Water quality sampling bottle for high-altitude remote area and sampling method of water quality sampling bottle

Abstract

The invention discloses a water quality sampling bottle for a high-altitude remote area, the water quality sampling bottle is provided with a liquid release device and a sample mixing device, the liquid release device and the sampling bottle are rapidly and tightly installed and can quantitatively and slowly release a fixing agent, and the sample mixing device does not need external power supply; the fixing agent is prefabricated and contains components for fixing COD (Chemical Oxygen Demand) and ammonia nitrogen at the same time.

Description

Technical Field

[0001] This invention relates to the field of water sample monitoring technology, and in particular to the collection and long-distance transportation of water samples in remote high-altitude areas. Background Technology

[0002] Water quality in high-altitude, remote areas (such as the Qinghai-Tibet Plateau in my country and the high mountains of the western United States) is not only a core indicator of the regional ecological environment but also a crucial carrier for studying global climate change, glacial evolution, and geological weathering processes. However, these areas face numerous unique challenges in water quality sampling and preservation due to their high altitude, harsh climate, and inconvenient transportation. On the one hand, long-distance, long-duration, and bumpy transportation can easily lead to leakage, breakage, or sample deterioration of sampling bottles; the low air pressure and large diurnal temperature range in the high-altitude environment can easily cause ordinary bottles to deform under negative pressure or fail to seal. On the other hand, samples from high-altitude areas also face the problem of long transportation cycles; after water sample collection, ammonia nitrogen is prone to transformation due to microbial decomposition and chemical oxidation. Therefore, samples from high-altitude, remote areas often exceed the conventional preservation time limit from the collection point to the laboratory. Related studies have shown that water quality samples from high-altitude lakes in the western United States, under refrigeration, show no significant changes in various indicators within 48 hours; after 48 hours, pH and Na+... + NH4 + Six indicators showed statistically significant changes.

[0003] Currently, after sampling water quality in high-altitude and remote areas, fixatives (such as pH adjusters and preservatives) are generally added to ensure that the water sample composition remains unchanged. The fixatives required for different monitoring items (such as nutrients, heavy metals, organic matter, and cyanide) vary significantly. Traditional fixatives, such as sulfuric acid, are highly corrosive and their acidification is irreversible. Traditional fixatives are often used specifically for COD or ammonia nitrogen, requiring the addition of different fixatives in two separate steps, which is cumbersome and prone to interference with test results due to reagent interactions (e.g., potassium dichromate oxidizes ammonia nitrogen, leading to data distortion). Chloride ions and sulfides in the water can interfere with COD determination, while microbial activity can cause ammonia nitrogen to be converted into nitrates, affecting concentration accuracy. Furthermore, fixatives containing heavy metals such as mercury and chromium (such as mercuric sulfate) are prone to causing secondary pollution, resulting in high subsequent wastewater treatment costs.

[0004] Existing patents such as CN217766032U (a water quality sampling bottle) and CN204675027U (a quantitative mixing container) disclose sampling bottles that are unsuitable for high-altitude and remote areas. Specifically, the low air pressure and large temperature differences in high-altitude environments cause ordinary bottles to easily deform under negative pressure or fail to seal. While fixatives (such as pH adjusters and preservatives) are typically added after sampling to maintain the water sample composition, uneven release of the fixative and insufficient sample mixing affect the accuracy of the analytical results. These methods cannot achieve quantitative and slow release of the fixative and require additional external power, making it impossible to achieve complete mixing of the fixative with the water sample in a short time. Furthermore, they cannot simultaneously achieve synergistic fixation of COD and ammonia nitrogen. To shield interfering substances, additional scavenging agents and masking agents are required, making the process cumbersome. Therefore, these methods are not suitable for convenient and repeated use by sampling personnel in high-altitude and remote areas, and reagent interactions can easily affect the accuracy of the analytical results.

[0005] For ammonia nitrogen and COD, pure concentrated sulfuric acid is generally used as a fixative to avoid contamination of the water sample by impurities. This requires a considerable amount of equipment, including: acid burettes or pipettes, syringe wash bulbs, pH test paper or a portable pH meter, etc. During the procedure, concentrated sulfuric acid is drawn up using an acid burette or pipette and slowly added dropwise along the wall of the sampling bottle. The bottle must also be manually shaken to ensure thorough mixing of the sulfuric acid with the water sample. After adding acid, the sample should be allowed to stand for at least 5 minutes, and the pH value should be measured using pH test paper or a portable pH meter to ensure it meets the target requirements. If the pH does not meet the requirements, concentrated sulfuric acid should be added dropwise until the desired result is achieved.

[0006] The use of acid to fix ammonia nitrogen and COD has obvious drawbacks: (1) Concentrated sulfuric acid has extremely strong corrosive and dehydrating properties. If the operation is not handled properly during the acid addition process, it is easy to cause boiling and splashing, resulting in burns to the skin and mucous membranes. A large amount of heat is released during dilution. If the operation is carried out in a closed container, the container may burst due to increased pressure. The volatilization of acid mist can also irritate the respiratory tract. Long-term exposure may damage the respiratory mucosa. It is necessary to operate in a fume hood with professional protective equipment (acid-resistant gloves and goggles), which increases the operational threshold for on-site sampling. (2) Sulfuric acid is highly corrosive, which causes metal ions to dissolve and contaminate the water sample. After long-term use, the pistons and pipettes of instruments such as acid burettes and pipettes are easily corroded by acid, resulting in problems such as leakage and decreased accuracy. They need to be replaced regularly, which increases the consumption rate of experimental consumables. (3) Fixed acidic water samples (pH≤2) are corrosive hazardous materials. During transportation, they must comply with the regulations for the transportation of hazardous materials (such as using leak-proof refrigerated boxes and affixing hazardous material labels). The transportation cost is significantly higher than that of ordinary water samples. When storing, they must be stored separately on corrosion-resistant shelves to avoid mixing with alkaline reagents and flammable materials. It is also necessary to prevent the container from breaking and causing acid leakage, which could pollute the laboratory environment or damage other equipment. The sulfuric acid waste liquid after testing must be neutralized with sodium hydroxide and then discharged in accordance with the laboratory wastewater treatment regulations to avoid corroding pipes or polluting the environment. (4) Fixed single indicator is cumbersome. If multiple indicators need to be monitored simultaneously, water samples need to be sampled in separate bottles and different fixatives need to be added, which increases the workload of sampling, transportation and testing, and is prone to sample confusion. (5) The storage time is limited and cannot meet the needs of long-term monitoring. Even with sulfuric acid fixation and refrigeration at 4°C, the preservation time of most indicators is still relatively short, which cannot meet the long-term preservation requirements of scenarios such as long-distance sampling and large-scale monitoring (basic sampling round trip in high-altitude and remote areas takes 10-14 days). For water samples that need to be tracked for a long time (such as pollution source tracing monitoring), the stability of sulfuric acid fixation is insufficient, which may cause subsequent test data to lose its reference value. (5) It is not suitable for the needs of rapid on-site law enforcement or supervision and monitoring. Rapid on-site monitoring (such as supervision and law enforcement) requires fixatives to be easy to operate and without complex protection requirements, while the strong corrosiveness and operational complexity of sulfuric acid limit its application on-site.

[0007] Therefore, there is an urgent need to research and develop a new type of sampling bottle and a new sampling method that is suitable for remote high-altitude areas, can withstand extreme weather and air pressure fluctuations, is easy to operate on-site, can be mixed uniformly without power, can meet the stable requirements of COD and ammonia nitrogen sampling indicators with a single addition, and can be stored for a long time. Summary of the Invention

[0008] To address the aforementioned technical problems, this invention provides a water sampling bottle for high-altitude remote areas and a water sampling method for high-altitude remote areas.

[0009] The water quality sampling bottle for high-altitude remote areas provided by the present invention has a liquid release device and a sample mixing device. The liquid release device is quickly and tightly installed with the sampling bottle and can release a fixative in a quantitative and slow manner. The sample mixing device does not require external power. The fixative is pre-made and contains components that fix both COD and ammonia nitrogen.

[0010] In some possible embodiments, the fixative comprises, by weight parts, 10-18 parts modified potassium persulfate, 12-20 parts modified tea saponin, 5-8 parts citrate-sodium citrate buffer, 3-5 parts dibutyl phthalate, and 20-35 parts deionized water, wherein the modified tea saponin is obtained by modifying tea saponin with ethanolamine, and the modified potassium persulfate is potassium persulfate modified by hydroxylation. The modification method of potassium persulfate is as follows: potassium persulfate and ethanol are mixed at a mass ratio of 1:3-1:8, 0.2-2% sodium hydroxide catalyst is added, and the mixture is reacted at 30-70°C for 1-3 hours and then dried.

[0011] In some possible embodiments, the fixative also includes 8-12 parts of modified aluminosilicate, which is obtained by modifying aluminosilicate with ethanolamine.

[0012] In some possible implementations, the fixative also includes 3-6 parts of disodium ethylenediaminetetraacetate.

[0013] In some possible implementations, the sample mixing device is located at the bottom of the bottle and is fixedly connected to the bottle body, making it impact-resistant and preventing it from falling off. The sample mixing device can achieve uniform mixing of the sample and fixative by moving or shaking the sampling bottle, or by utilizing natural eddies, without the need for power.

[0014] Furthermore, the sample mixing device is a four-bladed 30° oblique spiral blade, with a blade thickness of 2 mm and a height of 30 mm.

[0015] In some possible implementations, the liquid dispensing device is threaded into the bottle body, allowing for quick insertion and installation.

[0016] In some possible implementations, the sampling bottle neck has a threaded interface and is equipped with a main and an auxiliary high-elasticity fluororubber and silicone O-rings, as well as an outer flexible silicone sealing ring, to ensure that it does not deform during long-term storage and transportation under low pressure conditions.

[0017] In one possible implementation, the liquid release device includes a metering chamber, a rotary graduated needle valve, an adjustable flow needle valve, a transparent viewing window, and a built-in damping system.

[0018] Furthermore, the volume of the metering chamber is 0.5-10ml, allowing for direct observation of the remaining dose.

[0019] Furthermore, the rotary graduated needle valve is equipped with a return spring, with a minimum adjustment of 0.1 ml.

[0020] Furthermore, the adjustable flow needle valve has an adjustment range of 0.1ml / min-1ml / min, supports manual or automatic knob operation, and the release speed fluctuation does not exceed 5% under negative pressure.

[0021] In some possible implementations, the liquid release device includes an antifreeze and anti-icing thickened valve core and a low-temperature lubricating component.

[0022] In some possible implementations, the bottle body is made of reinforced food-grade polypropylene (PP), with a capacity of 200-800ml, a thick-walled and slender design, and a threaded neck with a diameter of 30-60mm.

[0023] Furthermore, the bottle body is structurally reinforced, resistant to large temperature differences from -20℃ to 60℃ and pressure fluctuations from -400mbar to 2bar, static pressure resistance of 1MPa, dynamic drop resistance of >3m, and supports high-temperature sterilization.

[0024] The water sampling method for high-altitude and remote areas provided by this invention uses the aforementioned sampling bottle to collect water samples. A fixative is pre-placed in the liquid slow-release device of the sampling bottle. The water sample is directly collected into the sampling bottle, and the liquid release device is screwed tightly onto the bottle neck before transport, eliminating the need to open the bottle a second time. Utilizing natural bumps during transport, combined with a mixing device at the bottom of the bottle to generate a strong vortex, the sample and reagents are uniformly mixed. This method allows for room temperature storage or refrigerated storage at 0-4℃ during water sample transport.

[0025] In some possible implementations, the liquid release device is adjusted during transport to control the slow release of the required fixative into the water sample inside the bottle.

[0026] In some possible implementations, the collected water samples are surface water, domestic sewage, or industrial wastewater samples with COD concentrations of 50-5000 mg / L and ammonia nitrogen concentrations of 0.5-100 mg / L.

[0027] In some possible implementations, the fixative is added at a ratio of 1.5% to 2% of the water sample volume.

[0028] The fixative of this invention is a synergistic fixative comprising modified potassium persulfate, modified tea saponin, modified aluminosilicate, disodium EDTA, citrate-sodium citrate buffer, and dibutyl phthalate. Through a dual mechanism of "oxidative inhibition + complexation stabilization," it simultaneously fixes COD and ammonia nitrogen, satisfying the stability requirements of both indicators with a single addition. The fixative can also specifically shield common interfering substances in water, such as chloride ions and sulfides, while exhibiting low corrosivity. This fixative can effectively extend the preservation period of water samples.

[0029] This sampling bottle features a liquid slow-release device, allowing for the manual or automatic slow addition of pre-prepared fixative after sampling to simultaneously fix COD and ammonia nitrogen in the water sample. The liquid-releasing device at the bottom of the bottle enables uniform mixing of the sample and fixative without external power, achieved through moving and shaking the sampling bottle or utilizing natural eddies. This eliminates the need for sample transfer and processing, reducing operational complexity. Combined with the accompanying fixative, it effectively addresses the long-standing problem in monitoring where long transportation distances in high-altitude areas cause COD or ammonia nitrogen levels to exceed their shelf life, affecting the accuracy of analytical results.

[0030] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0031] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the water quality sampling bottle structure in a remote area at an altitude according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the liquid release device for water quality sampling bottles in remote areas at high altitudes, according to an embodiment of the present invention. Figure 3 This is a schematic diagram of the water quality sampling bottle sample mixing device in a remote area at an altitude according to an embodiment of the present invention.

[0032] 1 is the release head, 2 is the fixative metering chamber, 3 is the liquid outlet, 4 is the sealing module, 5 is the special anti-accidental touch safety button, and 6 is the one-piece injection molded four-blade spiral guide vane. Detailed Implementation

[0033] The embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. The embodiments of the present invention are described in detail below.

[0034] Example 1 Water sampling bottles in high-altitude and remote areas The sampling bottle consists of a bottle head and a bottle body, and its structure is as follows: Figure 1 As shown, the bottle body is made of reinforced food-grade polypropylene (PP) material, with a 500ml capacity and a slender, thickened shell, providing excellent impact resistance and resistance to low / negative pressure, ensuring that the bottle body does not deform under low pressure conditions; the bottle neck threaded interface has a diameter of 45mm for easy and quick connection. The bottle bottom is a non-powered liquid mixing device with an integrated injection-molded four-blade spiral guide vane structure. The bottle bottom and mixing components are reinforced PP integral parts, which are structurally stable and not afraid of falling off or deforming due to transportation vibration or temperature difference. The sampling bottle head is a liquid release device, employing a rotary needle valve and micro-metering chamber design. It supports automatic / manual operation and can accurately set and achieve quantitative and slow release rates of 0.1ml-1ml / min. The transparent window design allows observation of remaining reagents even in low-light outdoor conditions. An integrated damping system ensures a stable release rate and prevents over-release even during atmospheric pressure fluctuations at high altitudes.

[0035] Liquid release device such as Figure 2 As shown, from top to bottom: Flow control knob (top): Diameter larger than the bottle opening, with anti-slip herringbone embossed surface.

[0036] Release head: It contains a rotary metering needle valve, covered with a transparent graduated window, and the central protrusion is the quantitative sample dispensing nozzle (which can be slightly concave to prevent water accumulation). The upper part is connected to the knob through a shaft seal, and the lower part extends into the bottle.

[0037] Fixative metering chamber: Located between the knob and the main release body, the outer wall is surrounded by bright scales and has a semi-transparent window for direct observation of the remaining amount; a one-way valve runs through the chamber, and the injection direction is designed for external injection, with a needle valve controlling the direction of entry into the bottle; Sealing module: The release device has an O-ring around its perimeter that fits tightly against the bottle opening; Special anti-accidental activation safety button: A small unlocking component or spring anti-accidental activation mechanism is set on the side of the release channel, which needs to be rotated or pressed to activate.

[0038] Fixative formulation composition and preparation method (1) Formula composition This fixative is a water-soluble liquid formulation, and the proportions by mass are as follows. The components work synergistically to achieve stable fixation of COD and ammonia nitrogen, while also shielding interfering ions.

[0039] Table 1 Fixative Formulation The modification method for aluminosilicates and tea saponins is as follows: 1. Select the target aluminosilicates and tea saponins, prepare a suspension with a mass fraction of 5%~20% using deionized water, stir evenly, and then ultrasonically disperse for 10~30 min. 2. Place the prepared suspension in a freezing device, set the temperature to -10℃~-40℃, and freeze for 4~24 h. 3. Remove the frozen sample and thaw it naturally at room temperature (20~25℃) or in a water bath (25~40℃) for 2~8 h. 4. Repeat the freeze-thaw cycle according to the modification requirements, generally 3~10 times. 5. The suspension after the freeze-thaw cycle is further modified with ethanolamine, and after centrifugation and drying, modified tea saponins are finally formed. 6. The suspension after the freeze-thaw cycle is centrifuged and dried to obtain modified aluminosilicates.

[0040] (2) Preparation method Pretreatment: Modified potassium persulfate and modified tea saponin are ground to a particle size ≤100 mesh to improve dissolution efficiency.

[0041] Mixing and dissolving: Add citrate-sodium citrate buffer and disodium ethylenediaminetetraacetate sequentially to deionized water, heat to 40°C and stir (300 r / min) for 15 minutes until completely dissolved.

[0042] Core component addition: Keeping the temperature and rotation speed constant, first add modified potassium persulfate and dibutyl phthalate, and stir for 20 minutes; then add modified tea saponin and hydroxylamine sulfate. Depending on the water sample, add modified aluminosilicate / disodium EDTA as needed. Continue stirring for 30 minutes to form a homogeneous solution.

[0043] Conditioning and Finished Product: Cool to room temperature, filter to remove undissolved impurities, and obtain a pale yellow transparent liquid fixative. Seal and package.

[0044] 3. Experimental equipment and conditions (1) Verification basis and reference standards Determination of Ammonia Nitrogen in Water by Nessler's Reagent Spectrophotometric Method (HJ 535-2009); Determination of Chemical Oxygen Demand in Water by Potassium Dichromate Method (HJ 828-2017); Technical Guidelines for Water Quality Sampling (HJ 493-2009); Laboratory Quality Control Standard for Water Quality Monitoring (HJ 168-2020); Research and development data related to the target fixative (such as modification process, functional groups, and recommended application scope).

[0045] (2) Experimental instruments and reagents Instruments and equipment: UV-Vis spectrophotometer (accuracy ±0.001A); microwave digester or COD reflux device; portable pH meter (accuracy ±0.1); electronic balance (accuracy 0.001g); constant temperature water bath (temperature control accuracy ±1℃); refrigerator (temperature control 0-4℃); ultrasonic cleaner; the aforementioned sampling bottles; pipettes, volumetric flasks, stoppered colorimetric tubes, and other standard laboratory glassware.

[0046] Reagents and Materials: Fixative (components detailed in Table 1). Standard Stock Solutions: Ammonia nitrogen standard stock solution (1000 mg / L, nationally certified standard substance); COD standard stock solution (1000 mg / L, prepared with potassium hydrogen phthalate). Detection Reagents: Nessler's reagent, potassium sodium tartrate solution, zinc sulfate solution, sodium hydroxide solution, potassium dichromate standard solution, silver sulfate-sulfuric acid solution, ferrous ammonium sulfate standard solution, ferroin indicator, etc. (all prepared according to HJ standards). Water Sample Matrix: Conventional Surface Water: Local river / lake water samples (pH 6.5-8.5, turbidity ≤20 NTU, chloride ion concentration ≤100 mg / L). High-Salinity Samples: Add sodium chloride to the surface water sample to prepare a simulated high-salinity sample with a chloride ion concentration of 5000 mg / L. High suspended solids water sample: Add dried and ground sediment powder to a surface water sample to prepare a simulated high suspended solids water sample with a suspended solids concentration of 500 mg / L. Auxiliary reagents: concentrated sulfuric acid (analytical grade), sodium hydroxide (analytical grade), deionized water (conductivity ≤10 μS / cm).

[0047] (3) Parameter gradient design Dosage gradient (based on preliminary experimental results): Ammonia nitrogen water samples: 0.2 g / L, 0.5 g / L, 1.0 g / L, 2.0 g / L, 3.0 g / L; COD water samples: 0.5g / L, 1.0g / L, 2.0g / L, 3.0g / L, 5.0g / L.

[0048] pH gradient: Adjust the initial pH of the water sample to 4.0, 5.5, 7.0, 8.5, and 10.0 (using concentrated sulfuric acid or sodium hydroxide solution).

[0049] Mixing time gradient: After adding the fixative, stir and mix for 15 min, 30 min, 60 min, 90 min, and 120 min respectively.

[0050] Storage duration nodes: Analysis is performed after saving 0h (initial value), 1d, 3d, 7d, 14d, 21d, and 30d respectively.

[0051] 4. Experimental Procedure (1) Water sample preparation Take 5L of each of the three types of substrate water samples (conventional surface water, high salinity water, and high suspended solids water), add ammonia nitrogen standard stock solution and COD standard stock solution respectively, and prepare simulated water samples with target concentrations of 2.0 mg / L ammonia nitrogen and 100 mg / L COD. After stirring evenly, let stand for 30 minutes.

[0052] (2) Fixative treatment According to the parameter gradient, take 500 mL of simulated water sample into the pretreated sampling bottle and adjust the pH to the set value; Accurately weigh the target fixative, add it to the water sample, and place it on a magnetic stirrer to stir for the set time. After completion, seal the sampling bottles and store them in a 4℃ refrigerator or at room temperature (20-25℃), and record the start time of storage.

[0053] (3) Sample testing and data recording Take samples according to the set storage time intervals. Shake the water samples well before sampling (for water samples with high suspended solids, mix thoroughly and take the samples immediately). Ammonia nitrogen detection: Operate according to the standard procedure of HJ 535-2009, measure the absorbance and calculate the ammonia nitrogen concentration; COD detection: Operate according to the standard procedure of HJ 828-2017, and calculate the COD concentration after titration; Each sample was measured in triplicate, and raw data such as absorbance and titration volume were recorded. The average value and relative standard deviation (RSD) were calculated.

[0054] (4) Interference verification experiment Take blank water samples without added ammonia nitrogen and COD standards, add the target fixative according to the optimal parameters, and test the ammonia nitrogen and COD contents after treatment to verify whether the fixative itself introduces interference. Compare the detection process between the target fixative treatment group and the traditional control group to observe whether there are any interference phenomena such as abnormal color development, precipitation, or incomplete digestion.

[0055] 5. Gradient Experiment Results (1) Gradient Dosage Experiment Table 2 shows the results and analysis of ammonia nitrogen dosage gradients in the water samples (initial ammonia nitrogen concentration = 50 mg / L; pH = 7.0; contact time = 30 min; stored at room temperature). Table 3 shows the COD dosage gradient for water samples (initial COD concentration = 1000 mg / L; pH = 7.0; contact time = 30 min; stored at room temperature). (2) pH gradient experiment Dosage = 2.0 g / L; Contact time = 30 min; Store at room temperature Table 4 shows the pH gradient of ammonia nitrogen in the water sample (initial ammonia nitrogen concentration = 50 mg / L). Table 5 shows the pH gradient of COD in the water sample (initial COD concentration of the water sample = 1000 mg / L). (3) Contact time gradient experiment (dosage = 2.0 g / L; pH = 7.0; storage at room temperature) Table 6 shows the mixing time gradient of ammonia nitrogen in the water samples (initial ammonia nitrogen concentration in the water samples = 50 mg / L). Table 7 shows the COD mixing time gradient of water samples (initial COD concentration of water samples = 1000 mg / L). Analysis shows that: 1. Optimal dosage: 2.0 g / L for ammonia nitrogen and 3.0 g / L for COD. This dosage provides the longest stable effect (21 days), with concentration fluctuations ≤3%, and offers the best cost-effectiveness.

[0056] 2. Suitable pH range: The fixation effect is best when the initial pH of the water sample is 7.0 (neutral), and 8.5 is also acceptable. However, strong acidity (pH≤4.0) or strong alkalinity (pH≥10.0) will significantly reduce the stabilization time. In practical applications, the pH of the water sample needs to be adjusted to 6.5-7.5 to meet the current water quality requirements of the Qinghai-Tibet Plateau.

[0057] 3. Optimal mixing time: After adding the fixative, the mixing and contact time should be 60 minutes to ensure that the complexation reaction and oxidation inhibition reaction are carried out completely, and to further extend the stabilization time. Considering that this device does not require external mixing, the time from sampling to arrival at the laboratory for analysis is more than sufficient.

[0058] 4. Long-term preservation effect: Under optimal conditions (ammonia nitrogen dosage 2.0 g / L, COD dosage 3.0 g / L, pH=7.0, contact for 60 min), the ammonia nitrogen / COD concentration fluctuation is ≤3% within 21 days of storage at room temperature. Refrigeration (0-4℃) can further extend the preservation time to more than 30 days, fully meeting the actual preservation needs of water samples for linear engineering environmental monitoring in the Qinghai-Tibet Plateau region.

[0059] Comparative Example 2 The fixative dosage for ammonia nitrogen water samples was 2.0 g / L, and the fixative dosage for COD water samples was 3.0 g / L. The pH of the water samples was adjusted to 7.0. After adding the fixative, the samples were mixed and contacted for 60 min. The other conditions were the same as those in Example 1, except that no fixative was added in Example 2.

[0060] Comparative Example 3 The dosage of fixative for ammonia nitrogen water samples was 2.0 g / L, and the dosage of fixative for COD water samples was 3.0 g / L. The pH of the water samples was adjusted to 7.0. After adding the fixative, the samples were mixed and contacted for 60 minutes. The other conditions were the same as those in Example 1. The only difference was that in Example 3, the fixative was traditional concentrated sulfuric acid. After taking 500 mL of simulated water sample, concentrated sulfuric acid was slowly added dropwise along the bottle wall. After stirring evenly, the pH was measured with a pH meter and found to be ≤2. The samples were then sealed and stored under the same conditions.

[0061] Comparative Example 4 The dosage of fixative for ammonia nitrogen water samples was 2.0 g / L, and the dosage of fixative for COD water samples was 3.0 g / L. The pH of the water samples was adjusted to 7.0. After adding the fixative, the samples were mixed and contacted for 60 min. The other conditions were the same as those in Example 1. The only difference was that Example 4 used a sampling bottle with existing technology (patent number).

[0062] Comparative Example 5 The dosage of fixative for ammonia nitrogen water samples was 2.0 g / L, and the dosage of fixative for COD water samples was 3.0 g / L. The pH of the water samples was adjusted to 7.0. After adding the fixative, the samples were mixed and contacted for 60 min. The other conditions were the same as those in Example 1. The only difference was that Example 5 used a sampling bottle with existing technology (patent number).

[0063] Comparative Example 6 The dosage of fixative for ammonia nitrogen water samples was 2.0 g / L, and the dosage of fixative for COD water samples was 3.0 g / L. The pH of the water samples was adjusted to 7.0. After adding the fixative, the samples were mixed and contacted for 60 min. The other conditions were the same as those in Example 1. The only difference was that the bottom of the sampling bottle in Example 6 did not contain an integrally molded four-leaf spiral guide structure.

[0064] Table 8 shows the comparison of COD and ammonia nitrogen stabilization time between Example 1 and Comparative Examples 2-8. Among them: 1. The stabilization period is the "longest storage time with concentration fluctuation ≤3%". After exceeding this period, the concentration fluctuation is >3%, which does not meet the requirements for the accuracy of the test data; 2. All groups are based on the average results of three types of matrix water samples (conventional surface water, high salinity sample, and high suspended solids water sample); 3. The storage conditions are divided into "room temperature (20-25℃)" and "4℃ refrigeration", which is consistent with the experimental design; 4. Comparative ratios 7-8 are supplementary control groups of common traditional fixatives, which are consistent with the comparison of actual application scenarios.

[0065] The comparison shows that the stability of Example 1 is significantly better than all the comparative examples. The core reason is the synergistic fixation mechanism generated by the liquid release device of the sampling bottle, the targeted removal of the fixative components, and the uniform mixing effect of the liquid mixing device at the bottom of the sampling bottle. The advantages are particularly prominent in complex matrix water samples such as high pH, ​​high saline, and high suspended solids. Comparative Example 4 (without fixative) had the shortest stabilization time, verifying the necessity of fixative; Comparative Example 5 (traditional concentrated sulfuric acid) had problems such as more interference, greater pollution, or cumbersome operation, and its stabilization time was much shorter than that of Example 1. The structure of the sampling bottle affects the stability time: sampling bottles with slow release and mixing functions can improve the uniformity of mixing between the fixative and the water sample, making the reaction more complete, and the stability time is 10%-25% longer than that of ordinary sampling bottles without this structure; Refrigeration (4°C) can inhibit microbial activity. The stability time of all groups is longer than that of room temperature, but the extension of Example 1 is the largest, which shows that the fixative + sampling bottle has a stronger ability to resist environmental fluctuations.

[0066] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A water sampling bottle for high-altitude, remote areas, characterized in that, The sampling bottle has a liquid release device and a sample mixing device. The liquid release device can be quickly and tightly installed with the sampling bottle and can release the fixative in a quantitative and slow manner. The sample mixing device does not require external power. The fixative is a pre-prepared component that simultaneously fixes COD and ammonia nitrogen.

2. A water quality sampling bottle for high-altitude remote areas as described in claim 1, characterized in that, The fixative comprises, by mass, 10-18 parts of modified potassium persulfate, 12-20 parts of modified tea saponin, 5-8 parts of citric acid-sodium citrate buffer, 3-5 parts of dibutyl phthalate, and 20-35 parts of deionized water. The modified tea saponin is obtained by modifying tea saponin with ethanolamine.

3. A water quality sampling bottle for high-altitude remote areas as described in claim 1, characterized in that, The fixative further includes 8-12 parts of modified aluminosilicate and / or 3-6 parts of disodium ethylenediaminetetraacetate, wherein the modified aluminosilicate is obtained by modifying aluminosilicate with ethanolamine.

4. A water quality sampling bottle for high-altitude remote areas as described in claim 1, characterized in that, The sample mixing device is located at the bottom of the bottle and is fixedly connected to the bottle body, making it impact-resistant and preventing it from falling off.

5. A water quality sampling bottle for high-altitude remote areas as described in claim 1, characterized in that, The sampling bottle has a threaded neck and is equipped with a main and an auxiliary high-elasticity fluororubber and silicone O-rings, as well as an outer flexible silicone sealing ring.

6. A water quality sampling bottle for high-altitude remote areas as described in claim 1, characterized in that, The liquid release device includes a metering chamber, a rotary graduated needle valve, an adjustable flow needle valve, a transparent viewing window, and a built-in damping system.

7. A water quality sampling bottle for high-altitude remote areas as described in claim 6, characterized in that, The metering chamber has a volume of 0.5-10ml, and / or the rotary graduated needle valve is equipped with a return spring with a minimum adjustment of 0.1ml, and / or the adjustable flow needle valve has an adjustment range of 0.1ml / min-1ml / min.

8. A method for water quality sampling in remote high-altitude areas, comprising collecting water samples using the sampling bottle described in any one of claims 1 to 7, characterized in that, The fixative is placed in the liquid slow-release device of the sampling bottle in advance. The water sample is collected directly into the sampling bottle. After the liquid release device is screwed onto the neck of the bottle, it is transported directly.

9. A water quality sampling method for high-altitude remote areas as described in claim 8, characterized in that, During transportation, adjust the liquid release device to control the slow release of the required fixative into the water sample inside the bottle.

10. A water quality sampling method for high-altitude remote areas as described in claim 8, characterized in that, The collected water samples were surface water, domestic sewage, and industrial wastewater with COD concentrations of 50-5000 mg / L and ammonia nitrogen concentrations of 0.5-100 mg / L.

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