A water quality detection method for fire-fighting drainage of an electrochemical energy storage power station

Abstract

This invention discloses a water quality testing method for fire drainage from electrochemical energy storage power stations, belonging to the field of fire protection and environmental protection technology. The method includes: simulating battery combustion and fire extinguishing under various operating conditions through experiments; collecting water samples from the fire drainage after fire extinguishing and testing them to obtain water quality data for the fire drainage under various operating conditions; comparing the water quality data with engineering design parameters to obtain the water quality testing results for the fire drainage from the electrochemical energy storage power station. This method overcomes the difficulties in sampling fire drainage at fire sites of lithium battery electrochemical energy storage power stations and the atypicality of collected samples. By using water quality parameters, the destination of fire drainage can be determined based on different site conditions, thereby promoting the large-scale application of lithium battery energy storage power stations.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of water quality detection method of fire-fighting drainage of electrochemical energy storage power station, belong to fire-fighting environmental protection technical field. BACKGROUND

[0002] Lithium battery energy storage power station is generally composed of a certain number of energy storage battery cabins, which are generally built using standard containers. Hundreds of lithium iron phosphate battery modules are arranged in the container, each battery module is composed of dozens of single batteries, and up to about 10,000 single batteries can be placed in one energy storage battery cabin. Under the conditions of overcharge, overload and other conditions, chemical reactions will occur inside the battery, resulting in continuous heat generation and thermal runaway, and then fire.

[0003] Current studies show that water-based extinguishing agents are more effective. When fire-fighting water is used to extinguish lithium battery energy storage power station fires, a large amount of fire-fighting wastewater will be discharged. Lithium batteries are composed of electrolyte lithium salt, electrolyte and other components, which are complex. At present, there is a lack of research on the quality of fire-fighting drainage water. In actual engineering, there is controversy about the outlet of fire-fighting drainage. On the one hand, fire-fighting drainage is a kind of emergency state drainage, and its drainage can be discharged or discharged through the station drainage system as long as it does not affect the normal operation of fire-fighting equipment. On the other hand, the energy density of energy storage power station is large, and up to about 10,000 single batteries are arranged in one energy storage battery cabin. Once the fire gets out of control, the single batteries will undergo a chain thermal runaway reaction and catch fire, generating a large amount of fire-fighting drainage. Some documents show that the electrolyte of lithium battery contains toxic and harmful substances, and is prone to secondary pollution in the natural environment. If the electrolyte enters the environment, it can undergo hydrolysis, decomposition and combustion chemical reaction products, producing fluorine-containing, arsenic-containing and phosphorus-containing compounds. If such harmful substances are randomly discharged into the environment, they may cause pollution to water sources and soil that cannot or is difficult to degrade, causing greater ecological environmental hazards. Some people believe that lithium batteries achieve charging and discharging functions through electrochemical effects, and are biased towards chemical projects in terms of equipment composition and characteristics. Polluted fire-fighting water should be effectively collected and discharged, and an emergency water pool should be set up to store wastewater containing pollutants, including fire-fighting wastewater.

[0004] The best way to solve the controversy over the outlet of fire-fighting drainage in engineering construction is to collect fire-fighting drainage samples at the fire scene and detect their composition, and then make a comprehensive judgment on the destination of fire-fighting drainage based on the results. However, this method has the following problems: (1) Sampling at the fire scene is difficult. On the one hand, the occurrence of fire is occasional, and the detection unit cannot arrive in time. On the other hand, the fire scene is in an emergency management state, and it is not suitable for non-rescue personnel to approach the fire scene. (2) Because the use of batteries is different, the capacity of the batteries is different, and the time of fire development (fire duration) is different, the quality of the drainage is also different, so a single water sample detection cannot reflect the whole picture, that is, the water sample may not be typical. SUMMARY

[0005] The present application aims to provide a water quality detection method for fire-fighting drainage of an electrochemical energy storage power station, which can overcome the problems of difficulty in sampling and untypicality of collected samples of fire-fighting drainage at a lithium battery electrochemical energy storage power station fire site, determine the destination of fire-fighting drainage based on different station site conditions through water quality parameters, and further promote the large-scale application of lithium battery energy storage power stations.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0007] A water quality detection method for fire-fighting drainage of an electrochemical energy storage power station, comprising:

[0008] Simulating the combustion and extinguishing of the battery under various working conditions through experiments;

[0009] Collecting the water sample of the fire-fighting drainage after extinguishing and detecting it to obtain the water quality data of the fire-fighting drainage of the battery under various working conditions;

[0010] Comparing the water quality data with the engineering design parameters to obtain the water quality detection result of the fire-fighting drainage of the electrochemical energy storage power station.

[0011] Further, the working conditions include battery fires of different usage degrees, battery fires of different SOC states, battery fires of different combustion times, and any combination of the three kinds of battery fires.

[0012] Further, the step of simulating the combustion and extinguishing of the battery under various working conditions through experiments comprises:

[0013] Taking single batteries as experimental objects, marking unused batteries as Group A batteries and marking used batteries as Group B batteries;

[0014] Using a charge-discharge tester, charging or discharging the Group A batteries and the Group B batteries to each SOC state at the same preset current;

[0015] Causing thermal runaway of the Group A batteries and the Group B batteries at each SOC state until combustion;

[0016] Extinguishing the combusting Group A batteries and Group B batteries;

[0017] The Group A batteries and the Group B batteries each include original batteries and dissected batteries.

[0018] The method for causing thermal runaway of the original batteries of the Group A batteries and the Group B batteries at each SOC state until combustion comprises overcharging and heating by an iron plate testing device.

[0019] The method for causing thermal runaway of the dissected batteries of the Group A batteries and the Group B batteries at each SOC state until combustion comprises artificial ignition.

[0020] Further, the collected fire-fighting drainage water sample after fire extinguishing is detected, including:

[0021] The collected fire-fighting drainage water sample after fire extinguishing is detected by using a glass electrode method.

[0022] The collected fire-fighting drainage water sample after fire extinguishing is detected by using an atomic absorption spectrophotometry method.

[0023] The collected fire-fighting drainage water sample after fire extinguishing is detected by using a dichromate method.

[0024] The collected fire-fighting drainage water sample after fire extinguishing is detected by using a weight method.

[0025] The collected fire-fighting drainage water sample after fire extinguishing is detected by using an ammonium molybdate spectrophotometry method.

[0026] The collected fire-fighting drainage water sample after fire extinguishing is detected by using a gas-phase molecular absorption method.

[0027] Further, the water quality data is compared with engineering design parameters to obtain a water quality detection result of fire-fighting drainage of the electrochemical energy storage power station, including:

[0028] The water quality detection result is corrected according to a preset amount of fire-fighting water to obtain a corrected water quality detection result.

[0029] An engineering design suggestion scheme is obtained according to the corrected water quality detection result.

[0030] Further, the battery is a lithium battery.

[0031] Compared with the prior art, the present application has the following beneficial effects:

[0032] The water quality detection method of fire-fighting drainage of the electrochemical energy storage power station provided by the present application overcomes the problems of difficulty in collecting fire-fighting drainage samples at a fire scene of the electrochemical energy storage power station and non-typicality of the collected samples, and the water quality of the fire-fighting drainage of the electrochemical energy storage power station obtained by the method can help solve the disputes existing in actual engineering, thereby promoting large-scale application of the electrochemical energy storage power station. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 is a flow chart of the water quality detection method of fire-fighting drainage of the electrochemical energy storage power station provided by the embodiment of the present application;

[0034] Figure 2 is a schematic diagram of a prefabricated energy storage cabin provided by the embodiment of the present application, wherein (a) is a battery module, and (b) is a prefabricated cabin.

[0035] Figure 3 is a schematic diagram of the relationship between the burning time and the different SOC states and the use degree of the battery provided by the embodiment of the application;

[0036] Figure 4 is a schematic diagram of the relationship between the fire-fighting water and the different SOC states and the use degree of the battery provided by the embodiment of the application;

[0037] Figure 5 is a schematic diagram of the change of the pH value of the battery fire-fighting drainage of the battery of different SOC states and the use degree of the battery provided by the embodiment of the application;

[0038] Figure 6 is a schematic diagram of the change of the heavy metal concentration of the battery fire-fighting drainage of the battery of different SOC states and the use degree of the battery provided by the embodiment of the application, wherein, -A represents a non-used battery pack, and -B represents a used battery pack;

[0039] Figure 7 is a schematic diagram of the distribution of the arsenic concentration of the battery fire-fighting drainage of the battery provided by the embodiment of the application after filtration;

[0040] Figure 8 is a schematic diagram of the distribution of the fluorine concentration of the battery fire-fighting drainage of the battery provided by the embodiment of the application after filtration;

[0041] Figure 9 is a schematic diagram of the concentration of the suspended matter of the battery fire-fighting drainage of the battery of different SOC states and the use degree of the battery provided by the embodiment of the application;

[0042] Figure 10 is a schematic diagram of the COD value of the battery fire-fighting drainage of the battery of different SOC states and the use degree of the battery provided by the embodiment of the application;

[0043] Figure 11 is a schematic diagram of the total phosphorus value of the battery fire-fighting drainage of the battery provided by the embodiment of the application after filtration. DETAILED DESCRIPTION

[0044] The technical solutions of the present application will be further described in detail below with reference to the specific embodiments.

[0045] The embodiments of the present application will be described in detail below, and examples of the embodiments are shown in the drawings, wherein the same or similar reference signs represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are only used to explain the present application, and cannot be understood as a limitation on the present application. The technical features in the embodiments of the present application and the embodiments can be combined with each other without conflict.

[0046] Embodiment 1:

[0047] Figure 1is a flow chart of a water quality detection method for fire-fighting drainage of an electrochemical energy storage power station provided in the embodiment. The flow chart only shows the logical order of the method of the embodiment, and the steps shown or described can be completed in an order different from that shown on the premise that they do not conflict with each other. Figure 1

[0048] Referring to Figure 1 , the method of the embodiment specifically includes the following steps:

[0049] Step one: simulate the combustion and extinguishing of the battery under various working conditions through experiments;

[0050] In the embodiment, the working conditions include battery fires of different use degrees, battery fires of different SOC states, battery fires of different combustion times, and any combination of the three kinds of battery fires.

[0051] Simulating the combustion and extinguishing of the battery under various working conditions through experiments includes the following steps:

[0052] Step A: using single batteries as experimental objects, marking unused batteries as Group A batteries and marking used batteries as Group B batteries;

[0053] Step B: using a charge-discharge tester, charging or discharging the Group A batteries and the Group B batteries to each SOC state at the same preset current;

[0054] Step C: causing the Group A batteries and the Group B batteries at each SOC state to thermal runaway until combustion;

[0055] In the embodiment, the Group A batteries and the Group B batteries each include original batteries and dissected batteries; the method of causing the original batteries of the Group A batteries and the Group B batteries at each SOC state to thermal runaway until combustion includes overcharging and heating by an iron plate test device; and the method of causing the dissected batteries of the Group A batteries and the Group B batteries at each SOC state to thermal runaway until combustion includes artificial ignition.

[0056] Step D: extinguishing the Group A batteries and the Group B batteries that are on fire.

[0057] Step two: collecting water samples of the fire-fighting drainage after extinguishing and detecting the water samples to obtain water quality data of the fire-fighting drainage of the battery under various working conditions;

[0058] Detecting the collected water samples of the fire-fighting drainage after extinguishing includes the following steps:

[0059] Step ①: using a glass electrode method, detecting the pH value of the collected water samples of the fire-fighting drainage after extinguishing;

[0060] Step ②: using an atomic absorption spectrophotometry method, detecting the heavy metal content of the collected water samples of the fire-fighting drainage after extinguishing; ​

[0061] Step ③: The collected fire-fighting drainage water sample after extinguishing is detected for chemical oxygen demand by using the dichromate method;

[0062] Step ④: The collected fire-fighting drainage water sample after extinguishing is detected for suspended solids content by using the weight method;

[0063] Step ⑤: The collected fire-fighting drainage water sample after extinguishing is detected for total phosphorus by using the ammonium molybdate spectrophotometric method;

[0064] Step ⑥: The collected fire-fighting drainage water sample after extinguishing is detected for ammonia nitrogen and total nitrogen by using the gas-phase molecular absorption method.

[0065] Step three: The water quality data are compared with the engineering design parameters to obtain the water quality detection results of the fire-fighting drainage of the electrochemical energy storage power station.

[0066] Comparing the water quality data with the engineering design parameters to obtain the water quality detection results of the fire-fighting drainage of the electrochemical energy storage power station includes the following steps:

[0067] Step I: The water quality detection results are corrected according to a preset amount of fire-fighting water to obtain corrected water quality detection results;

[0068] Step II: An engineering design proposal is obtained according to the corrected water quality detection results.

[0069] In this embodiment, the battery is a lithium battery.

[0070] As shown in Figure 2 The lithium battery energy storage power station is generally composed of a certain number of energy storage battery cabins, the energy storage battery cabin is generally built using a standard container, and hundreds of lithium iron phosphate battery modules are arranged in the container, each battery module is composed of dozens of single batteries, and about 10,000 single batteries can be placed in one energy storage battery cabin. Under the conditions of overcharge, overload, etc., chemical reactions occur in the battery, which continuously generates heat and leads to thermal runaway, and then a fire occurs.

[0071] The experimental object used in this embodiment is a lithium iron phosphate battery energy storage power station. Lithium iron phosphate battery is a type of lithium battery.

[0072] In actual application scenarios, lithium iron phosphate batteries have multiple working states including full load and empty load. For batteries working under different conditions, the internal energy is different, and the external combustion characteristics may be very different. Correspondingly, the indicators of the obtained fire-fighting drainage may also differ. Therefore, this embodiment uses lithium iron phosphate batteries in different states (including different state of charge (SOC) and different usage) as experimental objects to collect different fire-fighting drainage for storage detection.

[0073] This embodiment selects LP11025265-100Ah lithium iron phosphate battery as the experimental object, and selects the unused battery and the battery with 80% of the original state after multiple cycles. The battery parameters are shown in Table 1. The unused battery is marked as group A battery, and the used battery is marked as group B battery. The fully charged group A battery and group B battery are divided into three groups, which are A-1, A-2, A-3 and B-1, B-2, B-3 respectively. A-2, A-3 and B-2, B-3 batteries are discharged to 50% SOC and 0% SOC state respectively, as shown in Table 2.

[0074] The cycle charging and discharging uses the American Arbin battery fast charging and discharging equipment, model LBT5V200A.

[0075] This embodiment uses a stainless steel container to hold the lithium iron phosphate battery for fire experiment. The wall surface of the stainless steel container hardly has physical or chemical reaction with the substances in the fire-fighting drainage after the lithium iron phosphate battery burns.

[0076] Table 1 Basic parameters of experimental battery

[0077]

[0078] This embodiment uses artificial external fire source to ignite and burn, and about 500ml of water is added after about 10s-15s, at which time the flame burns more and more fiercely, and then water is continuously added until the battery is completely extinguished. The large block of material that cannot be burned is taken out, the water sample is collected, and the collected water sample is marked as A-1, A-2, A-3, B-1, B-2, B-3 according to the initial battery usage and SOC state, and sent for testing.

[0079] Table 2 Burning time and water consumption

[0080]

[0081] In Table 2, the burning time refers to the time from the start of the battery burning to the complete extinguishing of the fire.

[0082] The experiment found that: (1) the battery with 100% SOC state burns for a longer time and needs more water to extinguish the fire. The possible reason is that during the charging process of the lithium iron phosphate battery, lithium ions enter the electrolyte from the surface of the lithium iron phosphate crystal under the action of the electric field force, pass through the diaphragm, and then migrate to the surface of the graphite crystal. The more the battery capacity, the more Li embedded in the graphite crystal, and the more active the nature, which is more likely to cause reaction with air.

[0083] (2) Under the same SOC condition, the used battery has a longer burning time and a more intense burning degree, which may be due to the oxidation and corrosion of the battery during use, causing the battery material to become flammable. See Figure 3 .

[0084] (3) For the same group of batteries (used battery group or unused battery group), the amount of fire-fighting water is positively correlated with the burning time. See Figure 4 .

[0085] Collect water samples from the fire-fighting drainage of lithium iron phosphate batteries after extinguishing and test them. The test indicators include pH value, heavy metals (copper, zinc, nickel, cadmium, lead, manganese, etc.), arsenic, fluoride, chemical oxygen demand, suspended solids, total phosphorus, total nitrogen, and ammonia nitrogen. The detection methods include but are not limited to glass electrode method, atomic absorption spectrophotometry, dichromate method, gravimetric method, ammonium molybdate spectrophotometry, and gas-phase molecular absorption method.

[0086] The amount of fire-fighting drainage produced by battery burning experiments under different usage levels and different charging states is not the same. In order to compare the concentrations of various indicators, the water quality results are corrected based on the standard of 15L of fire-fighting water.

[0087] The pH value of the fire-fighting drainage of lithium iron phosphate batteries with different usage levels and different charging states does not change much, basically maintaining between 7.40 and 7.65, and it can be basically considered as a neutral liquid. Whether it is an unused battery or a used battery, the pH of the fire-fighting drainage after burning reaches a maximum at 50% SOC, which may be due to certain chemical substances produced by the battery burning at 50% SOC. Figure 5 The pH value of the fire-fighting drainage of batteries with different SOC states and battery usage levels is shown in the figure.

[0088] Figure 6 The heavy metal concentration of the fire-fighting drainage of batteries with different SOC states and battery usage levels is shown in the figure.

[0089] The detection of heavy metals in the solution found that the main heavy metal elements contained in the solution are copper, nickel, chromium, lead, and manganese.

[0090] Among the heavy metal elements contained in the fire-fighting drainage of lithium iron phosphate batteries, the content of copper and chromium is relatively high, and the content of other elements is relatively low. The content of manganese and lead is basically 0 (10 -4The content of copper and nickel in the un-used battery group first decreased and then increased with the increase of the battery capacity, and reached the bottom at 50% SOC. The content of copper and nickel in the used battery group first increased and then decreased with the increase of the battery capacity, and reached the maximum at 50% SOC. Unlike copper and nickel, the distribution of chromium element in the un-used battery group and the used battery group was similar, and reached the minimum at 50%. The concentration of lead and manganese element was very low, and could be regarded as trace amount, and the distribution trend could be basically ignored.

[0091] The battery industry pollutant emission standard stipulates that the drainage of the battery industry needs to keep the heavy metals within a certain range, and the specific requirements are: nickel Ni 1.0 mg / L; lead Pb 0.7 mg / L; manganese Mn 2.0 mg / L. The test results in the embodiment are all less than the stipulated values.

[0092] The content of arsenic element in the industrial drainage needs to be strictly controlled. Arsenic and arsenic compounds can enter the human body through water, air and food, etc., causing harm, and arsenic is extremely harmful to aquatic organisms. The water quality test shows that: Figure 7 In the A group battery, the content of arsenic in the battery fire-fighting drainage showed a downward trend with the decrease of the battery capacity, and the discharge amount at 50% SOC and 0% SOC was not much different, while in the B group battery, the opposite trend was shown. The opposite trends shown by the A group battery and the B group battery may be related to the use degree.

[0093] According to the total arsenic emission standard of the battery industry wastewater, the discharge concentration of arsenic should not exceed 0.5 mg / L, and the concentration of As in the fire-fighting drainage of the lithium iron phosphate battery before and after correction in this test did not exceed the standard. In the A group battery, the content of arsenic in the battery fire-fighting drainage showed a downward trend with the decrease of the battery capacity, and the discharge amount at 50% SOC and 0% SOC was not much different, while in the B group battery, the opposite trend was shown. The opposite trends shown by the A group battery and the B group battery may be related to the use degree.

[0094] Referring to Figure 8 , the content of fluorine in the fire-fighting drainage of the A group battery showed a downward trend with the increase of the battery SOC, and the value fluctuated greatly, among which a weak decrease occurred from 100% SOC to 50% SOC. The content of fluorine in the fire-fighting drainage of the B group battery showed an upward trend with the decrease of the battery SOC, and the value was maintained at about 150-200 mg / L.

[0095] The F content in the battery fire-fighting drainage has a weak variation with the SOC state of the battery, but the F content in the fire-fighting drainage of the unused battery is less than that of the used battery, which is greatly related to the use of the battery. The F content in the fire-fighting drainage of the used battery is greater than that of the unused battery, and the value of the used battery group is maintained at about 150-200 mg / L. According to the standard for battery industry wastewater discharge in the battery industry pollutant emission standard, the F content limit value is below 10.0 mg / L, and the F in the fire-fighting drainage of the lithium iron phosphate battery exceeds this standard value.

[0096] Figure 9 The suspended solids concentration diagram of the battery fire-fighting drainage for different SOC states and battery use degrees.

[0097] The suspended solids concentration in the fire-fighting wastewater of the lithium iron phosphate battery is mostly between 1.0-2.0 g / L, and the suspended solids concentration is high, and the suspended solids concentration in the battery fire-fighting drainage under different SOC states has little difference.

[0098] Figure 10 The COD value diagram of the battery fire-fighting drainage for different SOC states and battery use degrees.

[0099] Overall, the COD value of the fire-fighting drainage of the lithium iron phosphate battery under different states and use degrees is basically between 30-60 g / L. The main reason for the high COD value of the fire-fighting drainage is that the battery is not fully burned during combustion, and after using the fire-fighting water to extinguish the fire, a large amount of incompletely burned substances will flow out from the inside of the battery under the driving of the fire-fighting water.

[0100] Figure 11 The total phosphorus value diagram of the battery fire-fighting drainage after filtration.

[0101] In the lithium iron phosphate battery fire-fighting drainage experiment, the total phosphorus concentration is high, and the minimum is more than 100 mg / L. The main reason is that the electrode material of the lithium iron phosphate battery contains a large amount of lithium iron phosphate, which is easy to flow out with water during the battery combustion process. The influence of high temperature causes a series of chemical reactions of the electrode material in the fire-fighting drainage, resulting in a high total phosphorus concentration in the fire-fighting drainage.

[0102] The fire frequency of the energy storage power station is once; the standard for fire-fighting water outside the energy storage battery cabin is not less than 20 L / s, and the fire duration time is not less than 3 h; the action time of the fixed automatic fire extinguishing system (fine water mist) in the cabin is not less than 1 h.

[0103] Due to the limitation of the battery cabin equipment arrangement feature, the full water column of the fire extinguishing lance cannot directly act on the single battery in the module to extinguish the open fire and continue cooling. Therefore, outdoor fire-fighting water is used for cooling the outer wall of the energy storage battery cabin (including the burning cabin and the adjacent cabin) to achieve the purpose of fire control and prevent fire spread. Therefore, the outdoor fire-fighting water basically does not come into direct contact with the lithium iron phosphate battery to generate corresponding wastewater.

[0104] The current fixed automatic fire extinguishing system in the lithium iron phosphate energy storage battery cabin that has been experimentally verified to have fire extinguishing efficiency mainly refers to the water mist fire extinguishing system and the perfluorohexone gas fire extinguishing system. Taking an actual project as an example, the fixed automatic fire extinguishing system in the battery cabin adopts a water mist fire extinguishing system. The total capacity of the battery cabin in this project is 103200 Ah, and 9600 single batteries are built-in. The water consumption of the water mist is about 54m 3 L, and the water consumption converted to the experimental battery capacity (100 Ah) is about 52 L, which is greater than the experimental water consumption of 15 L. The perfluorohexone gas fire extinguishing system can only extinguish the initial fire, and a semi-fixed open water spray system is generally configured for battery cabin immersion fire extinguishing. Taking another actual project as an example, 7920 single batteries with a rated capacity of 150 Ah are built-in the energy storage battery cabin, and the semi-fixed open water spray system is used to immerse the entire cabin (specifications: L x B x H = 12.2m x 2.4m x 2.8m) with water about 82m 3 L, and the water consumption converted to the experimental battery capacity (100 Ah) is about 52 L, which is greater than the experimental water consumption of 15 L. The experimental data, engineering data and standard data comparison table is shown in Table 3.

[0105] Table 3 Comparison table of experimental data, engineering data and standard data

[0106]

[0107]

[0108] As can be seen from Table 3, the concentration of fire-fighting drainage pollutants in the project is far lower than the standard data, and individual indicators exceed the standard, such as fluorine, SS, COD, total phosphorus, etc. Considering that fire-fighting drainage is a kind of emergency drainage under abnormal conditions, its total wastewater volume is limited, and the damage to the environment can be controlled within a certain range. For environmentally sensitive areas, considering the toxicity of fluorine and other elements, it is recommended to collect and store the fire-fighting drainage, and use mobile sewage treatment devices for on-site treatment or transport to qualified sewage treatment units for treatment.

[0109] The 100 Ah capacity lithium iron phosphate battery used in the experiment was subjected to combustion experiments for lithium iron phosphate batteries with different usage levels and different charging levels, and 15 L (corrected value) of municipal tap water was used to extinguish the fire.

[0110] In the combustion experiment and water quality detection, it was found that:

[0111] (1) pH value changes little, considering the fire drainage as a neutral liquid.

[0112] (2) The main heavy metal elements contained are copper, nickel, chromium, lead and manganese. The concentration of lead and manganese is very low, which can be regarded as trace; the content of copper and chromium is relatively high; the measured indicators do not exceed the values specified in the wastewater discharge into urban sewer water quality standards and battery industry pollutant emission standards.

[0113] (3) The concentration of arsenic does not exceed the requirements of wastewater discharge into urban sewer water quality standards and battery industry wastewater total arsenic emission standards.

[0114] (4) The concentration of fluorine is relatively high, and the fluorine concentration of old battery drainage maintains at about 150-200 mg / L.

[0115] (5) The total phosphorus concentration is relatively high, and the minimum of the charged battery exceeds 100 mg / L.

[0116] (6) The COD concentration is high, and the value is basically between 25-60 g / L.

[0117] (7) The content of total nitrogen and ammonia nitrogen is lower than the emission standard.

[0118] Comparative analysis of experimental data and engineering design parameters: the fire and fire-fighting drainage of lithium iron phosphate battery energy storage power station has the characteristics of most pollutant indicators being lower than the relevant emission standards, individual indicators being slightly high but the total amount of pollutants being relatively small, and in the fire state emergency discharge, it will not cause serious environmental pollution. For the energy storage power station constructed in the area with higher environmental protection requirements, it is recommended to collect the wastewater and use mobile wastewater treatment device for on-site treatment or external treatment.

[0119] The above is only the preferred embodiment of the present application, and it should be pointed out that for ordinary skilled persons in the technical field, several improvements and modifications can be made without departing from the technical principles of the present application, and these improvements and modifications should also be regarded as the protection scope of the present application.

Claims

1. A method for detecting the quality of water in the fire-fighting drainage of an electrochemical energy storage power plant, characterized in that, The method comprises the following steps: simulate the combustion and extinguishing of the battery under various working conditions through experiments; collect the water samples of the fire-fighting drainage after extinguishing and detect the water samples to obtain the water quality data of the fire-fighting drainage of the battery under various working conditions; compare the water quality data with the engineering design parameters to obtain the water quality detection result of the fire-fighting drainage of the electrochemical energy storage power station; the working conditions include: battery fires of different use degrees, battery fires of different SOC states, battery fires of different combustion times, and any combination of the three kinds of battery fires; simulate the combustion and extinguishing of the battery under various working conditions through experiments, which comprises the following steps: take single batteries as the experimental objects, mark the unused batteries as group A batteries and mark the used batteries as group B batteries; use a charge-discharge tester to charge or discharge the group A batteries and the group B batteries to various SOC states at the same preset current; cause the group A batteries and the group B batteries at various SOC states to thermal runaway until combustion; extinguish the group A batteries and the group B batteries that are combusting; wherein, the group A batteries and the group B batteries each include original batteries and dissection batteries; the method for causing the original batteries of the group A batteries and the group B batteries at various SOC states to thermal runaway until combustion comprises overcharging and heating by an iron plate test device; the method for causing the dissection batteries of the group A batteries and the group B batteries at various SOC states to thermal runaway until combustion comprises artificial ignition.

2. The method for detecting water quality of the fire-fighting drainage of the electrochemical energy storage power station according to claim 1, characterized in that, detecting the collected water samples of the fire-fighting drainage after extinguishing comprises the following steps: use a glass electrode method to detect the pH value of the collected water samples of the fire-fighting drainage after extinguishing; use an atomic absorption spectrophotometry method to detect the heavy metal content of the collected water samples of the fire-fighting drainage after extinguishing; use a dichromate method to detect the chemical oxygen demand of the collected water samples of the fire-fighting drainage after extinguishing; use a weight method to detect the suspended solids content of the collected water samples of the fire-fighting drainage after extinguishing; use an ammonium molybdate spectrophotometry method to detect the total phosphorus of the collected water samples of the fire-fighting drainage after extinguishing; use a gas-phase molecular absorption method to detect the ammonia nitrogen and total nitrogen of the collected water samples of the fire-fighting drainage after extinguishing.

3. The method of claim 1, wherein the water quality of the fire water drain of the electrochemical energy storage plant is determined by measuring the pH of the water. comparing the water quality data with the engineering design parameters to obtain the water quality detection result of the fire-fighting drainage of the electrochemical energy storage power station comprises the following steps: correct the water quality detection result according to a preset amount of fire-fighting water to obtain a corrected water quality detection result; obtain an engineering design proposal scheme according to the corrected water quality detection result.

4. The method for detecting water quality of fire-fighting drainage of an electrochemical energy storage power plant according to any one of claims 1-3, characterized in that, The battery is a lithium battery.

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