KR102620496B1 - Verifying method for error analyzing of waterquality - Google Patents

Abstract

The present invention is an error verification method in raw water quality analysis that compares measured values by water quality measurement and theoretically calculated values using the measured values to determine whether they match within an allowable error range, wherein the measured values An electrical neutrality determination step of determining whether the electrical neutrality (ion balance) of the calculated value matches within the error range; A TDS determination step of determining whether the TDS (Total Dissolved Solid) of the measured value and the calculated value match within an error range; By presenting an error verification method for raw water quality analysis, including an electrical conductivity determination step of determining whether the electrical conductivity of the measured value and the calculated value matches within the error range, a simulator for designing a water treatment facility is provided. By identifying in advance errors in raw water quality analysis, which is the premise of , it is possible to design a water treatment facility with optimal process combination and treatment performance.

Description

{VERIFYING METHOD FOR ERROR ANALYZING OF WATERQUALITY}

The present invention relates to the field of environmental technology, and more specifically, to a method for verifying errors in the analysis of raw water quality in water purification plants.

The design of a water purification facility is to remove organic and inorganic substances in solid and dissolved states from water, and to design a purified water production facility that meets drinking water quality standards through removal and inactivation of pathogenic microorganisms.

This requires the convergence of various technologies such as fluid (water) flow dynamics, water chemistry, microorganisms, civil engineering for facilities, machinery, electricity, and instrumentation control.

In addition to the technical conditions listed above, water quality is not the same for each water source, and the climatic conditions, topographical conditions, and human and social conditions of the area where the water purification facility is installed are diverse, so the design of the water purification facility reflects these conditions and determines the water treatment process. Selection and design involve complex processes.

Therefore, because there cannot be identical designs due to various environmental conditions, most research on optimization and automation of facilities or facilities that require operation and operation is conducted on facilities that are in operation.

Moreover, facility operation is performed by local governments and public enterprises, and design is performed by private engineering companies, so problems at the operation stage are not smoothly fed back to the design, and even if feedback is provided, the condition cannot be simulated in advance at the operation stage. You can decide whether to apply it or not.

In addition, technologies such as unit process analysis and real-time water treatment process evaluation using big data and artificial intelligence produced at operating facilities are problematic because they assume that the data was produced at an optimized water treatment facility. Data produced in existing facilities must be evaluated in order to apply them to the design of new facilities.

For this reason, as shown in Figure 1, a physicochemical-based simulator based on theories established based on many research results from industry, academia, and research is needed.

Numerous studies have been conducted on water treatment simulators, and empirical formulas have been published through many experiments. In addition, physicochemical theories based on universal laws have been sufficiently established, making it possible to develop simulators through theory and numerical analysis. It has been done.

Additionally, remarkable developments in computer engineering are providing an environment for digital transformation.

In the past, uncontaminated raw water or clean groundwater could meet the “drinking water quality standards” through simple treatment, so purification was possible with simple processes of “filtration” and “disinfection” to remove solid substances in the water, but with industrialization, Raw water has been polluted with pollutants emitted from industrial wastewater, domestic sewage, agricultural and livestock wastewater, and fertilizers, and the substances that need to be removed have increased from solid substances to various organic substances, hormone substances, tastes and odors, pathogenic microorganisms, etc., such as chemical injection, precipitation, etc. Because processes such as advanced oxidation, activated carbon filtration, and membrane filtration are added and chemicals are added, water purification is achieved through complex functions not only in each unit process but also in continuous processes. However, the design still requires the target water quality items and treatments to be removed for each unit process. Without standards, the appropriateness of design and construction is judged solely on whether the final produced purified water meets the legal “drinking water quality standards.”

Therefore, in order to advance the design, a simulator was needed to predict the treatment level of substances to be removed by process and to simulate changes in water quality that occur in continuous processes.

Republic of Korea Patent Publication No. 10-2012-0117045, real-time water purification process evaluation system and method using a unit process analysis model Republic of Korea Patent Publication No. 2010-0124511, apparatus and method for predicting the generation results of disinfection by-products using an artificial neural network Republic of Korea Patent Publication No. 2010-0108738, complex disinfection system combining ozone and chlorine and complex disinfectant model prediction control method implemented through the system

The present invention was developed to solve the above problems, and by identifying in advance errors in raw water quality analysis, which is the premise of a simulator for water treatment facility design, it is possible to create a water treatment facility with optimal process combination and treatment performance. The purpose is to present an error verification method for raw water quality analysis that enables design.

In order to solve the above problem, the present invention compares the measured value by water quality measurement and the calculated value theoretically calculated using the measured value to determine whether the error in raw water quality analysis matches within the allowed error range. As a verification method, an electrical neutrality determination step of determining whether the electrical neutrality (ion balance) of the measured value and the calculated value matches within an error range; A TDS determination step of determining whether the TDS (Total Dissolved Solid) of the measured value and the calculated value match within an error range; We present an error verification method for raw water quality analysis, which includes an electrical conductivity determination step of determining whether the electrical conductivity of the measured value and the calculated value match within the error range.

In the step of determining electrical neutrality, it is preferable to obtain the calculated value using Equations 1 to 3.

[Equation 1]

TA≡2[CO ₃ ^2- ]+[HCO ₃ ^- ]+[H ₂ BO ₃ ^- ]+2[HBO ₃ ^2- ]+3[BO ₃ ^3- ]+[OH ^- ]+[organic/inorganic H ⁺ acceptors]-[H ⁺ ]

[Equation 2]

[H ⁺ ]=2[CO ₃ ^2- ]+[HCO ₃ ^- ]+[H ₂ BO ₃ ^- ]+2[HBO ₃ ^2- ]+3[BO ₃ ^3- ]+[OH ^- ]+[organic /inorganic H ⁺ acceptors]

[Equation 3]

{(Total positive ions - Total negative ions)/(Total positive ions + Total negative ions)}×100 (%) = Electrical neutrality

In the TDS determination step, it is preferable to obtain the calculated value using Equation 4.

[Equation 4]

TDS, mg/L = [Na ⁺ + K ⁺ + Ca ²⁺ + Mg ²⁺ + Cl ^- + NO ₃ ^- + SiO ₃ ^2- + F ^- + 0.6×alkalinity (as CaCO ₃ )] mg/L

In the step of determining electrical conductivity, it is preferable to obtain the calculated value using Equation 5.

[Equation 5]

G _o ⁺ = ∑(C ⁺ × λ ⁺ )

G _o ^- = ∑(C ^- × λ ^- )

Z ⁺ = (∑C ⁺ ×z ² )/(∑C ⁺ ×z)

Z ^- = (∑C ^- ×z ² )/(∑C ^- ×z)

Λ ^o (total ionic conductance) = G _o ⁺ + G _o ^-

Λ ⁺ = G _o ⁺ /∑C _o ⁺

Λ ^- = G _o ^- /∑C _o ^-

Q = (Λ ^o × Z ^- × Z ⁺ )/{(Z ⁺ + Z ^- ) × (Z ⁺ ×Λ ^- + Z ^- × Λ ⁺ )}

C ^o = (∑C ⁺ + ∑C ^- )/2

Term1 = G _o ⁺ + G _o ^- = ∑(C ⁺ × λ ⁺ ) + ∑(C ^- × λ ^- )

Term2 = (Λ ^o × Z ^- × Z ⁺ )/{115.2 × (Z ^- + Z ⁺ )}

Term3 = (2 × Q) / (1+√Q)

Term4 = {(Z ^- + Z ⁺ ) × C ^o } ^1.5 = {(Z ^- + Z ⁺ ) × (∑C ⁺ +∑C ^- /2)} ^1.5

EC = Term1-(Term2 × Term3) + 0.668 × Term4

C ^+(-) : Normality (N) concentration (Normality, mili-equivalent/L, meq/L)

z ^+(-) : Absolute value of ionic value

λ ^+(-) : Electrical conductivity of ions

The present invention is a method for verifying errors in raw water quality analysis that enables the design of a water treatment facility with optimal process combination and treatment performance by identifying errors in raw water quality analysis in advance, which is the premise of a simulator for water treatment facility design. presents.

1 and below show an embodiment of the present invention,
Figure 1 is an overview of the importance and location of the water treatment simulator in CPS and Digital twin, the 4th industrial revolution technology.
Figure 2 is a schematic diagram of the simulator framework.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The present invention relates to an error verification method for raw water quality analysis that compares measured values by water quality measurement and calculated values theoretically calculated using the measured values to determine whether they match within the allowable error range.

This includes an electrical neutrality determination step of determining whether the electrical neutrality (ion balance) of the measured value and the calculated value match within the error range; A TDS determination step to determine whether the TDS (Total Dissolved Solid) of the measured value and the calculated value match within the error range; It includes an electrical conductivity determination step of determining whether the electrical conductivity of the measured value and the calculated value match within the error range.

According to research results to date, the above error range has been shown to be appropriate within 2% for electrical neutrality (ion balance), within 5% for TDS, and within 3% for electrical conductivity.

Water treatment process design is performed based on the water quality test results of raw water.

If there is an error in raw water quality analysis, it can result in incorrect process selection and combination, and it can be determined whether there has been an unexpected water quality accident at the water intake source.

As a method of verifying errors in the analysis of raw water quality, it is determined whether the water quality measured in the laboratory and in the field is within the theoretical tolerance range of the calculated value using the physical and chemical universal laws of water.

Even though the water quality test was conducted legally, the large error means that chemicals were artificially added to the natural raw water or there was an accident. Because enemies are in equilibrium.

Define water quality variables, which are independent variables to be input into the simulator, and dependent variables, which are target dependent variables in each process.

Water quality items are test data to verify input data for each condition and values output from the simulator, and are data measured or sampled directly from raw water and analyzed in a laboratory.

Table 1 relates to raw water quality items.

The 'data validation' of [M30] in Figure 2, which is a simulator framework, is based on the water quality test results provided by [M12] and the water chemical properties, electrical neutrality, TDS and electrical conductivity formulas from the library of [M20]. It is calculated using and compared with the actual measured value to determine whether it is within the allowable value.

Hereinafter, an embodiment of a specific determination method regarding whether the electrical neutrality (ion balance), TDS (Total Dissolved Solid), and electrical conductivity of the measured and calculated values match within the error range will be described.

(1) Electrical neutrality (ion balance) determination step

Alkalinity is contained in water in the form of hydroxide (OH ^- ), carbonate (CO ₃ ^2- ), and bicarbonate (HCO ₃ ^2- ), which neutralize acids. Since it is difficult to measure all of them, alkalinity is used to measure alkalinity accordingly. It is expressed in terms of CaCO ₃ and is a measure of the ability needed to neutralize acids in water.

Components of alkalinity in natural water systems include CO ₃ ^2- , HCO ₃ ^- , OH ^- as well as H ₂ BO ₃ ^- , HPO ₄ ^2- , H ₂ PO ₄ ^- , HS ^- and NH ₃ .

Alkalinity can be directly converted to negative ions as follows.

At this time, care must be taken to ensure that components included in alkalinity are not double reflected in the total anion concentration.

Normal concentration (meq/L) = (water quality measurement value (mg/L)/equivalent), and since the molecular weight of CaCO ₃ is 100g/mol and the valence is 2eq/mol, the equivalent weight is 50eq.

The major contribution to alkalinity is in the following order: hydroxide > carbonate > bicarbonate.

Total Alkalinity (TA) is expressed in Equation 1 below.

[Equation 1]

TA≡2[CO ₃ ^2- ]+[HCO ₃ ^- ]+[H ₂ BO ₃ ^- ]+2[HBO ₃ ^2- ]+3[BO ₃ ^3- ]+[OH ^- ]+[organic/inorganic H ⁺ acceptors]-[H ⁺ ]
TA: Total Alkalinity
[organic/inorganic H ⁺ acceptors]: Organic and/or inorganic electron acceptors
TA stands for Total Alkalinity.
Alkalinity indicates the ability to neutralize acids, and is expressed by the Balance chemical equation (Proton balance + Charge balance) of substances exchanging and receiving electrons of H ⁺ ions according to the Brønsted-Lowry acid/base theory.
Typical alkaline components that indicate alkalinity include carbonates [CO ₃ ^2- ], hydrogen carbonates [HCO ₃ ^- ], and hydroxides [OH ^- ]. In addition, anions such as Borate [BO ₃ ^3- ] and Silicate [SiO The amount of _4-x ^(4-2x)- ], Phosphate[PO ₄ ^3- ] also affects alkalinity.
[organic/inorganic H ⁺ acceptors] refers to organic and/or inorganic electron acceptors.
Organic and/or inorganic electron acceptors are substances that can accept electrons (H ⁺ ) from other molecules in chemical reactions.
According to the Brønsted-Lowry theory, it corresponds to the Brønsted-Lowry base.
There are various types of electron acceptor materials, and since it is difficult to list all types in this equation, electron acceptor materials are expressed as [organic/inorganic H ⁺ acceptors].
Organic electron acceptors (Organic H ⁺ acceptors) include ethers, aldehydes, ketones, and esters.
Inorganic electron acceptors (Inorganic H ⁺ acceptors) include fluorine ions, hydroxide ions, carbonate ions, and sulfide ions.

The final titration of alkalinity using an acidic titrant is as follows:

[Equation 2]

[H ⁺ ]=2[CO ₃ ^2- ]+[HCO ₃ ^- ]+[H ₂ BO ₃ ^- ]+2[HBO ₃ ^2- ]+3[BO ₃ ^3- ]+[OH ^- ]+[organic /inorganic H ⁺ acceptors]

Total alkalinity is usually expressed as meq/L or meq/kg, and eq (equivalent) refers to the valence (electron) of 1 mole.

When calculating alkalinity according to Equation 1 or Equation 2, the sum of cations and anions is obtained in Table 2.

Table 2 relates to water quality analysis and N concentration of cations and anions.

Calculate the neutrality of cations and anions from Equation 3 and determine whether it is appropriate.

[Equation 3]

{(Total positive ions - Total negative ions)/(Total positive ions + Total negative ions)}×100 (%) = Electrical neutrality

(2) TDS judgment stage

The total dissolved solids are obtained from Equation 4 and the difference from the measured value is determined to determine whether it is appropriate.

[Equation 4]

TDS, mg/L = [Na ⁺ + K ⁺ + Ca ²⁺ + Mg ²⁺ + Cl ^- + NO ₃ ^- + SiO ₃ ^2- + F ^- + 0.6×alkalinity (as CaCO ₃ )] mg/L

(3) Electrical conductivity judgment step

Electrical neutrality can be obtained by Equation 5, and a series of calculation processes are required as follows.

[Equation 5]

G _o ⁺ = ∑(C ⁺ × λ ⁺ )

G _o ^- = ∑(C ^- × λ ^- )
Z ⁺ = (∑C ⁺ ×z ⁺² )/(∑C ⁺ ×z ⁺ )

Z ^- = (∑C ^- ×z ^-2 )/(∑C ^- ×z ^- )

delete

Λ ^o (total ionic conductance) = G _o ⁺ + G _o ^-

Λ ⁺ = G _o ⁺ /∑C _o ⁺

Λ ^- = G _o ^- /∑C _o ^-

Q = (Λ ^o × Z ^- × Z ⁺ )/{(Z ⁺ + Z ^- ) × (Z ⁺ ×Λ ^- + Z ^- × Λ ⁺ )}

C ^o = (∑C ⁺ + ∑C ^- )/2

Term1 = G _o ⁺ + G _o ^- = ∑(C ⁺ × λ ⁺ ) + ∑(C ^- × λ ^- )

Term2 = (Λ ^o × Z ^- × Z ⁺ )/{115.2 × (Z ^- + Z ⁺ )}

Term3 = (2 × Q) / (1+√Q)

Term4 = {(Z ^- + Z ⁺ ) × C ^o } ^1.5 = {(Z ^- + Z ⁺ ) × (∑C ⁺ +∑C ^- /2)} ^1.5

EC = Term1-(Term2 × Term3) + 0.668 × Term4

Electrical conductivity can be calculated using hypothetical values as shown in Table 3.

Table 3 relates to the electrical conductivity calculation template.

The symbols and formulas shown in Table 3 are summarized as follows.

C ^+(-) : Normality (N) concentration (Normality, mili-equivalent/L, meq/L)

z ^+(-) : Absolute value of ionic value

λ ^+(-) : Electrical conductivity of ions

Table 4 relates to the electrical conductivity of ions.

In order to calculate each parameter value in the above formula, you must first use experimental values or perform complex calculations as follows.

The normal (N) concentration of the solute (Normality, mili-equivalent/L, meq/L) can be calculated as follows.

N = {amount of solute (g/L)} / {g equivalent weight of solute (molecular weight/valence)}

Example) N concentration of Ca ⁺⁺ of 27.8 mg/L = 27.8 / (40/2) = 1.39 meq/L

However, the N concentration (meq/L) of CO ₃ ^2- , HCO ₃ , ^2- , and OH ^- ions, which are components of pH and alkalinity, is calculated through a very complicated process using the following equation.

- [H ⁺ ]=(10^-pH (measured value)×1000)/γ ₁ (γ ₁ : ionic strength correction value)

- [CO ₃ ^2- ] = (Ct × K1 × K2) / (Factor × 2 × 1000)

- [HCO ₃ ^- ] = (Ct × [H+] × K1) / Factor

- [OH ^- ] = (Kw / [H ⁺ ]) × 1000

Here, in order to calculate the N concentration (meq/L) of pH and alkalinity, the values of each parameter γ ₁ , Ct, K1, K2, Factor, and Kw must be calculated as follows.

1) γ ₁ (ion strength correction value)

T (absolute temperature, ^o K) = 273.15 + x ℃

E = 60954/[T + 116] - 68.937

A = 1.82 × 10 ⁶ × (E × T) ^-1.5

I (or μ) = TDS (measured value, mg/l) × 0.000025

From Log[γ ₁ ] = -A × 1 ² {√I/(1+√I) - 0.3 × I}, the value of γ ₁ is 10^(log[γ _z ]).

For example, in Table 5 below, Log[γ ₁ ] = -A × 1 ² {√I/(1+√I) - 0.3 × I}, so if the value of Log[γ ₁ ] is -0.039, γ ₁ = 10 ^(-0.039) = 0.913.

2) C _t or C _co2 = DIC (Dissolved Inorganic Carbon)

A) C _t is the mol concentration of CO ₂ and DIC represents the g concentration of CO ₂ as dissolved inorganic carbon. In water, it is expressed as mmol/L and mg/L, respectively.

B) To calculate C _t or C _{co2 &} DIC, the parameters must first be calculated as shown in Table 6 below.

c) K1, K2, Kw, H ⁺ calculation

To obtain the K1, K2, and Kw values, first obtain the pK( ^o K) value to correct the temperature as follows.

d) From the constant values generated during the dissociation reaction (experimental results, A1 to A5), pK( ^o K) (temperature coefficient), which corrects the correlation between temperature and equilibrium constant, must be obtained using the following equation.

pK = A1 + A2/T + A3×Log(T) + A4×T + A5/T^2

E) If the water temperature of the sample is 20.3 ^o C,

T( ^o K) = 273.15 (absolute temperature of 0 ^o C) + 20.3 ^o C = 293.45

f) Therefore, the constant values (A1~A5) and pK( ^o K) are calculated according to the above formula as shown in Table 7 below.

Table 7 relates to Temperature Coefficients for a Variety of Acid-Base and Solubility Constants.

G) Calculation of K1 and K2 from corrected pK

From temperature correction pK

- The value of K1, H ₂ CO ₃ = HCO ₃ ^- + H ⁺ the equilibrium constant of the reaction equation

- Calculate the equilibrium constant of the K2 value, HCO ₃ ^- = CO ₃ ^2- + H ⁺ reaction equation, as follows.

According to the literature, the equilibrium constant can generally be calculated using the following equation:

- K =[AHCO ₃ ^- ][AH ⁺ ]/[H ₂ CO ₃ ]

- K′=[HCO ₃ ][AH ⁺ ]/[H ₂ CO ³ ]

- K′=K/γ ₁

However, in actual water quality testing, carbonic acid (H ₂ CO ³ ) is not measured, making calculation difficult, so the equilibrium constant (K′) corrected from pK( ^o K) must be obtained as follows.

- K = 10^(-pK( ^o K))

- K′=K × (γ ₁ / γ ₂ )

-pK′=

Table 8 relates to the calculation of the corrected equilibrium constant (K′) from the temperature corrected pK.

Therefore, the corrected K1 and K2 are 4.56×10 ^-7 and 5.56×10 ^-7 , respectively.

H) Temperature correction Kw is the equilibrium constant of the H ₂ O = H ⁺ + OH ^- reaction equation, so it is 7.67 × 10 ^-15 in Table 8 above.

I) The value of H ⁺ is 10^(pH), so it can be calculated from the measured pH.

For example, if pH=8.1, H ⁺ = 10 ^-8.1 = 7.94 ^-9 .

j) Factor, Sigma, Delta calculation

- Factor = [H ⁺ ]^2 + [H ⁺ ] × K1 + K1 × K2

- Sigma = ([H ⁺ ] × K1 + 2K1 × K2) / Factor

- Delta = (Kw/[H ⁺ ]) - ([H ⁺ ]/γ ₁ )

H) Ct calculation

- Ct = (Alk (mg/L)/50000 - Delta)/Sigma

3) Calculation of electrical conductivity of ions

Once the calculation of N concentration (meq/L) of pH and alkalinity is completed as above, calculate EC according to the procedure and formula in the 'Electrical Conductivity Calculation Template'.

To put it all back together

It can be organized as:

4) Comparison of measured and calculated values of electrical conductivity

Since the electrical conductivity value calculated in the above is 544μS/cm and the measured value is 531μS/cm, the error is {(531-544)/531}×100 = -2.5%, which is within 3%, so the water quality analysis is judged to be good. I do it.

Since the above is only a description of some of the preferred embodiments that can be implemented by the present invention, as is well known, the scope of the present invention should not be construed as limited to the above embodiments, and the scope of the present invention described above Both the technical idea and the technical idea underlying it will be said to be included in the scope of the present invention.

Claims (4)

delete An error verification method for raw water quality analysis that compares measured values by water quality measurement and theoretically calculated values using the measured values to determine whether they match within the allowable error range,
An electrical neutrality determination step of determining whether the electrical neutrality of the measured value and the calculated value match within an error range;
A TDS determination step of determining whether the TDS (Total Dissolved Solid) of the measured value and the calculated value match within an error range;
It includes an electrical conductivity determination step of determining whether the electrical conductivity of the measured value and the calculated value match within the error range,
The electrical neutrality determination step is,
An error verification method for raw water quality analysis, characterized in that the calculated value is obtained using Equations 1 to 3.
[Equation 1]
TA≡2[CO ₃ ^2- ]+[HCO ₃ ^- ]+[H ₂ BO ₃ ^- ]+2[HBO ₃ ^2- ]+3[BO ₃ ^3- ]+[OH ^- ]+[organic/inorganic H ⁺ acceptors]-[H ⁺ ]
TA: Total Alkalinity
[organic/inorganic H ⁺ acceptors]: Organic and/or inorganic electron acceptors
[Equation 2]
[H ⁺ ]=2[CO ₃ ^2- ]+[HCO ₃ ^- ]+[H ₂ BO ₃ ^- ]+2[HBO ₃ ^2- ]+3[BO ₃ ^3- ]+[OH ^- ]+[organic /inorganic H ⁺ acceptors]
[Equation 3]
{(Total positive ions - Total negative ions)/(Total positive ions + Total negative ions)}×100 (%) = Electrical neutrality
An error verification method for raw water quality analysis that compares measured values by water quality measurement and theoretically calculated values using the measured values to determine whether they match within the allowable error range,
An electrical neutrality determination step of determining whether the electrical neutrality of the measured value and the calculated value match within an error range;
A TDS determination step of determining whether the TDS (Total Dissolved Solid) of the measured value and the calculated value match within an error range;
It includes an electrical conductivity determination step of determining whether the electrical conductivity of the measured value and the calculated value match within the error range,
The TDS determination step is,
An error verification method for raw water quality analysis, characterized in that the calculated value is obtained by Equation 4.
[Equation 4]
TDS, mg/L = [Na ⁺ + K ⁺ + Ca ²⁺ + Mg ²⁺ + Cl ^- + NO ₃ ^- + SiO ₃ ^2- + F ^- + 0.6×alkalinity (as CaCO ₃ )] mg/L
An error verification method for raw water quality analysis that compares measured values by water quality measurement and theoretically calculated values using the measured values to determine whether they match within the allowable error range,
An electrical neutrality determination step of determining whether the electrical neutrality of the measured value and the calculated value match within an error range;
A TDS determination step of determining whether the TDS (Total Dissolved Solid) of the measured value and the calculated value match within an error range;
It includes an electrical conductivity determination step of determining whether the electrical conductivity of the measured value and the calculated value match within the error range,
The electrical conductivity determination step is,
An error verification method for raw water quality analysis, characterized in that the calculated value is obtained by Equation 5.
[Equation 5]

G _o ⁺ = ∑(C ⁺ × λ ⁺ )
G _o ^- = ∑(C ^- × λ ^- )
Z ⁺ = (∑C ⁺ ×z ⁺² )/(∑C ⁺ ×z ⁺ )
Z ^- = (∑C ^- ×z ^-2 )/(∑C ^- ×z ^- )
Λ ^o (total ionic conductance) = G _o ⁺ + G _o ^-
Λ ⁺ = G _o ⁺ /∑ C _o ⁺
Λ ^- = G _o ^- /∑C _o ^-
Q = (Λ ^o × Z ^- × Z ⁺ )/{(Z ⁺ + Z ^- ) × (Z ⁺ ×Λ ^- + Z ^- × Λ ⁺ )}
C ^o = (∑C ⁺ + ∑C ^- )/2
Term1 = G _o ⁺ + G _o ^- = ∑(C ⁺ × λ ⁺ ) + ∑(C ^- × λ ^- )
Term2 = (Λ ^o × Z ^- × Z ⁺ )/{115.2 × (Z ^- + Z ⁺ )}
Term3 = (2 × Q) / (1+√Q)
Term4 = {(Z ^- + Z ⁺ ) × C ^o } ^1.5 = {(Z ^- + Z ⁺ ) × (∑C ⁺ +∑C ^- /2)} ^1.5
EC = Term1-(Term2 × Term3) + 0.668 × Term4
C ^+(-) : Normality (N) concentration (Normality, mili-equivalent/L, meq/L)
z ^+(-) : Absolute value of ionic value
λ ^+(-) : Electrical conductivity of ions
EC: Electrical Conductivity
C ⁺ : normal concentration of cation
C ^- : Normal concentration of anion
z ⁺ : Absolute value of cation ion value (absolute value of cation charge)
z ^- : Absolute value of anion ion value (absolute value of anion charge)
λ ⁺ : Electrical conductivity of cations
λ ^- : Electrical conductivity of anions