that, Includes the following steps: Step 1, obtain the evaluation indicators, and the... i Satisfaction value of each evaluation indicator X hi Disallowed values X si Single-item efficacy coefficient d i and weighting coefficients f i The evaluation indicators include microalgae carbon fixation efficiency, energy recovery rate, process complexity, and system volume; the satisfaction value... X hi Refers to the first i The highest level that each evaluation indicator may reach during the evaluation calculation process, the unacceptable value. X si Refers to the first i The minimum level that each evaluation indicator should not reach during the evaluation calculation process; the individual efficacy coefficient d i According to the satisfaction value X hi and the not allowed value X si Calculated and obtained; the weighting coefficient f i It is used to quantitatively reflect the importance of the corresponding evaluation indicators, and is calculated using the coefficient of variation method; Step 2, based on the weighting coefficients of each evaluation indicator f i and single-item efficacy coefficient d i Calculate the overall efficiency coefficient of the target system of microalgae-microorganism fuel cell. EC ; EC The largest target system has the best overall performance and the highest energy efficiency. for EC For systems below the set value, we look for indicators among all evaluation indicators that have both high single-item efficacy coefficients and high weight coefficients. These indicators are the most critical indicators that determine the performance of the system. Then, we analyze the indicators to determine the process parameters that affect them. Subsequently, we set up experimental control groups under different operating conditions and included them in the sample for inspection. We then use the evaluation system to evaluate the samples again to determine the optimal operating conditions, thereby achieving the optimization and control of the system operation strategy.

2. The method for evaluating and screening the comprehensive performance of the microalgae-microorganism fuel cell system according to claim 1, characterized in that, The formula for calculating the carbon fixation efficiency of microalgae is as follows: In the formula, CRE Indicates microalgae carbon fixation efficiency (%). C min Indicates the concentration of imported CO2; C mout Indicates the CO2 concentration at the outlet; The energy recovery rate is calculated as follows: In the formula, η Indicates energy recovery; E in Indicates the system's input energy; E out Indicates the system's output energy; The process complexity is obtained by calculating the number of key processes in the experimental procedure; The system volume is obtained by calculating the actual spatial volume of the system device.

3. The method for evaluating and screening the comprehensive performance of the microalgae-microorganism fuel cell system according to claim 1 or 2, characterized in that, The single-item efficacy coefficient d i Divided into four categories, namely, extremely large indicators d 1i Minimal Indicators d 2i Stable indicators d 3i and interval indicators d 4i Among them, extremely large indicators d 1i Indicates the first i The individual efficacy coefficient of a very large evaluation indicator, and the efficiency coefficient of a very small indicator. d 2i Indicates the first i Individual efficacy coefficients of extremely small evaluation indicators, stable indicators d 3i Indicates the first i Individual efficacy coefficients of stable evaluation indicators, and interval indicators d 4i Indicates the first i The individual efficacy coefficient of each interval-type evaluation indicator; The term "extremely large evaluation index" refers to a variable whose larger value corresponds to a higher single-item efficacy coefficient; the term "extremely small evaluation index" refers to a variable whose smaller value corresponds to a higher single-item efficacy coefficient; the term "stable evaluation index" refers to a variable whose single-item efficacy coefficient is highest at a certain point; and the term "interval evaluation index" refers to a variable whose single-item efficacy coefficient is highest at a certain interval.

4. The method for evaluating and screening the comprehensive performance of the microalgae-microorganism fuel cell system according to claim 3, characterized in that, The extremely large indicators d 1i The calculation formula is as follows: The extremely small index d 2i The calculation formula is as follows: The stability index d 3i The calculation formula is as follows: The interval-type indicator d 4i The calculation formula is as follows: In the formula, X i Indicates the first i The actual values ​​of each evaluation indicator; X min Indicates the first i The lower limit of an interval-type variable indicator; X max Indicates the first i The upper limit of an interval-type variable indicator; X smin Indicates the first i The lower limit of an interval-type variable indicator is not allowed to be a certain value; X hmax Indicates the first i The upper limit of the satisfactory value of an interval-type variable indicator.

5. The method for evaluating and screening the comprehensive performance of the microalgae-microorganism fuel cell system according to claim 4, characterized in that, The weighting coefficient f i The calculation formula is as follows: In the formula, m Indicates the number of evaluation indicators; z i Indicates the first i The coefficient of variation for each evaluation indicator is calculated as follows: In the formula, σ i Indicates the first i The standard deviation of each evaluation indicator; Indicates the first i The average value of each evaluation indicator.

6. The method for evaluating and screening the comprehensive performance of the microalgae-microorganism fuel cell system according to claim 5, characterized in that, The overall efficiency coefficient EC The calculation formula is as follows: 。 7. The method for evaluating and screening the comprehensive performance of the microalgae-microorganism fuel cell system according to claim 1, characterized in that, The target system for the microalgae-microorganism fuel cell includes: Main body of column-type photobioreactor; An aeration device is installed at the bottom center of the main body of the column-type photobioreactor and is connected to an external air supply device for aeration. An LED lighting system is installed on the outer ring of the column reactor to provide the necessary light source for microalgae growth; Optimize the subsystem, either inside the algal solution in the reactor or outside the reactor, to optimize and improve the overall performance of the system.

8. The method for evaluating and screening the comprehensive performance of the microalgae-microorganism fuel cell system according to claim 7, characterized in that, The optimized subsystem may be a built-in turbulence component, or a built-in MOF nanoparticle, or an external MFC, or an external oxygen-consuming biofilm optimized microbial fuel cell MFC-SOC, or an embedded column-type microbial fuel cell C-MFC.

9. The method for evaluating and screening the comprehensive performance of the microalgae-microorganism fuel cell system according to claim 8, characterized in that, The turbulence-inducing component includes a drainage tube suspended and coaxially integrated within the main body of the column-type photobioreactor. The outer wall of the tube has several rows of staggered ribs arranged from top to bottom. The ribs are fan-shaped, and the included angle between adjacent ribs in each row is 30-45 degrees. o The vertical spacing between each row of ribs is 1.5~3.0 cm; The MOF nanoparticles, including Zn / Fe-MOF nanoparticles, are prepared by a room-temperature co-precipitation-high-temperature pyrolysis process. The zinc / iron molar ratio in the precursor is 0–20, and the concentration of the nanoparticles is 0–10 mg·L⁻¹. -1 ; The MFC includes an air cathode MFC made of plexiglass, with a length, width, and height of 10-15 cm, 6-8 cm, and 6-8 cm, respectively. It has an internal cylindrical chamber with a diameter of 2-5 cm and a total effective volume of 10-50 cm³. 3 ; The MFC-SOC includes an air cathode MFC and an oxygen-consuming biofilm SOC. The SOC is composed of activated carbon felt and microalgae biofilm. The thickness of the SOC is 0.1~2.0 cm. The cathode chamber of the entire MFC-SOC is light-shielded. The C-MFC is made of plexiglass, with an inner diameter of 8-12 cm, a height of 15-20 cm, and an effective volume of 500-600 cm³. 3 The cathode is surrounded by hydrophobic carbon cloth, with an oxygen reduction catalyst coating on one side and a PTFE breathable and waterproof coating on the other side. The anode is a carbon brush with a diameter of 3~8 cm and a height of 4~6 cm.

Images