Fused salt energy storage power generation system using biomass

Abstract

The invention discloses a power generation system for fused salt energy storage by using biomass. According to the system, the purity of raw materials is remarkably improved through an intelligent sorting and impurity removing unit of the pretreatment and coupling module, the waste heat driving drying unit effectively recycles system waste heat to reduce energy consumption, the flexible forming unit generates biomass fuel with stable physical characteristics, and the nano-catalysis pretreatment unit optimizes the reaction activity of the fuel on the molecular level. The measures directly improve the integrity of biomass combustion and the heat energy conversion efficiency, so that the fuel of unit mass releases more effective heat in the fused salt combustor. Meanwhile, tar is decomposed from the source through catalytic pretreatment, generation of nitric oxide and sulfur oxide precursors is reduced, the treatment load of a follow-up flue gas purification system is greatly reduced, the whole system reduces dependence on external energy on the basis of ensuring stable power supply through collaborative optimization of fuel pretreatment, stored energy release and clean emission, and the energy-saving and environment-friendly effects are achieved. And a high-adaptability solution is provided for distributed energy supply.

Description

Technical Field

[0001] The present invention belongs to the technical field of molten salt power generation, and specifically relates to a molten salt energy storage power generation system utilizing biomass. Background Art

[0002] Molten salt energy storage power generation is an advanced clean energy technology that uses molten salt as an energy storage medium, storing excess heat energy in the molten salt during the solar or other energy generation process. The high boiling point and low melting point of molten salt enable it to store large amounts of heat energy at high temperatures and release it when needed. When grid demand increases or solar energy is insufficient, the stored heat energy is used to generate steam to drive turbines for electricity generation. This technology not only improves energy utilization efficiency but also enhances the stability and reliability of the grid. Especially in areas with abundant solar resources, molten salt energy storage power generation can provide continuous and stable power output, reduce dependence on traditional fossil fuels, and help achieve a green transformation of the energy structure.

[0003] However, existing technologies generally have core defects such as extensive fuel pretreatment leading to low combustion efficiency, broken waste heat recovery chain causing energy waste, heavy end-of-pipe pollutant treatment load increasing operating costs, and unstable physical and chemical properties of fuel affecting system response speed. Summary of the Invention

[0004] The purpose of the present invention is to provide a molten salt energy storage and power generation system using biomass in order to solve the above-mentioned problems.

[0005] The technical solution adopted by the present invention is as follows: a molten salt energy storage and power generation system using biomass, the system comprising: a pretreatment and coupling module, a high-efficiency molten salt burner module, a molten salt heat storage and heat exchange module, a steam turbine power generation module, a flue gas purification and treatment module, and a control system and energy management module;

[0006] The interior of the pretreatment and coupling module is equipped with: an intelligent sorting and impurity removal unit, a waste heat driven drying unit, a flexible molding unit and a nanocatalytic pretreatment unit;

[0007] The precise metering delivery port of the pretreatment and coupling module is connected to the biomass fuel inlet of the high-efficiency molten salt burner module through a closed screw feeder;

[0008] The high-temperature molten salt outlet of the high-efficiency molten salt burner module is directly connected to the high-temperature storage tank inlet of the molten salt heat storage and heat exchange module through an insulated pipe, and its flue gas outlet is connected to the inlet flue of the flue gas purification and treatment module.

[0009] The molten salt inlet of the steam generator of the molten salt heat storage and heat exchange module is connected to the high-temperature storage tank outlet via a high-temperature molten salt pump, and the steam outlet generated by the generator is connected to the air inlet valve of the steam turbine power generation module through the main steam pipeline;

[0010] The cooling water outlet of the condenser of the steam turbine power generation module is branched to the inlet of the waste heat drying unit heat exchanger of the pre-treatment module, and the exhaust steam outlet is connected to the condenser inlet.

[0011] The purified gas outlet of the flue gas purification and treatment module is connected to the chimney via an induced draft fan;

[0012] The signal acquisition ends of the control system and energy management module are distributed throughout the key nodes of each module, and their control instruction output ends are respectively connected to the catalyst metering pump of the pretreatment module, the molten salt flow control valve of the burner module, the molten salt pump inverter of the heat storage module, the turbine regulating valve of the power generation module, and the ammonia injection controller of the purification module.

[0013] In a preferred embodiment, the intelligent sorting and impurity removal unit adopts multimodal sensor fusion technology, including a high-speed visible light camera (resolution ≥ 8MP), a near-infrared spectrometer (wavelength range 900-1700nm), a metal detection array (sensitivity ≤Φ1mm iron) and a laser profile scanner (accuracy ±0.1mm). The raw materials are separated by a vibrating screen and then enter a closed conveyor belt. The visible light camera is used to identify organic / inorganic impurities (such as plastics and stones) based on HSV color space segmentation. The near-infrared spectrum is used to analyze the cellulose / lignin characteristic peak (1590cm) in real time through the PLS regression model. -1 ,1160cm -1 ) distinguishes biomass types. The metal detection array uses eddy current phase locking technology to locate metal impurities, and the laser profilometer calculates volume density and detects abnormal protrusions through point cloud fitting. Multi-source data is input into the FPGA embedded system, and a confidence-weighted fusion algorithm outputs sorting decisions, driving the high-pressure air injection valve (response time <10ms) to accurately remove impurities.

[0014] The calculation formula of the multimodal confidence weighted fusion algorithm is:

[0015]

[0016] Where:

[0017] M c Indicates the final fusion confidence (scalar value, range [0,1]), which is used to trigger the impurity removal action;

[0018] w i Represents the dynamic weight coefficient of the i-th sensor (satisfying ∑w i =1), updated by the online learning model based on historical sorting accuracy;

[0019] S i represents the normalized output of the i-th sensor (S i∈[0,1]), after feature extraction, it is mapped by Sigmoid function;

[0020] Δ ti represents the delay between the sensor data of type i and the reference timestamp (unit: milliseconds);

[0021] τ represents the time decay constant (the default value is τ = 15.0), which controls the impact of timeliness on confidence. n represents the number of valid sensors involved in fusion, n = 4.

[0022] In a preferred embodiment, the waste heat driven drying unit adopts a multi-stage heat recovery architecture, integrating the medium and low temperature hot salt pipeline discharged from the molten salt system or the turbine exhaust steam waste heat pipeline as the primary heat source. The heat source is indirectly heat exchanged with the drying air flow through a high-efficiency plate heat exchanger. The drying air is driven by a variable frequency centrifugal fan and flows through the biomass packed bed drying chamber. The drying chamber is designed as a multi-stage vibrating screen plate structure to ensure uniform heating and air permeability of the material. The real-time monitoring system deploys a capacitive humidity sensor array to measure the moisture distribution on the biomass surface, and a non-contact infrared temperature sensor array to scan the material temperature field. The data acquisition module transmits the signal to the embedded microcontroller, which runs a control strategy based on an adaptive fuzzy proportional integral differential algorithm to dynamically optimize the hot air flow set value and the heat exchanger valve opening. The goal is to stably control the moisture content of the biomass within the range of 10 to 15. At the same time, a waste heat recovery efficiency monitor is provided inside the unit to adjust the waste heat utilization rate through a feedback loop to maximize the overall energy efficiency of the system and prevent the risk of overheating.

[0023] The adaptive feedforward compensation control output formula is:

[0024]

[0025] Where:

[0026] u t Indicates the control output, dimensionless, ranging from 0 to 1, indicating the opening of the hot air control valve or the set ratio of the fan speed;

[0027] K p Represents the proportional gain coefficient, dimensionless, and is calibrated offline according to the system response characteristics;

[0028] e t Represents the humidity error, defined as e t =H set -H meast , where H set is the target moisture content setting value, H meast Measure the moisture content at the current moment;

[0029] K i Represents the integral gain coefficient, dimensionless, used to eliminate steady-state error;

[0030] K d It represents the differential gain coefficient, dimensionless, which suppresses humidity fluctuations;

[0031] e˙t represents the rate of change of humidity error, i.e. det / dt, in units of one second;

[0032] λ represents the feedforward gain coefficient, dimensionless, and is adaptively updated through the online learning algorithm;

[0033] ΔT src Indicates the temperature change of the waste heat source in degrees Celsius, calculated as T srct -T src0 , where T srct is the current waste heat temperature, T src0 is the baseline waste heat temperature.

[0034] In a preferred embodiment, the flexible molding unit comprises three physical processing stages. The first stage is a pre-compression screw feeder with a variable-pitch twin-screw structure, offering an adjustable screw speed range of 50 to 200 rpm. A capacitive level sensor is installed at the inlet to monitor the bulk density of the biomass chips in real time. The second stage is the core compression molding chamber, equipped with a hydraulically servo-driven, high-strength mold assembly. The compression ratio is dynamically adjustable from 8:1 to 15:1, maintaining a compression pressure between 80 and 120 MPa. A diamond-like carbon coating is deposited on the mold surface to reduce the friction coefficient to below 0.1. A laser diameter gauge is installed at the outlet to continuously monitor the diameter of the molded bar to a tolerance of ±0.5 mm. The third stage is a forced cooling conveyor section, equipped with a copper water-cooling coil in direct contact with the molded bar. The cooling water flow is controlled by a closed-loop thermocouple to ensure that the bar surface temperature drops from 120°C to below 40°C within 10 seconds. A load cell array is installed at the end to calculate the production capacity per unit time.

[0035] In a preferred embodiment, the nanocatalytic pretreatment unit comprises four functional subsystems. The first is a catalyst suspension preparation system, comprising storage tanks for transition metal nitrate and alkali metal carbonate solutions, calibrated to 1.2 mol / L and 0.8 mol / L, respectively. A precision metering pump delivers 0.5 to 5 ml per gram of biomass into a static mixer to generate the nanocomposite suspension. The second is a two-fluid atomization device, employing an air-assisted nozzle with optimized internal flow channels. The compressed air pressure is 0.7 MPa, liquid flow fluctuation is less than ±2%, and the atomized particle size distribution D50 is stabilized at 8 microns. The nozzle array spacing is dynamically adjusted based on the feed rate of the forming bar. The third is an ultrasonically assisted penetration section, equipped with a 20 kHz piezoelectric transducer array. The acoustic intensity density is set to 15 watts per square centimeter, and the action time is precisely controlled within a range of 3 to 5 seconds. The penetration depth detection module uses a beta-ray densitometer for real-time feedback. The fourth layer is the catalytic layer quality monitoring module, which integrates an X-ray fluorescence spectrometer to analyze the uniformity of catalyst element distribution online. The detection cycle is less than 30 seconds, and the data is transmitted to the central controller via industrial Ethernet.

[0036] In a preferred embodiment, the high-efficiency molten salt burner module is internally provided with a three-stage combustion structure. The first stage is a biomass pre-combustion chamber equipped with a cyclone-type air distributor with an air volume adjustment accuracy of ±2%. It is equipped with a high-energy plasma igniter to ensure cold start reliability. The second stage is the core molten salt contact reaction section, which is lined with silicon carbide-based composite refractory materials and has a maximum temperature tolerance of 1200 degrees Celsius. The molten salt injection system is equipped with sixteen sets of symmetrically arranged atomizing nozzles, maintaining an atomization pressure of 0.8 MPa, and the molten salt flow control valve has an adjustment accuracy of ±0.5 liters per minute. The third stage is a flue gas rapid cooling mixing chamber, which is equipped with a porous ceramic flow plate to reduce the flue gas turbulence intensity. A K-type thermocouple array is embedded in the cavity wall to monitor the wall temperature gradient in real time.

[0037] In a preferred embodiment, the molten salt heat storage and exchange module is equipped with a dual-tank independent temperature control system. The high-temperature storage tank utilizes a double-layer stainless steel shell structure, with an inner layer made of S31008 stainless steel and an outer carbon steel insulation shell. The middle layer is insulated with a nano-aerogel layer. The tank is equipped with four sets of electric heating cables for anti-condensation. The molten salt circulation pipeline is equipped with a two-stage centrifugal pump group, with a single pump flow rate of 120 cubic meters per hour and a head of 60 meters. Metal bellows compensators are installed at the inlet and outlet to absorb thermal expansion displacement. The steam generator adopts a countercurrent shell and tube heat exchange structure. The heat exchange tubes are made of Inconel 625 alloy with a wall thickness of 2.5 mm. The tube bundles are arranged in a 30-degree triangle layout, and the shell-side steam pressure is designed to be 13.7 MPa.

[0038] In a preferred embodiment, the steam turbine power generation module houses a single-cylinder reheat turbine body with seventeen stages of reaction blades. The first six stages are constructed from TD-NiCrAl high-temperature alloy, and the rotor is a solidly forged chromium-molybdenum-vanadium steel. The accompanying condenser utilizes a dual-flow surface heat exchange structure, with cooling tubes constructed from titanium alloy Gr.2, and a total heat exchange area of ​​6,800 square meters. The vacuum maintenance system features a two-stage water ring vacuum pump. The generator utilizes a fully enclosed hydrogen cooling structure, with Class F insulation for the stator windings. Distributed temperature sensors are installed on the rotor poles, and bearing vibration monitoring utilizes eddy current displacement probes.

[0039] In a preferred embodiment, the flue gas purification and treatment module is internally equipped with four treatment sections. The first-stage high-temperature electrostatic precipitator has a plate spacing of 400 mm, an operating temperature of 350 degrees Celsius, and a dust removal efficiency of ≥99.5%. The second-stage semi-dry desulfurization tower adopts a rotary atomizer structure, with an atomizing disk speed of 12,000 rpm and a lime slurry solid content controlled at 25%. The third-stage medium- and low-temperature SCR denitrification reactor is equipped with a honeycomb catalyst module. The main component of the catalyst is V2O5-WO3 / TiO2, and the ammonia injection grid is equipped with 128 independent spray guns. The fourth-stage metal filter cartridge dust collector has a filtration accuracy of 0.3 microns, the filter material is an iron-aluminum intermetallic compound, and the pulse backflushing pressure is 0.6 MPa.

[0040] In a preferred embodiment, the control system and energy management module are internally configured with a three-tiered redundant control architecture. The first tier comprises field-level distributed I / O stations with 2,876 data points, utilizing PROFIBUS-DP transmission and a 100-millisecond scan cycle. The second tier comprises a process-level controller group configured with three industrial servers for hot standby redundancy and a real-time database with a 1-second storage cycle. The third tier comprises a plant-level energy management computer, equipped with a mixed-integer linear programming algorithm core that updates a 96-hour economic dispatch plan every five minutes. The critical protection system utilizes a triple voting mechanism, achieving a safety response time of less than 50 milliseconds.

[0041] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0042] 1. In this invention, the intelligent sorting and impurity removal units of the pretreatment and coupling modules significantly improve feedstock purity. The waste heat-driven drying unit effectively recovers system waste heat and reduces energy consumption. The flexible molding unit produces biomass fuel with stable physical properties. The nanocatalytic pretreatment unit optimizes fuel reactivity at the molecular level. These measures directly improve the integrity of biomass combustion and thermal energy conversion efficiency, allowing more effective heat to be released per unit mass of fuel in the molten salt burner. Furthermore, the catalytic pretreatment decomposes tar at the source and reduces the formation of nitrogen oxide and sulfur oxide precursors, significantly reducing the processing load of the subsequent flue gas purification system.

[0043] 2. In this invention, integrated pretreatment imparts controllable combustion characteristics to biomass fuels. Combined with the flexible buffering capacity of molten salt heat storage, the system can rapidly respond to fluctuations in grid demand. Improved combustion efficiency and source control of pollutants reduce operating costs, while the cascaded utilization of waste heat further enhances overall energy efficiency. Through the coordinated optimization of fuel pretreatment, stored energy release, and clean emissions, the entire system reduces reliance on external energy sources while ensuring stable power supply, providing a highly adaptable solution for distributed energy supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 is a block diagram of the overall system of the present invention;

[0045] Figure 2 This is a system block diagram of the preprocessing and coupling modules in the present invention. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0047] Example:

[0048] Reference Figure 1-2 ,

[0049] A molten salt energy storage and power generation system using biomass, the system includes: a pretreatment and coupling module, a high-efficiency molten salt burner module, a molten salt heat storage and heat exchange module, a steam turbine power generation module, a flue gas purification and treatment module, and a control system and energy management module;

[0050] The pretreatment and coupling module is internally equipped with: intelligent sorting and impurity removal unit, waste heat driven drying unit, flexible molding unit and nano-catalytic pretreatment unit;

[0051] The precise metering delivery port of the pretreatment and coupling module is connected to the biomass fuel inlet of the high-efficiency molten salt burner module through a closed screw feeder;

[0052] The high-temperature molten salt outlet of the high-efficiency molten salt burner module is directly connected to the high-temperature storage tank inlet of the molten salt heat storage and heat exchange module through an insulated pipe, and its flue gas outlet is connected to the inlet flue of the flue gas purification and treatment module.

[0053] The molten salt inlet of the steam generator of the molten salt heat storage and heat exchange module is connected to the outlet of the high-temperature storage tank through a high-temperature molten salt pump, and the steam outlet generated by the generator is connected to the air inlet valve of the steam turbine power generation module through the main steam pipeline;

[0054] The cooling water outlet of the condenser of the steam turbine power generation module is diverted to the inlet of the waste heat drying unit heat exchanger of the pre-treatment module, and its exhaust steam outlet is connected to the condenser inlet.

[0055] The purified gas outlet of the flue gas purification and treatment module is connected to the chimney through the induced draft fan;

[0056] The signal acquisition ends of the control system and energy management module are spread across the key nodes of each module, and their control instruction output ends are respectively connected to the catalyst metering pump of the pretreatment module, the molten salt flow control valve of the burner module, the molten salt pump inverter of the heat storage module, the turbine regulating valve of the power generation module, and the ammonia injection controller of the purification module.

[0057] The intelligent sorting and impurity removal unit uses multimodal sensor fusion technology, including a high-speed visible light camera (resolution ≥ 8MP), a near-infrared spectrometer (wavelength range 900-1700nm), a metal detection array (sensitivity ≤Φ1mm iron) and a laser profile scanner (accuracy ±0.1mm). After being stratified by the vibrating screen, the raw materials enter the closed conveyor belt. The visible light camera identifies organic / inorganic impurities (such as plastics and stones) based on HSV color space segmentation, and the near-infrared spectrum uses the PLS regression model to analyze the cellulose / lignin characteristic peaks (1590cm -1 ,1160cm -1 ) distinguishes biomass types. The metal detection array uses eddy current phase locking technology to locate metal impurities, and the laser profilometer calculates volume density and detects abnormal protrusions through point cloud fitting. Multi-source data is input into the FPGA embedded system, and a confidence-weighted fusion algorithm outputs sorting decisions, driving the high-pressure air injection valve (response time <10ms) to accurately remove impurities.

[0058] The calculation formula of the multimodal confidence weighted fusion algorithm is:

[0059]

[0060] Where:

[0061] M c Indicates the final fusion confidence (scalar value, range [0,1]), which is used to trigger the impurity removal action;

[0062] w i Represents the dynamic weight coefficient of the i-th sensor (satisfying ∑w i =1), updated by the online learning model based on historical sorting accuracy;

[0063] S i represents the normalized output of the i-th sensor (S i ∈[0,1]), after feature extraction, it is mapped by Sigmoid function;

[0064] Δ ti represents the delay between the sensor data of type i and the reference timestamp (unit: milliseconds);

[0065] τ represents the time decay constant (the default value is τ = 15.0), which controls the influence of timeliness on confidence. n represents the number of valid sensors involved in fusion, n = 4.

[0066] The waste heat-driven drying unit adopts a multi-stage heat recovery architecture, integrating the medium- and low-temperature hot salt pipeline discharged from the molten salt system or the turbine exhaust steam waste heat pipeline as the primary heat source. The heat source indirectly exchanges heat with the drying air flow through a high-efficiency plate heat exchanger. The drying air is driven by a variable frequency centrifugal fan and flows through the biomass-packed bed drying chamber. The drying chamber is designed with a multi-stage vibrating screen plate structure to ensure uniform heating and air permeability of the material. The real-time monitoring system deploys a capacitive humidity sensor array to measure the moisture distribution on the biomass surface and a non-contact infrared temperature sensor array to scan the material temperature field. The data acquisition module transmits the signal to the embedded microcontroller, which runs a control strategy based on an adaptive fuzzy proportional integral differential algorithm to dynamically optimize the hot air flow setpoint and the heat exchanger valve opening. The goal is to stably control the biomass moisture content within the range of 10 to 15. At the same time, a waste heat recovery efficiency monitor is installed inside the unit. The waste heat utilization rate is adjusted through a feedback loop to maximize the overall energy efficiency of the system and prevent the risk of overheating.

[0067] The adaptive feedforward compensation control output formula is:

[0068]

[0069] Where:

[0070] u t Indicates the control output, dimensionless, ranging from 0 to 1, indicating the opening of the hot air control valve or the set ratio of the fan speed;

[0071] K p Represents the proportional gain coefficient, dimensionless, and is calibrated offline according to the system response characteristics;

[0072] e t Represents the humidity error, defined as e t =H set -H meast , where H set is the target moisture content setting value, H meast Measure the moisture content at the current moment;

[0073] K i Represents the integral gain coefficient, dimensionless, used to eliminate steady-state error;

[0074] K d It represents the differential gain coefficient, dimensionless, which suppresses humidity fluctuations;

[0075] e˙t represents the rate of change of humidity error, i.e. det / dt, in units of one second;

[0076] λ represents the feedforward gain coefficient, dimensionless, and is adaptively updated through the online learning algorithm;

[0077] ΔT src Indicates the temperature change of the waste heat source in degrees Celsius, calculated as T srct -T src0 , where T srct is the current waste heat temperature, T src0 is the baseline waste heat temperature.

[0078] The flexible molding unit features three physical processing stages. The first stage is a pre-compression screw feeder with a variable-pitch twin-screw structure, offering an adjustable screw speed range of 50 to 200 rpm. A capacitive level sensor at the inlet monitors the bulk density of the biomass chips in real time. The second stage is the core compression molding chamber, equipped with a hydraulically servo-driven, high-strength die assembly. The compression ratio is dynamically adjustable from 8:1 to 15:1, maintaining a compression pressure between 80 and 120 MPa. A diamond-like carbon coating is deposited on the die surface to reduce the coefficient of friction to below 0.1. A laser diameter gauge at the outlet continuously monitors the diameter of the finished bar to a tolerance of ±0.5 mm. The third stage is a forced cooling conveyor section, equipped with a copper water-cooling coil in direct contact with the finished bar. The cooling water flow is controlled by a closed-loop thermocouple to ensure that the bar surface temperature drops from 120°C to below 40°C within 10 seconds. A load cell array is installed at the end to calculate the production capacity per unit time.

[0079] The nanocatalytic pretreatment unit is comprised of four functional subsystems. The first is the catalyst suspension preparation system, consisting of storage tanks for transition metal nitrate and alkali metal carbonate solutions, calibrated to 1.2 mol / L and 0.8 mol / L, respectively. Precision metering pumps deliver 0.5 to 5 ml / g of biomass into a static mixer to generate the nanocomposite suspension. The second is a two-fluid atomization device, employing an air-assisted nozzle with optimized internal flow channels. Compressed air pressure is 0.7 MPa, resulting in a liquid flow rate fluctuation of less than ±2% and a stable atomized particle size distribution (D50) of 8 microns. The nozzle array spacing is dynamically adjusted based on the feed rate of the forming bar. The third is the ultrasonically assisted penetration section, equipped with a 20 kHz piezoelectric transducer array. The acoustic intensity density is set to 15 watts per square centimeter, and the action time is precisely controlled within a range of 3 to 5 seconds. The penetration depth measurement module uses a beta-ray densitometer for real-time feedback. The fourth is the catalyst layer quality monitoring module, integrating an X-ray fluorescence spectrometer for online analysis of catalyst element uniformity. The measurement cycle is less than 30 seconds, and data is transmitted to a central controller via industrial Ethernet.

[0080] The high-efficiency molten salt burner module features a three-stage combustion structure. The first stage is a biomass pre-combustion chamber equipped with a cyclonic air distributor with an air volume adjustment accuracy of ±2%. A high-energy plasma igniter ensures cold start reliability. The second stage is the core molten salt contact reaction section, lined with a silicon carbide-based composite refractory material and capable of withstanding temperatures up to 1200°C. The molten salt injection system features sixteen symmetrically arranged atomizing nozzles, maintaining an atomization pressure of 0.8 MPa. The molten salt flow control valve has an adjustment accuracy of ±0.5 liters per minute. The third stage is a flue gas quenching mixing chamber, equipped with a porous ceramic flow plate to reduce flue gas turbulence intensity. An array of K-type thermocouples embedded in the chamber wall monitors the wall temperature gradient in real time.

[0081] The molten salt heat storage and heat exchange module features a dual-tank independent temperature control system. The high-temperature storage tank utilizes a double-layer stainless steel shell, with an inner layer made of S31008 stainless steel and an outer carbon steel insulation shell. The middle layer is insulated with nano-aerogel. The tank is equipped with four sets of electric heating cables for anti-condensation. The molten salt circulation pipeline is equipped with a two-stage centrifugal pump unit, with a single pump design flow rate of 120 cubic meters per hour and a head of 60 meters. Metal bellows compensators are installed at the inlet and outlet to absorb thermal expansion displacement. The steam generator utilizes a countercurrent shell-and-tube heat exchange structure. The heat exchange tubes are made of Inconel 625 alloy with a wall thickness of 2.5 mm. The tube bundles are arranged in a 30-degree triangle layout, and the shell-side steam pressure is designed to be 13.7 MPa.

[0082] The steam turbine generator module houses a single-cylinder reheat turbine with seventeen stages of reaction blades. The first six stages are constructed from TD-NiCrAl high-temperature alloy, while the rotor is a solidly forged chromium-molybdenum-vanadium steel. The accompanying condenser utilizes a dual-pass surface heat exchange structure with cooling tubes made from titanium alloy Gr.2, providing a total heat exchange area of ​​6,800 square meters. The vacuum maintenance system features a two-stage water-ring vacuum pump. The generator utilizes a fully enclosed hydrogen cooling system, with Class F insulation for the stator windings. Distributed temperature sensors are installed on the rotor poles, and bearing vibration monitoring utilizes eddy current displacement probes.

[0083] The flue gas purification and treatment module features four treatment stages. The first-stage high-temperature electrostatic precipitator has a plate spacing of 400 mm, an operating temperature of 350°C, and a dust removal efficiency of ≥99.5%. The second-stage semi-dry desulfurization tower utilizes a rotary atomizer with an atomizing disk speed of 12,000 rpm and a lime slurry solids content controlled at 25%. The third-stage medium- and low-temperature SCR denitrification reactor features a honeycomb catalyst module composed primarily of V2O5-WO3 / TiO2. The ammonia injection grid is equipped with 128 independent spray guns. The fourth-stage metal cartridge filter has a filtration accuracy of 0.3 microns, using an iron-aluminum intermetallic compound as the filter material and a pulse backflushing pressure of 0.6 MPa.

[0084] The control system and energy management module utilize a three-tiered redundant control architecture. The first tier consists of field-level distributed I / O stations with 2,876 data points, using PROFIBUS-DP transmission and a 100-millisecond scan cycle. The second tier comprises process-level controllers, configured with three industrial servers for hot standby redundancy and a real-time database with a 1-second storage cycle. The third tier comprises a plant-level energy management computer, equipped with a mixed-integer linear programming algorithm core that updates the 96-hour economic dispatch plan every five minutes. Key protection systems utilize a triple voting mechanism, ensuring a safety response time of less than 50 milliseconds.

[0085] From the above we can know:

[0086] In this invention, the intelligent sorting and impurity removal units of the pretreatment and coupling modules significantly improve feedstock purity. The waste heat-driven drying unit effectively recovers system waste heat and reduces energy consumption. The flexible molding unit produces biomass fuel with stable physical properties. The nanocatalytic pretreatment unit optimizes fuel reactivity at the molecular level. These measures directly improve the integrity of biomass combustion and the efficiency of thermal energy conversion, allowing more effective heat to be released per unit mass of fuel in the molten salt burner. Furthermore, the catalytic pretreatment decomposes tar at the source and reduces the production of nitrogen oxide and sulfur oxide precursors, significantly reducing the processing load of the subsequent flue gas purification system.

[0087] In this invention, integrated pretreatment imparts controllable combustion characteristics to biomass fuels. Combined with the flexible buffering capacity of molten salt heat storage, the system can rapidly respond to fluctuations in grid demand. Improved combustion efficiency and source control of pollutants reduce operating costs, while the cascaded utilization of waste heat further enhances overall energy efficiency. Through the coordinated optimization of fuel pretreatment, stored energy release, and clean emissions, the entire system reduces reliance on external energy sources while ensuring stable power supply, providing a highly adaptable solution for distributed energy supply.

[0088] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprises" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further limitations, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device that includes the element.

[0089] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A molten salt energy storage and power generation system using biomass, characterized by: The system includes: a pretreatment and coupling module, a high-efficiency molten salt burner module, a molten salt heat storage and heat exchange module, a steam turbine power generation module, a flue gas purification and treatment module, and a control system and energy management module; The interior of the pretreatment and coupling module is equipped with: an intelligent sorting and impurity removal unit, a waste heat driven drying unit, a flexible molding unit and a nanocatalytic pretreatment unit; The precise metering delivery port of the pretreatment and coupling module is connected to the biomass fuel inlet of the high-efficiency molten salt burner module through a closed screw feeder; The high-temperature molten salt outlet of the high-efficiency molten salt burner module is directly connected to the high-temperature storage tank inlet of the molten salt heat storage and heat exchange module through an insulated pipe, and its flue gas outlet is connected to the inlet flue of the flue gas purification and treatment module; The molten salt inlet of the steam generator of the molten salt heat storage and heat exchange module is connected to the high-temperature storage tank outlet via a high-temperature molten salt pump, and the steam outlet generated by the generator is connected to the air inlet valve of the steam turbine power generation module through the main steam pipeline; The cooling water outlet of the condenser of the steam turbine power generation module is diverted to the inlet of the waste heat drying unit heat exchanger of the pre-treatment module, and its exhaust steam outlet is connected to the condenser inlet; The purified gas outlet of the flue gas purification and treatment module is connected to the chimney via an induced draft fan; The signal acquisition ends of the control system and energy management module are distributed throughout the key nodes of each module, and their control instruction output ends are respectively connected to the catalyst metering pump of the pretreatment module, the molten salt flow control valve of the burner module, the molten salt pump inverter of the heat storage module, the turbine regulating valve of the power generation module, and the ammonia injection controller of the purification module.

2. The molten salt energy storage and power generation system using biomass as claimed in claim 1, characterized in that: The intelligent sorting and impurity removal unit includes a high-speed visible light camera, a near-infrared spectrometer, a metal detection array, and a laser profiler. After being stratified by a vibrating screen, the raw materials enter a closed conveyor belt. The visible light camera identifies organic and inorganic impurities based on HSV color space segmentation. The near-infrared spectrometer uses a PLS regression model to analyze cellulose and lignin characteristic peaks in real time to distinguish biomass types. The metal detection array uses eddy current phase locking technology to locate metal impurities. The laser profiler calculates volume density and detects abnormal protrusions through point cloud fitting. Multi-source data is input into the FPGA embedded system, and a confidence-weighted fusion algorithm is used to output sorting decisions, driving the high-pressure air injection valve to accurately remove impurities. The calculation formula of the multimodal confidence weighted fusion algorithm is: Where: M c Indicates the final fusion confidence, which is used to trigger the impurity removal action; w i represents the dynamic weight coefficient of the i-th sensor, which is updated by the online learning model based on the historical sorting accuracy; S i represents the normalized output of the i-th sensor, which is mapped by the Sigmoid function after feature extraction; Δ ti represents the delay between the sensor data of type i and the reference timestamp; τ represents the time decay constant, which controls the intensity of the influence of timeliness on confidence; n represents the number of effective sensors involved in fusion, n=4.

3. The molten salt energy storage and power generation system using biomass as claimed in claim 1, characterized in that: The waste heat driven drying unit is provided with a medium- and low-temperature hot salt pipeline discharged from the molten salt system or a turbine exhaust steam waste heat pipeline as a primary heat source. The heat source is indirectly heat exchanged with the drying air flow through a high-efficiency plate heat exchanger. The drying air is driven by a variable frequency centrifugal fan and flows through the biomass packed bed drying chamber. The drying chamber is designed as a multi-section vibrating screen plate structure to ensure uniform heating and air permeability of the material. The real-time monitoring system deploys a capacitive humidity sensor array to measure the moisture distribution on the biomass surface, and a non-contact infrared temperature sensor array to scan the material temperature field. The data acquisition module transmits the signal to the embedded microcontroller. The microcontroller runs a control strategy based on an adaptive fuzzy proportional integral differential algorithm to dynamically optimize the hot air flow set value and the heat exchanger valve opening. The goal is to stably control the moisture content of the biomass within the range of 10 to 15. At the same time, a waste heat recovery efficiency monitor is provided inside the unit to adjust the waste heat utilization rate through a feedback loop to maximize the overall energy efficiency of the system and prevent overheating risks. The adaptive feedforward compensation control output formula is: Where: u t Indicates the control output, dimensionless, ranging from 0 to 1, indicating the opening of the hot air control valve or the set ratio of the fan speed; K p Represents the proportional gain coefficient, dimensionless, and is calibrated offline according to the system response characteristics; e t Represents the humidity error, defined as e t =H set -H meast , where H set is the target moisture content setting value, H meast Measure the moisture content at the current moment; K i Represents the integral gain coefficient, dimensionless, used to eliminate steady-state error; K d It represents the differential gain coefficient, dimensionless, which suppresses humidity fluctuations; e˙t represents the rate of change of humidity error, i.e. det / dt, in units of one second; λ represents the feedforward gain coefficient, dimensionless, and is adaptively updated through the online learning algorithm; ΔT src Indicates the temperature change of the waste heat source in degrees Celsius, calculated as T srct -T src0 , where T srct is the current waste heat temperature, T src0 is the baseline waste heat temperature.

4. The molten salt energy storage and power generation system using biomass as claimed in claim 1, characterized in that: The flexible forming unit is equipped with three physical treatment layers. The first stage is a pre-compression screw feeder with a variable pitch twin-screw structure. The screw speed range is adjustable from 50 to 200 revolutions per minute. A capacitive material level sensor is configured at the inlet to monitor the bulk density of the biomass fragments in real time. The second stage is the core compression molding cavity, which is equipped with a high-strength mold group driven by a hydraulic servo. A laser diameter gauge is installed at the outlet to continuously monitor the diameter tolerance of the molded bar and control it within ±0.5 mm; the third stage is the forced cooling conveying section, which is equipped with a copper water-cooling coil inside that is in direct contact with the molded bar, and the cooling water flow is controlled by a thermocouple closed loop.

5. The molten salt energy storage and power generation system using biomass as claimed in claim 1, characterized in that: The nanocatalytic pretreatment unit is internally provided with four functional subsystems. The first layer is a catalyst suspension preparation system, which includes a transition metal nitrate solution storage tank and an alkali metal carbonate solution storage tank; The second layer is a dual-fluid atomization application device, which uses an air-assisted nozzle with optimized internal flow channel, a compressed air pressure of 0.7 MPa, a liquid flow fluctuation of less than ±2%, a stable atomization particle size distribution D50 value of 8 microns, and the nozzle array spacing is dynamically adjusted according to the conveying speed of the forming rod; the third layer is an ultrasonic-assisted penetration section, which is equipped with a 20 kHz piezoelectric transducer array, the sound intensity density is set to 15 watts per square centimeter, and the action time is precisely controlled in the range of 3 to 5 seconds.

6. The molten salt energy storage and power generation system using biomass as claimed in claim 1, characterized in that: The interior of the high-efficiency molten salt burner module is equipped with a three-stage combustion structure. The first stage is a biomass precombustion chamber equipped with a cyclone separation air distributor with an air volume adjustment accuracy of ±2%. It is equipped with a high-energy plasma igniter to ensure cold start reliability; the second stage is the core molten salt contact reaction section, which is lined with silicon carbide-based composite refractory materials. The third stage is a flue gas rapid cooling mixing chamber, which is equipped with a porous ceramic flow equalizing plate to reduce the flue gas turbulence intensity. A K-type thermocouple array is embedded in the cavity wall to monitor the wall temperature gradient in real time.

7. The molten salt energy storage and power generation system using biomass as claimed in claim 1, characterized in that: The molten salt heat storage and heat exchange module is equipped with a dual-tank independent temperature control system. The high-temperature storage tank adopts a double-layer stainless steel shell structure. The inner layer is made of S31008 stainless steel, the outer layer is a carbon steel insulation shell, and the middle is filled with a nano-aerogel insulation layer. The tank body is equipped with four sets of electric heating tape anti-condensation systems; the molten salt circulation pipeline is equipped with a two-stage centrifugal pump group. The single pump flow design value is 120 cubic meters per hour and the head is 60 meters. The inlet and outlet are equipped with metal bellows compensators to absorb thermal expansion displacement.

8. The molten salt energy storage and power generation system using biomass as claimed in claim 1, characterized in that: The steam turbine power generation module is internally provided with a single-cylinder reheat steam turbine body, which includes seventeen stages of reaction blades. The first six stages of blades are made of TD-NiCrAl high-temperature alloy, and the rotor is made of a solidly forged chromium-molybdenum-vanadium steel forging; the matching condenser adopts a double-flow surface heat exchange structure, the cooling pipe is made of titanium alloy Gr.2, the total heat exchange area is 6,800 square meters, and the vacuum maintenance system is equipped with a two-stage water ring vacuum pump; the generator adopts a fully enclosed hydrogen cooling structure, the stator winding insulation grade is F, the rotor poles are equipped with distributed temperature sensors, and the bearing vibration monitoring uses an eddy current displacement probe.

9. The molten salt energy storage and power generation system using biomass as claimed in claim 1, characterized in that: The flue gas purification and treatment module is internally equipped with four treatment sections. The first-stage high-temperature electrostatic precipitator has a plate spacing of 400 mm, an operating temperature of 350 degrees Celsius, and a dust removal efficiency of ≥99.5%; the second-stage semi-dry desulfurization tower adopts a rotary atomizer structure, the atomizing disk speed is 12,000 revolutions per minute, and the solid content of the lime slurry is controlled at 25%; the third-stage medium- and low-temperature SCR denitrification reactor is arranged with a honeycomb catalyst module; the fourth-stage metal filter cartridge dust collector has a filtration accuracy of 0.3 microns, and the filter material is an iron-aluminum intermetallic compound.

10. The molten salt energy storage and power generation system using biomass according to claim 1, characterized in that: The control system and energy management module are internally configured with a three-tier redundant control architecture. The first tier is the field-level distributed I / O station, with a total of 2,876 acquisition points, using PROFIBUS-DP bus transmission and a scan cycle of 100 milliseconds. The second tier is the process-level controller group, configured with three industrial servers for hot standby redundancy, and a real-time database storage cycle of 1 second. The third layer is the plant-level energy management computer, which has a mixed integer linear programming algorithm core inside.

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