Method for rapid detection of metal ions contained in fracturing water

Abstract

The present application relates to the technical field of oilfield water detection, and is a rapid detection method for metal ions contained in fracturing water, which is performed according to the following steps: measuring total conductivity of a fracturing water sample at T1, T2 and T3 temperatures, continuously adding a precipitant NaOH to the fracturing water sample, and measuring turbidity value changes of the fracturing water; when the turbidity value is stable, a turbid fracturing water liquid is obtained, and a turbidity detection value NTU of the turbid fracturing water liquid is recorded 测 , and the amount of the precipitant NaOH, while measuring conductivity of the turbid fracturing water liquid at T1, T2 and T3 temperatures; according to a series of correlation equation groups, concentrations of Na + , K + , Ca 2+ , Mg 2+ and Ba 2+ in the fracturing water sample are obtained. The present application adopts a fitting correlation equation group and a step-by-step rapid detection method, and has the advantages of rapid detection, accuracy, low cost, environmental protection, non-toxicity, simple operation, wide application range and the like.

Description

Technical Field

[0001] The invention relates to the technical field of oilfield water detection, and is a method for quickly detecting metal ions contained in fracturing water. Background Art

[0002] Fracturing fluid is the working fluid used during the fracturing of oil and gas reservoirs. Its primary function is to transmit the high pressure generated by surface equipment into the formation, causing fractures and proppant transport along the fractures. It is a chemical system composed of various additives, one of the main components being water. With the expansion of oilfield volume transformation and the increasing workload of fracturing, fracturing water consumption has increased annually. To alleviate water shortages, oilfields currently rely on multiple water sources or recycled fracturing water. However, these approaches suffer from complex and variable water composition and poor water salinity. This can lead to low fluid swelling rates, excessive foaming during the fracturing process, and poor gel temperature and shear resistance, significantly impacting fracturing fluid formulation and performance. The metal ion concentration in fracturing water is a key factor affecting fracturing fluid performance. Therefore, rapid on-site measurement of metal ion concentration in fracturing water can provide timely insights into the water's properties, providing data support for technical personnel to adjust the fracturing fluid formulation process.

[0003] The metal ion types contained in the water used for oilfield fracturing have the following characteristics: monovalent metal ions are mainly Na + , may contain a small amount of K + ; Divalent metal ions are Ca 2+ and Mg 2+ As the main body, there may be a small amount of Ba 2+ The concentrations of other monovalent metal ions and divalent metal ions are low, and their impact on the actual production of the oil field can be ignored.

[0004] At present, on-site detection of metal ion concentrations in fracturing water mainly relies on manual sampling and laboratory testing. The disadvantages of manual sampling and testing are slow sampling and monitoring speed, long measurement intervals, low work efficiency, high labor intensity, low data accuracy, and inability to timely grasp changes in the quality of fracturing water and fracturing fluid properties. Laboratory testing can use precision instruments such as spectroscopy, chromatography, and conductivity methods for high-precision analysis, but its disadvantages are low timeliness and high testing costs. The monitoring of fracturing water quality at oilfield sites has the following two characteristics: one is the requirement for real-time, rapid, and timely feedback on changes in metal ion concentrations, and the other is relatively low accuracy requirements. Therefore, in view of these two characteristics, it is necessary to develop a process method that can be used to quickly detect metal ions in fracturing water at oilfield sites. Summary of the Invention

[0005] The present invention provides a method for rapid detection of metal ions contained in fracturing water, which overcomes the shortcomings of the above-mentioned existing technologies. It can effectively solve the problems of slow detection speed and long measurement interval of metal ion concentration contained in fracturing water, and the inability to timely grasp the changes in water quality of fracturing water and fracturing fluid properties.

[0006] The technical solution of the present invention is achieved by the following measures: A method for rapid detection of metal ions contained in fracturing water is carried out according to the following steps:

[0007] S1, establish conductivity and Na + and K + Concentration correlation equations, turbidity values ​​and Ca 2+ Mg 2+ and Ba 2+ Concentration-related equations and conductivity and Ca 2+ Mg 2+ and Ba 2+ Concentration-related equations;

[0008] S2, measure the total conductivity of the fracturing water sample at temperatures T1, T2 and T3, respectively, denoted as σ T ,σ' T and σ" T ;

[0009] S3, continuously add precipitant NaOH to the fracturing water sample of step S2, and measure the change of turbidity value of fracturing water. When the turbidity value is stable, obtain turbidity liquid of fracturing water, and record the turbidity detection value NTU of turbidity liquid of fracturing water. 测 and the dosage of precipitant NaOH, and the conductivity of the turbid fluid used for fracturing water at temperatures T1, T2, and T3 were measured simultaneously;

[0010] S4, according to the conductivity and Na + and K + The concentration correlation equations are used to calculate the Na content in the fracturing water sample. + and K + concentration;

[0011] S5, based on conductivity and Ca 2+ Mg 2+ and Ba 2+ The concentration correlation equations are used to calculate the Ca content in the fracturing water sample. 2+ Mg 2+ and Ba 2+ concentration;

[0012] S6, the Ca in the fracturing water sample obtained in step S5 is 2+ Mg 2+ and Ba 2+ The concentration of Ca is brought into the turbidity value and2+ Mg 2 + and Ba 2+ The concentration correlation equation group is used to obtain the total turbidity calculation value NTU of the fracturing water turbidity fluid. T , and the detection value NTU 测 By comparison, the Ca content in the fracturing water sample calculated in step S5 is determined. 2+ Mg 2+ and Ba 2+ The accuracy of the concentration.

[0013] The following are further optimizations and / or improvements to the above technical solutions:

[0014] The sampling volume of the above-mentioned fracturing water samples is 1L to 20L. The Na + The concentration range is 100.0 mg / L to 50000.0 mg / L, K + The concentration range of Ca is 100.0 mg / L to 5000.0 mg / L. 2+ and Mg 2+ The concentration range of Ba 2+ The concentration range of Na in fracturing water samples is 10 mg / L to 500.0 mg / L; + , K + , Ca 2+ Mg 2+ and Ba 2+ The content of each other metal cation is not higher than 50 mg / L, and the total content of other metal cations is not higher than 300 mg / L.

[0015] In the above step S1, the conductivity and Na + and K + The concentration correlation equation group is carried out according to the following steps: prepare a series of standard aqueous solutions of NaCl and KCl, measure the conductivity of the series of standard aqueous solutions of NaCl and KCl at temperatures T1, T2, and T3 using a conductivity meter, draw the concentration-conductivity curve of the standard aqueous solutions of NaCl and KCl at temperatures T1, T2, and T3, and fit to obtain the linear equation group 1. The expression of equation group 1 is as follows:

[0016] σ (N+) =k 1(N+) ×C (N+) Formula 1-1

[0017] σ' (N+) =k1' (N+) ×C (N+) Formula 1-2

[0018] σ" (N+)=k1" (N+) ×C (N+) Formula 1-3

[0019] In the formula, N+ represents Na + or K + , C (N+) Indicates Na + or K + The concentration of the aqueous solution is in mg / L; σ (N+) ,σ' (N+) and σ" (N+) Na + or K + The conductivity of the aqueous solution at T1, T2 and T3, in μs / cm; k 1(N+) 、k1' (N+) and k1" (N+) Na + or K + Conductivity coefficient at temperatures T1, T2, and T3, unitless.

[0020] In the above step S1, the turbidity value and Ca 2+ Mg 2+ and Ba 2+ The concentration correlation equation system is carried out according to the following steps: prepare a series of standard aqueous solutions of CaCl2, MgCl2 and BaCl2, add sufficient amount of precipitant NaOH to them respectively, measure the turbidity of the standard aqueous solutions of CaCl2, MgCl2 and BaCl2 after reaction with sufficient amount of precipitant at temperature T1, draw the curve of change of CaCl2, MgCl2 and BaCl2 concentration with turbidity respectively, and fit to obtain linear equation system 2. The expression of equation system 2 is as follows:

[0021] NTU (M2+) =A 1(M2+) ×C (M2+) Formula 2

[0022] Among them, M2+ is Ca 2+ Mg 2+ Or Ba 2+ ; C (M2+) Ca 2+ Mg 2+ Or Ba 2+ Concentration of aqueous solution, in mg / L; NTU (M2+) Ca 2+ Mg 2+ Or Ba 2+ The turbidity of the aqueous solution after reacting with the precipitant NaOH is measured in NTU; A 1(M2+) is the turbidity coefficient, unitless.

[0023] In step S1, the conductivity is correlated with the Ca 2+ , Mg 2+ and Ba 2+ concentrations by the following steps: measuring the conductivities of CaCl2, MgCl2and BaCl2series standard sample aqueous solutions at T1, T2and T3temperatures, plotting the conductivity variation curves with ion concentrations at T1, T2and T3temperatures, and fitting to obtain the linear equation group 3, the expression of which is as follows:

[0024] σ (M2+) =k 2(M2+) ×C (M2+) Formula 3-1

[0025] σ' (M2+) =k2' (M2+) ×C (M2+) Formula 3-2

[0026] σ" (M2+) =k2" (M2+) ×C (M2+) Formula 3-3

[0027] In the formula, M2+is Ca 2+ , Mg 2+ or Ba 2+ ; C (M2+) is the concentration of Ca 2+ , Mg 2+ or Ba 2+ aqueous solution, in mg / L; σ (M2+) , σ' (M2+) and σ" (M2+) are the conductivities of Ca 2+ , Mg 2+ or Ba 2+ aqueous solution at T1, T2and T3, in μs / cm; k 2(M2+) , k2' (M2+) and k2" (M2+) are the conductivity coefficients of Ca 2+ , Mg 2+ or Ba 2+ at T1, T2and T3, without unit.

[0028] The specific operation of step S4 is as follows: according to the conductivity and Na + and K + concentration correlation equation group, the amount of the precipitant NaOH is converted into the increased Na + concentration in the fracturing water turbidity liquid due to the addition of the precipitant NaOH, and the following equation group 4 is used to calculate the Na + and K +The concentration of , the expression of Equation 4 is as follows:

[0029] σ1=k 1(Na+) C 1(Na+) + k 1 (K+) C (K+) Formula 4-1

[0030] σ'1=k' 1(Na+) C 1(Na+) + k' 1(K+) C (K+) Formula 4-2

[0031] σ"1=k" 1(Na+) C 1(Na+) + k" 1(K+) C (K+) Formula 4-3

[0032] C (Na+)= C 1(Na+) - C 2(Na+) Formula 4-4

[0033] Where C 1(Na+) 、C 1(K+) are respectively the Na in the turbid liquid of fracturing water + and K + The concentration, C 2(Na+) The Na added to the turbid liquid of fracturing water due to the addition of precipitant NaOH + Concentration, C (Na+) is the Na in the fracturing water sample + The concentration of σ1, σ'1 and σ"1 are the conductivity of the turbid fluid for fracturing water at temperatures T1, T2 and T3, respectively. 1(Na+) 、k1' (Na+) and k1" (Na+) are Na in Equation 1 at temperatures T1, T2, and T3, respectively. + The conductivity coefficient, k 1(K+) 、k1' (K+) and k1" (K+) are K in Equation 1 at temperatures T1, T2, and T3, respectively. + The conductivity coefficient.

[0034] The specific operation of the above step S5 is: according to the conductivity and Na + and K + The concentration correlation equations, combined with the Na added by the precipitant NaOH + The concentration of Ca in the fracturing water sample was calculated by establishing the following equation group 5. 2+ Mg 2+ and Ba 2+ The concentration of , the expression of Equation 5 is:

[0035] σ2= Formula 5-1

[0036] σ'2= Formula 5-2

[0037] σ"2= Formula 5-3

[0038] σ2=σ T -σ1+k 1(Na+) C 2(Na+) Formula 5-4

[0039] σ'2=σ' T -σ'1+k' 1(Na+) C 2(Na+) Formula 5-5

[0040] σ"2=σ" T -σ"1+k" 1(Na+) C 2(Na+) Formula 5-6

[0041] Where σ2, σ'2 and σ"2 are the changes in the conductivity of the turbid fluid used for fracturing at temperatures T1, T2 and T3, respectively; C 2(Na+) is the Na added by adding precipitant NaOH + Concentration; C (M2+) is the Ca content in the fracturing water sample 2+ Mg 2+ Or Ba 2+ concentration; σ1, σ'1 and σ"1 are the electrical conductivity of the turbid fluid used for fracturing at temperatures T1, T2 and T3 respectively; k 1(Na+) 、k1' (Na+) and k1" (Na+) are Na in Equation 1 + The corresponding conductivity coefficient, k 2(M2+) 、k2' (M2+) and k2" (M2+) are Ca in Equation 3 2+ Mg 2+ Or Ba 2+ The conductivity coefficient.

[0042] In the above step S6, if |NTU T -NTU 测 |≤10.0, then the Ca content of the fracturing water sample calculated in step S5 is 2+ Mg 2+ and Ba 2+ The concentration is accurate, among which the total turbidity calculation value of the fracturing water turbidity liquid is NTU T According to formula 6,

[0043] NTU T = Formula 6

[0044] Where C (M2+) is the Ca content in fracturing water samples 2+ Mg 2+ Or Ba 2+ The concentration of A is in mg / L. 1(M2+) Ca 2+ Mg 2+ Or Ba 2+ The corresponding turbidity coefficient in Equation 2.

[0045] In the above step S3, while adding the precipitant NaOH to the fracturing water sample, the fracturing water sample is stirred at a stirring speed of 100 rpm to 1000 rpm and a stirring time of 1 min to 5 min.

[0046] The above temperatures T1, T2 and T3 are all between 0 and 90°C, T1<T 2＜ T3 and the intervals between T1 and T2, T2 and T3 are 10°C to 20°C.

[0047] The present invention adopts the method of fitting correlation equations and step-by-step rapid determination to accurately obtain the Na content in fracturing water. + , K + , Ca 2+ Mg 2+ and Ba 2+ Compared with traditional methods, this method has the advantages of fast and accurate detection, low cost, environmental protection and non-toxicity, simple operation and wide application range. DETAILED DESCRIPTION

[0048] The present invention is not limited to the following embodiments, and specific implementation methods can be determined based on the technical solutions of the present invention and actual conditions. Unless otherwise specified, the various chemical reagents and chemicals mentioned in the present invention are all chemical reagents and chemicals commonly known in the prior art; unless otherwise specified, the percentages in the present invention are all percentages by mass; unless otherwise specified, the solutions in the present invention are all aqueous solutions with water as the solvent, for example, hydrochloric acid solution is an aqueous hydrochloric acid solution; normal temperature and room temperature in the present invention generally refer to temperatures between 15°C and 25°C, and are generally defined as 25°C.

[0049] The present invention will be further described below in conjunction with the embodiments:

[0050] Example 1: The method for rapid detection of metal ions contained in fracturing water is carried out according to the following steps:

[0051] S1, establish conductivity and Na + and K+ Concentration correlation equation group, turbidity value and Ca 2+ , Mg 2+ and Ba 2+ Concentration correlation equation group and conductivity and Ca 2+ , Mg 2+ and Ba 2+ Concentration correlation equation group;

[0052] S2, measure the total conductivity of the fracturing water sample at T1, T2 and T3, respectively, and record them as σ T , σ' T and σ" T ;

[0053] S3, continuously add precipitant NaOH to the fracturing water sample of step S2, and measure the change of turbidity value of the fracturing water, when the turbidity value is stable, the fracturing water turbid liquid is obtained, and record the turbidity detection value NTU of the fracturing water turbid liquid 测 and the amount of precipitant NaOH, and simultaneously measure the conductivity of the fracturing water turbid liquid at T1, T2 and T3;

[0054] S4, according to the conductivity and Na + and K + Concentration correlation equation group, the concentration of Na + and K + in the fracturing water sample is calculated;

[0055] S5, according to the conductivity and Ca 2+ , Mg 2+ and Ba 2+ Concentration correlation equation group, the concentration of Ca 2+ , Mg 2+ and Ba 2+ in the fracturing water sample is calculated;

[0056] S6, the concentration of Ca 2+ , Mg 2+ and Ba 2+ in the fracturing water sample obtained in step S5 is brought into the turbidity value and Ca 2+ , Mg 2 + and Ba 2+ Concentration correlation equation group, and the total turbidity calculation value NTU T of the fracturing water turbid liquid is obtained, which is compared with the detection value NTU 测 , to judge the accuracy of the concentration of Ca 2+ , Mg 2+ and Ba 2+ in the fracturing water sample calculated in step S5.

[0057] Example 2: As an optimization of the above example, the sampling volume of the fracturing water sample is 1L to 20L, and the Na content in the fracturing water sample is + The concentration range is 100.0 mg / L to 50000.0 mg / L, K + The concentration range of Ca is 100.0 mg / L to 5000.0 mg / L. 2+ and Mg 2+ The concentration range of Ba 2+ The concentration range of Na in fracturing water samples is 10 mg / L to 500.0 mg / L; + , K + , Ca 2+ Mg 2+ and Ba 2+ The content of each other metal cation is not higher than 50 mg / L, and the total content of other metal cations is not higher than 300 mg / L.

[0058] Example 3: As an optimization of the above example, in step S1, establish the conductivity and Na + and K + The concentration correlation equation group is carried out according to the following steps: prepare a series of standard aqueous solutions of NaCl and KCl, measure the conductivity of the series of standard aqueous solutions of NaCl and KCl at temperatures T1, T2, and T3 using a conductivity meter, draw the concentration-conductivity curve of the standard aqueous solutions of NaCl and KCl at temperatures T1, T2, and T3, and fit to obtain the linear equation group 1. The expression of equation group 1 is as follows:

[0059] σ (N+) =k 1(N+) ×C (N+) Formula 1-1

[0060] σ' (N+) =k1' (N+) ×C (N+) Formula 1-2

[0061] σ" (N+) =k1" (N+) ×C (N+) Formula 1-3

[0062] In the formula, N+ represents Na + or K + , C (N+) Indicates Na + or K + The concentration of the aqueous solution is in mg / L; σ (N+) ,σ' (N+) and σ" (N+) Na + or K +The conductivity of the aqueous solution at T1, T2 and T3, in μs / cm; k 1(N+) 、k1' (N+) and k1" (N+) Na + or K + Conductivity coefficient at temperatures T1, T2, and T3, unitless.

[0063] Example 4: As an optimization of the above example, in step S1, establish the relationship between turbidity value and Ca 2+ Mg 2+ and Ba 2+ The concentration correlation equation system is carried out according to the following steps: prepare a series of standard aqueous solutions of CaCl2, MgCl2 and BaCl2, add sufficient amount of precipitant NaOH to them respectively, measure the turbidity of the standard aqueous solutions of CaCl2, MgCl2 and BaCl2 after reaction with sufficient amount of precipitant at temperature T1, draw the curve of change of CaCl2, MgCl2 and BaCl2 concentration with turbidity respectively, and fit to obtain linear equation system 2. The expression of equation system 2 is as follows:

[0064] NTU (M2+) =A 1(M2+) ×C (M2+) Formula 2

[0065] Among them, M2+ is Ca 2+ Mg 2+ Or Ba 2+ ; C (M2+) Ca 2+ Mg 2+ Or Ba 2+ Concentration of aqueous solution, in mg / L; NTU (M2+) Ca 2+ Mg 2+ Or Ba 2+ The turbidity of the aqueous solution after reacting with the precipitant NaOH is measured in NTU; A 1(M2+) is the turbidity coefficient, unitless.

[0066] Example 5: As an optimization of the above example, in step S1, establish the conductivity and Ca 2+ Mg 2+ and Ba 2+ The concentration correlation equation group is carried out in the following steps: the conductivity of the aqueous solutions of a series of standard samples of CaCl2, MgCl2 and BaCl2 at temperatures T1, T2 and T3 is measured, the curves of conductivity versus ion concentration at temperatures T1, T2 and T3 are plotted, and the linear equation group 3 is obtained by fitting. The expression of equation group 3 is as follows:

[0067] σ (M2+) =k2(M2+) ×C (M2+) Formula 3-1

[0068] σ' (M2+) =k2' (M2+) ×C (M2+) Formula 3-2

[0069] σ" (M2+) =k2" (M2+) ×C (M2+) Formula 3-3

[0070] Where M2+ is Ca 2+ Mg 2+ Or Ba 2+ ; C (M2+) Ca 2+ Mg 2+ Or Ba 2+ The concentration of the aqueous solution is in mg / L; σ (M2+) ,σ' (M2+) and σ" (M2+) Ca 2+ Mg 2+ Or Ba 2+ The conductivity of the aqueous solution at T1, T2 and T3, in μs / cm; k 2(M2+) 、k2' (M2+) and k2" (M2+) Ca 2+ Mg 2+ Or Ba 2+ Conductivity coefficient at temperatures T1, T2, and T3, unitless.

[0071] Example 6: As an optimization of the above embodiment, the specific operation of step S4 is: according to the conductivity and Na + and K + The concentration correlation equation group converts the amount of precipitant NaOH into the Na added to the turbid liquid for fracturing water. + The concentration of Na in the fracturing water sample was calculated by establishing the following equation group 4: + and K + The concentration of , the expression of Equation 4 is as follows:

[0072] σ1=k 1(Na+) C 1(Na+) + k 1 (K+) C (K+) Formula 4-1

[0073] σ'1=k' 1(Na+) C 1(Na+) + k' 1(K+) C (K+) Formula 4-2

[0074] σ"1=k" 1(Na+) C 1(Na+) + k" 1(K+) C (K+) Formula 4-3

[0075] C (Na+)= C 1(Na+) - C 2(Na+) Formula 4-4

[0076] wherein C 1(Na+) , C 1(K+) are the concentrations of Na + and K + in the fracturing fluid, C 2(Na+) is the concentration of Na + added to the fracturing fluid by the precipitant NaOH, C (Na+) is the concentration of Na + in the fracturing fluid sample, σ1, σ'1 and σ"1 are the conductivities of the fracturing fluid at T1, T2 and T3, respectively, k 1(Na+) , k1' (Na+) and k1" (Na+) are the conductivity coefficients of Na + in equation group 1 at T1, T2 and T3, respectively, k 1(K+) , k1' (K+) and k1" (K+) are the conductivity coefficients of K + in equation group 1 at T1, T2 and T3, respectively.

[0077] According to the physical and chemical properties of the precipitate, Ca 2+ , Mg 2+ and Ba 2+ in the fracturing fluid form a precipitate with extremely low conductivity, which can be ignored. In the actual production of fracturing fluid in oilfield sites, monovalent metal ions are mainly Na + , and a small amount of K + may be contained, while other monovalent metal ions can be ignored. Therefore, the concentrations of Na + and K + in the fracturing fluid sample can be calculated by equation group 5, i.e. C (Na+) and C (K+) (C 1(K+) is equivalent to the concentration C + of K (K+) in the fracturing fluid sample). The Na +The concentration can be calculated from the volume of the fracturing water sample and the amount of the precipitant NaOH, wherein the precipitant NaOH can be an aqueous sodium hydroxide solution with a concentration of 20 g / L to 40 g / L.

[0078] Example 7: As an optimization of the above embodiment, the specific operation of step S5 is: according to the conductivity and Na + and K + The concentration correlation equations, combined with the Na added by the precipitant NaOH + The concentration of Ca in the fracturing water sample was calculated by establishing the following equation group 5. 2+ Mg 2+ and Ba 2+ The concentration of , the expression of Equation 5 is:

[0079] σ2= Formula 5-1

[0080] σ'2= Formula 5-2

[0081] σ"2= Formula 5-3

[0082] σ2=σ T -σ1+k 1(Na+) C 2(Na+) Formula 5-4

[0083] σ'2=σ' T -σ'1+k' 1(Na+) C 2(Na+) Formula 5-5

[0084] σ"2=σ" T -σ"1+k" 1(Na+) C 2(Na+) Formula 5-6

[0085] Where σ2, σ'2 and σ"2 are the changes in the conductivity of the turbid fluid used for fracturing at temperatures T1, T2 and T3, respectively; C 2(Na+) is the Na added by adding precipitant NaOH + Concentration; C (M2+) is the Ca content in the fracturing water sample 2+ Mg 2+ Or Ba 2+ concentration; σ1, σ'1 and σ"1 are the electrical conductivity of the turbid fluid used for fracturing at temperatures T1, T2 and T3 respectively; k 1(Na+) 、k1' (Na+) and k1" (Na+) are Na in Equation 1 + The corresponding conductivity coefficient, k 2(M2+) 、k2' (M2+)and k2" (M2+) are Ca in Equation 3 2+ Mg 2+ Or Ba 2+ The conductivity coefficient.

[0086] The main divalent metal ions in oilfield fracturing water are Ca 2+ Mg 2+ Mainly, may contain a small amount of Ba 2+ , the content of other divalent metal ions is low, and the influence of other divalent metal ions can be ignored in actual production.

[0087] Example 8: As an optimization of the above example, in step S6, if |NTU T -NTU 测 |≤10.0, then the Ca content of the fracturing water sample calculated in step S5 is 2+ Mg 2+ and Ba 2+ The concentration is accurate, among which the total turbidity calculation value of the fracturing water turbidity liquid is NTU T According to formula 6,

[0088] NTU T = Formula 6

[0089] Where C (M2+) is the Ca content in fracturing water samples 2+ Mg 2+ Or Ba 2+ The concentration of A is in mg / L. 1(M2+) Ca 2+ Mg 2+ Or Ba 2+ The corresponding turbidity coefficient in Equation 2.

[0090] Example 9: As an optimization of the above example, in step S3, while adding the precipitant NaOH to the fracturing water sample, the fracturing water sample is stirred at a stirring speed of 100 rpm to 1000 rpm and a stirring time of 1 min to 5 min.

[0091] Example 10: As an optimization of the above example, the temperatures T1, T2 and T3 are all between 0 and 90°C, and T1 < T 2＜ T3 and the intervals between T1 and T2, T2 and T3 are 10°C to 20°C.

[0092] The present invention provides a process for rapid detection of metal ions contained in oil field on-site fracturing water, which is suitable for Na + , K + , Ca 2+ Mg 2+and Ba 2+ The determination of ion content in the fracturing water sample is mainly based on the relationship between metal ion concentration and conductivity. + , K + and divalent metal ions Ca 2+ Mg 2+ and Ba 2+ The contribution to the conductivity of fracturing water at different temperatures is studied. The principle that divalent metal ions can react chemically with precipitants to form precipitates, making the fracturing water turbid, is used to determine the precipitation endpoint of divalent metal ions by measuring turbidity. The principle that divalent metal ion precipitates are non-conductive is used to shield the contribution of divalent metal ions in fracturing water to conductivity. By establishing the change in conductivity of fracturing water before and after the formation of divalent metal ion precipitation, the conductivity of monovalent and divalent metal ions in fracturing water is determined. By establishing the correlation equation between the conductivity and concentration of monovalent and divalent metal ions in fracturing water, the concentration of monovalent metal ions Na is determined. + , K + , and divalent metal ions Ca 2+ Mg 2+ and Ba 2+ The specific content of Ca 2+ Mg 2+ and Ba 2+ The content is verified by turbidity method to verify the accuracy of the method. In the process of establishing the correlation equation group of the present invention, a wider range of ion concentration variation of fracturing water is selected to correlate with turbidity and conductivity. The advantage is that the established correlation simulation equation group can be applied to complex situations such as large fluctuation range of concentration of fracturing water components, and the operation steps and accuracy are not affected by changes in conditions. The rapid detection method provided by the present invention can be used for on-site rapid detection of fracturing water in oil fields, and it can also be expanded to other Na + , K + , Ca 2+ Mg 2+ and Ba 2+ Rapid detection of water bodies with the main focus on detection can include water bodies around oil fields, industrial wastewater, etc.

[0093] Example 11: Na in the fracturing water sample + , K + , Ca 2+ Mg 2+ 、Ba 2+ The content determination was carried out according to the following steps:

[0094] Preparation of Na + , K + , Ca 2+ Mg 2+ 、Ba 2+A series of standard aqueous solutions with contents of 10,000 mg / L, 600 mg / L, 500 mg / L, 500 mg / L, and 100 mg / L were prepared. At experimental temperatures T1, T2, and T3 of 25°C, 35°C, and 45°C, respectively, the coefficients in Equation Group 1 and Equation Group 3 were determined according to the steps in Example 1:

[0095] k 1 (Na+) 、k1' (Na+) and k1" (Na+) They are 2.01, 2.11 and 2.22 respectively;

[0096] k 1 (K+) 、k1' (K+) and k1" (K+) They are 1.90, 2.01 and 2.10 respectively;

[0097] k 2 (Ca2+) 、k2' (Ca2+) and k2" (Ca2+) 2.83, 3.00 and 3.16 respectively;

[0098] k 2 (Mg2+) 、k2' (Mg2+) and k2" (Mg2+) They are 3.16, 3.31 and 3.49 respectively;

[0099] k 2 (Ba2+) 、k2' (Ba2+) and k2" (Ba2+) They are 2.21, 2.32 and 2.39 respectively.

[0100] In equation group 2:

[0101] A 1(Ca2+) 、A 1(Mg2+) and A 1( Ba2+) 0.76, 0.72, and 0.39, respectively;

[0102] The σ1, σ'1 and σ"1 of the fracturing water sample were measured to be 24576μs / cm, 25703μs / cm and 26983μs / cm at 25℃, 35℃ and 45℃ respectively.

[0103] Continuously add precipitant NaOH to the fracturing water sample in step S2, stir evenly and measure the turbidity value change of the fracturing water. When the turbidity value is stable, obtain the fracturing water turbidity liquid and record the turbidity detection value NTU of the fracturing water turbidity liquid. 测 =733.6 and the amount of precipitant NaOH, and the σ of the turbid liquid for fracturing water at 25℃, 35℃ and 45℃ were measured. T ,σ' T and σ" TThey are 24555.1μs / cm, 25687.5μs / cm and 26887μs / cm respectively.

[0104] Substituting the above data into Equation 4 and Equation 5, we can get: Na + , K + , Ca 2+ Mg 2+ 、Ba 2+ The contents were 9972.6 mg / L, 617.5 mg / L, 506.1 mg / L, 502.7 mg / L and 132.5 mg / L respectively.

[0105] Ca 2+ Mg 2+ 、Ba 2+ Substitute the content into formula 6 to calculate NTU T =729.0,|NTU T -NTU 测 |=4.6, indicating that the measurement results are accurate.

[0106] Example 12: Na in the fracturing water sample + , K + , Ca 2+ Mg 2+ 、Ba 2+ The content determination was carried out according to the following steps:

[0107] Preparation of Na + , K + , Ca 2+ Mg 2+ 、Ba 2+ A series of standard aqueous solutions with contents of 20,000 mg / L, 1,200 mg / L, 1,000 mg / L, 1,000 mg / L, and 200 mg / L were prepared. At experimental temperatures T1, T2, and T3 of 25°C, 35°C, and 55°C, respectively, the coefficients in Equation Group 1 and Equation Group 3 were determined according to the steps in Example 1:

[0108] k 1 (Na+) 、k1' (Na+) and k1" (Na+) 2.02, 2.10 and 2.32 respectively;

[0109] k 1 (K+) 、k1' (K+) and k1" (K+) They are 1.91, 2.01 and 2.20 respectively;

[0110] k 2 (Ca2+) 、k2' (Ca2+) and k2" (Ca2+)2.83, 3.00 and 3.31 respectively;

[0111] k 2 (Mg2+) 、k2' (Mg2+) and k2" (Mg2+) They are 3.16, 3.31 and 3.63 respectively;

[0112] k 2 (Ba2+) 、k2' (Ba2+) and k2" (Ba2+) They are 2.21, 2.32 and 2.51 respectively.

[0113] In equation group 2:

[0114] A 1 (Ca 2+) 、A 1 (Mg2+) and A 1 (Ba2+) They are 0.76, 0.72 and 0.39 respectively.

[0115] The σ1, σ'1 and σ"1 of the fracturing water sample were measured at 25℃, 35℃ and 55℃ to be 49167μs / cm, 51511μs / cm and 56706μs / cm respectively.

[0116] Continuously add precipitant NaOH to the fracturing water sample in step S2, stir evenly and measure the turbidity value change of the fracturing water. When the turbidity value is stable, obtain the fracturing water turbidity liquid and record the turbidity detection value NTU of the fracturing water turbidity liquid. 测 =1449.3 and the amount of precipitant NaOH, and the σ of the turbid liquid for fracturing water at 25℃, 35℃ and 55℃ was measured. T ,σ' T and σ" T They are 49063.5μs / cm, 51388.2μs / cm and 56516.6μs / cm respectively.

[0117] Substituting the above data into Equation 4 and Equation 5, we can get: Na + , K + , Ca 2+ Mg 2+ 、Ba 2+ The contents were 19872.1 mg / L, 1225.7 mg / L, 1018.6 mg / L, 1025.2 mg / L and 216.8 mg / L respectively.

[0118] Ca 2+ Mg 2+ 、Ba 2+ Substitute the content into formula 6 to calculate NTU T =1458.0,|NTU T -NTU 测|=8.7, indicating that the measurement results are accurate.

[0119] Example 13: Na in the fracturing water sample + , K + , Ca 2+ Mg 2+ 、Ba 2+ The content determination was carried out according to the following steps:

[0120] Preparation of Na + , K + , Ca 2+ Mg 2+ 、Ba 2+ A series of standard aqueous solutions with contents of 5000 mg / L, 300 mg / L, 250 mg / L, 250 mg / L, and 50 mg / L are prepared. At experimental temperatures T1, T2, and T3 of 25°C, 45°C, and 55°C, respectively, the coefficients in Equation Group 1 and Equation Group 3 are determined according to the steps in Example 1:

[0121] k 1 (Na+) 、k1' (Na+) and k1" (Na+) 2.03, 2.23 and 2.34 respectively;

[0122] k 1 (K+) 、k1' (K+) and k1" (K+) They are 1.90, 2.10 and 2.21 respectively;

[0123] k 2 (Ca2+) 、k2' (Ca2+) and k2" (Ca2+) 2.83, 3.16 and 3.31 respectively;

[0124] k 2 (Mg2+) 、k2' (Mg2+) and k2" (Mg2+) They are 3.16, 3.49 and 3.63 respectively;

[0125] k 2 (Ba2+) 、k2' (Ba2+) and k2" (Ba2+) They are 2.21, 2.39 and 2.51 respectively.

[0126] In equation group 2:

[0127] A 1(Ca2+) 、A 1(Mg2+) and A 1(Ba2+) They are 0.76, 0.72 and 0.39 respectively.

[0128] The σ1, σ'1 and σ"1 of the fracturing water sample were measured to be 12283μs / cm, 13465μs / cm and 14138μs / cm at 25℃, 45℃ and 55℃ respectively.

[0129] Continuously add precipitant NaOH to the fracturing water sample in step S2, stir evenly and measure the turbidity value change of the fracturing water. When the turbidity value is stable, obtain the fracturing water turbidity liquid and record the turbidity detection value NTU of the fracturing water turbidity liquid. 测 =367.3 and the amount of precipitant NaOH, and the σ of the turbid liquid for fracturing water at 225℃, 45℃ and 55℃ was measured. T ,σ' T and σ" T They are 12216μs / cm, 13295μs / cm and 14056μs / cm respectively.

[0130] Substituting the above data into Equation 4 and Equation 5, we can get: Na + , K + , Ca 2+ Mg 2+ 、Ba 2+ The contents were 4982.7 mg / L, 300.6 mg / L, 258.1 mg / L, 253.8.2 mg / L and 39.6 mg / L respectively.

[0131] Ca 2+ Mg 2+ 、Ba 2+ Substitute the content into formula 6 to calculate NTU T =364.5,|NTU T -NTU 测 |=2.8, indicating that the measurement results are accurate.

[0132] In summary, the present invention provides a process for rapid detection of metal ions contained in oil field on-site fracturing water, which is suitable for Na + , K + , Ca 2+ Mg 2+ and Ba 2+ This method measures the ion content of primary fracturing water samples. This method is fast, accurate, and low-cost, and does not use any environmentally harmful chemicals. The turbidity measurement requires minimal precipitant, and the resulting precipitate is a naturally occurring solid, non-toxic, and easy to handle. The conductivity meter measurement process consumes only minimal electrical energy. The process described in this invention offers rapid detection and accurate data, providing valuable support for on-site fracturing fluid configuration.

[0133] The above technical features constitute the embodiments of the present invention, which have strong adaptability and implementation effect. Non-essential technical features can be added or removed according to actual needs to meet the requirements of different situations.

Claims

1. A method for rapid detection of metal ions contained in fracturing water, characterized in that Follow these steps: S1, establish conductivity and Na + and K + Concentration correlation equations, turbidity values ​​and Ca 2+ Mg 2+ and Ba 2+ Concentration-related equations and conductivity and Ca 2+ Mg 2+ and Ba 2+ Concentration-related equations; S2, measuring the total conductivity of the fracturing water sample at temperatures T1, T2, and T3; S3, continuously add precipitant NaOH to the fracturing water sample of step S2, and measure the change of turbidity value of fracturing water. When the turbidity value is stable, obtain turbidity liquid of fracturing water, and record the turbidity detection value NTU of turbidity liquid of fracturing water. 测 and the dosage of precipitant NaOH, and the conductivity of the turbid fluid used for fracturing water at temperatures T1, T2, and T3 were measured simultaneously; S4, according to the conductivity and Na + and K + The concentration correlation equations are used to calculate the Na content in the fracturing water sample. + and K + concentration; S5, based on conductivity and Ca 2+ Mg 2+ and Ba 2+ The concentration correlation equations are used to calculate the Ca content in the fracturing water sample. 2+ Mg 2+ and Ba 2+ concentration; S6, the Ca in the fracturing water sample obtained in step S5 is 2+ Mg 2+ and Ba 2+ The concentration of Ca is brought into the turbidity value and 2+ Mg 2+ and Ba 2+ The concentration correlation equation group is used to obtain the total turbidity calculation value NTU of the fracturing water turbidity fluid. T , and the detection value NTU 测 By comparison, the Ca content in the fracturing water sample calculated in step S5 is determined. 2+ Mg 2+ and Ba 2+ The accuracy of the concentration.

2. The method for rapid detection of metal ions contained in fracturing water according to claim 1, characterized in that The sampling volume of fracturing water samples is 1L to 20L. The Na + The concentration range is 100.0 mg / L to 50000.0 mg / L, K + The concentration range of Ca is 100.0 mg / L to 5000.0 mg / L. 2+ and Mg 2+ The concentration range of Ba 2+ The concentration range of Na in fracturing water samples is 10 mg / L to 500.0 mg / L; + , K + , Ca 2+ Mg 2+ and Ba 2+ The content of each other metal cation is not higher than 50 mg / L, and the total content of other metal cations is not higher than 300 mg / L.

3. The method for rapid detection of metal ions contained in fracturing water according to claim 1 or 2, characterized in that In step S1, establish the conductivity and Na + and K + The concentration correlation equation group is carried out according to the following steps: prepare a series of standard aqueous solutions of NaCl and KCl, measure the conductivity of the series of standard aqueous solutions of NaCl and KCl at temperatures T1, T2, and T3 using a conductivity meter, draw the concentration-conductivity curve of the standard aqueous solutions of NaCl and KCl at temperatures T1, T2, and T3, and fit to obtain the linear equation group 1. The expression of equation group 1 is as follows: σ (N+) =k 1(N+) ×C (N+) Formula 1-1 in (N+) =k1' (N+) ×C (N+) formula 1-2 in (N+) =k1" (N+) ×C (N+) formula 1-3 In the formula, N+ represents Na + or K + , C (N+) Indicates Na + or K + The concentration of the aqueous solution is in mg / L; σ (N+) ,σ' (N+) and σ" (N+) Na + or K + The conductivity of the aqueous solution at T1, T2 and T3, in μs / cm; k 1(N+) 、k1' (N+) and k1" (N+) Na + or K + Conductivity coefficient at temperatures T1, T2, and T3, unitless.

4. The method for rapid detection of metal ions contained in fracturing water according to claim 1 or 2, characterized in that In step S1, establish the turbidity value and Ca 2+ Mg 2+ and Ba 2+ The concentration correlation equation system is carried out according to the following steps: prepare a series of standard aqueous solutions of CaCl2, MgCl2 and BaCl2, add sufficient amount of precipitant NaOH to them respectively, measure the turbidity of the standard aqueous solutions of CaCl2, MgCl2 and BaCl2 after reaction with sufficient amount of precipitant at temperature T1, draw the curve of change of CaCl2, MgCl2 and BaCl2 concentration with turbidity respectively, and fit to obtain linear equation system 2. The expression of equation system 2 is as follows: NTU (M2+) =A 1(M2+) ×C (M2+) Equation 2 Among them, M2+ is Ca 2+ Mg 2+ Or Ba 2+ ; C (M2+) Ca 2+ Mg 2+ Or Ba 2+ Concentration of aqueous solution, in mg / L; NTU (M2+) Ca 2+ Mg 2+ Or Ba 2+ The turbidity of the aqueous solution after reacting with the precipitant NaOH is measured in NTU; A 1(M2+) is the turbidity coefficient, unitless.

5. The method for rapid detection of metal ions contained in fracturing water according to claim 3, characterized in that In step S1, establish the turbidity value and Ca 2+ Mg 2+ and Ba 2+ The concentration correlation equation system is carried out according to the following steps: prepare a series of standard aqueous solutions of CaCl2, MgCl2 and BaCl2, add sufficient amount of precipitant NaOH to them respectively, measure the turbidity of the standard aqueous solutions of CaCl2, MgCl2 and BaCl2 after reaction with sufficient amount of precipitant at temperature T1, draw the curve of change of CaCl2, MgCl2 and BaCl2 concentration with turbidity respectively, and fit to obtain linear equation system 2. The expression of equation system 2 is as follows: NTU (M2+) = A 1(M2+) × C (M2+) Equation 2 Among them, M2+ is Ca 2+ Mg 2+ Or Ba 2+ ; C (M2+) Ca 2+ Mg 2+ Or Ba 2+ Concentration of aqueous solution, in mg / L; NTU (M2+) Ca 2+ Mg 2+ Or Ba 2+ The turbidity of the aqueous solution after reacting with the precipitant NaOH is measured in NTU; A 1(M2+) is the turbidity coefficient, unitless.

6. The method for rapid detection of metal ions contained in fracturing water according to claim 1, 2 or 5, characterized in that In step S1, establish the conductivity and Ca 2+ Mg 2+ and Ba 2+ The concentration correlation equation group is carried out in the following steps: the conductivity of the aqueous solutions of a series of standard samples of CaCl2, MgCl2 and BaCl2 at temperatures T1, T2 and T3 is measured, the curves of conductivity versus ion concentration at temperatures T1, T2 and T3 are plotted, and the linear equation group 3 is obtained by fitting. The expression of equation group 3 is as follows: σ (M2+) =k 2(M2+) ×C (M2+) Formula 3-1 σ' (M2+) =k2' (M2+) ×C (M2+) Formula 3-2 σ" (M2+) =k2" (M2+) ×C (M2+) Formula 3-3 Where M2+ is Ca 2+ Mg 2+ Or Ba 2+ ; C (M2+) Ca 2+ Mg 2+ Or Ba 2+ The concentration of the aqueous solution is in mg / L; σ (M2+) ,σ' (M2+) and σ" (M2+) Ca 2+ Mg 2+ Or Ba 2+ The conductivity of the aqueous solution at T1, T2 and T3, in μs / cm; k 2(M2+) 、k2' (M2+) and k2" (M2+) Ca 2+ Mg 2+ Or Ba 2+ Conductivity coefficient at temperatures T1, T2, and T3, unitless.

7. The method for rapid detection of metal ions contained in fracturing water according to claim 3, characterized in that In step S1, establish the conductivity and Ca 2+ Mg 2+ and Ba 2+ The concentration correlation equation group is carried out in the following steps: the conductivity of the aqueous solutions of a series of standard samples of CaCl2, MgCl2 and BaCl2 at temperatures T1, T2 and T3 is measured, the curves of conductivity versus ion concentration at temperatures T1, T2 and T3 are plotted, and the linear equation group 3 is obtained by fitting. The expression of equation group 3 is as follows: σ (M2+) =k 2(M2+) ×C (M2+) Formula 3-1 σ' (M2+) =k2' (M2+) ×C (M2+) Formula 3-2 σ" (M2+) =k2" (M2+) ×C (M2+) Formula 3-3 Where M2+ is Ca 2+ Mg 2+ Or Ba 2+ ; C (M2+) Ca 2+ Mg 2+ Or Ba 2+ The concentration of the aqueous solution is in mg / L; σ (M2+) ,σ' (M2+) and σ" (M2+) Ca 2+ Mg 2+ Or Ba 2+ The conductivity of the aqueous solution at T1, T2 and T3, in μs / cm; k 2(M2+) 、k2' (M2+) and k2" (M2+) Ca 2+ Mg 2+ Or Ba 2+ Conductivity coefficient at temperatures T1, T2, and T3, unitless.

8. The method for rapid detection of metal ions contained in fracturing water according to claim 4, characterized in that In step S1, establish the conductivity and Ca 2+ Mg 2+ and Ba 2+ The concentration correlation equation group is carried out in the following steps: the conductivity of the aqueous solutions of a series of standard samples of CaCl2, MgCl2 and BaCl2 at temperatures T1, T2 and T3 is measured, the curves of conductivity versus ion concentration at temperatures T1, T2 and T3 are plotted, and the linear equation group 3 is obtained by fitting. The expression of equation group 3 is as follows: σ (M2+) =k 2(M2+) ×C (M2+) Formula 3-1 σ' (M2+) =k2' (M2+) ×C (M2+) Formula 3-2 σ" (M2+) =k2" (M2+) ×C (M2+) Formula 3-3 Where M2+ is Ca 2+ Mg 2+ Or Ba 2+ ; C (M2+) Ca 2+ Mg 2+ Or Ba 2+ The concentration of the aqueous solution is in mg / L; σ (M2+) ,σ' (M2+) and σ" (M2+) Ca 2+ Mg 2+ Or Ba 2+ The conductivity of the aqueous solution at T1, T2 and T3, in μs / cm; k 2(M2+) 、k2' (M2+) and k2" (M2+) Ca 2+ Mg 2+ Or Ba 2+ Conductivity coefficient at temperatures T1, T2, and T3, unitless.

9. The method for rapid detection of metal ions contained in fracturing water according to claim 5, characterized in that The specific operation of step S4 is: according to the conductivity and Na + and K + The concentration correlation equation group converts the amount of precipitant NaOH into the Na added to the turbid liquid for fracturing water. + The concentration of Na in the fracturing water sample was calculated by establishing the following equation group 4: + and K + The concentration of , the expression of Equation 4 is as follows: σ1=k 1(Na+) C 1(Na+) + k 1 (K+) C (K+) Formula 4-1 σ'1=k' 1(Na+) C 1(Na+) + k' 1(K+) C (K+) Formula 4-2 σ"1=k" 1(Na+) C 1(Na+) + k" 1(K+) C (K+) Formula 4-3 C (Na+)= C 1(Na+) - C 2(Na+) Formula 4-4 Where C 1(Na+) 、C 1(K+) are respectively the Na in the turbid liquid of fracturing water + and K + The concentration, C 2(Na+) The Na added to the turbid liquid of fracturing water due to the addition of precipitant NaOH + Concentration, C (Na+) is the Na in the fracturing water sample + The concentration of σ1, σ'1 and σ"1 are the conductivity of the turbid fluid for fracturing water at temperatures T1, T2 and T3, respectively. 1(Na+) 、k1' (Na+) and k1" (Na+) are Na in Equation 1 at temperatures T1, T2, and T3, respectively. + The conductivity coefficient, k 1(K+) 、k1' (K+) and k1" (K+) are K in Equation 1 at temperatures T1, T2, and T3, respectively. + The conductivity coefficient.

10. The method for rapid detection of metal ions contained in fracturing water according to claim 9, characterized in that The specific operation of step S5 is: according to the conductivity and Na + and K + The concentration correlation equations, combined with the Na added by the precipitant NaOH + The concentration of Ca in the fracturing water sample was calculated by establishing the following equation group 5. 2+ Mg 2+ and Ba 2+ The concentration of , the expression of Equation 5 is: σ2=σ T -σ1+k 1(Na+) C 2(Na+) formula 5-4 σ'2=σ' T -σ'1+k' 1(Na+) C 2(Na+) formula 5-5 σ"2=σ" T -σ"1+k" 1(Na+) C 2(Na+) formula 5-6 Where σ2, σ'2 and σ"2 are the changes in the conductivity of the turbid fluid used for fracturing at temperatures T1, T2 and T3, respectively; C 2(Na+) is the Na added by adding precipitant NaOH + Concentration; C (M2+) is the Ca content in the fracturing water sample 2+ Mg 2+ Or Ba 2+ concentration; σ1, σ'1 and σ"1 are the electrical conductivity of the turbid fluid used for fracturing at temperatures T1, T2 and T3 respectively; k 1(Na+) 、k1' (Na+) and k1" (Na+) are Na in Equation 1 + The corresponding conductivity coefficient, k 2(M2+) 、k2' (M2+) and k2" (M2+) are Ca in Equation 3 2+ Mg 2+ Or Ba 2+ The conductivity coefficient.

11. The method for rapid detection of metal ions contained in fracturing water according to claim 10, characterized in that In step S6, if |NTU T -NTU 测 |≤10.0, then the Ca content of the fracturing water sample calculated in step S5 is 2+ Mg 2+ and Ba 2+ The concentration is accurate, among which the total turbidity calculation value of the fracturing water turbidity liquid is NTU T According to formula 6, Where C (M2+) is the Ca content in fracturing water samples 2+ Mg 2+ Or Ba 2+ The concentration of A is in mg / L. 1(M2+) Ca 2+ Mg 2+ Or Ba 2+ The corresponding turbidity coefficient in Equation 2.

12. The method for rapid detection of metal ions contained in fracturing water according to claim 7, 8, 9, 10 or 11, characterized in that In step S3, while adding the precipitant NaOH to the fracturing water sample, the fracturing water sample is stirred at a stirring speed of 100 rpm to 1000 rpm and a stirring time of 1 min to 5 min.

13. The method for rapid detection of metal ions contained in fracturing water according to claim 1 or 2, characterized in that Temperatures T1, T2 and T3 are all between 0 and 90°C, T1<T 2＜ T3 and the intervals between T1 and T2, T2 and T3 are 10°C to 20°C.

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