CN111781053A

CN111781053A - Water sample pretreatment device, water sample pretreatment system and water sample pretreatment method

Info

Publication number: CN111781053A
Application number: CN202010549245.5A
Authority: CN
Inventors: 文立群; 李智; 郭珍; 张卫斌
Original assignee: Lihero Technology Hunan Co ltd
Current assignee: Lihero Technology Hunan Co ltd
Priority date: 2020-06-16
Filing date: 2020-06-16
Publication date: 2020-10-16
Anticipated expiration: 2040-06-16
Also published as: CN111781053B; WO2021254380A1

Abstract

The invention discloses a water sample pretreatment device, a water sample pretreatment system and a water sample pretreatment method, which comprise the following steps: the water tank is communicated with an active water supply device and a water distribution device, the water distribution device is used for distributing supernatant in the water tank into the detection instrument, and the active water supply device and the water distribution device are respectively connected with the control device. The water tank is internally provided with a turbidity detector which is used for detecting the turbidity of source water or the turbidity of supernatant in real time, and the turbidity detector is connected with the control device. The water distribution device is communicated with a secondary treatment device, the secondary treatment device is used for pretreating the supernatant delivered by the water distribution device so that the turbidity value of the supernatant delivered into the detection instrument is equal to or less than a system preset threshold value, and the secondary treatment device is connected with the control device.

Description

Water sample pretreatment device, water sample pretreatment system and water sample pretreatment method

Technical Field

The invention relates to the field of water pollution monitoring and hydrological observation, in particular to a water sample pretreatment device. In addition, the invention also relates to a water sample pretreatment system with the water sample pretreatment device and a water sample pretreatment method for water sample treatment by using the water sample pretreatment system.

Background

In recent years, the government has increased the degree of ecological environment protection measures, the strictest ecological environment protection system and the strictest ecological environment protection responsibility system are implemented, in order to further promote the water pollution prevention and treatment work, standardize the urban surface water environment quality ranking and information distribution and strengthen the public supervision, the ecological environment department has issued the technical specification (trial implementation) of urban surface water environment quality ranking according to the comprehensive, objective, fair and standardized principles, so that the water quality automatic station participating in ranking is required, and the monitoring data of the station has good consistency and transverse comparability.

Turbidity, that is, the degree of obstruction of particles in water to light penetration, has an important influence on the accuracy of the measurement result of a photometric water quality analyzer, and conventional water quality analyzers mostly adopt the photometric measurement principle. In order to reduce the influence of turbidity to water sample detection, at present, the water station all is equipped with pretreatment systems, mainly removes aquatic particulate matter through modes such as subsiding, filtering, dispelling. Standing and settling are the preferred pretreatment mode because the representativeness of the water sample can be ensured to the maximum extent. How to ensure comparability of monitoring data of water stations all over the country must first solve the problem of consistency of water sample pretreatment conditions of each station. In general, the main factors influencing the sedimentation pretreatment effect include sedimentation time, sedimentation mode, water intake depth and the like. However, the integrated manufacturers of the national water stations are different, the design concepts and pretreatment processes of the manufacturers are greatly different, and the problems that the sedimentation water tanks 10 are different in morphological structure and different in sampling depth and the pretreatment conditions are inconsistent are particularly reflected, the transverse comparability of monitoring data of each station is fundamentally influenced, and meanwhile, the objectivity and fairness of the urban surface water environment quality ranking are also adversely affected.

A common water sample pretreatment mode of an existing automatic water quality monitoring station (hereinafter referred to as a water station) is standing and sedimentation, and all stations stand uniformly for 30min no matter the turbidity of a water sample and then start an instrument for testing. Different website water sample turbidity probably has great difference, and the turbidity of supernatant is also different after the unified settlement of standing for 30min, and the difference of test result can be brought for some instruments to the turbidity difference of supernatant layer, but the pretreatment methods of current water station can't guarantee that each website monitoring data obtains under same turbidity condition, and this has just caused behind the water sample that obtains between different websites, when going on detecting after the pretreatment, the turbidity of water sample is different. That is, the components and conditions of the water sample to be detected are not the same, which directly results in the differentiation of the detection results.

This also constitutes a need for further improvements in the design of water sample pretreatment devices to address the existing technical problems.

Disclosure of Invention

The invention provides a water sample pretreatment device and a water sample pretreatment system with the same, and aims to solve the technical problems that the condition consistency and comparability of monitoring data among stations are poor due to the fact that the pretreatment mode of the existing water station cannot ensure that the monitoring data of all stations are obtained under the same turbidity condition.

The technical scheme adopted by the invention is as follows:

a water sample pretreatment device for performing stationary sedimentation pretreatment on source water so that the turbidity of a water sample fed into a detection instrument at each station is the same, comprising: the water tank is communicated with an active water supply device, the water tank is also communicated with a water distribution device, the water distribution device is used for distributing supernatant formed after the source water in the water tank is settled and settled into the detection instrument, and the source water supply device and the water distribution device are respectively connected with the control device; a turbidity detector for detecting the turbidity of the source water or the turbidity of the supernatant in real time is arranged in the water tank, the turbidity detector is connected with the control device so as to send the detected turbidity value of the source water or the turbidity value of the supernatant to the control device, and the control device is used for controlling the water distribution device to be started after first preset sedimentation time to distribute the supernatant into the detection instrument when the received turbidity value of the source water is equal to or less than a primary threshold value preset by the system; the control device is also used for controlling the water distribution device to be started after second preset settling time so as to distribute the supernatant into the detection instrument when the turbidity value of the received source water is greater than a primary threshold value and less than a secondary threshold value preset by the system; the control device is also used for controlling the water distribution device to be started when the turbidity value of the supernatant is equal to or less than the primary threshold value preset by the system within third preset settling time when the turbidity value of the received source water is greater than the primary threshold value preset by the system, so that the supernatant is distributed into the detection instrument; the water distribution device is communicated with a secondary treatment device, the secondary treatment device is used for pretreating the supernatant delivered by the water distribution device, the secondary treatment device is connected with the control device, and the control device is also used for controlling the secondary treatment device to be started when the turbidity value of the received source water is equal to or greater than a secondary threshold value preset by the system or the turbidity value of the supernatant is still greater than a primary threshold value preset by the system after a third preset settling time, so as to pretreat the supernatant delivered by the water distribution device.

Furthermore, the water distribution device comprises a water taking head which is arranged in the water tank and used for absorbing supernatant, the output end of the water taking head is connected with a water taking hose, the output end of the water taking hose is connected with a water distribution pipe, and the output end of the water distribution pipe extends out of the water tank and then is connected with a detection instrument so as to distribute the supernatant into the detection instrument; the water distribution pipe is provided with a second pump transmitter for pumping supernatant fluid, a first filter for filtering the supernatant fluid, a second switch valve for controlling the conduction or the partition of the water distribution pipe, a second regulating valve for regulating the flow of the water distribution pipe, a water sample cup for temporarily storing the supernatant fluid, and a reversing valve which is positioned at the downstream of the water sample cup and is used for controlling the conduction or the partition of a pipeline between the water sample cup and a detection instrument, wherein the second pump transmitter, the first filter, the second switch valve, the second regulating valve and the reversing valve are respectively connected with the control device.

Further, a turbidity detector is connected to the water intake head to detect a source water turbidity value of the source water at the water intake head or a supernatant turbidity value of the supernatant; the water distribution device further comprises a lifting adjusting member for adjusting the height of the water intake head, and the lifting adjusting member comprises: the lifting device comprises a lifting driver connected to the outer surface of an upper cover of the water tank, a wire conveying rod vertically arranged in the water tank, and a guide shaft rod vertically arranged on the inner side wall of the water tank and used for guiding the up-and-down movement of a water taking head, wherein the upper end of the wire conveying rod is fixedly connected with the driving end of the lifting driver; the water taking head is respectively arranged on the outer circles of the wire guide rod and the guide shaft rod in a penetrating mode, and the water taking head is in threaded connection with the outer circle of the wire guide rod.

Furthermore, the secondary treatment device comprises a water conduit for guiding and taking supernatant, the input end of the water conduit is communicated with the water sample cup, and the output end of the water conduit is communicated with the reversing valve; a second filter for carrying out secondary filtration on the supernatant and a fixed-volume bottle for temporarily containing the filtered supernatant are arranged in the pipeline of the water conduit, and the second filter is connected with the control device; the constant volume bottle is communicated with a suction pipe, the suction end of the suction pipe is connected with a suction pump which is used for generating negative pressure in the water diversion pipe to suck supernatant, and the suction pump is connected with the control device.

Furthermore, the water sample pretreatment device also comprises a system drainage device, wherein the system drainage device comprises a waste liquid recovery tank for containing waste liquid, a first overflow pipe, a first sample discharge pipe, a second sample discharge pipe, a third sample discharge pipe, a second overflow pipe and a fourth sample discharge pipe; two ends of the first overflow pipe are respectively communicated with the inner cavity side of the water tank and the waste liquid recovery tank; two ends of the first sample discharge pipe are respectively communicated with the bottom of the inner cavity of the water tank and the waste liquid recovery tank, and a third switch valve for connecting or disconnecting the first sample discharge pipe is arranged in a pipeline of the first sample discharge pipe; two ends of the second sample discharge pipe are respectively communicated with the first filter and the waste liquid recovery tank, and a fourth switch valve for connecting or disconnecting the second sample discharge pipe is arranged in a pipeline of the second sample discharge pipe; two ends of the third sample discharge pipe are respectively communicated with the bottom of the inner cavity of the water sample cup and the waste liquid recovery tank, and a fifth switch valve for connecting or disconnecting the third sample discharge pipe is arranged in a pipeline of the third sample discharge pipe; two ends of the second overflow pipe are respectively communicated with the side wall of the water sample cup and the waste liquid recovery tank; two ends of the fourth sample discharge pipe are respectively communicated with the bottom of the fixed-volume bottle and the waste liquid recovery tank, and a sixth switch valve for connecting or disconnecting the fourth sample discharge pipe is arranged in a pipeline of the fourth sample discharge pipe; the third switch valve, the fourth switch valve, the fifth switch valve and the sixth switch valve are respectively connected with the control device.

Furthermore, the water sample pretreatment device also comprises a cleaning device, wherein the cleaning device comprises a cleaning water supplier for supplying cleaning water, and the cleaning water supplier is connected with a water supply main pipe, a first water supply branch pipe and a second water supply branch pipe which are respectively communicated with the water supply main pipe; a fifth regulating valve for regulating the flow of the water supply main pipe is arranged in the pipeline of the water supply main pipe; the output end of the first water supply branch pipe is communicated with the source water input pipe, and an eighth switch valve for connecting or disconnecting the first water supply branch pipe is arranged in a pipeline of the first water supply branch pipe; the output end of the second water supply branch pipe is communicated with the water taking pipe, and a ninth switch valve for connecting or disconnecting the second water supply branch pipe is arranged in a pipeline of the second water supply branch pipe; the cleaning water supplier, the fifth regulating valve, the eighth switch valve and the ninth switch valve are respectively connected with the control device.

Furthermore, the cleaning device also comprises a third water supply branch pipe, the input end of the third water supply branch pipe is communicated with the second water supply branch pipe, the output end of the third water supply branch pipe penetrates through the upper cover of the water tank and then extends into the water tank, a tenth switch valve for controlling the conduction or the partition of the third water supply branch pipe is arranged in a pipeline of the third water supply branch pipe, and the tenth switch valve is connected with the control device; the output end of the third water supply branch pipe is communicated with a self-rotating spray head which automatically rotates under the action of cleaning water pressure, and the self-rotating spray head is communicated with a plurality of nozzles; the water sample pretreatment device further comprises a back flushing device, the back flushing device comprises an air flushing pipe communicated with the first sample discharging pipe, the input end of the air flushing pipe is communicated with a compressed air supply device used for supplying compressed air, an eleventh switch valve used for controlling the conduction or the separation of the air flushing pipe and a third adjusting valve used for adjusting the flow of the air flushing pipe are arranged in a pipeline of the air flushing pipe, and the compressed air supply device, the eleventh switch valve and the third adjusting valve are respectively connected with the control device.

According to another aspect of the invention, a water sample pretreatment system is further provided, which comprises the water sample pretreatment device as described in any one of the above, and a detection instrument for detecting and analyzing the water sample treated by the water sample pretreatment device, wherein the detection instrument is communicated with the output end of the water distribution device of the water sample pretreatment device.

According to another aspect of the present invention, there is also provided a water sample pretreatment method, which is performed by using the water sample pretreatment system as described above, and includes the following steps: s1: the control device controls the starting of the source water supply device and supplies source water into the water tank; s2: the turbidity detector detects the turbidity value of the source water, the control device correspondingly controls the water distribution device to be started after different sedimentation time according to different turbidity values, and when the turbidity value of the source water detected by the turbidity detector is equal to or greater than a secondary threshold value preset by the system or the turbidity value of the supernatant is still greater than a primary threshold value preset by the system after third preset sedimentation time, the control device controls the secondary treatment device to start to carry out pretreatment on the delivered supernatant, so that the turbidity value of the supernatant distributed into the detection instrument is equal to or less than the preset threshold value of the system.

Further, step S2 specifically includes the following steps: a turbidity detector arranged in the water tank detects the turbidity value of the source water, and when the turbidity value of the source water is equal to or less than a primary threshold value preset by the system, the control device controls the water distribution device to be started after first preset sedimentation time so as to distribute the supernatant into the detection instrument; when the turbidity value of the source water is larger than a primary threshold value preset by the system and smaller than a secondary threshold value preset by the system, the control device controls the water distribution device to be started after second preset settling time, so that the supernatant is distributed into the detection instrument; when the turbidity value of the source water is greater than a primary threshold value preset by the system, the control device controls the water distribution device to be started when the turbidity value of the supernatant is equal to or less than the primary threshold value preset by the system within third preset settling time so as to distribute the supernatant into the detection instrument; when the turbidity value of the source water detected by the turbidity detector is equal to or greater than a secondary threshold value preset by the system, or the turbidity value of the supernatant after a third preset settling time is still greater than a primary threshold value preset by the system, the control device controls the secondary treatment device to be started so as to filter, centrifuge or dilute the supernatant delivered by the water distribution device.

The invention has the following beneficial effects:

the water sample pretreatment device provided by the invention changes the static sedimentation pretreatment mode of the existing water station with fixed time length, expands the sedimentation mode with the turbidity value of the supernatant layer as the condition, namely controls the water distribution device to start when the turbidity value of the supernatant is equal to or less than the preset threshold value of the system within the third preset sedimentation time, and can effectively shorten the sedimentation time compared with the sedimentation with the time as the condition, thereby improving the sedimentation pretreatment efficiency. During actual treatment, when the turbidity value of source water is lower than a preset threshold value of the system, the influence of turbidity on a test result of a detection instrument is small, so that monitoring data of each water station has good consistency; when the turbidity value of the source water is larger than a preset threshold value of the system, the turbidity has large influence on a test result of a detection instrument, the consistency of monitoring data of each water station is poor, and under the condition that the turbidity of the source water is higher (influencing the test result of the detection instrument), each water station can uniformly adopt a turbidity threshold value as a condition to settle and unify the preset turbidity threshold value standard of the system, so that the monitoring data of each water station can be obtained under the same turbidity condition, the consistency and comparability of data among stations are improved, and the quality evaluation of the surface water environment of each province and city is more objective.

In addition to the objects, features and advantages described above, other objects, features and advantages of the present invention are also provided. The present invention will be described in further detail below with reference to the drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic diagram of a spatial structure of a water sample pretreatment device according to a preferred embodiment of the present invention;

FIG. 2 is a schematic illustration of the water circuit of FIG. 1;

FIG. 3 is a flow chart of the time-conditioned sedimentation of FIG. 1;

FIG. 4 is a flow chart of the sedimentation process in FIG. 1 conditioned on turbidity values;

FIG. 5 is a schematic view of the spatial structure of the first filter of FIG. 1;

fig. 6 is a sectional front view structural diagram of fig. 5.

Description of the figures

10. A water tank; 20. a source water supply device; 21. a source water input pipe; 22. a first pump feeder; 23. a first on-off valve; 24. a first regulating valve; 25. a shunt tube; 26. a fourth regulating valve; 30. a water distribution device; 31. a water intake head; 32. a water intake hose; 33. a water distribution pipe; 34. a second pump feeder; 35. a first filter; 351. a filter box; 3511. a liquid inlet; 3512. a liquid outlet; 3513. a liquid discharge port; 3514. a filtration front chamber; 3515. a rear filtering cavity; 352. a filter mesh sheet; 353. an ultrasonic vibrator; 36. a second on-off valve; 37. a second regulating valve; 38. a water sample cup; 39. a diverter valve; 41. a lift adjustment member; 411. a lift drive; 412. a wire feeding rod; 413. a guide shaft lever; 50. detecting an instrument; 60. a turbidity detector; 70. a secondary treatment device; 71. a water conduit; 72. a second filter; 73. a fixed volume bottle; 74. a suction tube; 75. a suction pump; 80. a system drain; 81. a first overflow pipe; 82. a first sample discharge pipe; 83. a second sample discharge pipe; 84. a third sample discharge pipe; 85. a second overflow tube; 86. a fourth sample discharge pipe; 87. a third on-off valve; 88. a fourth switching valve; 89. a fifth on-off valve; 91. a sixth switching valve; 110. a cleaning device; 111. a water main; 112. a first water supply branch pipe; 113. a second water supply branch pipe; 114. a fifth regulating valve; 115. an eighth on-off valve; 116. a ninth on-off valve; 117. a third water supply branch pipe; 118. a tenth switching valve; 119. a self-rotating nozzle; 120. a nozzle; 130. a back flushing device; 131. a gas washing pipe; 132. an eleventh switching valve; 133. and a third regulating valve.

Detailed Description

The embodiments of the invention will be described in detail below with reference to the accompanying drawings, but the invention can be embodied in many different forms, which are defined and covered by the following description.

Referring to fig. 1 to 4, a preferred embodiment of the present invention provides a water sample pretreatment apparatus for performing stationary sedimentation pretreatment on source water so that the turbidity of water samples fed into a detection instrument 50 at respective sites is the same, the water sample pretreatment apparatus including: the device comprises a water tank 10, wherein the water tank 10 is communicated with an active water supply device 20, the water tank 10 is also communicated with a water distribution device 30, the water distribution device 30 is used for distributing supernatant formed after the source water is stood and settled in the water tank 10 into a detection instrument 50, and the active water supply device 20 and the water distribution device 30 are respectively connected with a control device; a turbidity detector 60 for detecting the turbidity of the source water or the turbidity of the supernatant in real time is arranged in the water tank 10, the turbidity detector 60 is connected with a control device to send the detected turbidity value of the source water or the turbidity value of the supernatant to the control device, and the control device is used for controlling the water distribution device 30 to be started after first preset settling time to distribute the supernatant into the detection instrument 50 when the received turbidity value of the source water is equal to or less than a primary threshold value preset by the system; the control device is also used for controlling the water distribution device 30 to be started after second preset settling time to distribute the supernatant into the detection instrument 50 when the turbidity value of the received source water is greater than a primary threshold value and less than a secondary threshold value preset by the system; the control device is further configured to control the water distribution device 30 to be started when the turbidity value of the supernatant is equal to or less than the primary threshold value preset by the system within a third preset settling time when the turbidity value of the received source water is greater than the primary threshold value preset by the system, so as to distribute the supernatant into the detection instrument 50; the water distribution device 30 is communicated with a secondary treatment device 70, the secondary treatment device 70 is used for pretreating the supernatant liquid distributed by the water distribution device 30, the secondary treatment device 70 is connected with a control device, and the control device is also used for controlling the secondary treatment device 70 to be started when the turbidity value of the received source water is equal to or greater than a secondary threshold value preset by the system or the turbidity value of the supernatant liquid is still greater than a primary threshold value preset by the system after a third preset settling time, so as to pretreat the supernatant liquid distributed by the water distribution device 30.

When the water sample pretreatment device works, the source water supply device 20 is started under the control of the control device, the source water to be pretreated is supplied into the water tank 10, the turbidity detector 60 arranged in the water tank 10 detects the turbidity value of the source water, when the turbidity value of the source water is equal to or less than a first-level threshold value (which can be an upper turbidity threshold value allowed by a detection instrument) preset by the system, the control device enables the source water to be settled for a first preset settling time (generally 30min) according to the relevant requirements of the ground surface water environment quality standard (GB3838-2002), then the water distribution device 30 is controlled to be started, and supernatant formed after the source water is settled is distributed into the detection instrument 50. When the turbidity value of the source water is greater than a primary threshold value preset by the system and less than a secondary threshold value preset by the system, the pretreatment system can perform sedimentation according to the condition of time, the sedimentation flow chart is shown in fig. 3, when the sedimentation time of the source water reaches a second preset sedimentation time (generally 60min), the control device controls the water distribution device 30 to be started, and supernatant formed after the source water is sedimented is distributed into the detection instrument 50; when the turbidity value of the source water is greater than the first-level threshold value preset by the system, the sedimentation flow chart is as shown in fig. 4, and in the third preset sedimentation time of the source water, when the turbidity value of the supernatant water sample formed after sedimentation is equal to or less than the first-level threshold value preset by the system, the control device controls the water distribution device 30 to be started, and the supernatant is distributed into the detection instrument 50. When the source water is settled under the condition of time or the turbidity value is settled under the condition of time and the water distribution device 30 is started, the turbidity value of the supernatant detected by the turbidity detector 60 is equal to or greater than a second-level threshold value preset by the system or is still greater than a first-level threshold value preset by the system after the third preset settling time, the control device controls the secondary treatment device to be started again, the secondary treatment device 70 carries out pretreatment on the supernatant distributed by the water distribution device 30, and then the turbidity value of the supernatant distributed into the detection instrument 50 is equal to or less than the first-level threshold value preset by the system, so that the turbidity value of the supernatant distributed into the detection instrument 50 meets the requirement of the detection instrument 50.

The water sample pretreatment device changes the static sedimentation pretreatment mode of the existing water station with fixed time length, expands the sedimentation mode with the turbidity value of the supernatant layer as the condition, namely, controls the water distribution device 30 to start when the turbidity value of the supernatant is equal to or less than the preset threshold value of the system in the third preset sedimentation time, and can effectively shorten the sedimentation time compared with the sedimentation with the time as the condition so as to improve the sedimentation pretreatment efficiency. During actual treatment, when the turbidity value of source water is lower than a preset threshold value of the system, the influence of turbidity on a test result of a detection instrument is small, so that monitoring data of each water station has good consistency; when the turbidity value of the source water is larger than a preset threshold value of the system, the turbidity has large influence on a test result of a detection instrument, the consistency of monitoring data of each water station is poor, and under the condition that the turbidity of the source water is higher (influencing the test result of the detection instrument), each water station can uniformly adopt a turbidity threshold value as a condition to settle and unify the preset turbidity threshold value standard of the system, so that the monitoring data of each water station can be obtained under the same turbidity condition, the consistency and comparability of data among stations are improved, and the quality evaluation of the surface water environment of each province and city is more objective.

Alternatively, as shown in fig. 1 and 2, the source water supply device 20 includes a source water input pipe 21, an input end of the source water input pipe 21 is a source water taking point, and an output end of the source water input pipe 21 is communicated to the inside of the water tank 10. The pipeline of the source water input pipe 21 is provided with a first pump feeder 22 for pumping source water, a first switch valve 23 for controlling the conduction or the partition of the source water input pipe 21, and a first regulating valve 24 for regulating the flow of the source water input pipe 21, and the first pump feeder 22, the first switch valve 23 and the first regulating valve 24 are respectively connected with the control device. Preferably, the output end of the source water input pipe 21 horizontally extends into the water tank 10 along the tangential direction of the cylindrical water tank 10, the source water is tangentially fed to form a vortex, so that the particles contained in the source water gather towards the center of the water tank 10 under the action of centripetal force, impurities are not easily attached to the inner wall of the water tank 10, and compared with the turbulent flow generated when the particles are fed in the direction of the vertical side wall of the traditional water tank, the particles contained in the source water can be orderly settled by the feeding mode along the tangential direction, and the settling time is further shortened. Preferably, as shown in fig. 2, the source water supply device 20 further includes a shunt pipe 25 and a fourth regulating valve 26, an input end of the shunt pipe 25 is communicated with the source water input pipe 21, an output end of the shunt pipe 25 is communicated with a system drainage device for containing waste liquid, the fourth regulating valve 26 is disposed in a pipeline of the shunt pipe 25 for controlling a flow rate of the shunt pipe 25, and the fourth regulating valve 26 is connected with the control device, the shunt pipe 25 is used for shunting the source water input pipe 21. Specifically, the first pump feeder 22 is a water pump, the first switching valve 23 is an electric valve, the first regulating valve 24 is a flow valve, and the fourth regulating valve 26 is a flow valve.

Alternatively, as shown in fig. 1 and 2, the water distribution device 30 includes a water intake head 31 disposed in the water tank 10 for sucking the supernatant, a water intake hose 32 is connected to an output end of the water intake head 31, a water distribution pipe 33 is connected to an output end of the water intake hose 32, and a detection instrument 50 is connected to an output end of the water distribution pipe 33 after extending out of the water tank 10 to distribute the supernatant into the detection instrument 50. The extended section of the water distribution pipe 33 extending out of the water tank 10 is provided with a second pump 34 for pumping supernatant, a first filter 35 for filtering the supernatant, a second switch valve 36 for controlling the conduction or the interruption of the water distribution pipe 33, a second regulating valve 37 for regulating the flow of the water distribution pipe 33, a water sample cup 38 for temporarily storing the supernatant, and a reversing valve 39 located at the downstream of the water sample cup 38 for controlling the conduction or the interruption of a pipeline between the water sample cup 38 and the detection instrument 50, wherein the second pump 34, the first filter 35, the second switch valve 36, the second regulating valve 37 and the reversing valve 39 are respectively connected with a control device. Specifically, the second pump transmitter 34 is a water pump, the second switching valve 36 is an electric valve, the second regulating valve 37 is a flow valve, and the change valve 39 is a three-way electromagnetic valve. After the standing and sedimentation is finished, the control device controls the water distribution device 30 to act, the second pump 34 is started, the supernatant in the water tank 10 enters the water taking hose 32 through the water taking head 31, then enters the water distribution pipe 33, enters the water sample cup 38 after being filtered by the first filter 35, and finally enters the detection instrument 50 through the water sample cup 38. Preferably, be equipped with the micropore filter screen in the water intaking head, filter the water sample.

In this alternative, as shown in fig. 5 and 6, the first filter 35 includes a filter tank 351 having a filter cavity, the filter tank 351 is provided with a liquid inlet 3511, a liquid outlet 3512 and a liquid discharge port 3513 which are respectively communicated with the filter cavity, the water distribution pipe 33 extends out of the water tank 10 and is communicated with the liquid inlet 3511, the liquid outlet 3512 is communicated with the detection instrument 50 through the water distribution pipe 33, and the liquid discharge port 3513 is communicated with a system drainage device 80 for containing waste liquid. The filter cavity is internally provided with a filter net piece 352 for filtering the entered supernatant, the filter net piece 352 is obliquely arranged to divide the filter cavity into a front filter cavity 3514 and a rear filter cavity 3515, the liquid inlet 3511 and the liquid outlet 3513 are respectively communicated with the front filter cavity 3514, and the liquid outlet 3512 is communicated with the rear filter cavity 3515. The filter tank 351 is also connected with an ultrasonic vibrator 353 for generating vibration, and the ultrasonic vibrator 353 is connected with a control device. Specifically, as shown in fig. 6, the filter tank 351 is a rectangular tank, the filter chamber is a rectangular chamber, and the filter mesh 352 is provided along a diagonal of the rectangular chamber. When a water sample is filtered, impurities are blocked by the obliquely arranged filter net 352 and are taken away by a shunted water sample from the liquid outlet 3513, so that the impurities are not easy to attach to the surface of the filter net; after the water sample is filtered, cleaning water can be filled into the filtering cavity from the water outlet 3512, the cleaning water is discharged from the water outlet 3513, the filtering net 352 is cleaned reversely, the ultrasonic vibrator is started during reverse cleaning, and the cavitation effect of the ultrasonic waves in the water body further enhances the cleaning effect.

In this alternative, as shown in fig. 2, a turbidity detector 60 is connected to the water intake head 31 to detect the turbidity value of the source water at the water intake head 31 or the turbidity value of the supernatant, so as to ensure real-time interpretation of the turbidity value of the supernatant. Water distribution device 30 further comprises a lifting adjustment member 41 for adjusting the height of water intake head 31, lifting adjustment member 41 comprising: connect lift driver 411 on the surface of water tank 10 upper cover, vertically set up in water tank 10 and upper end and lift driver 411's drive end fixed connection's conduction silk pole 412, and vertically set up be used for carrying out the direction guide shaft lever 413 to the reciprocating of water intaking head 31 on the inside wall of water tank 10, lift driver 411 links to each other with controlling means. The water intake 31 is respectively arranged on the outer circles of the wire transmission rod 412 and the guide shaft 413 in a penetrating way, and the water intake 31 is in threaded connection with the outer circle of the wire transmission rod 412. Specifically, the elevating driver 411 is an elevating motor, and the water intake hose 32 ensures movement of the water intake head 31 at different water depth positions. In the present invention, the elevation adjusting member 41 is provided to further adjust the water intake depth of the water intake head 31, thereby realizing the turbidity detection of different water depths (water layers) by the turbidity detector 60.

Preferably, the water distribution device 30 further comprises a water depth detector for detecting the sampling depth of the water intake head 31, and the water depth detector is connected to the water intake head 31 and connected to the control device to send the detected sampling depth value of the water intake head 31 to the control device. The control device receives the sampling depth value, calculates the total volume of the supernatant required by detection according to the number of the detection instruments 50, simultaneously calculates the sampling depth of the water intake head 31 by matching with the size data of the water tank 10, and finally controls the lifting driver 411 to act so as to enable the water intake head 31 to lift to the corresponding sampling depth, thereby realizing automatic adjustment of the sampling head 31 to the minimum sampling depth according to the number of the configured detection instruments, so as to obtain a water sample meeting the sedimentation effect in the shortest time, and simultaneously realizing the adaptive adjustment of the sampling depth of the water intake head 31.

Optionally, the secondary treatment device 70 comprises a water conduit 71 for drawing the supernatant, an input end of the water conduit 71 being in communication with the water sample cup 38, and an output end of the water conduit 71 being in communication with the diverter valve 39. The conduit of the water conduit 71 is provided with a second filter 72 for secondary filtration of the supernatant and a constant volume bottle 73 for temporary containing of the filtered supernatant, and the second filter 72 is connected with a control device. The volumetric flask 73 is communicated with a suction pipe 74, the suction end of the suction pipe 74 is connected with a suction pump 75 for generating negative pressure in the water conduit 71 to suck supernatant, and the suction pump 75 is connected with a control device. When the turbidity value of the prepared supernatant in the water distribution pipe 33 is larger than the preset threshold value of the system, the control device controls the secondary treatment device 70 to be started, the reversing valve 39 is reversed to disconnect the water distribution pipe 33 between the water sample cup 38 and the detection instrument 50 and connect the water guide pipe 71, the suction pump 75 is started, the supernatant in the water sample cup 38 enters the second filter 72 through the water guide pipe 71 under the vacuum pumping action for filtration, the filtered supernatant enters the volumetric flask 73 through the water guide pipe 71 for temporary storage, finally enters the water distribution pipe 33 through the reversing valve 39 from the volumetric flask 73, and finally enters the detection instrument 50 through the water distribution pipe 33. Specifically, the second filter 72 is a device for filtration commonly used in the market, and the suction pump 75 is a vacuum pump.

Optionally, the secondary processing device 70 may also be a diluting device of the detection apparatus 50, and the diluting device selects a preset dilution factor according to the turbidity value of the supernatant, and dilutes the supernatant so that the turbidity value of the diluted supernatant is equal to or lower than a preset threshold value of the system.

Alternatively, the secondary treatment device 70 may also be an automatic centrifugation device, which is connected to the control device. The centrifugal device can suck the supernatant from the water sample cup 38 for centrifugal treatment, the supernatant obtained after centrifugation of the centrifugal device enters the water distribution pipe 33 through the reversing valve 39, and finally enters the detection instrument 50 through the water distribution pipe 33. Preferably, the control device can select a preset centrifugal rotating speed and centrifugal time according to the turbidity value of the supernatant obtained by sedimentation, so that the centrifugal mode and the filtration and dilution mode are basically consistent in pretreatment effect.

Optionally, as shown in fig. 1 and fig. 2, the water sample pretreatment device further comprises a system drainage device 80, and the system drainage device 80 comprises a waste liquid recovery tank for containing waste liquid, a first overflow pipe 81, a first sample discharge pipe 82, a second sample discharge pipe 83, a third sample discharge pipe 84, a second overflow pipe 85, and a fourth sample discharge pipe 86. The two ends of the first overflow pipe 81 are respectively communicated with the inner cavity side direction of the water tank 10 and the waste liquid recovery tank. Two ends of the first sampling pipe 82 are respectively communicated with the bottom of the inner cavity of the water tank 10 and the waste liquid recovery tank, and a third switch valve 87 for conducting or cutting off the first sampling pipe 82 is arranged in a pipeline of the first sampling pipe 82. Both ends of the second sampling pipe 83 are respectively communicated with the first filter 35 and the waste liquid recovery tank, and a fourth switch valve 88 for switching on or off the second sampling pipe 83 is arranged in a pipeline of the second sampling pipe 83. Two ends of the third sampling pipe 84 are respectively communicated with the bottom of the inner cavity of the water sample cup 38 and the waste liquid recovery tank, and a fifth switch valve 89 for switching on or off the third sampling pipe 84 is arranged in a pipeline of the third sampling pipe 84. Both ends of the second overflow pipe 85 are respectively communicated with the side wall of the water sample cup 38 and the waste liquid recovery tank. The two ends of the fourth sampling pipe 86 are respectively communicated with the bottom of the constant volume bottle 73 and the waste liquid recovery tank, and a sixth switch valve 91 for switching on or off the fourth sampling pipe 86 is arranged in the pipeline of the fourth sampling pipe 86. The third switching valve 87, the fourth switching valve 88, the fifth switching valve 89 and the sixth switching valve 91 are connected to a control device, respectively. Specifically, the third switching valve 87 is an air-operated valve, the fourth switching valve 88 is an electric-operated valve, the fifth switching valve 89 is an electromagnetic valve, and the sixth switching valve 91 is an electromagnetic valve. Preferably, an overflow port is formed in the side wall of the water tank 10, and the first overflow pipe 81 is inserted into the overflow port along the tangential direction of the water tank, so that redundant water samples are discharged from the overflow port in the side wall of the water tank 10 along the tangential direction, the sedimentation speed is accelerated, and the sedimentation time is shortened.

Alternatively, as shown in fig. 1 and 2, the water sample pretreatment apparatus further includes a washing apparatus 110, the washing apparatus 110 including a washing water supplier for supplying washing water, the washing water supplier being connected with a water supply main 111, and a first water supply branch pipe 112 and a second water supply branch pipe 113 respectively communicating with the water supply main 111. The pipeline of the water supply main 111 is provided with a fifth adjusting valve 114 for adjusting the flow of the water supply main 111. The output end of the first water supply branch pipe 112 is communicated with the source water input pipe, and an eighth switching valve 115 for switching on or off the first water supply branch pipe 112 is provided in the pipeline of the first water supply branch pipe 112. The output end of the second water supply branch pipe 113 is communicated with the water intake pipe, and a ninth switch valve 116 for connecting or disconnecting the second water supply branch pipe 113 is arranged in the pipeline of the second water supply branch pipe 113. The washing water supplier, the fifth regulator valve 114, the eighth switch valve 115, and the ninth switch valve 116 are connected to the control device, respectively. Specifically, the fifth regulating valve 114 is a flow valve, and the eighth switching valve 115 and the ninth switching valve 116 are both electrically operated valves. In actual operation, the first water supply branch pipe 112 is used for cleaning the source water input pipe 21 and electrical components arranged in the pipeline of the source water input pipe 21; the second water supply branch pipe 113 is used for cleaning the water distribution pipe 33 and electrical components disposed in the pipeline of the water distribution pipe 33.

Optionally, as shown in fig. 1 and 2, the cleaning device 110 further includes a third water supply branch 117, an input end of the third water supply branch 117 is communicated with the second water supply branch 113, an output end of the third water supply branch 117 passes through the upper cover of the water tank 10 and then extends into the water tank 10, a pipeline of the third water supply branch 117 is provided with a tenth switch valve 118 for controlling the third water supply branch 117 to be connected or disconnected, and the tenth switch valve 118 is connected to the control device. The output end of the third water supply branch pipe 117 is communicated with a self-rotating spray head 119 which automatically rotates under the action of washing water pressure, and the self-rotating spray head 119 is communicated with a plurality of nozzles 120. Specifically, the tenth switching valve 118 is an electric valve. The water sample pretreatment device further comprises a back flushing device 130, the back flushing device 130 comprises an air flushing pipe 131 communicated with the first sample discharging pipe 82, the input end of the air flushing pipe 131 is communicated with a compressed air supplier for supplying compressed air, an eleventh switch valve 132 for controlling the conduction or the separation of the air flushing pipe 131 and a third adjusting valve 133 for adjusting the flow of the air flushing pipe 131 are arranged in a pipeline of the air flushing pipe 131, and the compressed air supplier, the eleventh switch valve 132 and the third adjusting valve 133 are respectively connected with the control device. Specifically, the eleventh switching valve 132 is a solenoid valve, and the third regulating valve 133 is a flow valve.

Preferably, the bottom of the water tank 10 is provided with a conical shape, and the large-angle conical bottom structure of the water tank is beneficial to discharging bottom sediments. Before the water tank 10 arranges the sample, compressed air is injected into the water tank 10 through the bottom air washing pipe 131, the hardened sediment at the conical bottom of the water tank can be driven, and the problem that the hardened sediment cannot be arranged when the sediment amount is large is solved. The self-rotating spray head 119 is a trident rotary spray head driven by water power, and can rotate automatically after tap water is introduced under pressure, rotation speed adjustment can be realized by adjusting the inclination angle of the spray nozzle 120, the rotationally dispersed spray water column can realize that the inner wall of the water tank is cleaned without dead angles, and compressed air blown into the bottom of the water tank is matched, so that the settling water tank has a good self-cleaning effect.

Referring to fig. 1 to 4, the preferred embodiment of the present invention further provides a water sample pretreatment system, which comprises the water sample pretreatment device as described in any one of the above, and a detection instrument 50 for detecting and analyzing the water sample treated by the water sample pretreatment device, wherein the detection instrument 50 is communicated with the output end of the water distribution device 30 of the water sample pretreatment device.

Referring to fig. 1 to 4, the preferred embodiment of the present invention also provides a water sample pretreatment method, which is performed by using the water sample pretreatment system as described above, and comprises the following steps:

s1: the control device controls the source water supply device 20 to start, and the source water is supplied into the water tank 10;

s2: the turbidity detector 60 detects the turbidity value of the source water, the control device correspondingly controls the water distribution device 30 to be started after different settling times according to different turbidity values, and when the turbidity value of the source water detected by the turbidity detector 60 is equal to or greater than a second-level threshold value preset by the system or the turbidity value of the supernatant is still greater than a first-level threshold value preset by the system after a third preset settling time, the control device controls the secondary treatment device to start to pre-treat the delivered supernatant so that the turbidity value of the supernatant distributed into the detection instrument 50 is equal to or less than the preset threshold value of the system.

Optionally, step S2 specifically includes the following steps:

a turbidity detector 60 arranged in the water tank 10 detects the turbidity value of the source water, and when the turbidity value of the source water is equal to or less than a primary threshold value preset by the system, the control device controls the water distribution device 30 to be started after first preset settling time, so as to distribute the supernatant into the detection instrument 50;

when the turbidity value of the source water is greater than a primary threshold value preset by the system and less than a secondary threshold value preset by the system, the control device controls the water distribution device 30 to be started after a second preset settling time, so that the supernatant is distributed into the detection instrument 50;

when the turbidity value of the source water is greater than the primary threshold value preset by the system, the control device controls the water distribution device 30 to be started when the turbidity value of the supernatant is equal to or less than the primary threshold value preset by the system within a third preset settling time so as to distribute the supernatant into the detection instrument 50;

when the turbidity value of the source water detected by the turbidity detector 60 is equal to or greater than the second-level threshold value preset by the system or the turbidity value of the supernatant after the third preset settling time is still greater than the first-level threshold value preset by the system, the control device controls the secondary treatment device 70 to be started so as to filter, centrifuge or dilute the supernatant delivered by the water distribution device 30.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A water sample pretreatment device, characterized in that, the water sample pretreatment device includes:

the water tank (10) is communicated with an active water supply device (20), the water tank (10) is also communicated with a water distribution device (30), the water distribution device (30) is used for distributing supernatant formed after standing and settling of source water in the water tank (10) into the detection instrument (50), and the active water supply device (20) and the water distribution device (30) are respectively connected with a control device;

a turbidity detector (60) for detecting the turbidity of the source water or the turbidity of the supernatant in real time is arranged in the water tank (10), the turbidity detector (60) is connected with the control device to send the detected turbidity value of the source water or the turbidity value of the supernatant to the control device, and the control device is used for controlling the water distribution device (30) to be started after first preset settling time to distribute the supernatant into the detection instrument (50) when the received turbidity value of the source water is equal to or smaller than a primary threshold value preset by the system; the control device is also used for controlling the water distribution device (30) to be started after second preset settling time to distribute the supernatant into the detection instrument (50) when the turbidity value of the received source water is greater than a primary threshold value and less than a secondary threshold value preset by the system; the control device is also used for controlling the water distribution device (30) to be started when the turbidity value of the supernatant is equal to or less than the primary threshold value preset by the system within a third preset settling time when the turbidity value of the received source water is greater than the primary threshold value preset by the system, so as to distribute the supernatant into the detection instrument (50);

water distribution device (30) intercommunication has secondary treatment device (70), secondary treatment device (70) be used for to by the supernatant of water distribution device (30) delivery carries out the preliminary treatment, secondary treatment device (70) with controlling means links to each other, controlling means still is used for when the source water turbidity value of receiving equals or is greater than the secondary threshold value that the system was predetermine or the supernatant turbidity value is still greater than the one-level threshold value that the system was predetermine after the third settlement time, controls secondary treatment device (70) start, in order to by the supernatant of water distribution device (30) delivery carries out the preliminary treatment.

2. The water sample pretreatment device according to claim 1,

the water distribution device (30) comprises a water taking head (31) which is arranged in the water tank (10) and used for absorbing supernatant, the output end of the water taking head (31) is connected with a water taking hose (32), the output end of the water taking hose (32) is connected with a water distribution pipe (33), and the output end of the water distribution pipe (33) extends out of the water tank (10) and then is connected with the detection instrument (50) so as to distribute the supernatant into the detection instrument (50);

the water distribution pipe (33) is provided with a second pump transmitter (34) for pumping supernatant, a first filter (35) for filtering the supernatant, a second switch valve (36) for controlling the conduction or the separation of the water distribution pipe (33), a second adjusting valve (37) for adjusting the flow of the water distribution pipe (33), a water sample cup (38) for temporarily storing the supernatant, and a reversing valve (39) which is positioned at the downstream of the water sample cup (38) and is used for controlling the conduction or the separation of a pipeline between the water sample cup (38) and the detection instrument (50), wherein the second pump transmitter (34), the first filter (35), the second switch valve (36), the second adjusting valve (37) and the reversing valve (39) are respectively connected with the control device.

3. The water sample pretreatment device according to claim 2,

the turbidity detector (60) is connected to the water intake head (31) to detect a source water turbidity value of the source water at the water intake head (31) or a supernatant turbidity value of the supernatant;

the water distribution device (30) further comprises a lifting adjusting member (41) for adjusting the height of the water intake head (31), wherein the lifting adjusting member (41) comprises:

the lifting device comprises a lifting driver (411) connected to the outer surface of an upper cover of the water tank (10), a wire conveying rod (412) vertically arranged in the water tank (10) and fixedly connected with the driving end of the lifting driver (411), and a guide shaft rod (413) vertically arranged on the inner side wall of the water tank (10) and used for guiding the up-and-down movement of the water taking head (31), wherein the lifting driver (411) is connected with the control device;

the water intake head (31) respectively penetrates through the wire conveying rod (412) and the outer circle of the guide shaft rod (413), and the water intake head (31) is in threaded connection with the outer circle of the wire conveying rod (412).

4. The water sample pretreatment device according to claim 2,

the secondary treatment device (70) comprises a water conduit (71) for guiding supernatant, the input end of the water conduit (71) is communicated with the water sample cup (38), and the output end of the water conduit (71) is communicated with the reversing valve (39);

a second filter (72) for performing secondary filtration on the supernatant and a fixed containing bottle (73) for temporarily containing the filtered supernatant are arranged in a pipeline of the water conduit (71), and the second filter (72) is connected with the control device;

the volumetric flask (73) is communicated with a suction pipe (74), the suction end of the suction pipe (74) is connected with a suction pump (75) which is used for generating negative pressure in the water conduit (71) to suck supernatant, and the suction pump (75) is connected with the control device.

5. The water sample pretreatment device according to claim 4,

the water sample pretreatment device further comprises a system drainage device (80), wherein the system drainage device (80) comprises a drainage collecting pool, a first overflow pipe (81), a first sampling pipe (82), a second sampling pipe (83), a third sampling pipe (84), a second overflow pipe (85) and a fourth sampling pipe (86);

two ends of the first overflow pipe (81) are respectively communicated with the inner cavity side of the water tank (10) and the drainage collecting pool;

two ends of the first sample discharge pipe (82) are respectively communicated with the bottom of the inner cavity of the water tank (10) and the drainage collecting pool, and a third switch valve (87) used for conducting or cutting off the first sample discharge pipe (82) is arranged in a pipeline of the first sample discharge pipe (82);

two ends of the second sampling pipe (83) are respectively communicated with the first filter (35) and the drainage collecting pool, and a fourth switch valve (88) used for conducting or cutting off the second sampling pipe (83) is arranged in a pipeline of the second sampling pipe (83);

two ends of the third sample discharge pipe (84) are respectively communicated with the bottom of the inner cavity of the water sample cup (38) and the drainage collecting pool, and a pipeline of the third sample discharge pipe (84) is internally provided with a fifth switch valve (89) for connecting or disconnecting the third sample discharge pipe (84);

two ends of the second overflow pipe (85) are respectively communicated with the side wall of the water sample cup (38) and the drainage collecting pool;

two ends of the fourth sampling pipe (86) are respectively communicated with the bottom of the fixed-volume bottle (73) and the drainage collecting pool, and a pipeline of the fourth sampling pipe (86) is internally provided with a sixth switch valve (91) for connecting or disconnecting the fourth sampling pipe (86);

the third switch valve (87), the fourth switch valve (88), the fifth switch valve (89) and the sixth switch valve (91) are respectively connected with the control device.

6. The water sample pretreatment device according to claim 5,

the water sample pretreatment device further comprises a cleaning device (110), wherein the cleaning device (110) comprises a cleaning water supplier for supplying cleaning water, and the cleaning water supplier is connected with a water supply main pipe (111) and a first water supply branch pipe (112) and a second water supply branch pipe (113) which are respectively communicated with the water supply main pipe (111);

a fifth adjusting valve (114) for adjusting the flow of the water supply main pipe (111) is arranged in a pipeline of the water supply main pipe (111);

the output end of the first water supply branch pipe (112) is communicated with the source water input pipe (21), and an eighth switch valve (115) which leads the first water supply branch pipe (112) to be conducted or cut off is arranged in a pipeline of the first water supply branch pipe (112);

the output end of the second water supply branch pipe (113) is communicated with the water taking pipe, and a ninth switch valve (116) which leads the second water supply branch pipe (113) to be conducted or cut off is arranged in a pipeline of the second water supply branch pipe (113);

the washing water supplier, the fifth adjusting valve (114), the eighth switching valve (115), and the ninth switching valve (116) are connected to the control device, respectively.

7. The water sample pretreatment device according to claim 6,

the cleaning device (110) further comprises a third water supply branch pipe (117), the input end of the third water supply branch pipe (117) is communicated with the second water supply branch pipe (113), the output end of the third water supply branch pipe (117) extends into the water tank (10), a tenth switch valve (118) for controlling the third water supply branch pipe (117) to be conducted or cut off is arranged in a pipeline of the third water supply branch pipe (117), and the tenth switch valve (118) is connected with the control device;

the output end of the third water supply branch pipe (117) is communicated with a self-rotating spray head (119) which automatically rotates under the action of washing water pressure, and the self-rotating spray head (119) is communicated with a plurality of nozzles (120);

the water sample pretreatment device further comprises a reverse purging device (130), the reverse purging device (130) comprises an air purging pipe (131) communicated with the first sample discharging pipe (82), the input end of the air purging pipe (131) is communicated with a compressed air supply device used for supplying compressed air, an eleventh switch valve (132) used for controlling the conduction or the separation of the air purging pipe (131) and a third adjusting valve (133) used for adjusting the flow of the air purging pipe (131) are arranged in a pipeline of the air purging pipe (131), and the compressed air supply device, the eleventh switch valve (132) and the third adjusting valve (133) are respectively connected with the control device.

8. A water sample pretreatment system, characterized in that it comprises a water sample pretreatment device according to any one of claims 1 to 7, and a detection instrument (50) for detecting and analyzing the water sample treated by the water sample pretreatment device, wherein the detection instrument (50) is communicated with the output end of the water distribution device (30) of the water sample pretreatment device.

9. A water sample pretreatment method, which is carried out by using the water sample pretreatment system according to claim 8, and comprises the following steps:

s1: the control device controls the starting of the source water supply device (20) to supply source water into the water tank (10);

s2: the turbidity detector (60) detects the turbidity value of the source water, the control device correspondingly controls the water distribution device (30) to be started after different settling time according to different turbidity values, and when the turbidity value of the source water detected by the turbidity detector (60) is equal to or greater than a secondary threshold value preset by the system or the turbidity value of the supernatant is still greater than a primary threshold value preset by the system after third preset settling time, the control device controls the secondary treatment device to start to carry out pretreatment on the distributed supernatant so that the turbidity value of the supernatant distributed into the detection instrument (50) is equal to or less than the preset threshold value of the system.

10. The water sample pretreatment method according to claim 9, wherein the step S2 specifically comprises the following steps:

a turbidity detector (60) arranged in the water tank (10) detects the turbidity value of the source water, and when the turbidity value of the source water is equal to or less than a primary threshold value preset by the system, the control device controls the water distribution device (30) to be started after first preset settling time so as to distribute supernatant into the detection instrument (50);

when the turbidity value of the source water is larger than a primary threshold value preset by a system and smaller than a secondary threshold value preset by the system, the control device controls the water distribution device (30) to be started after second preset settling time so as to distribute the supernatant into the detection instrument (50);

when the turbidity value of the source water is greater than a primary threshold value preset by the system, the control device controls the water distribution device (30) to be started when the turbidity value of the supernatant is equal to or less than the primary threshold value preset by the system within a third preset settling time so as to distribute the supernatant into the detection instrument (50);

when the turbidity value of the source water detected by the turbidity detector (60) is equal to or greater than a secondary threshold value preset by the system or the turbidity value of the supernatant after a third preset settling time is still greater than a primary threshold value preset by the system, the control device controls the secondary treatment device (70) to be started so as to filter, centrifuge or dilute the supernatant delivered by the water distribution device (30).