CN107500388B - Method and device for controlling conductivity in electrochemical treatment process of heavy metal wastewater - Google Patents

Method and device for controlling conductivity in electrochemical treatment process of heavy metal wastewater Download PDF

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CN107500388B
CN107500388B CN201710723539.3A CN201710723539A CN107500388B CN 107500388 B CN107500388 B CN 107500388B CN 201710723539 A CN201710723539 A CN 201710723539A CN 107500388 B CN107500388 B CN 107500388B
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heavy metal
conductivity
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metal ions
wastewater
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CN107500388A (en
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阳春华
张凤雪
朱红求
李勇刚
桂卫华
陈俊名
李繁飙
王强
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Central South University
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    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
    • C02F1/461—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
    • C02F1/461—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
    • C02F1/46104—Devices therefor; Their operating or servicing
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/10—Inorganic compounds
    • C02F2101/20—Heavy metals or heavy metal compounds
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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    • Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
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Abstract

The present invention provides aA method and a device for controlling the conductivity in the electrochemical treatment process of heavy metal wastewater are disclosed, wherein the method comprises the following steps: establishing a material balance model with time lag and heavy metal ion molar concentration; establishing an electric energy consumption optimization model in the electrochemical treatment process of the heavy metal wastewater based on a material balance model with time lag and heavy metal ion molar concentration, so that the electric energy consumption is minimum under the condition that the concentration of the heavy metal ions at an outlet meets a preset threshold; obtaining detection data of the concentration of inlet heavy metal ions of wastewater to be treated in the electrolytic cell, and carrying out optimization solution on the power consumption optimization model by adopting a state transfer algorithm to obtain an optimal conductivity value under the condition that the concentration of outlet heavy metal ions meets a preset threshold value, thereby calculating Na required in a pretreatment process2SO4The amount of (c) added. The conductivity control method provided by the invention can coordinate and control the pretreatment process and the electrolysis process, can regulate and control the conductivity in real time, and has important significance for the optimization guidance of the electrochemical wastewater treatment process.

Description

Method and device for controlling conductivity in electrochemical treatment process of heavy metal wastewater
Technical Field
The invention relates to the technical field of electrochemistry, in particular to a method and a device for controlling conductivity in a heavy metal wastewater electrochemical treatment process.
Background
Industrial wastewater has become an important pollution source of water pollution and mainly comes from the production process of factories and mines. Heavy metal pollutants, especially cadmium, cobalt, nickel and the like, have great hazards of carcinogenesis, teratogenesis and the like, and China also has strict standards for the discharge of the heavy metal pollutants. The electrochemical advanced treatment technology has high efficiency, simple and convenient operation and environmental compatibility, and can effectively remove heavy metal ions in water. The reaction conditions are adjusted at any time through the applied current and voltage, so that the controllability is strong; the electron transfer is only carried out between the electrode and the waste water component, and no oxidation reducing agent is needed to be added additionally, so that the problem of secondary pollution caused by adding a medicament is avoided, and the air flotation, flocculation and disinfection effects are realized.
The process of treating heavy metal wastewater by the electrochemical technology consists of a pretreatment process and an electrolysis process, the conductivity is an important factor influencing the wastewater treatment effect, and the conductivity needs to be adjusted to an optimal state in advance in the pretreatment process to ensure that the electrolysis process achieves the best treatment effect. However, the solution has a great time lag from the pretreatment process to the electrolysis process, and the electrode plates are continuously dissolved in the process, so that the distance between the electrode plates is continuously increased, and the change of the state of the electrolytic cell causes the change of the electrochemical reaction rate, thereby causing the difficulty in adjusting the conductivity and further influencing the treatment effect of the concentration of heavy metal ions at the outlet.
In the actual electrochemical wastewater treatment process, the setting of the conductivity is often determined according to manual experience, the problems of time delay of wastewater flowing from the pretreatment process to the electrolytic cell, electrode plate consumption and electric energy optimization are not considered, the influence of the operation state of the electrolytic cell on the electrochemical reaction efficiency is ignored, and the heavy metal wastewater treatment effect is poor and the energy is wasted.
Disclosure of Invention
In order to at least partially overcome the problems in the prior art, the invention provides a method and a device for controlling the conductivity in the electrochemical treatment process of heavy metal wastewater.
According to one aspect of the invention, the invention provides a method for controlling the conductivity in the electrochemical treatment process of heavy metal wastewater, which comprises the following steps: s1, establishing a band time based on the mass conservation law and Faraday law of material flowA material balance model of the molar concentration of the stagnant heavy metal ions; s2, establishing an electric energy consumption optimization model in the electrochemical treatment process of the heavy metal wastewater based on the heavy metal ion molar concentration material balance model with time lag, so that the electric energy consumption is minimum under the condition that the concentration of the outlet heavy metal ions meets a preset threshold; s3, obtaining detection data of the concentration of heavy metal ions at the inlet of the wastewater to be treated in the electrolytic cell, and carrying out optimization solution on the power consumption optimization model by adopting a state transfer algorithm to obtain the optimal conductivity value under the condition that the concentration of heavy metal ions at the outlet meets a preset threshold value, thereby calculating Na required in the pretreatment process2SO4The amount of (c) added.
The material balance model with time lag for the molar concentration of the heavy metal ions is specifically as follows:
Figure BDA0001385491290000021
wherein the content of the first and second substances,
Figure BDA0001385491290000022
is the change rate of the molar concentration of the heavy metal ions A in the electrolytic bath;
Figure BDA0001385491290000023
is the inlet molarity of heavy metal ion a; τ is the time required for the electrolyte to flow from the pretreatment process to the cell; cA(t) is the molar concentration of heavy metal ion a in the electrolytic cell; f is the flow rate of the inlet solution; v is the volume of the cell; r isAIs the electrochemical reaction rate of the heavy metal ions A in the electrolytic cell.
Wherein, the dynamic model of the electrochemical reaction rate of the heavy metal ions A in the electrolytic bath is specifically as follows:
Figure BDA0001385491290000024
wherein S is the area of the polar plate; u is electrolysis voltage; kappa is the conductivity; z is the number of charges transferred by electrode reaction, and takes a positive value; f is the Faraday constant；L0Is the initial spacing of the plates; r is the radius of an iron atom; v is the volume of the cell; n is a radical ofAIs an avogalois constant;
Figure BDA0001385491290000031
is the initial molar concentration of A ions, β1Is a parameter to be identified; j is the electrolytic current density.
The electric energy consumption optimization model specifically comprises the following steps:
Figure BDA00013854912900000312
Figure BDA0001385491290000032
wherein W is the power consumption; m is the number of the cathode plates; s is the area of each cathode plate; u is the cell voltage; t is t0And tfRespectively starting and ending the electrolysis;
Figure BDA0001385491290000033
is the outlet heavy metal ion A concentration; j is the current density; kappa is the conductivity; l is the distance between the polar plates;
Figure BDA0001385491290000034
the concentration of the heavy metal ions A at the outlet of the wastewater is an index value which is required to be reached; u shapemaxThe upper limit of the voltage that the electrode plate can bear.
Wherein, the cell voltage U and the heavy metal ion concentration C in the electric energy consumption optimization modelAAnd the relationship between the current density J is as follows:
Figure BDA0001385491290000035
wherein the content of the first and second substances,
Figure BDA0001385491290000036
is the equilibrium potential constant of A ion precipitation; v is the volume of the cell; s is the area of the polar plate; r is heat powerLearning a constant; f is a Faraday constant;
Figure BDA0001385491290000037
is the initial molarity of the a ions; l is0Is the initial spacing of the plates; t is the electrolysis temperature; r is the activity coefficient of the A ion; mAIs the relative atomic weight of heavy metal A α1～α5Is the parameter to be identified.
Wherein Na required in the pretreatment step is calculated in S32SO4The specific steps of the addition amount of (A) are as follows:
s31, obtaining the molar conductivity of the solution according to the Korlao Ussue empirical equation, and calculating to obtain Na when the conductivity is kappa2SO4Molar concentration of (a):
Figure BDA0001385491290000038
wherein the content of the first and second substances,
Figure BDA0001385491290000039
is Na2SO4The molar conductivity of the solution is related to the conductivity κ
Figure BDA00013854912900000310
CαIs Na2SO4The molar concentration of (c);
Figure BDA00013854912900000311
is Na2SO4The limiting molar conductivity of the solution, generally obtained by extrapolation, β being a constant;
s32, according to the Na2SO4The required Na is calculated according to the molar concentration of the sodium hydroxide2SO4The addition amount of (A) is specifically as follows:
mα＝CαMαV
wherein m isαIs desired Na2SO4The mass of addition of (c); mαIs Na2SO4The molar mass of (a); v is the volume of the electrolytic cell.
According to another aspect of the present invention, there is provided an apparatus for controlling conductivity in an electrochemical treatment process of heavy metal wastewater, comprising: the first model establishing unit is used for establishing a heavy metal ion molar concentration material balance model with time lag based on a mass conservation law and a Faraday law of material flow; the second model establishing unit is used for establishing an electric energy consumption optimization model in the electrochemical treatment process of the heavy metal wastewater based on the heavy metal ion molar concentration material balance model with time lag, so that the electric energy consumption is minimum under the condition that the concentration of the heavy metal ions at the outlet meets a preset threshold; the control unit is used for acquiring detection data of the concentration of the inlet heavy metal ions of the wastewater to be treated in the electrolytic cell, and performing optimization solution on the electric energy consumption optimization model by adopting a state transfer algorithm to obtain an optimal conductivity value under the condition that the concentration of the outlet heavy metal ions meets a preset threshold value, so that Na required in a pretreatment process is calculated2SO4The amount of (c) added.
Wherein, include: a first calculating unit for obtaining the molar conductivity of the solution according to the Korla Ussure empirical equation and calculating to obtain Na when the conductivity is kappa2SO4Molar concentration of (a):
Figure BDA0001385491290000041
wherein the content of the first and second substances,
Figure BDA0001385491290000042
is Na2SO4The molar conductivity of the solution is related to the conductivity κ
Figure BDA0001385491290000043
CαIs Na2SO4The molar concentration of (c);
Figure BDA0001385491290000044
is Na2SO4β is a constant;
second oneA calculation unit for calculating based on the Na2SO4The required Na is calculated according to the molar concentration of the sodium hydroxide2SO4The addition amount of (A) is specifically as follows:
mα＝CαMαV
wherein m isαIs desired Na2SO4The mass of addition of (c); mαIs Na2SO4The molar mass of (a); v is the volume of the electrolytic cell.
The heavy metal ion molar concentration material balance model with time lag established by the first model establishing unit specifically comprises the following steps:
Figure BDA0001385491290000051
wherein the content of the first and second substances,
Figure BDA0001385491290000052
is the change rate of the molar concentration of the heavy metal ions A in the electrolytic bath;
Figure BDA0001385491290000053
is the inlet molarity of heavy metal ion a; τ is the time required for the electrolyte to flow from the pretreatment process to the cell; cA(t) is the molar concentration of heavy metal ion a in the electrolytic cell; f is the flow rate of the inlet solution; v is the volume of the cell; r isAIs the electrochemical reaction rate of the heavy metal ions A in the electrolytic cell.
The electric energy consumption optimization model established by the second model establishing unit specifically comprises:
Figure BDA0001385491290000054
Figure BDA0001385491290000055
wherein W is the power consumption; m is the number of the cathode plates; s is the area of each cathode plate; u is the cell voltage; t is t0And tfAre respectively electricityTime of solution start and end;
Figure BDA0001385491290000056
is the outlet heavy metal ion A concentration; j is the current density; kappa is the conductivity; l is the distance between the polar plates;
Figure BDA0001385491290000057
the concentration of the heavy metal ions A at the outlet of the wastewater is an index value which is required to be reached; u shapemaxThe upper limit of the voltage that the electrode plate can bear.
In conclusion, the method for controlling the conductivity in the electrochemical treatment process of the heavy metal wastewater provided by the invention establishes a material balance model with the time-lag heavy metal ion molar concentration; establishing an electric energy consumption optimization model in the electrochemical treatment process of the heavy metal wastewater based on a material balance model with time lag and heavy metal ion molar concentration, so that the electric energy consumption is minimum under the condition that the concentration of the heavy metal ions at an outlet meets a preset threshold; obtaining detection data of the concentration of inlet heavy metal ions of wastewater to be treated in the electrolytic cell, and carrying out optimization solution on the power consumption optimization model by adopting a state transfer algorithm to obtain an optimal conductivity value under the condition that the concentration of outlet heavy metal ions meets a preset threshold value, thereby calculating Na required in a pretreatment process2SO4The amount of (c) added. The method for controlling the conductivity in the electrochemical treatment process of the heavy metal wastewater, which is provided by the embodiment, can coordinate and control the pretreatment process and the electrolysis process, regulate and control the conductivity in real time, and has important significance for optimization guidance of the electrochemical wastewater treatment process.
Drawings
FIG. 1 is a flow chart of a method for controlling conductivity in an electrochemical treatment process of heavy metal wastewater according to an embodiment of the invention;
FIG. 2 is a graph illustrating the outlet heavy metal ion concentration according to an embodiment of the present invention;
fig. 3 is a block diagram illustrating an apparatus for controlling conductivity in an electrochemical treatment process of heavy metal wastewater according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be described below with reference to the accompanying drawings, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Fig. 1 is a flow chart of a method for controlling conductivity in an electrochemical treatment process of heavy metal wastewater according to an embodiment of the invention, as shown in fig. 1, including:
s1, establishing a heavy metal ion molarity material balance model with time lag based on the mass conservation law and Faraday law of material flow;
preferably, a material balance model with time-lag heavy metal ion molar concentration reflecting the relationship among the concentration of heavy metal ions in the wastewater of the electrolytic cell, the conductivity of the wastewater, the distance between polar plates and the current density is established based on the mass conservation law and the Faraday law of material flow in the chemical production process.
S2, establishing an electric energy consumption optimization model in the electrochemical treatment process of the heavy metal wastewater based on the heavy metal ion molar concentration material balance model with time lag, so that the electric energy consumption is minimum under the condition that the concentration of the outlet heavy metal ions meets a preset threshold;
preferably, establishing an electrochemical reaction process electric energy optimization model taking minimum electric energy consumption as a target, conductivity as a control quantity and outlet heavy metal ion concentration reaching the standard as constraint conditions, so that the electric energy consumption is minimum under the condition that the outlet heavy metal ion concentration meets a preset threshold;
s3, obtaining detection data of the concentration of heavy metal ions at the inlet of the wastewater to be treated in the electrolytic cell, and carrying out optimization solution on the power consumption optimization model by adopting a state transfer algorithm to obtain the optimal conductivity value under the condition that the concentration of heavy metal ions at the outlet meets a preset threshold value, thereby calculating Na required in the pretreatment process2SO4The amount of (c) added.
Wherein, the process of treating the heavy metal wastewater by the electrochemical technology consists of a pretreatment process and an electrolysis process.
Preferably, the electric energy consumption optimization model is used for solving and obtaining the optimal conductivity value under the condition that the concentration of the outlet heavy metal ions meets the preset threshold value, so that a basis is provided for adjusting the conductivity, the concentration of the outlet heavy metal ions is stabilized, and electric energy and raw material resources are saved.
The embodiment provides a method for controlling the conductivity in the electrochemical treatment process of heavy metal wastewater, which comprises the steps of establishing a heavy metal ion molar concentration material balance model with time lag; establishing an electric energy consumption optimization model in the electrochemical treatment process of the heavy metal wastewater based on a material balance model with time lag and heavy metal ion molar concentration, so that the electric energy consumption is minimum under the condition that the concentration of the heavy metal ions at an outlet meets a preset threshold; obtaining detection data of the concentration of inlet heavy metal ions of wastewater to be treated in the electrolytic cell, and carrying out optimization solution on the power consumption optimization model by adopting a state transfer algorithm to obtain an optimal conductivity value under the condition that the concentration of outlet heavy metal ions meets a preset threshold value, thereby calculating Na required in a pretreatment process2SO4The amount of (c) added. The method for controlling the conductivity in the electrochemical treatment process of the heavy metal wastewater, which is provided by the embodiment, can coordinate and control the pretreatment process and the electrolysis process, regulate and control the conductivity in real time, and has important significance for optimization guidance of the electrochemical wastewater treatment process.
In another embodiment of the present invention, based on the above embodiment, the mass balance model with time lag for the molarity of heavy metal ions is specifically:
Figure BDA0001385491290000071
wherein the content of the first and second substances,
Figure BDA0001385491290000081
is the change rate of the molar concentration of the heavy metal ions A in the electrolytic bath;
Figure BDA0001385491290000082
is the inlet molarity of heavy metal ion a; τ is the time required for the electrolyte to flow from the pretreatment process to the cell; cA(t) is the molar concentration of heavy metal ion a in the electrolytic cell; f is the flow rate of the inlet solution; v is the volume of the cell; r isAIs the electrochemical reaction rate of the heavy metal ions A in the electrolytic cell.
Preferably, the change rate of the molar concentration of the heavy metal ions A in the electrolytic cell is obtained through a mass balance model of the molar concentration of the heavy metal ions with time lag.
In a further embodiment of the present invention, based on the above embodiment, the kinetic model of the electrochemical reaction rate of the heavy metal ion a in the electrolytic cell is specifically:
Figure BDA0001385491290000083
wherein S is the area of the polar plate; u is electrolysis voltage; kappa is the conductivity; z is the number of charges transferred by electrode reaction, and takes a positive value; f is a Faraday constant; l is0Is the initial spacing of the plates; r is the radius of an iron atom; v is the volume of the cell; n is a radical ofAIs an avogalois constant;
Figure BDA0001385491290000084
is the initial molar concentration of A ions, β1Is a parameter to be identified; j is the electrolytic current density.
Preferably, the kinetic model of the electrochemical reaction rate of the heavy metal ions A in the electrolytic cell provides a basis for establishing a mass balance model of the molar concentration of the heavy metal ions with time lag.
In another embodiment of the present invention, based on the above embodiment, the electric energy consumption optimization model specifically includes:
Figure BDA0001385491290000085
Figure BDA0001385491290000086
wherein W is the power consumption; m is the number of the cathode plates; s is the area of each cathode plate; u is the cell voltage; t is t0And tfRespectively starting and ending the electrolysis;
Figure BDA0001385491290000087
is the outlet heavy metal ion A concentration; j is the current density; kappa is the conductivity; l is the distance between the polar plates;
Figure BDA0001385491290000091
the concentration of the heavy metal ions A at the outlet of the wastewater is an index value which is required to be reached; u shapemaxThe upper limit of the voltage that the electrode plate can bear.
Preferably, an electric energy consumption optimization model of the electrochemical reaction process is established, wherein the electric energy consumption is minimum, the conductivity is used as a control quantity, and the concentration of the outlet heavy metal ions reaches the standard and is used as a constraint condition, so that the electric energy consumption is minimum under the condition that the concentration of the outlet heavy metal ions meets a preset threshold value.
In another embodiment of the present invention, based on the above embodiments, the cell voltage U and the heavy metal ion concentration C in the electric energy consumption optimization modelAAnd the relationship between the current density J is as follows:
Figure BDA0001385491290000092
wherein the content of the first and second substances,
Figure BDA0001385491290000093
is the equilibrium potential constant of A ion precipitation; v is the volume of the cell; s is the area of the polar plate; r is a thermodynamic constant; f is a Faraday constant;
Figure BDA0001385491290000094
is the initial molarity of the a ions; l is0Is the initial spacing of the plates; t is the electrolysis temperature; r is the activity coefficient of the A ion; mAIs the relative atomic weight of heavy metal A α1～α5Is the parameter to be identified.
Preferably, the cell voltage U and the concentration C of heavy metal ionsAAnd the relational expression among the current densities J provides a basis for establishing an electric energy consumption optimization model.
In another embodiment of the present invention, based on the above embodiment, the Na required in the pretreatment process is calculated in S32SO4The specific steps of the addition amount of (A) are as follows:
s31, obtaining the molar conductivity of the solution according to the Korlao Ussue empirical equation, and calculating to obtain Na when the conductivity is kappa2SO4Molar concentration of (a):
Figure BDA0001385491290000095
wherein the content of the first and second substances,
Figure BDA0001385491290000096
is Na2SO4The molar conductivity of the solution is related to the conductivity κ
Figure BDA0001385491290000097
CαIs Na2SO4The molar concentration of (c);
Figure BDA0001385491290000098
is Na2SO4β is a constant;
s32, according to the Na2SO4The required Na is calculated according to the molar concentration of the sodium hydroxide2SO4The addition amount of (A) is specifically as follows:
mα＝CαMαV
wherein m isαIs desired Na2SO4The mass of addition of (c); mαIs Na2SO4The molar mass of (a); v is the volume of the electrolytic cell.
Preferably, by calculating the Na required in the pretreatment process2SO4Can make the concentration of heavy metal ions at the outlet meet a preset thresholdThe electric energy consumption is minimum under the condition, and raw materials are saved.
The method provided by the above embodiment is explained below by a specific example.
For antimony-containing heavy metal industrial wastewater to be treated, wherein the content of antimony is 180mg/L, the conductivity is 1.06s/m, a continuous water feeding mode is adopted, the flow rate is controlled to be 55m3/h, and the time for the wastewater to flow from the pretreatment tank to the electrolytic tank is 10 min. The conductivity value of the wastewater to be treated is dynamically adjusted in real time by adopting the conductivity control method in the electrochemical treatment process of the heavy metal wastewater provided by the embodiment, so that the concentration of the antimony ions at the outlet reaches 0.5 mg/L. Firstly, constructing a material balance model with time lag and heavy metal ion molar concentration based on a mass conservation law and a Faraday law of material flow in a chemical production process; secondly, establishing an electric energy optimization model of the electrochemical reaction process, which takes the minimum electric energy consumption as a target, takes the electric conductivity as a control quantity and takes the concentration of the outlet heavy metal ions up to the standard as constraint conditions, so that the electric energy consumption is minimum under the condition that the concentration of the outlet heavy metal ions meets a preset threshold value; thirdly, obtaining detection data of the concentration of the inlet heavy metal ions of the wastewater to be treated in the electrolytic bath, carrying out optimization solution by adopting a state transfer algorithm to obtain the optimal conductivity value under the condition that the concentration of the outlet heavy metal ions meets a preset threshold value, and calculating Na required by the pretreatment process2SO4The amount of (c) added.
Controlling the conductivity of the heavy metal wastewater in 24 hours by adopting a conductivity control method in the electrochemical treatment process, comparing by adopting a manual regulation method, and obtaining Na by adopting the two methods2SO4The amount of addition and the power consumption were compared, as shown in Table 1, and the outlet antimony ion concentration was as shown in FIG. 2. As can be seen from Table 1 and FIG. 2, the conductivity control method for the electrochemical treatment process of heavy metal wastewater can coordinate and control the pretreatment process and the electrochemical process, and regulate and control the conductivity in real time, so that the Na is optimized under the condition that the concentration of the heavy metal ions at the outlet meets the preset threshold value2SO4The amount of (c) added.
TABLE 1 Na2SO4Addition amount and electric energy consumption comparison
Operated manually Optimizing control operations
Na2SO4Addition amount (kg) 2400 2290.6
Power consumption (kW. h) 1390.09 1263.2
The embodiment provides a method for controlling the conductivity in the electrochemical treatment process of heavy metal wastewater, which can coordinate and control a pretreatment process and an electrolysis process, can regulate and control the conductivity in real time, and has important significance for optimization guidance of the electrochemical wastewater treatment process.
Fig. 3 is a block diagram of a device for controlling conductivity in an electrochemical treatment process of heavy metal wastewater according to an embodiment of the present invention, as shown in fig. 3, including: a first model establishing unit 301, a second model establishing unit 302 and a control unit 303; wherein the content of the first and second substances,
the first model establishing unit 301 is configured to establish a heavy metal ion molarity material balance model with time lag based on a mass conservation law and a faraday law of material flow;
preferably, a material balance model with time-lag heavy metal ion molar concentration reflecting the relationship among the concentration of heavy metal ions in the wastewater of the electrolytic cell, the conductivity of the wastewater, the distance between polar plates and the current density is established based on the mass conservation law and the Faraday law of material flow in the chemical production process.
The second model establishing unit 302 is configured to establish an electric energy consumption optimization model in the electrochemical treatment process of the heavy metal wastewater based on the time-lag heavy metal ion molar concentration material balance model, so that electric energy consumption is minimum when the concentration of the outlet heavy metal ions meets a preset threshold;
preferably, establishing an electrochemical reaction process electric energy optimization model taking minimum electric energy consumption as a target, conductivity as a control quantity and outlet heavy metal ion concentration reaching the standard as constraint conditions, so that the electric energy consumption is minimum under the condition that the outlet heavy metal ion concentration meets a preset threshold;
the control unit 303 is configured to obtain detection data of the concentration of the inlet heavy metal ions of the wastewater to be treated in the electrolytic cell, perform optimization solution on the power consumption optimization model by using a state transfer algorithm, obtain an optimal conductivity value under the condition that the concentration of the outlet heavy metal ions meets a preset threshold, and calculate Na required in a pretreatment process2SO4The amount of (c) added.
Preferably, the electric energy consumption optimization model is used for solving and obtaining the optimal conductivity value under the condition that the concentration of the outlet heavy metal ions meets the preset threshold value, so that a basis is provided for adjusting the conductivity, the concentration of the outlet heavy metal ions is stabilized, and electric energy and raw material resources are saved.
The embodiment provides a control device for conductivity in an electrochemical treatment process of heavy metal wastewater, which comprises a first model establishing unit, a second model establishing unit and a control unit, wherein the first model establishing unit is used for establishing a material balance model with time lag and heavy metal ion molar concentration; the second model establishing unit is used for establishing an electric energy consumption optimization model in the electrochemical treatment process of the heavy metal wastewater based on the heavy metal ion molar concentration material balance model with time lag, so that the electric energy consumption is minimum under the condition that the concentration of the outlet heavy metal ions meets a preset threshold; the control unit is used for acquiring detection data of the concentration of the inlet heavy metal ions of the wastewater to be treated in the electrolytic cell, and performing optimization solution on the power consumption optimization model by adopting a state transfer algorithm to obtain the concentration of the outlet heavy metal ions meeting a preset threshold valueThe optimum value of the conductivity in the case of (1), thereby calculating Na required in the pretreatment process2SO4The amount of (c) added. The control device for the conductivity in the electrochemical treatment process of the heavy metal wastewater provided by the embodiment can coordinate and control the pretreatment process and the electrolysis process, can regulate and control the conductivity in real time, and has important significance for optimization guidance of the electrochemical wastewater treatment process.
In another embodiment of the present invention, on the basis of the above embodiment, the method includes:
a first calculating unit for obtaining the molar conductivity of the solution according to the Korla Ussure empirical equation and calculating to obtain Na when the conductivity is kappa2SO4Molar concentration of (a):
Figure BDA0001385491290000121
wherein the content of the first and second substances,
Figure BDA0001385491290000122
is Na2SO4The molar conductivity of the solution is related to the conductivity κ
Figure BDA0001385491290000123
CαIs Na2SO4The molar concentration of (c);
Figure BDA0001385491290000124
is Na2SO4The limiting molar conductivity of the solution, generally obtained by extrapolation, β being a constant;
a second calculation unit for calculating the Na2SO4The required Na is calculated according to the molar concentration of the sodium hydroxide2SO4The addition amount of (A) is specifically as follows:
mα＝CαMαV
wherein m isαIs desired Na2SO4The mass of addition of (c); mαIs Na2SO4The molar mass of (a); v is the volume of the electrolytic cell.
Preferably, by calculating the Na required in the pretreatment process2SO4The addition amount of (2) can ensure that the power consumption is optimal and minimum under the condition that the concentration of the heavy metal ions at the outlet meets the preset threshold value, and simultaneously, the raw materials are saved.
In another embodiment of the present invention, based on the above embodiment, the time-lag heavy metal ion molar concentration material balance model established by the first model establishing unit specifically includes:
Figure BDA0001385491290000131
wherein the content of the first and second substances,
Figure BDA0001385491290000132
is the change rate of the molar concentration of the heavy metal ions A in the electrolytic bath;
Figure BDA0001385491290000133
is the inlet molarity of heavy metal ion a; τ is the time required for the electrolyte to flow from the pretreatment process to the cell; cA(t) is the molar concentration of heavy metal ion a in the electrolytic cell; f is the flow rate of the inlet solution; v is the volume of the cell; r isAIs the electrochemical reaction rate of the heavy metal ions A in the electrolytic cell.
Preferably, the change rate of the molar concentration of the heavy metal ions A in the electrolytic cell is obtained through a mass balance model of the molar concentration of the heavy metal ions with time lag.
In another embodiment of the present invention, based on the above embodiment, the electric energy consumption optimization model established by the second model establishing unit specifically includes:
Figure BDA0001385491290000134
Figure BDA0001385491290000135
wherein W is the power consumption; m is the number of the cathode plates; s is each blockArea of the cathode plate; u is the cell voltage; t is t0And tfRespectively starting and ending the electrolysis;
Figure BDA0001385491290000136
is the outlet heavy metal ion A concentration; j is the current density; kappa is the conductivity; l is the distance between the polar plates;
Figure BDA0001385491290000137
the concentration of the heavy metal ions A at the outlet of the wastewater is an index value which is required to be reached; u shapemaxThe upper limit of the voltage that the electrode plate can bear.
Preferably, an electric energy consumption optimization model of the electrochemical reaction process is established, wherein the electric energy consumption is minimum, the conductivity is used as a control quantity, and the concentration of the outlet heavy metal ions reaches the standard and is used as a constraint condition, so that the electric energy consumption is minimum under the condition that the concentration of the outlet heavy metal ions meets a preset threshold value.
Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations fall within the scope defined by the appended claims.

Claims (5)

1. A method for controlling the conductivity in the electrochemical treatment process of heavy metal wastewater is characterized by comprising the following steps:
s1, establishing a heavy metal ion molarity material balance model with time lag based on the mass conservation law and Faraday law of material flow;
s2, establishing an electric energy consumption optimization model in the electrochemical treatment process of the heavy metal wastewater based on the heavy metal ion molar concentration material balance model with time lag, so that the electric energy consumption is minimum under the condition that the concentration of the outlet heavy metal ions meets a preset threshold;
s3, obtaining detection data of the concentration of the inlet heavy metal ions of the wastewater to be treated in the electrolytic cell, and carrying out optimization solution on the power consumption optimization model by adopting a state transfer algorithm to obtain the condition that the concentration of the outlet heavy metal ions meets a preset threshold valueThe optimum value of the conductivity under the condition of the above-mentioned condition can be used for calculating Na required in the pretreatment procedure2SO4The amount of (c) added;
the heavy metal ion molar concentration material balance model with time lag specifically comprises the following steps:
Figure FDA0002242926360000011
wherein the content of the first and second substances,
Figure FDA0002242926360000012
is the change rate of the molar concentration of the heavy metal ions A in the electrolytic bath;
Figure FDA0002242926360000013
is the inlet molarity of heavy metal ion a; τ is the time required for the electrolyte to flow from the pretreatment process to the cell; cA(t) is the molar concentration of heavy metal ion a in the electrolytic cell; f is the flow rate of the inlet solution; v is the volume of the cell; r isAIs the electrochemical reaction rate of the heavy metal ions A in the electrolytic cell;
the dynamic model of the electrochemical reaction rate of the heavy metal ions A in the electrolytic cell is specifically as follows:
Figure FDA0002242926360000014
wherein S is the area of the polar plate; u is electrolysis voltage; kappa is the conductivity; z is the number of charges transferred by electrode reaction, and takes a positive value; f is a Faraday constant; l is0Is the initial spacing of the plates; r is the radius of an iron atom; v is the volume of the cell; n is a radical ofAIs an avogalois constant;
Figure FDA0002242926360000021
is the initial molar concentration of A ions, β1Is a parameter to be identified; j is the electrolysis current density;
the electric energy consumption optimization model specifically comprises the following steps:
Figure FDA0002242926360000022
Figure FDA0002242926360000023
wherein W is the power consumption; m is the number of the cathode plates; s is the area of each cathode plate; u is the cell voltage; t is t0And tfRespectively starting and ending the electrolysis;
Figure FDA0002242926360000024
is the outlet heavy metal ion A concentration; j is the current density; kappa is the conductivity L and the polar plate distance;
Figure FDA0002242926360000025
the concentration of the heavy metal ions A at the outlet of the wastewater is an index value which is required to be reached; u shapemaxThe upper limit of the voltage that the electrode plate can bear.
2. The method for controlling conductivity according to claim 1, wherein the cell voltage U and the heavy metal ion concentration C in the power consumption optimization modelAAnd the relationship between the current density J is as follows:
Figure FDA0002242926360000026
wherein the content of the first and second substances,
Figure FDA0002242926360000027
is the equilibrium potential constant of A ion precipitation; v is the volume of the cell; s is the area of the polar plate; r is a thermodynamic constant; f is a Faraday constant;
Figure FDA0002242926360000028
is the initial molarity of the a ions; l is0Is the initial spacing of the plates; t is the electrolysis temperature; r is the activity coefficient of the A ion; mAIs the relative atomic weight of heavy metal A α1～α5Is the parameter to be identified.
3. The method for controlling conductivity according to claim 1, wherein Na required for the pretreatment step is calculated in S32SO4The specific steps of the addition amount of (A) are as follows:
s31, obtaining the molar conductivity of the solution according to the Korlao Ussue empirical equation, and calculating to obtain Na when the conductivity is kappa2SO4Molar concentration of (a):
Figure FDA0002242926360000029
wherein, ΛαIs Na2SO4The molar conductivity of the solution is related to the conductivity kappa by the relationship of lambdaα＝κ/Cα；CαIs Na2SO4The molar concentration of (c);
Figure FDA0002242926360000031
is Na2SO4β is a constant;
s32, according to the Na2SO4The required Na is calculated according to the molar concentration of the sodium hydroxide2SO4The addition amount of (A) is specifically as follows:
mα＝CαMαV
wherein m isαIs desired Na2SO4The mass of addition of (c); mαIs Na2SO4The molar mass of (a); v is the volume of the electrolytic cell.
4. A control device of conductivity in heavy metal waste water electrochemical treatment process, characterized by includes:
the first model establishing unit is used for establishing a heavy metal ion molar concentration material balance model with time lag based on a mass conservation law and a Faraday law of material flow;
the second model establishing unit is used for establishing an electric energy consumption optimization model in the electrochemical treatment process of the heavy metal wastewater based on the heavy metal ion molar concentration material balance model with time lag, so that the electric energy consumption is minimum under the condition that the concentration of the heavy metal ions at the outlet meets a preset threshold;
the control unit is used for acquiring detection data of the concentration of the inlet heavy metal ions of the wastewater to be treated in the electrolytic cell, and performing optimization solution on the electric energy consumption optimization model by adopting a state transfer algorithm to obtain an optimal conductivity value under the condition that the concentration of the outlet heavy metal ions meets a preset threshold value, so that Na required in a pretreatment process is calculated2SO4The amount of (c) added;
the heavy metal ion molar concentration material balance model with time lag established by the first model establishing unit specifically comprises the following steps:
Figure FDA0002242926360000032
wherein the content of the first and second substances,
Figure FDA0002242926360000033
is the change rate of the molar concentration of the heavy metal ions A in the electrolytic bath;
Figure FDA0002242926360000034
is the inlet molarity of heavy metal ion a; τ is the time required for the electrolyte to flow from the pretreatment process to the cell; cA(t) is the molar concentration of heavy metal ion a in the electrolytic cell; f is the flow rate of the inlet solution; v is the volume of the cell; r isAIs the electrochemical reaction rate of the heavy metal ions A in the electrolytic cell;
the electric energy consumption optimization model established by the second model establishing unit specifically comprises:
Figure FDA0002242926360000041
Figure FDA0002242926360000042
wherein W is the power consumption; m is the number of the cathode plates; s is the area of each cathode plate; u is the cell voltage; t is t0And tfRespectively starting and ending the electrolysis;
Figure FDA0002242926360000043
is the outlet heavy metal ion A concentration; j is the current density; kappa is the conductivity; l is the distance between the polar plates;
Figure FDA0002242926360000044
the concentration of the heavy metal ions A at the outlet of the wastewater is an index value which is required to be reached; u shapemaxThe upper limit of the voltage that the electrode plate can bear.
5. The apparatus for controlling electric conductivity of claim 4, comprising:
a first calculating unit for obtaining the molar conductivity of the solution according to the Korla Ussure empirical equation and calculating to obtain Na when the conductivity is kappa2SO4Molar concentration of (a):
Figure FDA0002242926360000045
wherein, ΛαIs Na2SO4The molar conductivity of the solution is related to the conductivity kappa by the relationship of lambdaα＝κ/Cα；CαIs Na2SO4The molar concentration of (c);
Figure FDA0002242926360000046
is Na2SO4The limiting molar conductivity of the solution, generally obtained by extrapolation, β being a constant;
a second calculation unit for calculating the Na2SO4The required Na is calculated according to the molar concentration of the sodium hydroxide2SO4The addition amount of (A) is specifically as follows:
mα＝CαMαV
wherein m isαIs desired Na2SO4The mass of addition of (c); mαIs Na2SO4The molar mass of (a); v is the volume of the electrolytic cell.
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1883808A2 (en) * 2005-05-26 2008-02-06 Cymtox Limited Water monitoring system
CN101825870A (en) * 2010-05-18 2010-09-08 浙江浙大中控信息技术有限公司 Method and system for controlling supply quantity of water-treatment flocculating agent
CN102732723A (en) * 2012-06-20 2012-10-17 中南大学 Waste acid addition controlling method of zinc wet smelting cobalt-removing purifying process employing arsenic salt
CN104803452A (en) * 2015-04-09 2015-07-29 长沙华时捷环保科技发展有限公司 Automatic control method for electrochemistry heavy metal sewage treatment system
CN105955327A (en) * 2016-06-21 2016-09-21 中南大学 Coordinated control method and apparatus of heavy metal waste water processing process

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1883808A2 (en) * 2005-05-26 2008-02-06 Cymtox Limited Water monitoring system
CN101825870A (en) * 2010-05-18 2010-09-08 浙江浙大中控信息技术有限公司 Method and system for controlling supply quantity of water-treatment flocculating agent
CN102732723A (en) * 2012-06-20 2012-10-17 中南大学 Waste acid addition controlling method of zinc wet smelting cobalt-removing purifying process employing arsenic salt
CN104803452A (en) * 2015-04-09 2015-07-29 长沙华时捷环保科技发展有限公司 Automatic control method for electrochemistry heavy metal sewage treatment system
CN105955327A (en) * 2016-06-21 2016-09-21 中南大学 Coordinated control method and apparatus of heavy metal waste water processing process

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