Volume configuration optimization method for wind-solar hydrogen production coupled pure oxygen aeration sewage treatment model

Abstract

The invention discloses a capacity configuration optimization method of a wind and light hydrogen production coupled pure oxygen aeration sewage treatment model. The method comprises the following steps: constructing a wind-solar hydrogen production coupled pure oxygen aeration sewage treatment system; a wind-solar hydrogen production coupled pure oxygen aeration sewage treatment model is constructed, and the model is used for optimizing the capacity of each subsystem, balancing the investment cost and the operation cost of each subsystem, and achieving the goal of the lowest total cost of the wind-solar hydrogen production coupled pure oxygen aeration sewage treatment system; setting constraint conditions of an objective function of the model; and solving the target function by using a solver to obtain the optimal value of each decision variable, and further obtaining the optimal capacity configuration of each component in the wind-solar hydrogen production coupled pure oxygen aeration sewage treatment system. According to the system, the resource utilization rate is increased through coupling of the sewage treatment plant and the wind and light hydrogen production system, the highest economical efficiency of the system is achieved through capacity configuration optimization, and guidance suggestions are provided for investment planning of the system.

Description

Technical Field

[0001] The present invention relates to the field of integrated energy technology, and in particular to a capacity configuration optimization method for a wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment model. Background Art

[0002] Against the backdrop of the rapid growth of global energy demand and increasingly severe environmental problems, the importance of hydrogen production from renewable energy has become increasingly prominent. Hydrogen production from renewable resources such as wind and solar energy can convert intermittent energy into high-energy-density hydrogen, achieve efficient storage and flexible deployment, enhance the stability of energy supply, and reduce dependence on fossil fuels. As a clean energy, hydrogen energy produces almost no greenhouse gases and other pollutants during its production and use, which helps to reduce carbon emissions, improve air quality, mitigate climate change, and promote the development of global environmental protection. With the advancement of hydrogen production technology and its large-scale application, the hydrogen energy industry will become a new economic growth point, promote the optimization of energy structure and innovation of the industrial chain, create a large number of jobs, and improve overall economic benefits. Hydrogen production from renewable energy has significant advantages in energy, environment and economy, and is an important way and solution to achieve global sustainable development goals.

[0003] At present, the downstream of water electrolysis hydrogen production is mostly focused on the utilization of hydrogen, such as power system energy storage, fuel cell vehicles and other fields. However, the byproduct oxygen in the water electrolysis process is less utilized, resulting in waste of resources, thereby reducing the economic efficiency of the overall hydrogen production. According to the chemical reaction formula for water electrolysis, 0.2kg of hydrogen and 0.8kg of oxygen can be produced for every 1kg of water electrolyzed. Electric hydrogen production parks focus more on the utilization of hydrogen and lack the resource utilization of oxygen. The storage cost of high-purity oxygen is high and is accompanied by certain safety hazards. If it is discharged directly, it will not only cause waste of resources, but also reduce the economic benefits of the overall process.

[0004] Traditional sewage treatment plants generally use the activated sludge method to degrade and remove organic matter in water. Activated sludge is a sludge-like substance mixed with various microorganisms. These microorganisms can decompose organic matter in wastewater and convert it into harmless waste and gas. During the treatment process, the respiration and decomposition of microorganisms require a large amount of oxygen. The specific operation method is to use a Roots blower or a centrifugal blower to directly expose air to the bottom of the aerobic tank, so that the oxygen in the air dissolves, thereby allowing the reaction to proceed smoothly.

[0005] However, the existing sewage treatment technology of exposing air to the bottom of the aerobic tank has the following problems:

[0006] First, since the oxygen content in the air is only 21%, according to the basic principle of oxygen mass transfer, the oxygen transfer resistance is large, resulting in low efficiency of air aeration. Due to the low efficiency of air aeration, high-energy consumption aeration equipment is required to meet the requirements of sewage treatment, resulting in the aeration energy consumption of the sewage treatment plant accounting for 60% of the total daily sewage operation energy consumption;

[0007] Second, in order to provide enough oxygen to meet the needs of microorganisms, the volume of the aeration tank needs to be increased accordingly, thus occupying a large amount of land area. Summary of the invention

[0008] In view of the shortcomings of the prior art, the present invention proposes a capacity configuration optimization method for a wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment model, which couples the by-product oxygen produced by the wind-solar hydrogen production system with the sewage treatment process, optimizes the operation plan of the water electrolysis hydrogen production, oxygen production equipment and sewage treatment system, and makes full use of the by-product oxygen of new energy hydrogen production, which is conducive to optimizing the consumption of new energy and improving the utilization efficiency of new energy.

[0009] To achieve the above object, the present invention designs a capacity configuration optimization method for a wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment model, which is particularly characterized in that it includes the following steps:

[0010] S1) Building a wind-solar hydrogen production coupled pure oxygen aeration sewage treatment system, the system includes a new energy generation subsystem, a lithium-ion battery energy storage subsystem, an electrolysis hydrogen production subsystem, an air compressor subsystem, and an aerator subsystem respectively connected to a DC bus; the oxygen generated by the electrolysis hydrogen production subsystem is transmitted to the air compressor subsystem, and the generated hydrogen is sold; the oxygen output by the air compressor subsystem is transmitted to the oxygen storage tank subsystem, the oxygen output by the oxygen storage tank subsystem is transmitted to the aerator subsystem, and the oxygen output by the aerator subsystem is transmitted to the biological reaction tank subsystem, and the sewage in the biological reaction tank subsystem comes from the water storage tank subsystem;

[0011] S2) constructing a wind-solar hydrogen production coupled pure oxygen aeration sewage treatment model, which is used to optimize the capacity of each subsystem, weigh the investment cost and operation cost of each subsystem, and achieve the goal of minimizing the total cost of the wind-solar hydrogen production coupled pure oxygen aeration sewage treatment system; the objective function of the model is as follows:

[0012]

[0013] In the formula,

[0014] J is the total cost of the wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment system,

[0015] min is the minimum value,

[0016] ∑ is the sum,

[0017] Cost AC,i is the unit investment cost of component i, i=1,2…n,

[0018] Cap i is the capacity of component i,

[0019] Cost OP,j is the operating cost of component j, j = 1, 2…m,

[0020] E t,j is the energy flow of component j at time t,

[0021] c sell is the selling price of hydrogen,

[0022] is the amount of hydrogen produced at time t;

[0023] S3) setting constraints of the objective function of the model, wherein the constraints include power balance constraints, lithium-ion battery energy storage constraints, electrolysis hydrogen production operation constraints, air compressor model constraints, oxygen storage tank energy storage constraints, aerator model constraints, bioreactor operation constraints, and reservoir constraints;

[0024] S4) Under the constraints of step S3), the objective function of step S2) is solved using a solver to obtain the optimal value of each decision variable, and then the optimal capacity configuration of each component in the wind-solar hydrogen production coupled pure oxygen aeration sewage treatment system is obtained.

[0025] Further, in S3), the new energy power generation subsystem includes a photovoltaic power generation subsystem and a wind power generation subsystem;

[0026] The power balance constraint conditions are as follows:

[0027] P s,t +P w,t +P lib_out,t =P e,t +P w1,t +P w2,t +P lib_in,t ,t=1,2,3...Twhere,

[0028] P s,t is the photovoltaic power generation power at time t,

[0029] P w,t is the wind turbine power at time t,

[0030] P lib_out,t is the discharge power of the lithium-ion battery at time t,

[0031] P e,tis the hydrogen production power of the electrolytic hydrogen production device at time t,

[0032] P w1,t is the operating power of the air compressor at time t,

[0033] P w2,t is the operating power of the aerator at time t,

[0034] P lib_in,t is the charging power of the lithium-ion battery at time t.

[0035] Furthermore, in S3), the lithium-ion battery energy storage constraint conditions are as follows:

[0036]

[0037] In the formula,

[0038] P lib_out,t is the discharge power of the lithium-ion battery at time t,

[0039] P lib_out,min is the minimum discharge power of lithium-ion batteries,

[0040] P lib_out,max is the maximum discharge power of lithium-ion battery,

[0041] P lib_in,t is the charging power of the lithium-ion battery at time t,

[0042] P lib_in,min is the minimum charging power of lithium-ion batteries,

[0043] P lib_in,max is the maximum charging power of lithium-ion batteries,

[0044] is the charging efficiency of lithium-ion batteries,

[0045] is the discharge efficiency of lithium-ion batteries,

[0046] Cap lib,t-1 is the battery capacity of the lithium-ion battery at time t-1,

[0047] Cap lib,t is the battery capacity of the lithium-ion battery at time t,

[0048] Cap lib,max is the maximum battery capacity of the lithium-ion battery,

[0049] Cap lib,min is the minimum battery capacity of lithium-ion batteries,

[0050] Cap lib,1is the power of the lithium-ion battery at time t=1 in the scheduling cycle, that is, the initial value of the power of the lithium-ion battery,

[0051] Cap lib,T It is the power at time t=T, that is, the power of the lithium-ion battery at the end of an optimization cycle, and T is a scheduling cycle.

[0052] Furthermore, in S3), the operating constraints of the electrolysis hydrogen production are as follows:

[0053]

[0054] P e,min ≤P e,t ≤P e,nom

[0055]

[0056] In the formula,

[0057] is the hydrogen production rate of the electrolytic hydrogen production device at time t,

[0058] is the power required by the electrolytic hydrogen production device to produce 1 kg of hydrogen at time t,

[0059] P e,nom The rated hydrogen production power of the electrolytic hydrogen production device is:

[0060] P e,t is the operating power of the electrolytic hydrogen production device at time t,

[0061] P e_min is the minimum hydrogen production power of the electrolytic hydrogen production device,

[0062] is the oxygen production rate of the hydrogen electrolysis device at time t.

[0063] Furthermore, in S3), the air compressor model constraint conditions are as follows:

[0064]

[0065] In the formula,

[0066] P w1,t is the operating power of the air compressor at time t,

[0067] κ is the oxygen adiabatic coefficient,

[0068] R is the ideal gas constant

[0069] T c1in,t is the air inlet temperature of the air compressor at time t,

[0070] η c1 is the aeration efficiency of the air compressor when it is running,

[0071] p 1out,t is the gas pressure at the outlet of the air compressor at time t, in kPa,

[0072] p 1in,t is the gas pressure at the air compressor inlet at time t, in kPa,

[0073] Gs 1in,t is the air intake flow rate of the air compressor at time t, Nm 3 / h,

[0074] is the oxygen production rate of the hydrogen electrolysis device at time t.

[0075] Furthermore, in S3), the energy storage constraint conditions of the oxygen storage tank are as follows:

[0076]

[0077] Gs in,t =Gs 1in,t

[0078] Gs out,t =Gs 2in,t

[0079] In the formula,

[0080] p ws,t is the pressure of the oxygen storage tank at time t,

[0081] R is the ideal gas constant,

[0082] T is the temperature of oxygen in the oxygen storage tank,

[0083] ρ is the oxygen density in the oxygen storage tank,

[0084] V is the volume of the oxygen storage tank,

[0085] M is the molar mass of oxygen in the oxygen storage tank,

[0086] Gs in,t-1 is the inlet gas flow rate of the oxygen storage tank,

[0087] Gs out,t-1 is the outlet gas flow rate of the oxygen storage tank,

[0088] p ws,t-1 is the pressure of the oxygen storage tank at time t-1,

[0089] p ws,min is the minimum pressure of the oxygen tank,

[0090] p ws,max is the maximum pressure of the oxygen storage tank,

[0091] p ws,1 is the initial pressure of the oxygen tank,

[0092] p ws,T is the pressure of the oxygen tank at the end of the optimization cycle,

[0093] Gs in,t is the inlet gas flow rate of the oxygen storage tank at time t,

[0094] Gs 1in,t is the inlet gas flow rate of the compressor at time t,

[0095] Gs out,t is the outlet gas flow rate of the oxygen storage tank at time t,

[0096] Gs 2in,t is the inlet gas flow rate of the aerator at time t.

[0097] Furthermore, in S3), the aerator model constraint conditions are as follows:

[0098]

[0099] In the formula,

[0100] P w2,t is the operating power of the aerator at time t,

[0101] κ is the oxygen adiabatic coefficient,

[0102] R is the ideal gas constant,

[0103] T c2in,t is the air inlet temperature of the aerator at time t,

[0104] η c2 is the aeration efficiency of the aerator during operation,

[0105] p 2out,t is the gas pressure at the outlet of the aerator at time t, in kPa,

[0106] p 2in,t is the gas pressure at the aerator's air inlet at time t, in kPa,

[0107] Gs 2in,t is the air intake flow rate of the aerator at time t, Nm 3 / h.

[0108] Furthermore, in S3), the operating constraints of the bioreactor are as follows: 0,t =0.001aQ out,t (So,t -S e )-cΔX V +b(0.001Q out,t (N k,t -N ke )

[0109] -0.12ΔX V )-0.62b(0.001Q out,t (N t,t -N ke -N oe )-0.12ΔX V )

[0110]

[0111]

[0112] In the formula,

[0113] R 0,t is the actual oxygen demand of sewage, unit is kgO2 / d,

[0114] a is the oxygen equivalent of carbon. When carbon-containing substances are measured in BOD5,

[0115] Q out,t is the outflow rate of the reservoir at time t, in m 3 / d,

[0116] S o,t is the influent BOD5 concentration of the biological reactor, in mg / L.

[0117] S e The BOD5 concentration of the effluent from the biological reactor is in mg / L.

[0118] c is the oxygen equivalent of the bacterial cell

[0119] ΔX V is the amount of microorganisms discharged from the bioreactor, in kg / d.

[0120] b is the oxygen required to oxidize each kilogram of ammonia nitrogen, unit is kgO2 / kg N,

[0121] N k,t is the total Kjeldahl nitrogen concentration of the influent of the bioreactor at time t, in mg / L.

[0122] N ke is the total Kjeldahl nitrogen concentration in the effluent from the biological reactor, in mg / L.

[0123] N t,t is the total nitrogen concentration of the influent of the bioreactor at time t, in mg / L.

[0124] N oe is the nitrate nitrogen concentration of the effluent from the biological reactor, in mg / L.

[0125] 0.12ΔX V The nitrogen content of microorganisms discharged from the bioreactor is in kg / d.

[0126] R t is the standard oxygen demand of sewage at time t, in kgO2 / d,

[0127] C S is the saturated dissolved oxygen in clean water under standard conditions,

[0128] α is K in the mixed solution La Value and K in clean water La The ratio of values,

[0129] β is the ratio of the saturated dissolved oxygen value of the mixed solution to the saturated dissolved oxygen value of the clean water.

[0130] C stn,t The average dissolved oxygen in the clean water from the underwater depth to the pool surface of the aeration device at time t, in mg / L.

[0131] C o is the residual dissolved oxygen concentration of the mixed solution,

[0132] T is the temperature of the mixed liquid,

[0133] Gs out,t is the oxygen flow rate at the aerator outlet at time t,

[0134] is the oxygen density, in g / m 3 ,

[0135] E A is the oxygen utilization rate of the aerator (%).

[0136] Furthermore, in S3), the water reservoir constraint conditions are as follows:

[0137]

[0138] In the formula,

[0139] Q out,t is the outflow rate of sewage from the reservoir at time t,

[0140] Q out,min is the minimum outflow rate of sewage from the reservoir,

[0141] Q out,max is the maximum outflow rate of sewage from the reservoir,

[0142] Qin,t is the inflow flow rate of sewage into the reservoir at time t,

[0143] Q in,min is the minimum inflow flow rate of sewage into the reservoir,

[0144] Q in,max is the maximum inflow flow of sewage into the reservoir,

[0145] Cap ct,t-1 is the capacity of the reservoir at time t-1,

[0146] Cap ct,t is the capacity of the reservoir at time t,

[0147] Cap ct,min The minimum volume of sewage that the reservoir can hold.

[0148] Cap ct,max The maximum volume of sewage that the reservoir can hold;

[0149] Cap ct,1 is the initial sewage volume of the reservoir;

[0150] Cap ct,T Optimize the sewage volume at the end of the cycle for the water storage tank.

[0151] Furthermore, in S4), the solver is Gurobi or CPLEX.

[0152] The advantages of the present invention are:

[0153] 1. The present invention builds a wind-solar hydrogen production coupled pure oxygen aeration sewage treatment system, which couples the sewage treatment plant with the renewable energy hydrogen production system, uses renewable energy to provide energy for the water electrolysis hydrogen production equipment, and then uses the byproduct oxygen produced by the water electrolysis hydrogen production equipment to provide pure oxygen for the aerobic biological reaction of the sewage treatment plant, thereby reducing the power consumption of the sewage treatment aerator and greatly reducing the operating cost of the sewage treatment plant; at the same time, the hydrogen produced by the electrolysis of water is sold to the sewage treatment plant, increasing the absorption capacity of renewable energy and improving the economy of renewable energy hydrogen production. By coupling the sewage treatment plant with the wind-solar hydrogen production system, the resource utilization rate is enhanced and the waste of resources is avoided;

[0154] 2. The present invention constructs a wind-solar hydrogen production coupled pure oxygen aeration sewage treatment model and a capacity configuration optimization method. The model aims to minimize the total system cost (including investment and operating costs) and provides optimal capacity configuration for each subsystem in the wind-solar hydrogen production-pure oxygen aeration sewage treatment coupling system (including photovoltaic power generation system, wind power generation system, lithium-ion battery energy storage system, electrolysis hydrogen production system, oxygen tank energy storage system, air compressor system, aerator system, and reservoir system). The obtained capacity configuration optimization scheme achieves the highest economic efficiency and provides guidance for investment planning of the system;

[0155] The capacity configuration optimization method of the wind-solar hydrogen production coupled pure oxygen aeration sewage treatment model of the present invention not only enhances resource utilization by coupling the sewage treatment plant with the wind-solar hydrogen production system, but also achieves the highest system economy through capacity configuration optimization, and provides guidance for investment planning of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0156] Figure 1 It is a flow chart of the capacity configuration optimization method of the wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment model of the present invention;

[0157] Figure 2 It is a structural block diagram of the wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment system in the present invention;

[0158] Figure 3 is a renewable energy power variation curve in the embodiment;

[0159] Figure 4 The operating power curve of the electrolytic hydrogen production device and the aerator operating power curve in the embodiment;

[0160] Figure 5 It is the sewage flow curve entering the water storage tank in the embodiment. DETAILED DESCRIPTION

[0161] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0162] like Figure 1 As shown, the capacity configuration optimization method of a wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment model of the present invention comprises the following steps:

[0163] S1) Build a wind-solar hydrogen production coupled pure oxygen aeration sewage treatment system, the system includes a new energy power generation subsystem, a lithium-ion battery energy storage subsystem, an electrolysis hydrogen production subsystem, an air compressor subsystem, and an aerator subsystem respectively connected to a DC bus; the oxygen generated by the electrolysis hydrogen production subsystem is transmitted to the air compressor subsystem, and the generated hydrogen is sold; the oxygen output by the air compressor subsystem is transmitted to the oxygen storage tank subsystem, the oxygen output by the oxygen storage tank subsystem is transmitted to the aerator subsystem, and the oxygen output by the aerator subsystem is transmitted to the biological reaction tank subsystem, and the sewage in the biological reaction tank subsystem comes from the water storage tank subsystem.

[0164] like Figure 2 The figure shows the structural block diagram of the wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment system in the invention. The new energy power generation subsystem includes a photovoltaic power generation subsystem and a wind power generation subsystem.

[0165] In this embodiment, the photovoltaic panel in the photovoltaic power generation subsystem is 300W, and the wind turbine in the wind power generation subsystem generates 20kW of electricity.

[0166] S2) constructing a wind-solar hydrogen production coupled pure oxygen aeration sewage treatment model, which is used to optimize the capacity of each subsystem, weigh the investment cost and operation cost of each subsystem, and achieve the goal of minimizing the total cost of the wind-solar hydrogen production coupled pure oxygen aeration sewage treatment system; the objective function of the model is as follows:

[0167]

[0168] In the formula,

[0169] J is the total cost of the wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment system,

[0170] min is the minimum value,

[0171] ∑ is the sum,

[0172] Cost AC,i is the unit investment cost of component i, i = 1, 2…n, i includes wind power generation, photovoltaic power generation, lithium-ion batteries, oxygen storage tanks, and electric hydrogen production equipment,

[0173] Cap i is the capacity of component i,

[0174] Cost OP,j is the operating cost of component j, j = 1, 2…m, j includes lithium-ion batteries, oxygen storage tanks,

[0175] E t,j is the energy flow of component j at time t,

[0176] c sell is the selling price of hydrogen,

[0177] m H2,t is the amount of hydrogen produced at time t.

[0178] The present invention builds a wind-solar hydrogen production coupled pure oxygen aeration sewage treatment system, which couples the sewage treatment plant with the renewable energy hydrogen production system, utilizes renewable energy to provide energy for the water electrolysis hydrogen production equipment, and then utilizes the byproduct oxygen produced by the water electrolysis hydrogen production equipment to provide pure oxygen for the aerobic biological reaction of the sewage treatment plant, thereby reducing the power consumption of the sewage treatment aerator and greatly reducing the operating cost of the sewage treatment plant; at the same time, the hydrogen produced by the electrolysis of water is sold to the sewage treatment plant, thereby increasing the absorption capacity of renewable energy and improving the economy of renewable energy hydrogen production. Through the coupling of the sewage treatment plant with the wind-solar hydrogen production system, the resource utilization rate is enhanced and the waste of resources is avoided.

[0179] The unit prices of the components in this embodiment are shown in Table 1.

[0180] Table 1 Unit price of each component

[0181] Unit price of each component Unit Price Rated power of hydrogen production 16.54 yuan / W Single wind turbine installed capacity 9.4 yuan / W Photovoltaic panels 6.3 yuan / Wp Lithium-ion battery 4.72 yuan / Wh Oxygen storage tank (30Mpa) 100 yuan / L <![CDATA[Hydrogen selling price c sell > 40 yuan / kg

[0182] S3) setting constraints of the objective function of the model, wherein the constraints include power balance constraints, lithium-ion battery energy storage constraints, electrolysis hydrogen production operation constraints, air compressor model constraints, oxygen storage tank energy storage constraints, aerator model constraints, bioreactor operation constraints, and reservoir constraints.

[0183] The present invention constructs a wind-solar hydrogen production coupled pure oxygen aeration sewage treatment model and a capacity configuration optimization method. The model aims to minimize the total system cost (including investment and operating costs) and provides optimal capacity configuration for each subsystem in the wind-solar hydrogen production-pure oxygen aeration sewage treatment coupling system (including photovoltaic power generation system, wind power generation system, lithium-ion battery energy storage system, electrolysis hydrogen production system, oxygen tank energy storage system, air compressor system, aerator system, and reservoir system). The obtained capacity configuration optimization scheme achieves the highest economy and provides guiding opinions on investment planning of the system.

[0184] Specifically, when the new energy generation subsystem includes a photovoltaic generation subsystem and a wind power generation subsystem, the power balance constraint condition is as follows:

[0185] P s,t +P w,t +P lib_out,t =P e,t +P w1,t +P w2,t +P lib_in,t ,t=1,2,3...Twhere,

[0186] Ps,t is the photovoltaic power generation power at time t,

[0187] P w,t is the wind turbine power at time t,

[0188] P lib_out,t is the discharge power of the lithium-ion battery at time t,

[0189] P e,t is the hydrogen production power of the electrolytic hydrogen production device at time t,

[0190] P w1,t is the operating power of the air compressor at time t,

[0191] P w2,t is the operating power of the aerator at time t,

[0192] P lib_in,t is the charging power of the lithium-ion battery at time t.

[0193] In this embodiment, the variation curves of wind power and photovoltaic power generation are as follows: Figure 3 described.

[0194] Specifically, the lithium-ion battery energy storage constraints are as follows:

[0195]

[0196] In the formula,

[0197] P lib_out,t is the discharge power of the lithium-ion battery at time t,

[0198] P lib_out,min is the minimum discharge power of lithium-ion batteries,

[0199] P lib_out,max is the maximum discharge power of lithium-ion battery,

[0200] P lib_in,t is the charging power of the lithium-ion battery at time t,

[0201] P lib_in,min is the minimum charging power of lithium-ion batteries,

[0202] P lib_in,max is the maximum charging power of lithium-ion batteries,

[0203] is the charging efficiency of lithium-ion batteries,

[0204] is the discharge efficiency of lithium-ion batteries,

[0205] Cap lib,t-1is the battery capacity of the lithium-ion battery at time t-1,

[0206] Cap lib,t is the battery capacity of the lithium-ion battery at time t,

[0207] Cap lib,max is the maximum battery capacity of the lithium-ion battery,

[0208] Cap lib,min is the minimum battery capacity of lithium-ion batteries,

[0209] Cap lib,1 is the power of the lithium-ion battery at time t=1 in the scheduling cycle, that is, the initial value of the power of the lithium-ion battery,

[0210] Cap lib,T It is the power at time t=T, that is, the power of the lithium-ion battery at the end of an optimization cycle, and T is a scheduling cycle.

[0211] Specifically, the operating constraints of the electrolysis hydrogen production are as follows:

[0212]

[0213] P e,min ≤P e,t ≤P e,nom

[0214]

[0215] In the formula,

[0216] is the hydrogen production rate of the electrolytic hydrogen production device at time t,

[0217] is the power required by the electrolytic hydrogen production device to produce 1 kg of hydrogen at time t,

[0218] P e,nom The rated hydrogen production power of the electrolytic hydrogen production device is:

[0219] P e,t is the operating power of the electrolytic hydrogen production device at time t,

[0220] P e_min is the minimum hydrogen production power of the electrolytic hydrogen production device,

[0221] is the oxygen production rate of the hydrogen electrolysis device at time t.

[0222] Specifically, the constraints of the air compressor model are as follows:

[0223]

[0224] In the formula,

[0225] P w1,t is the operating power of the air compressor at time t,

[0226] κ is the oxygen adiabatic coefficient,

[0227] R is the ideal gas constant, which is 8.314 J / (mol·K).

[0228] T c1in,t is the air inlet temperature of the air compressor at time t, η c1 is the aeration efficiency of the air compressor when it is running, p 1out,t is the gas pressure at the outlet of the air compressor at time t, in kPa, p 1in,t is the air pressure at the air compressor inlet at time t, in kPa, Gs 1in,t is the air intake flow rate of the air compressor at time t, Nm 3 / h, is the oxygen production rate of the hydrogen electrolysis device at time t.

[0229] Specifically, the energy storage constraints of the oxygen storage tank are as follows:

[0230]

[0231] Gs in,t =Gs 1in,t

[0232] Gs out,t =Gs 2in,t

[0233] In the formula,

[0234] p ws,t is the pressure of the oxygen storage tank at time t,

[0235] R is the ideal gas constant, which is 8.314 J / (mol·K).

[0236] T is the temperature of oxygen in the oxygen storage tank,

[0237] ρ is the oxygen density in the oxygen storage tank,

[0238] V is the volume of the oxygen storage tank,

[0239] M is the molar mass of oxygen in the oxygen storage tank,

[0240] Gs in,t-1 is the inlet gas flow rate of the oxygen storage tank,

[0241] Gs out,t-1 is the outlet gas flow rate of the oxygen storage tank,

[0242] p ws,t-1 is the pressure of the oxygen storage tank at time t-1,

[0243] p ws,min is the minimum pressure of the oxygen tank,

[0244] p ws,max is the maximum pressure of the oxygen storage tank,

[0245] p ws,1 is the initial pressure of the oxygen tank,

[0246] p ws,T is the pressure of the oxygen tank at the end of the optimization cycle,

[0247] Gs in,t is the inlet gas flow rate of the oxygen storage tank at time t,

[0248] Gs 1in,t is the inlet gas flow rate of the compressor at time t, that is, the inlet flow rate of the air compressor and the aerator is assumed to be the same.

[0249] Gs out,t is the outlet gas flow rate of the oxygen storage tank at time t,

[0250] Gs 2in,t It is the inlet gas flow of the aerator at time t, that is, the air intake flow of the air compressor and the aerator is assumed to be the same.

[0251] Specifically, the constraints of the aerator model are as follows:

[0252]

[0253] In the formula,

[0254] P w2,t is the operating power of the aerator at time t,

[0255] κ is the oxygen adiabatic coefficient,

[0256] R is the ideal gas constant, which is 8.314 J / (mol·K).

[0257] T c2in,t is the air inlet temperature of the aerator at time t,

[0258] η c2 is the aeration efficiency of the aerator during operation,

[0259] p 2out,t is the gas pressure at the outlet of the aerator at time t, in kPa,

[0260] p 2in,t is the gas pressure at the aerator's air inlet at time t, in kPa,

[0261] Gs 2in,t is the air intake flow rate of the aerator at time t, Nm 3 / h.

[0262] In this embodiment, the operating power of the electrolytic hydrogen production device and the operating power of the aerator are as follows: Figure 4 shown.

[0263] Specifically, the operating constraints of the bioreactor are as follows:

[0264] R 0,t =0.001aQ out,t (S o,t -S e )-cΔX V +b(0.001Q out,t (N k,t -N ke )

[0265] -0.12ΔX V )-0.62b(0.001Q out,t (N t,t -N ke -N oe )-0.12ΔX V )

[0266]

[0267] In the formula,

[0268] R 0,t is the actual oxygen demand of sewage, unit is kgO2 / d,

[0269] a is the oxygen equivalent of carbon. When carbon-containing substances are measured as BOD5, the value is 1.47.

[0270] Q out,t is the outflow rate of the reservoir at time t, in m 3 / d,

[0271] S o,t is the influent BOD5 concentration of the biological reactor, in mg / L.

[0272] S e The BOD5 concentration of the effluent from the biological reactor is in mg / L.

[0273] c is the oxygen equivalent of bacterial cells, which is 1.42.

[0274] ΔX V is the amount of microorganisms discharged from the bioreactor, in kg / d.

[0275] b is the oxygen demand for oxidizing one kilogram of ammonia nitrogen, in kgO2 / kg N, with a value of 4.57.

[0276] N k,t is the total Kjeldahl nitrogen concentration of the influent of the bioreactor at time t, in mg / L.

[0277] N ke is the total Kjeldahl nitrogen concentration in the effluent from the biological reactor, in mg / L.

[0278] N t,t is the total nitrogen concentration of the influent of the bioreactor at time t, in mg / L.

[0279] N oe is the nitrate nitrogen concentration of the effluent from the biological reactor, in mg / L.

[0280] 0.12ΔX V The nitrogen content of microorganisms discharged from the bioreactor is in kg / d.

[0281] R t is the standard oxygen demand of sewage at time t, in kgO2 / d,

[0282] C S is the saturated dissolved oxygen in clean water under standard conditions, with a value of 9.17 mg / L.

[0283] α is K in the mixed solution La Value and K in clean water La The ratio of the values ​​is generally 0.8 to 0.85.

[0284] β is the ratio of the saturated dissolved oxygen value of the mixed solution to the saturated dissolved oxygen value of the clean water, which is generally 0.9 to 0.97.

[0285] C stn,t The average dissolved oxygen in the clean water from the underwater depth to the pool surface of the aeration device at time t, in mg / L.

[0286] C o is the residual dissolved oxygen concentration of the mixed solution, which is 2 mg / L.

[0287] T is the temperature of the mixed liquid, which is generally 5 to 30°C.

[0288] Gs out,t is the oxygen flow rate at the aerator outlet at time t,

[0289] is the oxygen density, in g / m 3 ,

[0290] E A is the oxygen utilization rate of the aerator (%).

[0291] The discharge parameters of the biological reaction tank in this embodiment are shown in Table 2.

[0292] Table 2 Wastewater Discharge Standards

[0293] Discharge parameters of biological reactors Value <![CDATA[Microbial biomass ΔX discharged from the biological reaction tank V > 173.79kg / d <![CDATA[Total Kjeldahl nitrogen concentration N in the effluent of the biological reaction tank ke > 8.7mg / L <![CDATA[The concentration N of nitrate nitrogen in the effluent of the biological reaction tank oe > 3.03mg / L <![CDATA[Effluent BOD5 concentration Se of biological reaction tank]]> 20mg / L

[0294] Specifically, the reservoir constraints are as follows:

[0295]

[0296] In the formula,

[0297] Q out,t is the outflow rate of sewage from the reservoir at time t,

[0298] Q out,min is the minimum outflow rate of sewage from the reservoir,

[0299] Q out,max is the maximum outflow rate of sewage from the reservoir,

[0300] Q in,t is the inflow flow rate of sewage into the reservoir at time t,

[0301] Q in,min is the minimum inflow flow rate of sewage into the reservoir,

[0302] Q in,max is the maximum inflow flow of sewage into the reservoir,

[0303] Cap ct,t-1 is the capacity of the reservoir at time t-1,

[0304] Cap ct,t is the capacity of the reservoir at time t,

[0305] Cap ct,min The minimum volume of sewage that the reservoir can hold.

[0306] Cap ct,max The maximum volume of sewage that the reservoir can hold;

[0307] Cap ct,1 is the initial sewage volume of the reservoir;

[0308] Cap ct,T Optimize the sewage volume at the end of the cycle for the water storage tank.

[0309] In this embodiment, the sewage flow curve entering the reservoir is as follows: Figure 5 shown.

[0310] S4) Under the constraints of step S3), the objective function of step S2) is solved using a solver to obtain the optimal value of each decision variable, and then the optimal capacity configuration of each component in the wind-solar hydrogen production coupled pure oxygen aeration sewage treatment system is obtained.

[0311] Specifically, the solver is Gurobi or CPLEX.

[0312] The capacity configuration optimization method of the wind-solar hydrogen production coupled pure oxygen aeration sewage treatment model of the present invention not only enhances resource utilization by coupling the sewage treatment plant with the wind-solar hydrogen production system, but also achieves the highest system economy through capacity configuration optimization, and provides guidance for investment planning of the system.

[0313] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A capacity configuration optimization method for a wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment model, characterized in that: The steps include: S1) Building a wind-solar hydrogen production coupled pure oxygen aeration sewage treatment system, the system includes a new energy generation subsystem, a lithium-ion battery energy storage subsystem, an electrolysis hydrogen production subsystem, an air compressor subsystem, and an aerator subsystem respectively connected to a DC bus; the oxygen generated by the electrolysis hydrogen production subsystem is transmitted to the air compressor subsystem, and the generated hydrogen is sold; the oxygen output by the air compressor subsystem is transmitted to the oxygen storage tank subsystem, the oxygen output by the oxygen storage tank subsystem is transmitted to the aerator subsystem, and the oxygen output by the aerator subsystem is transmitted to the biological reaction tank subsystem, and the sewage in the biological reaction tank subsystem comes from the water storage tank subsystem; S2) constructing a wind-solar hydrogen production coupled pure oxygen aeration sewage treatment model, which is used to optimize the capacity of each subsystem, weigh the investment cost and operation cost of each subsystem, and achieve the goal of minimizing the total cost of the wind-solar hydrogen production coupled pure oxygen aeration sewage treatment system; the objective function of the model is as follows: In the formula, J is the total cost of the wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment system, min is the minimum value, ∑ is the sum, Cost AC,i is the unit investment cost of component i, i=1,2…n, Cap i is the capacity of component i, Cost OP,j is the operating cost of component j, j = 1, 2…m, E t,j is the energy flow of component j at time t, c sell is the selling price of hydrogen, is the amount of hydrogen produced at time t; S3) setting constraints of the objective function of the model, wherein the constraints include power balance constraints, lithium-ion battery energy storage constraints, electrolysis hydrogen production operation constraints, air compressor model constraints, oxygen storage tank energy storage constraints, aerator model constraints, bioreactor operation constraints, and reservoir constraints; S4) Under the constraints of step S3), the objective function of step S2) is solved using a solver to obtain the optimal value of each decision variable, and then the optimal capacity configuration of each component in the wind-solar hydrogen production coupled pure oxygen aeration sewage treatment system is obtained.

2. The capacity configuration optimization method of the wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment model according to claim 1 is characterized by: S3), the new energy generation subsystem includes a photovoltaic generation subsystem and a wind power generation subsystem; The power balance constraint conditions are as follows: P s,t +P w,t +P lib_out,t =P e,t +P w1,t +P w2,t +P lib_in,t ,t=1,2,3...Twhere, P s,t is the photovoltaic power generation power at time t, P w,t is the wind turbine power at time t, P lib_out,t is the discharge power of the lithium-ion battery at time t, P e,t is the hydrogen production power of the electrolytic hydrogen production device at time t, P w1,t is the operating power of the air compressor at time t, P w2,t is the operating power of the aerator at time t, P lib_in,t is the charging power of the lithium-ion battery at time t.

3. The capacity configuration optimization method of the wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment model according to claim 2 is characterized by: S3), the lithium-ion battery energy storage constraints are as follows In the formula, P lib_out,t is the discharge power of the lithium-ion battery at time t, P lib_out,min is the minimum discharge power of lithium-ion batteries, P lib_out,max is the maximum discharge power of lithium-ion battery, P lib_in,t is the charging power of the lithium-ion battery at time t, P lib_in,min is the minimum charging power of lithium-ion batteries, P lib_in,max is the maximum charging power of lithium-ion batteries, is the charging efficiency of lithium-ion batteries, is the discharge efficiency of lithium-ion batteries, Cap lib,t-1 is the battery capacity of the lithium-ion battery at time t-1, Cap lib,t is the battery capacity of the lithium-ion battery at time t, Cap lib,max is the maximum battery capacity of the lithium-ion battery, Cap lib,min is the minimum battery capacity of lithium-ion batteries, Cap lib,1 is the power of the lithium-ion battery at time t=1 in the scheduling cycle, that is, the initial value of the power of the lithium-ion battery, Cap lib,T It is the power at time t=T, that is, the power of the lithium-ion battery at the end of an optimization cycle, and T is a scheduling cycle.

4. The capacity configuration optimization method of the wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment model according to claim 3 is characterized by: S3), the operating constraints of the electrolysis hydrogen production are as follows P e,min ≤P e,t ≤P e,nom In the formula, is the hydrogen production rate of the electrolytic hydrogen production device at time t, is the power required by the electrolytic hydrogen production device to produce 1 kg of hydrogen at time t, P e,nom The rated hydrogen production power of the electrolytic hydrogen production device is: P e,t is the operating power of the electrolytic hydrogen production device at time t, P e_min is the minimum hydrogen production power of the electrolytic hydrogen production device, is the oxygen production rate of the hydrogen electrolysis device at time t.

5. The capacity configuration optimization method of the wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment model according to claim 4 is characterized by: S3), the air compressor model constraints are as follows In the formula, P w1,t is the operating power of the air compressor at time t, κ is the oxygen adiabatic coefficient, R is the ideal gas constant, T c1in,t is the air inlet temperature of the air compressor at time t, η c1 is the aeration efficiency of the air compressor when it is running, p 1out,t is the gas pressure at the outlet of the air compressor at time t, in kPa, p 1in,t is the gas pressure at the air compressor inlet at time t, in kPa, Gs 1in,t is the air intake flow rate of the air compressor at time t, Nm 3 / h, is the oxygen production rate of the hydrogen electrolysis device at time t.

6. The capacity configuration optimization method of the wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment model according to claim 5 is characterized by: In S3), the energy storage constraint conditions of the oxygen storage tank are as follows: Gs in,t =Gs 1in,t Gs out,t =Gs 2in,t In the formula, p ws,t is the pressure of the oxygen tank at time t, R is the ideal gas constant, T is the temperature of oxygen in the oxygen storage tank, ρ is the oxygen density in the oxygen storage tank, V is the volume of the oxygen storage tank, M is the molar mass of oxygen in the oxygen storage tank, Gs in,t-1 is the inlet gas flow rate of the oxygen storage tank, Gs out,t-1 is the outlet gas flow rate of the oxygen storage tank, p ws,t-1 is the pressure of the oxygen storage tank at time t-1, p ws,min is the minimum pressure of the oxygen tank, p ws,max is the maximum pressure of the oxygen storage tank, p ws,1 is the initial pressure of the oxygen tank, p ws,T is the pressure of the oxygen tank at the end of the optimization cycle, Gs in,t is the inlet gas flow rate of the oxygen storage tank at time t, Gs 1in,t is the inlet gas flow rate of the compressor at time t, Gs out,t is the outlet gas flow rate of the oxygen storage tank at time t, Gs 2in,t is the inlet gas flow rate of the aerator at time t.

7. The capacity configuration optimization method of the wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment model according to claim 6 is characterized by: In S3), the aerator model constraints are as follows: In the formula, P w2,t is the operating power of the aerator at time t, κ is the oxygen adiabatic coefficient, R is the ideal gas constant, T c2in,t is the air inlet temperature of the aerator at time t, η c2 is the aeration efficiency of the aerator during operation, p 2out,t is the gas pressure at the outlet of the aerator at time t, in kPa, p 2in,t is the gas pressure at the aerator's air inlet at time t, in kPa, Gs 2in,t is the air intake flow rate of the aerator at time t, Nm 3 / h.

8. The capacity configuration optimization method of the wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment model according to claim 7 is characterized by: S3), the operating constraints of the bioreactor are as follows: R 0,t =0.001aQ out,t (S o,t -S e )-cΔX V +b(0.001Q out,t (N k,t -N ke )-0.12ΔX V )-0.62b(0.001Q out,t (N t,t -N ke -N oe )-0.12ΔX V ) In the formula, R 0,t is the actual oxygen demand of sewage, unit is kgO2 / d, a is the oxygen equivalent of carbon. When carbon-containing substances are measured in BOD5, Q out,t is the outflow rate of the reservoir at time t, in m 3 / d, S o,t is the influent BOD5 concentration of the biological reactor, in mg / L. S e The BOD5 concentration of the effluent from the biological reactor is in mg / L. c is the oxygen equivalent of the bacterial cell, ΔX V is the amount of microorganisms discharged from the bioreactor, in kg / d. b is the oxygen required to oxidize each kilogram of ammonia nitrogen, unit is kgO2 / kg N, N k,t is the total Kjeldahl nitrogen concentration of the influent of the bioreactor at time t, in mg / L. N ke is the total Kjeldahl nitrogen concentration in the effluent from the biological reactor, in mg / L. N t,t is the total nitrogen concentration of the influent of the bioreactor at time t, in mg / L. N oe is the nitrate nitrogen concentration of the effluent from the biological reactor, in mg / L. 0.12ΔX V The nitrogen content of microorganisms discharged from the bioreactor is in kg / d. R t is the standard oxygen demand of sewage at time t, in kgO2 / d, C S is the saturated dissolved oxygen in clean water under standard conditions, α is K in the mixed solution La Value and K in clean water La The ratio of values, β is the ratio of the saturated dissolved oxygen value of the mixed solution to the saturated dissolved oxygen value of the clean water. C stn,t The average dissolved oxygen in the clean water from the underwater depth to the pool surface of the aeration device at time t, in mg / L. C o is the residual dissolved oxygen concentration of the mixed solution, T is the temperature of the mixed liquid, Gs out,t is the oxygen flow rate at the aerator outlet at time t, is the oxygen density, in g / m 3 , E A is the oxygen utilization rate of the aerator (%).

9. The capacity configuration optimization method of the wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment model according to claim 8 is characterized by: In S3), the water reservoir constraint conditions are as follows: In the formula, Q out,t is the outflow rate of sewage from the reservoir at time t, Q out,min is the minimum outflow rate of sewage from the reservoir, Q out,max is the maximum outflow rate of sewage from the reservoir, Q in,t is the inflow flow rate of sewage into the reservoir at time t, Q in,min is the minimum inflow flow rate of sewage into the reservoir, Q in,max is the maximum inflow flow of sewage into the reservoir, Cap ct,t-1 is the capacity of the reservoir at time t-1, Cap ct,t is the capacity of the reservoir at time t, Cap ct,min The minimum volume of sewage that the reservoir can hold. Cap ct,max The maximum volume of sewage that the reservoir can hold; Cap ct,1 is the initial sewage volume of the reservoir; Cap ct,T Optimize the sewage volume at the end of the cycle for the water storage tank.

10. The capacity configuration optimization method of the wind-solar hydrogen production coupled with pure oxygen aeration sewage treatment model according to claim 1 is characterized by: In S4), the solver is Gurobi or CPLEX.

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