157 results about "Cascade" patented technology

The invention provides an online monitoring device for multiple nuclides in liquid effluent, and particularly relates to the technical field of radioactive substance detection. The online monitoring device comprises a shell, a cascade separation module, a fluid control module, a detection module and a control system, the cascade separation module, the detection module and the control system are arranged in the shell, the cascade separation module comprises a plurality of resin columns and a plurality of separated liquid collecting bottles communicated with the resin columns, and the separated liquid collecting bottles are communicated with the resin columns. The fluid control module comprises a liquid storage device, an injection pump and a control valve, the liquid storage device is respectively communicated with the plurality of resin columns through pipelines, the injection pump and the control valve are respectively arranged on the pipelines and are used for controlling the flow direction and the flow velocity of fluid in the liquid storage device, and the detection module is used for detecting the radioactive activity of nuclide; the control system is used for controlling operation of the cascade separation module, the fluid control module and the detection module. According to the invention, synchronous monitoring of multiple nuclides is realized, the multi-nuclide monitoring efficiency is improved, and the monitoring cost is reduced.

The invention provides a multi-nuclide automatic separation and detection system and method, and particularly relates to the technical field of radioactive substance detection. The detection system comprises a cascade separation and regeneration unit, a dynamic regulation and control unit, an online detection unit, an eluent conveying unit and a control system, and the eluent conveying unit is matched with the cascade separation and regeneration unit to separate and purify radionuclide and regenerate resin. The dynamic regulation and control unit is used for controlling a flow path between the eluent conveying unit and the cascade separation regeneration unit and feeding back changes of pressure, temperature and pH value in the flow path in real time, and the online detection unit is used for detecting concentration of nuclides in separation liquid and feeding back monitoring data to the control system. And the control system controls the operation of each functional unit and automatically plans a separation path according to a measurement requirement to form a separation-detection-optimization closed-loop process. The device is suitable for the fields of nuclear facility liquid effluent detection, environmental water radioactivity detection and the like, and has high efficiency, environmental protection property and intelligence.

The invention discloses a cascade control method and system for the alum adding process of a waterworks. The cascade control method comprises the steps that preprocessed operation data of the waterworks are obtained; according to the preprocessed operation data, on the basis of a pre-trained LSTM-Transformer prediction model, an alum adding amount prediction value, an effluent turbidity prediction value and a sedimentation velocity prediction value at the current moment are obtained; segmenting the alumen ustum image based on an SAM algorithm, extracting features by adopting OpenCV, and calculating a settling velocity; based on feed-forward-feedback compound control, the feed-forward control adjusts the alum adding amount in time by monitoring the change of the quality of raw water, a main loop of cascade control predicts the water turbidity through MPC to calculate the optimal set value of the settling velocity, an auxiliary loop calculates the alum adding amount through the settling velocity, the feed-forward control and cascade control are subjected to decentralized summation, and the alum adding amount is calculated according to the optimal set value of the settling velocity. And calculating the final addition amount of the alum. According to the invention, the dosage of alum can be regulated and controlled more accurately.

The invention relates to a cascade reservoir group water storage scheduling method under an extra-low water condition, which comprises the following steps of: judging whether a cascade reservoir group has a risk of insufficient storage according to incoming water prediction, a minimum water level constraint, a minimum output flow constraint and a water storage target of each reservoir at the end of a water storage period, and if so, starting the cascade reservoir group water storage scheduling under the extra-low water condition; taking the minimum weighted sum of the difference between the highest water level of the cascade reservoir group in the scheduling period and the water storage target as a first scheduling target, taking the maximum sum of the generating capacity and the energy storage value of the cascade reservoir group as a second scheduling target, and establishing a cascade reservoir group water storage scheduling model without setting the end water level of the scheduling period; and solving to obtain a scheduling scheme with the maximum water storage satisfaction degree of the cascade reservoir group. The method can be used for coordinating the water storage processes of all the reservoirs under the ultra-low water condition, the cascade reservoirs can complete the water storage task to the maximum extent, and the overall cascade power generation benefits are considered.

The invention relates to the technical field of powder batching monitoring, and discloses a fixed-value batching method and system for a powder material, and the method comprises the steps: carrying out the dynamic correction of a spiral servo and a stirring motor through a cascade PID control and time prediction feedforward control method; on-line self-adaptive adjustment of key batching parameters in the fixed-value batching process of the powder material can be achieved, the fixed-value batching precision is improved, the productivity is improved, the pollution risk caused by manual supplement and the like due to out-of-tolerance in the production process is reduced, and the production efficiency is improved.

The invention discloses a method for enriching < 7 > Li through electrodialysis coupling extraction, which comprises the following steps of: connecting a plurality of functional membranes in series and coupling for enriching < 7 > Li through electrodialysis, respectively placing a supply phase and a receiving phase on two sides of the functional membranes, and adjusting the volume ratio of the supply phase to the receiving phase to be (1-100): (1-100) by controlling the flow rates of the supply phase and the receiving phase through PID (Proportion Integration Differentiation), and electrifying the electrodes on the two sides of the plurality of functional membranes which are connected in series, applying voltage with the voltage of-20 to 20V for 3 seconds to 120 minutes, and extracting and separating the Li isotope. According to the method, the Li isotope is subjected to cascade separation through an electrodialysis coupling membrane technology, so that the selectivity of 7Li is increased, the separation and enrichment effect of the 7Li isotope is improved, and the abundance of the 7Li natural stable isotope can be improved from 92.47% to 5N level through 102-level cascade.

The invention discloses a tracking control method and system for a cascade type continuous stirring reaction kettle time delay system under a state dependence constraint, and belongs to the technical field of automatic control. The method comprises the following steps: acquiring a nonlinear time-lag system model, constrained by state dependence, of a cascade type continuous stirred tank time-lag system based on a mechanism model of the cascade type continuous stirred tank time-lag system; obtaining a time-varying asymmetric Lyapunov function of the cascaded continuous stirred tank reactor based on the nonlinear time-delay system model; and based on the time-varying asymmetric Lyapunov function and the Lyapunov-Krasovski function, obtaining a controller of the continuous stirred tank reactor, and performing tracking control on the cascaded continuous stirred tank reactor through the controller. According to the method, a nonlinear time delay system model subjected to state dependence constraint is taken as a basis, and the influence of time-varying time delay and state dependence constraint on the system performance is eliminated by combining a time-varying asymmetric Lyapunov function and a Lyapunov-Crasovski function.

The invention belongs to the technical field of uranium concentration, and particularly relates to an online debugging system and method for a regulating valve of a uranium concentration factory. The system comprises at least two raw material containers, at least three block valves and at least one purification material receiving container, the at least two raw material containers are mutually connected in parallel and are respectively connected to the feeding main pipe loop line through independent branch pipelines; the feeding main pipe loop line is connected with the centrifugal cascade; each branch pipeline is connected in series with a regulating valve; uranium hexafluoride gas is stored in the at least two raw material containers; at least three block valves are connected in series on the feeding main pipe loop line and are respectively positioned between two adjacent raw material containers and between the raw material containers and the centrifugal cascade; and the purifying and collecting container is respectively connected with an outlet of each raw material container through a feeding and purifying pipeline. The regulating valve can be debugged and verified online by using a uranium hexafluoride medium, so that the problem that real working conditions cannot be simulated due to great difference from actual working conditions when static and dynamic debugging and verification are performed offline by using an air medium is solved.

The invention discloses a method for evaluating the water storage level of a cascade reservoir, and relates to the technical field of reservoir dispatching. The evaluation method comprises the following steps: acquiring related basic data of the cascade reservoir; determining a water storage scheduling period and a calculation period of the cascade reservoir; obtaining the water storage capacity of each calculation time period of each reservoir in the water storage scheduling period over the years; calculating the overall water storage capacity of the cascade reservoir in each calculation period of the water storage scheduling period of the cascade reservoir year by year, and obtaining the annual minimum to-be-stored capacity in all the calculation periods of the water storage scheduling period of the cascade reservoir year by year; constructing a distribution function of the annual minimum storage capacity of the cascade reservoir; and constructing a cascade reservoir water storage level evaluation system. The method has the advantages of being simple, convenient, practical, reasonable, reliable, easy to popularize and the like, an index system for dynamically evaluating the water storage level of the cascade reservoir is constructed according to the adjusting capacity, the incoming water situation and the water storage state of the cascade reservoir, the current water storage level of the cascade reservoir can be rapidly evaluated, and a future dispatching operation strategy is guided.

The embodiment of the invention provides an extractive distillation system, a control method and an extractive distillation process, and belongs to the technical field of chemical separation and purification. The extractive distillation system comprises an extractive distillation tower, a first condenser, a first reboiler, a first reflux tank, an extraction agent recovery tower, a second condenser, a second reboiler, a second reflux tank, a raw material preheater, a plurality of regulating valves, a plurality of material conveying pumps and control equipment, the control equipment comprises a first pressure controller, a second pressure controller, a first reflux tank liquid level controller, a first reboiler liquid level controller, a second reflux tank liquid level controller, a second reboiler liquid level controller, a first reflux ratio controller, a first cascade control loop and a second cascade control loop, a third cascade control loop and a fourth cascade control loop. The extractive distillation system has the technical effect of improving the purity of the obtained product.

The invention relates to a preparation method and application of a cascade reactor based on 2D MOF. According to the method, a regular layered MOFs material is prepared by adjusting the molar ratio and concentration of different metal salts to ligands, then the material is soaked in an ethanol and isopropanol solvent, the material is activated through ultrasonic waves in an ice-water bath, layered separation is achieved through intermolecular force, a 2D MOFs material with the micron-scale size and the nano-scale thickness is obtained, finally, SOX is added, and the 2D MOFs material with the micron-scale size and the nano-scale thickness is obtained. The method comprises the following steps: carrying out a two-dimensional (2D) MOF / SOX cascade reactor to obtain a two-dimensional (2D) MOF / SOX cascade reactor capable of constructing a colorimetric sensor with TMB (3, 3 ', 5, 5'-tetramethyl benzidine). The reactor can perform 1-400 [mu] M linear quantification on sarcosine, and LOD is 0.324 [mu] M. According to the invention, high-efficiency, simple and cheap Pca capable of being rapidly detected can be synthesized without complex synthesis processes, instruments and expensive precious metals.

The invention provides a float-discrete differential dynamic programming successive approximation method for cascade reservoir group scheduling, comprising the following steps: water levels of cascade reservoir group are raised from small to large according to water surface areas of reservoirs; the cascade reservoir group generates electricity after raising the water level according to incoming water; at the end of calculation period, and initial water level trajectory is obtained when the raised water level of the cascade reservoir group falls back to the set water level; based on the initial water level trajectory obtained, discrete differential dynamic programming calculation of each reservoir is carried out from upstream to downstream with the goal of maximizing the cascade total power generation, and the improved water level trajectory of each cascade reservoir is obtained; taking the improved water level trajectory of each cascade reservoir as the initial trajectory, and the iterative optimization is carried out.

The application provides a cascade reservoir group storage and discharge dynamic coordination matching scheduling optimization method and system, and relates to the technical field of water conservancy and hydropower engineering, wherein the method comprises: obtaining the storage capacity of each reservoir in the cascade reservoir group at the current time and the designed storage capacity, and calculating the current fullness rate of each reservoir; for each pair of adjacent reservoirs in the cascade reservoir group, based on the current fullness rate of each adjacent reservoir and the preset joint regulation capacity coefficient, a weighted relative difference value representing the difference degree of the fullness rate of the adjacent reservoirs is calculated; based on the weighted relative difference values of all adjacent reservoir pairs, the coordination matching degree of the cascade reservoir group is determined. Through the application, accurate quantification, dynamic tracking and early warning of scheduling coordination are realized, and the scientificity and timeliness of scheduling decisions are improved.

A method and cascade reactor system for producing elemental rare earth metals and rare earth-aluminum alloys via aluminothermic reduction are disclosed. The method involves combining rare earth oxides or halide salts with aluminum powder, initiating a thermite-type reaction under inert or controlled atmospheric conditions, and recovering the molten metal product. Fluxing agents may be used to enhance slag fluidity and phase separation. The cascade reactor comprises multiple thermite zones with staged ignition, thermal transfer mechanisms, and slag separation interfaces, enabling sequential reduction of mixed feedstocks. The system supports both batch and continuous formats and achieves high recovery yields, reduced aluminum contamination, and compatibility with alloying and post-purification processes. The invention is adaptable to individual rare earth species and mixed oxide concentrates, offering a scalable, energy-efficient, and environmentally favorable route to rare earth metal and alloy production.

According to the ginseng extraction system and method provided by the invention, the dual goals of high purity and high yield of ginsenoside extraction are achieved through raw material adaptive parameter pre-optimization, self-adaptive cascade purification and activity protection, the enrichment effect of high-value monomer saponin is remarkable, and the loss of active ingredients is accurately controlled. According to the application, a detection-decision-regulation full-process closed-loop intelligent control system is constructed, near infrared spectrum rapid screening and HPLC-MS / MS accurate quantitative dual-mode online detection are fused, real-time and accurate monitoring of the saponin content is realized, and off-line detection and artificial experience parameters are not needed; the multi-target central control unit can automatically decide a purification path and process parameters according to detection data, and designs such as membrane pollution on-line monitoring, automatic backwashing and solvent circulating preheating are combined, so that continuous operation of the process is ensured, and production interruption caused by equipment failure and process fluctuation is avoided.

The present application relates to the technical fields of chemical synthesis, and discloses a kind of aviation kerosene production process and equipment, production process includes: carbon source gas, hydrogen, circulating gas is sent into main reactor reaction and obtains including hydrocarbon, methanol, CO, water and unreacted gas mixed component a;Mixed component a is sent into cascade reactor and is prepared to obtain including aviation kerosene component, light hydrocarbon component and water mixed component b, wherein light hydrocarbon component includes one or more of C2-C7 light hydrocarbon;Mixed component b is fractionally condensed to collect liquid phase and gas phase, and liquid phase is carried out three-phase separation to obtain aviation kerosene component, light hydrocarbon component and water respectively, aviation kerosene component is hydrotreated, fractionation to obtain aviation kerosene.The present application realizes the step-by-step control of reaction path in carbon source hydrogenation process through the synergistic effect of main reactor and cascade reactor, improves the selectivity of aviation kerosene target product, so that the obtained product meets the 3# aviation kerosene standard requirements in key indicators such as distillation range distribution, aromatic content and low temperature performance.

The object of the present invention is to provide a stable isotope enrichment method that can reduce equipment costs and power without lengthening the start-up time and can achieve efficient enrichment. The present invention provides a stable isotope enrichment method, which is a method for separating stable isotopes using a plurality of distillation columns (the first column to the m-th column; m is an integer of 2 or more) connected in cascade. One of gas and liquid is supplied from a position near the bottom of the (n-1)-th column to a position near the top of the n-th column (1 < n ≤ m), and the other of gas and liquid is returned from a position near the top of the n-th column to a position near the bottom of the (n-1)-th column. In each distillation column, when the flow rate of the gas rising in the column is set as the first flow rate and the flow rate of the gas or liquid supplied from the previous column or the next column is set as the second flow rate, the second flow rate is set to 4% by volume or more of the first flow rate.

The invention relates to the technical field of nano cerium oxide production, in particular to a self-collision dispersion process without destroying the morphology of nano cerium oxide, which comprises the following steps: S1, material pretreatment: S1.1, impurity removal treatment: according to production requirements, obtaining a cerium carbonate / cerium silicate raw material, then crushing the cerium carbonate / cerium silicate raw material by air flow until D50 is 3-5 microns, then putting into a nitric acid solution for ultrasonic cleaning, and drying to obtain a cerium oxide / cerium silicate powder; neutralizing with ammonia water until the pH value is 6.0 + / -0.5, centrifugally separating, weighing the material, and ensuring that the purity of the cerium compound in the raw material is greater than or equal to 99.9%; according to the method, the dispersing-drying-magnetizing-calcining multi-stage joint control technology is adopted, the technological process is shortened, the efficiency is improved, the viscosity of homogeneous slurry is controlled through high-speed dispersing and synchronous stepped vacuum drying, secondary agglomeration is avoided, segmented calcining is combined with nitrogen-hydrogen mixed gas and the nucleating agent, lattice defects can be reduced, energy consumption can be reduced, and the method is suitable for large-scale production. Automatic parameter matching is achieved through magnetic field-flow velocity formulation linkage, the impact precision is improved, and the process stability is remarkably improved.

The invention discloses a rapid programmable generation device and method for a cascade droplet array. The device comprises a hydrophobic fan-shaped substrate, a scraper blade, a radially arranged hydrophilic stack point array and a driving device. Driving the mother liquid drops to move along the surface of the hydrophobic substrate through the rotation of the scraper, and dividing the mother liquid drops into micro-droplets residing in a hydrophilic area by utilizing the surface tension difference between the hydrophilic stack point and the hydrophobic substrate; the liquid drop volume is dynamically controlled by adjusting the rotating speed of the scraper blade or the diameter gradient distribution of the stack points, and the gradient liquid drop array is generated through single operation. The device does not need an external pump valve or a precise sealing device, has the advantages of open type passive operation, low cost, high flux, high stability and the like, is suitable for scenes of drug screening, single cell analysis, instant detection and the like, and remarkably improves the flexibility of micro-droplet generation and the experiment efficiency.

A product-activity-tunable method for calcining a carbonate mineral, relating to a method for calcining a carbonate mineral. In the present invention, two stages of reactions (i.e., a carbonate decomposition reaction and a product high-temperature sintering reaction) of a carbonate calcination process are separated in two reactors, i.e., a carbonate decomposition reactor and an activity tunning reactor, and the activity of products is flexibly regulated and controlled by respectively controlling the reaction conditions of the two reactors, thereby achieving co-production of multiple active products, and solving the problems of traditional production technologies, e.g., single product activity and limited product application. In addition, high-temperature flue gas from the activity tunning reactor is used as a heat source for the carbonate decomposition reactor, achieving efficient cascade utilization of energy in a system, and achieving significant energy saving and consumption reduction effects. In addition, the production process takes only a few seconds to a few minutes, the system processing capacity is high, and large-scale industrialization is easy to achieve.

A reactor apparatus comprising a reactor vessel 32, media conditioning circuit 34 and a fluid flow controller 36 wherein the fluid flow controller allows the flow of fluid through the reactor vessel to be reversed. The external fermentation broth loop has conditioning modules 50 52 that may alter pH, temperature, gases, or remove waste products. The fluid flow controller may reverse the flow automatically at intermittent periods, and may be a pump or valve. In an alternative configuration, there is a media and cell separation device 42 44 that retains cells inside the reactor vessel, allowing circulation of reaction media between the bioreactor and media loop. The cells may be separated from the media through a filter or membrane, or mechanically separated by gravity or centrifugation. Additionally, there may be several reactor vessels that are connected in a cascading (430, Fig 5) or parallel (330, Fig 5) arrangement. A method of operating the reactor apparatus is also disclosed.

The invention provides a transformer oil acetylene degassing-free detection method and system based on click chemistry, and relates to the technical field of gas detection analysis, a first product generated by a first click chemical reaction and a second product generated by a second click chemical reaction are used as catalysts to trigger a subsequent same cascade chemical amplification reaction, and the detection result is accurate. A single product molecule can catalytically hydrolyze a large number of acid-sensitive substrates, the conductivity of a mixed solution is obvious and can be measured and changed, accurate detection of acetylene with extremely low concentration is realized, and meanwhile, acetylene detection is calculated by utilizing a second click chemical reaction synchronously generated by an internal standard reagent and a triggering agent and independent of an acetylene concentration detection process, so that the accuracy of acetylene detection is improved. According to the method, the signal ratio is obtained by calculating the ratio of the first electric signal value to the second electric signal value instead of the single first electric signal value, interference factors are offset, online self-correction of acetylene detection is realized, and high consistency and accuracy of detection results under different times and different batches of reagents are ensured.

The invention related to a cascaded reactor system (10) and a method for carrying out an endothermic reaction from a fed reactive mixture stream characterized in that comprising a plurality of reactor shells (20) serially connected each having at least one reactive stream duct (22), a stream inlet (25) for receiving the fed reactive mixture stream, a stream outlet (26), a catalyst section (21) provided inside said reactive stream duct (22) between said stream inlet (25) and stream outlet (26), an insulation filling (60) at least partly encompassing said reactive stream duct (22), a ceramic catalyst bed (30) accommodated in said catalyst section (21), where the reactive mixture stream undergoing a catalytic reaction, electrical heating means (40) for heating said structured ceramic catalyst bed (30) up to a predetermined reaction temperature, at least two electrical feeds (51) passing through the inlet section connected to an electrical power supply (50) provided outside of the reactive stream duct (22), wherein the inlet section of at least one pressure vessel contains a separating device for creating a cold section within the inlet zone of said reactor shell (20).

A lead-cooled fast reactor system and control method. The system includes a core control system and a steam generator control system. Among them, the core control system includes the regulation of control rods and the regulation of the main pump speed, and the steam generator control system includes the regulation of the feed water flow rate. In the lead-cooled fast reactor core, the rod speed of the control rods is adjusted by simultaneously obtaining the power deviation and the coolant average temperature deviation. The speed of the main pump is adjusted by the feedback of the coolant flow rate. In the once-through steam generator, the feed water flow rate is adjusted by using the feedforward plus cascade control method to control the steam pressure. The present invention provides a control strategy and method for a lead-cooled fast reactor system, which improves the automation level of the lead-cooled fast reactor, greatly reduces the burden on the operating personnel, and enables the lead-cooled fast reactor to have better dynamic response quality and obtain ideal regulation characteristics.

The application discloses a method for purifying and diversifying products of helium-rich low-grade natural gas, and belongs to the technical field of natural gas purification. In view of the key problem that there is a lack of relatively economical natural gas helium extraction and synchronous denitrogenation technology in China, a topological structure design strategy of a cascade coupling process with complementary advantages of multiple separation membranes, an electrochemical hydrogen pump and adsorption is proposed. The advantages of the separation unit are determined by taking the helium recovery rate, the helium purity, the heat value of long-distance pipeline natural gas, the methane recovery rate and the energy consumption as multi-objective criteria, the overall design and collaborative optimization of the multi-technology coupling production of diversified products are realized, the separation energy consumption is effectively reduced, and the production of diversified products such as helium and long-distance pipeline natural gas from the helium-rich low-grade natural gas is realized at low cost and high yield.

The invention discloses a flotation reagent for copper-molybdenum-gold-silver sulfide ore and a cascade enrichment flotation method for the copper-molybdenum-gold-silver sulfide ore, and relates to the technical field of mineral flotation. A composite inhibitor is formed by compounding nitration modified humic acid and nano silicon dioxide according to the mass ratio, synchronous collection of copper, molybdenum and gold is enhanced under the action of a composite collecting agent, and the flotation efficiency of the copper-molybdenum-gold-silver sulfide ore is improved. According to the composite collecting agent, mercaptobenzothiazole and hydroximic acid are compounded, and the recovery rate of gold and silver is increased through the synergistic effect. The process comprises a mixed flotation stage and a stepped separation stage, and copper-molybdenum-gold-silver concentrate is finally obtained. The method solves the problems of difficult sulfur-noble metal separation and high medicament toxicity in the traditional process, and has the advantages of high efficiency, environmental protection and short process.

This invention discloses a highly efficient method for reducing ferric ions in zinc leaching solution, belonging to the field of hydrometallurgical technology. The zinc leaching solution and zinc sulfide concentrate are placed in a closed reactor and subjected to a pressure-enhanced reduction reaction at a temperature of 100-120℃ and a pressure of 0.2-0.3 MPa to reduce the ferric ions in the leaching solution. Simultaneously, compressed air is introduced into the reaction system to prevent the generation of hydrogen sulfide gas. The reaction time is 0.5-2.0 h. The reduced reaction system is then settled and filtered to obtain the reduced solution and reduced sulfur residue. This technical solution innovatively proposes the use of compressed air for pressure-enhanced reduction of Fe in zinc leaching solution. 3+ This achieves the suppression of H2S gas generation while avoiding the reduction of Fe. 2+ It is oxidized again to Fe by a high concentration of O2. 3+ The pressurized reduction process within a closed container significantly improves reduction efficiency while enhancing the production environment. It achieves the cascade separation and enrichment of multiple metals, closed-loop circulation of the medium, and the reduction, resource recovery, and harmless treatment of slag.

The invention discloses a method and a device for separating and refining a reaction product of preparing methyl glycolate from oxalate. The device mainly comprises a cooler, a liquid separation tank, a pre-separation tower, an MG rectifying tower, a methanol rectifying tower and an EG rectifying tower. According to the invention, a step-by-step cooling and liquid separation mode is adopted for synthesizing reaction products, circulating gas and the reaction products are separated, and compared with traditional one-time cooling and liquid separation, gradient utilization of cold public engineering can be realized, and energy consumption can be greatly saved. Meanwhile, liquid phases cooled and separated step by step respectively enter different feeding positions of the pre-separation tower, so that the separation energy consumption of the pre-separation tower can be reduced.