CN-121994545-A - On-line measurement method and measurement device for petroleum in water

CN121994545ACN 121994545 ACN121994545 ACN 121994545ACN-121994545-A

Abstract

The invention belongs to the field of water pollution monitoring, and particularly relates to an online measurement method of petroleum in water, which comprises the following steps that firstly, a water sample is taken, a triggering unit transmits fluorescence intensity of the detected water surface to a control unit, and the control unit controls water sample extraction frequency of a sampling pump in the water taking unit according to the fluorescence intensity detected by the triggering unit; the method comprises the steps of extracting, namely, sending a water sample extracted by a sampling pump into a sample storage container to extract oil substances into an extraction reagent, separating, sending the oil substances into a separation container by a conveying pump, and measuring, namely, sending the extraction reagent into a cuvette of a measuring unit to measure the content of the oil substances. The design adopts a method combining water surface early warning measurement and underwater quantitative measurement, can judge pollution in time and measure the content of oil substances in the water on line, thereby being convenient for timely feedback, controlling pollution sources and guaranteeing timeliness of on-line water environment monitoring.

Inventors

ZHANG ZONGKE
ZHANG HONG
LIU XIAOFENG
GUO SHAOWEI

Assignees

上海昂林科学仪器股份有限公司

Dates

Publication Date: 20260508
Application Date: 20260212

Claims (10)

1. An on-line measurement method for petroleum in water is characterized by comprising the following steps: firstly, taking a water sample, transmitting the fluorescence intensity of the detected water surface to a control unit by a trigger unit, and controlling the water sample extraction frequency of a sampling pump in the water taking unit by the control unit according to the fluorescence intensity detected by the trigger unit; Step two, extracting, namely sending the water sample extracted by the sampling pump into a sample storage container, extracting an extraction reagent from an extraction reagent storage tank by an injection pump through a multi-way valve, injecting the extraction reagent into the sample storage container, starting a mixer to mix the water sample in the sample storage container with the extraction reagent, and extracting oil substances into the extraction reagent; Step three, separating, namely pumping mixed liquid of a water sample and an extraction reagent in a sample storage container through a delivery pump, and delivering the mixed liquid into a separation container; And step four, measuring, namely extracting the extraction reagent into the separation container through a multi-way valve by using an injection pump, and sending the extraction reagent into a cuvette of a measuring unit for measuring the content of the oil substances.
2. The method for on-line measurement of petroleum in water according to claim 1, wherein in the first step, when the detected fluorescence intensity does not exceed the set fluorescence threshold value, the control unit enters a timing detection mode and controls the sampling pump of the water intake unit to perform timing water sample extraction through the water intake pipeline; when the detected fluorescence intensity exceeds the set fluorescence threshold value, the control unit enters a high-frequency detection mode and controls the sampling pump of the water taking unit to perform high-frequency water sample extraction through the water taking pipeline.
3. The on-line measurement method of petroleum in water according to claim 1, wherein in the fourth step, when the content of the oil substances measured by the measurement unit is lower than a set detection threshold, the extraction reagent in the cuvette is sent to the extraction reagent storage tank by the injection pump through the multi-way valve; When the content of the oil substances measured by the measuring unit is higher than a set detection threshold, the injection pump sends the extraction reagent in the cuvette to the waste liquid storage tank through the multi-way valve.
4. The method for on-line measurement of petroleum in water according to claim 3, wherein the measuring unit performs the zeroing operation according to the oil content of the extraction reagent in the extraction reagent storage tank after the extraction reagent in the cuvette is sent to the extraction reagent storage tank by the syringe pump through the multi-way valve when the oil content measured by the measuring unit is lower than the set detection threshold.
5. The on-line measurement method of petroleum in water according to claim 1, further comprising the step of washing, when the measurement unit finishes the measurement of the content of the oil substances and the content of the oil substances measured by the measurement unit is higher than a set detection threshold; the whole process cleaning of the sample storage container, the separation container and the cuvette is carried out by the extraction reagent in the reagent storage tank, and the whole process cleaning times of the extraction reagent are judged by the control unit according to the oil substance content measured by the measuring unit; In the next process of measuring the content of the oil substances, firstly, the extraction reagent contrast cell which is used for extracting the oil substances in the separation container is extracted for cleaning, and then, the extraction reagent which is used for extracting the oil substances in the separation container is extracted for measuring the content of the oil substances.
6. An on-line measurement device for oil in water, which is characterized by being used for realizing the on-line measurement method for oil in water according to any one of claims 1-5, and comprising a triggering unit, a water taking unit, an extraction unit, a separation unit, a measurement unit and a control unit; The triggering unit comprises an oil-in-water sensor and is used for detecting oil substances on the water surface by ultraviolet fluorescence method; The water taking unit comprises a water taking pipeline extending into the water, and the water taking pipeline is connected with a sampling pump; The extraction unit comprises a sample storage container, the sample storage container is connected with a sampling pump, the sample storage container is used for receiving the extracted underwater water sample, and a mixer is arranged at one side of the sample storage container; the separation unit comprises a separation container which is connected with the sample storage container through a delivery pump; the measuring unit is connected with the separating container through a multi-way valve and is used for receiving and measuring the extracting reagent of the extracted oil substances in the separating container; The multi-way valve is connected with a sample storage container, an injection pump, an extraction reagent storage tank and a waste liquid storage tank; The control unit is used for receiving the water surface fluorescence intensity acquired by the oil-in-water sensor and controlling and connecting the sampling pump, the mixer, the delivery pump, the multi-way valve, the injection pump and the measuring unit.
7. The on-line measurement device for oil in water according to claim 6, wherein the separation vessel is a vertically arranged separation tube, and the diameter of the separation tube is smaller than the diameter of the sample storage vessel.
8. An in-line measurement apparatus for oil in water as set forth in claim 6, wherein said measurement unit employs an optical measurement instrument connected to a control unit, and said multi-way valve is connected to a cuvette for receiving an extraction reagent in the optical measurement instrument.
9. The on-line measuring device of water petroleum according to claim 8, wherein said measuring unit is an ultraviolet photometer or a fluorescence photometer, said extracting reagent is n-hexane reagent having a specific gravity smaller than that of water, and the upper part of said separating vessel is connected to a multi-way valve via a liquid-extracting tube.
10. The on-line measuring device of petroleum in water according to claim 8, wherein the measuring unit is an infrared photometer, the extracting reagent is tetrachloroethylene reagent with specific gravity greater than that of water, and the lower part of the separating container is connected with the multi-way valve through a liquid extracting pipe.

Description

On-line measurement method and measurement device for petroleum in water Technical Field The invention belongs to the field of water pollution monitoring, and particularly relates to an online measurement method and device for petroleum in water. Background Petroleum pollution is the most frequent pollution in water environment, and on-line measurement of petroleum pollution is of great importance. However, for the current on-line measuring device and method for water environment pollution without petroleum temporarily, for water environments such as rivers, lakes, sea areas and the like, the existing pollution detection method is to drive people to sites where oil pollution occurs, extract underwater water samples to retrieve laboratories, extract the water samples by using organic reagents, and then measure the water samples by adopting an infrared method, an ultraviolet method or a fluorescence method, so that the timeliness is too low, and the pollution sources are often not fed back in time and controlled. Specifically, petroleum is not uniform in water, the current standard measurement method is to collect a water sample at 0.5 m below water for measurement, and most of oil substances float on the water surface, so that petroleum pollutes time consumption, position and pollution degree of the water body below the water surface, the difficulty in on-site water sample extraction of personnel is increased, and the accuracy of a measurement result is difficult to ensure. In addition, because the detection process needs to use an organic reagent to extract a water sample, then the organic reagent for extracting oil substances is separated from the water and then is sent to the measurement equipment for measurement, the steps of sampling, cleaning and the like are difficult to realize under the unmanned operation condition, for example, the determination of sampling time and times, the cleaning of the measurement equipment, and the problems of the loss and the supplementation of the organic reagent and the like exist. Disclosure of Invention The invention provides an online measurement method and device for petroleum in water. A method for on-line measurement of petroleum in water includes such steps as taking water sample, transmitting the fluorescence intensity of water surface to control unit by trigger unit, controlling the frequency of sampling water sample by sampling pump, extracting, pumping the extracted water sample to sample container, pumping the extracted reagent to sample container by injection pump, pumping the extracted reagent to sample container, mixing the water sample with extracted reagent, extracting the oil substance, pumping the mixed liquid of water sample and extracted reagent, and measuring the content of oil substance. In the first step, when the detected fluorescence intensity does not exceed the set fluorescence threshold value, the control unit enters a timing detection mode and controls the sampling pump of the water taking unit to perform timing water sample extraction through the water taking pipeline, and when the detected fluorescence intensity exceeds the set fluorescence threshold value, the control unit enters a high-frequency detection mode and controls the sampling pump of the water taking unit to perform high-frequency water sample extraction through the water taking pipeline. In the fourth step, when the oil content measured by the measuring unit is lower than a set detection threshold, the injection pump sends the extraction reagent in the cuvette to the extraction reagent storage tank through the multi-way valve, and when the oil content measured by the measuring unit is higher than the set detection threshold, the injection pump sends the extraction reagent in the cuvette to the waste liquid storage tank through the multi-way valve. Further, when the oil content measured by the measuring unit is lower than the set detection threshold, and after the extraction reagent in the cuvette is sent to the extraction reagent storage tank by the injection pump through the multi-way valve, the measuring unit performs zero-resetting operation according to the oil content of the extraction reagent in the extraction reagent storage tank. Further, the method further comprises the step five of cleaning, and when the oil substance content measured by the measuring unit is higher than a set detection threshold value after the measuring unit finishes the oil substance content measurement; and in the next oil content measurement process, firstly extracting the extraction reagent which has extracted the oil substances in the separation container to clean the cuvette, and then extracting the extraction reagent which has extracted the oil substances in the separation container to measure the oil content. The device comprises a triggering unit, a water taking unit, an extraction unit, a separation unit, a measuring unit and a control unit, wherein the triggering unit comprises an oil-in