CN114593952A

CN114593952A - Water body micro-plastic collecting device and three-dimensional collecting system

Info

Publication number: CN114593952A
Application number: CN202210491058.5A
Authority: CN
Inventors: 罗维; 赵品; 姜宁
Original assignee: Research Center for Eco Environmental Sciences of CAS
Current assignee: Research Center for Eco Environmental Sciences of CAS
Priority date: 2022-05-07
Filing date: 2022-05-07
Publication date: 2022-06-07
Anticipated expiration: 2042-05-07
Also published as: CN114593952B

Abstract

The application belongs to the environmental monitoring equipment field, concretely relates to little plastics collection system of water, including the acquisition unit, the acquisition unit includes: a sample introduction box; the filter device comprises a filter screen and a collecting pipe connected with the tail part of the filter screen; the net head fixing piece is used for connecting the outlet of the sample inlet box and the head part of the filter screen; the net port opening and closing control assembly is arranged on the sampling box, is connected with the net head fixing piece and is used for controlling the net port of the filtering device to be closed; and the trawl control component is in communication connection with the net port opening and closing control component and controls the operation of the net port opening and closing control component after receiving the instruction. Still provide a three-dimensional collection system of water body micro-plastic, including the above-mentioned collection system of multiunit that connects gradually along the water depth direction. Through controlling the opening and closing of the net port of the filter, a water sample is not collected before the net port reaches the specified depth, the net port is directly closed to stop filtering after sampling is finished, filtering time nodes can be accurately controlled, sample loss in the filter in the process of collecting and releasing the equipment is avoided, and data reliability and accuracy are guaranteed.

Description

Water body micro-plastic collecting device and three-dimensional collecting system

Technical Field

The application relates to the technical field of water environment monitoring equipment, in particular to a water body micro-plastic collecting device and a three-dimensional collecting system, which are applicable to multistage synchronous automatic collection of micro-plastics in different depths of water bodies such as static and low-flow-rate lakes and reservoirs, rivers, estuaries, sea areas and the like.

Background

The micro plastic with the particle size less than 5 mm is a new pollutant which is highly concerned at home and abroad in recent years, can enter water environment through various ways, and poses serious threats to aquatic organisms, ecological systems and even human health. Because the micro-plastics are widely distributed in the global scope, the environmental behaviors, tendency and influence are quite complex, and the comprehensive investigation and research on the abundance and the characteristics of the micro-plastics in fresh water and marine ecosystems, particularly in low-flow-rate lake and reservoir, rivers, estuary and sea water with serious pollution is urgently needed. The investigation of environmental micro-plastic pollution began in 1971 with the first collection of micro-plastic particles from remote waters using a Neuston trawl net, from which time researchers mostly collected micro-plastic debris using a method similar to the Neuston trawl net collection method. Despite the fact that research on microplastics has been carried out for nearly two decades, the sample collection methods have not been standardized and standardized to date. Due to the diversity of physical and chemical properties of the micro-plastics and the complexity of the environment matrix, the collection of the micro-plastics in the water environment is still a technical problem to be overcome. The key of the research on the problem of the micro-plastic in the water environment is to obtain a representative micro-plastic sample, and innovative and creative sampling tools and monitoring systems can greatly improve the precision of the analysis and the test of the micro-plastic in the water environment and provide scientific and reliable data support for the evaluation of the pollution and the risk of the micro-plastic.

The trawl is the water environment micro-plastic collection device which is the earliest and most widely applied and is easy to operate, a sampling filter screen is continuously towed on the water surface for 30-60 minutes at the speed of 2-4 knots by a ship, a large amount of water samples are rapidly filtered by the filter screen in the towing process, and the micro-plastic is directly concentrated in the sampling process. The filter mesh filtration pore size is generally 50-3000 microns, the most common pore size is 300-333 microns, and the surface water sampling is generally a Manta mesh and a Neuston mesh with the pore size of 50-500 microns. The water column was sampled vertically using a Plankton mesh or a Bongo mesh with a smaller pore size. For sampling of water bodies on river beds or sea beds, micro-plastics are collected using suspended nets or benthic nets anchored to the river/sea bed. Trawl sampling is capable of filtering and collecting micro-plastics in large volume water samples in a larger sampling region, and is more representative than small volume sampling methods in view of the high variability of regional micro-plastics. However, the conventional trawl sampling method has the following disadvantages: while the pore size of the screens used in trawl sampling limits the size of the micro-plastic particles collected, the main limitation of conventional trawl technology is the difficulty in collecting micro-plastics smaller than 300 microns, resulting in underestimating the concentration of smaller micro-plastics in the water. In addition, plankton and algae which multiply in large quantities in the water body can block the small-mesh filter screen, and the sampling efficiency is reduced. And (II) the traditional trawl is mainly used for oceans and large rivers, generally needs ships to provide towing power, and is difficult to realize micro-plastic sampling due to the lack of a towing device. And thirdly, in order to avoid the influence of water body stirring on sampling caused by dragging devices such as the ship body in the advancing process, the trawlnet needs to be arranged on two sides of the ship and at a certain distance from the ship body or at a long distance behind the ship, so that great inconvenience is brought to sampling operation. And (IV) the traditional trawl is difficult to be suitable for narrow water bodies, such as small water bodies of ponds, depressions and the like, small urban rivers or rivers with obstacles. And (V) the traditional trawl is only limited to sampling of surface water body, but cannot perform three-dimensional space multilayer synchronous sampling on micro plastic in a water column in the vertical direction of a deep water area. Although the Plankton web or the Bongo web can sample in the vertical direction, it cannot simultaneously sample micro-plastics of different depths, and requires a dragging device, and thus is susceptible to the influence of ship speed and water flow. (VI) the traditional trawl sampling filter screen port is in a normally open state, and the screen port can not be closed in time before the sampling begins and when the sampling ends, so that the volume error of a filtered water sample and the loss of micro-plastic are caused, and the sampling precision of the micro-plastic is influenced.

Based on the problems, a novel micro-plastic collecting device in an underwater environment is urgently needed to be creatively researched and developed, so that the micro-plastic collecting device can be better served for collecting and monitoring micro-plastics of a water environment, particularly a low-flow-rate water body, and comprehensive, accurate and reliable monitoring data can be provided for protecting and treating the water ecological environment.

Disclosure of Invention

The following presents a simplified summary of the application in order to provide a basic understanding of some aspects of the application. It should be understood that this summary is not an exhaustive overview of the present application. It is not intended to identify key or critical elements of the application or to delineate the scope of the application. Its sole purpose is to present some concepts in a simplified form as a prelude to the more detailed description that is discussed later.

In view of the above-mentioned defects of the prior art, one of the objectives of the present application is to provide a water micro-plastic collecting device, so as to at least solve the problem of poor data reliability and accuracy caused by the current inability to precisely control the filtering process node and the filtering volume.

According to one aspect of the application, a water body micro-plastic collecting device is provided, which comprises a collecting unit, wherein the collecting unit comprises: a sample introduction box; the filter device comprises a filter screen and a collecting pipe connected with the tail part of the filter screen; the net head fixing piece is used for connecting the outlet of the sample inlet box and the head part of the filter screen; the net port opening and closing control assembly is arranged on the sampling box, is connected with the net head fixing piece and is used for controlling the net port of the filtering device to be closed; and the trawl control component is in communication connection with the net port opening and closing control component and controls the operation of the net port opening and closing control component after receiving the instruction.

According to another aspect of the application, a three-dimensional collection system for water body micro-plastic is provided, which comprises a plurality of groups of the above water body micro-plastic sample collection devices connected in sequence along the depth direction of a water body.

Compared with the prior art, the invention has the beneficial effects that:

1. the water body micro-plastic collecting device provided by the invention can control the opening and closing of the net port of the filter, water samples are not collected before the net port reaches the specified depth, and the net port is directly closed to stop filtering after sampling is finished, so that the nodes of the filtering process are accurately controlled, the accuracy of the filtering volume is ensured, the loss of samples in the filter in the process of collecting and releasing equipment can be avoided, and the reliability and the accuracy of data are ensured.

2. The water body micro-plastic collecting device provided by the invention is powered by the propeller, is remotely controlled by a wireless way on a ship or on a shore, is warned by the ultrasonic sensor to avoid obstacles, collects water samples in a full-automatic way, and is more flexible and intelligent in sampling.

3. The depth regulation and control system of the water body micro-plastic acquisition device comprises a ballast water tank, a small self-priming pump and a compressed gas tank, wherein according to real-time depth data, gas injection and drainage of the ballast water tank are carried out to increase buoyancy or gas discharge and water inlet of the ballast water tank are carried out to increase gravity, so that real-time floating and submerging in the vertical direction are realized, and different sampling depth requirements can be met.

4. The water body micro-plastic three-dimensional acquisition system provided by the invention can realize simultaneous acquisition of multiple water layers, the vertical distance between acquisition devices is adjusted by using the adjustable inter-group connection system, the vertical distance between sampling water layers can be accurately changed, the buoyancy and gravity can be adjusted according to requirements to accurately control the sampling depth, and the three-dimensional sampling of micro-plastic in a flowing water environment is realized.

5. The acquisition unit and the multi-parameter synchronous monitoring system of the water body micro-plastic acquisition device provided by the invention are respectively provided with two groups of parallel acquisition and monitoring, two repeated parallel samples can be directly obtained by one-time acquisition and filtration, and the quality control is more scientific and reliable.

6. The device and the system provided by the invention have good reliability, portability and expansibility, are suitable for sampling the micro-plastics on the water surface and under the water of a non-sampling ship, have the best effect on the low-flow-rate water body, and provide innovative technical support for the new field and new situation of novel pollutant monitoring of the water environment in China.

7. The invention provides a water body three-dimensional full-automatic micro-plastic acquisition and multi-parameter synchronous monitoring system with combined opening and closing type multi-stage filter screens, which is suitable for multi-stage synchronous automatic acquisition of micro-plastics at different depths of water bodies of lakes and reservoirs, rivers, estuaries, sea areas and the like at static and low flow rates and synchronous monitoring of related water parameters.

Drawings

The present application may be better understood by reference to the following description taken in conjunction with the accompanying drawings, in which like or similar reference numerals are used throughout the figures to designate like or similar components. The accompanying drawings, which are incorporated in and form a part of this specification, illustrate preferred embodiments of the present application and, together with the detailed description, serve to further explain the principles and advantages of the application. Wherein:

FIG. 1 is a perspective view of a single set of sample collection devices according to a preferred embodiment of the present invention;

fig. 2 is a schematic structural diagram of an opening and closing state of the net port opening and closing control assembly according to a preferred embodiment of the present invention, in which (a) is a schematic side view of a net port closing state, (b) is a schematic side view of a net port opening state, (c) is a schematic front view of a net port closing state, and (d) is a schematic front view of a net port opening state;

fig. 3 is a schematic structural diagram of an open/close state of a net port open/close control assembly according to another two preferred embodiments of the present invention, wherein (a) and (b) are schematic side views of a closed/open state of a net port according to one embodiment, respectively, and (c) and (d) are schematic side views of a closed/open state of a net port according to another embodiment, respectively;

fig. 4 is a schematic structural diagram of an open/close state of a net port open/close control assembly according to another preferred embodiment of the present invention, wherein (a) is a schematic side view of a closed state of a net port, and (b) is a schematic side view of an open state of the net port;

fig. 5 is a detailed schematic view of the net port opening and closing control assembly shown in fig. 4, wherein (a) is a schematic side view of a closed state of the net port, and (b) is a schematic side view of an opened state of the net port;

FIG. 6 is a schematic front structural view of a water body three-dimensional fully-automatic micro-plastic collection and multi-parameter synchronous monitoring system with combined open-close type multi-stage filter screens according to a preferred embodiment of the present invention;

FIG. 7 is a schematic side view of a multi-layered sample acquisition system using an adjustable angle hinge connection according to a preferred embodiment of the present invention;

FIG. 8 is a schematic view of the adjustable angle hinge connection of the embodiment of FIG. 7;

FIG. 9 is a schematic structural view of a multi-layered sample acquisition system using a detachable, telescoping metal rod connection in accordance with a preferred embodiment of the present invention;

the reference numbers in the figures are as follows:

1-a remote control system;

2-trawl control component;

3-a collecting unit;

31-a sample introduction box;

33-net head fixing part;

32-a filtration device; 321-a first filter screen, 322-a second filter screen, 323-a third filter screen, 324-a first collecting pipe, 325-a second collecting pipe, 326-a third collecting pipe, 327-a connecting rope, 328-a cable and 329-a supporting rod;

33-net head fixing piece, 331-first pin, 332-hanging ring;

34-a net port opening and closing control component; 341-stepper motor, 342-first fixed pulley, 343-second fixed pulley, 344-movable pulley, 345-slide rail, 346-traction rope, 347-drive gear, 348-driven track, 3481-toothed belt, 3482-towing part, 349-slider, 350-crank mechanism;

4-a water ballast tank, 5-a battery pack, 6-a self-priming pump, 7-a compressed gas tank, 8-a propeller thruster and 9-a protective cover;

10-a volumetric sampling assembly;

111-connecting rod, 112-threaded connecting piece, 113-acute angle supporting hinge, 114-obtuse angle supporting hinge, 115-connecting shaft, 116-hinge fixing base, 117-second pin, 118-hinge supporting rod, 1191-gear and 1192-gear groove;

311-inductor connecting rod, 312-ultrasonic obstacle avoidance sensor, 313-depth-temperature-conductivity multi-parameter sensor, 314-mesh mouth flow meter;

12-sampler handle.

It should be understood by those skilled in the art that the same reference numerals represent the same parts or equivalent parts, and all the figures are only for convenience of explaining the technical contents of the present invention, and the numbers used for constituting the preferred embodiments, the positions of the parts, the mutual relations among the parts, the sizes of the parts, and other technical features do not constitute limitations on the technical solution itself, but extend to the whole field covered by the technical field. Elements, components and parts of the drawings are illustrated for simplicity and clarity and have not necessarily been drawn to scale; for example, the dimensions of some of the elements and components in the figures may be exaggerated relative to other elements and components to help improve the understanding of the embodiments of the present application.

Detailed Description

Exemplary embodiments of the present application will be described hereinafter with reference to the accompanying drawings. In the interest of clarity and conciseness, not all features of an actual implementation are described in the specification. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with device-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.

Here, it should be further noted that, in order to avoid obscuring the present application with unnecessary details, only the device structures and/or processing steps closely related to the aspects of the present application are shown in the drawings, and other details not so relevant to the present application are omitted.

The embodiment of the application provides a water body micro-plastic collecting device which comprises a sampling unit, wherein the sampling unit comprises a sampling box, a filtering device, a net head fixing part and a net port opening and closing control assembly; wherein, the export of advancing the appearance case passes through net head mounting and filter equipment's entry linkage, net gape switching control assembly set up in on the appearance case advances, with net head mounting is connected for control filter equipment's net gape switching.

It should be noted that in the present application, "a and/or B" should be interpreted as any of the following three cases in parallel: a; b; a and B. For example, "sensor and/or locator" should be understood to mean any of "sensor," locator, "and" sensor and locator.

Fig. 1-2 schematically show an example structure of a water body micro-plastic collecting device according to an embodiment of the present application.

As shown in fig. 1-2, the device for collecting micro-plastics in a water body according to the embodiment of the present application includes a collecting unit 3, where the collecting unit 3 includes:

a sample introduction box 31;

the filtering device 32 comprises a filter screen and a collecting pipe connected with the tail part of the filter screen;

a screen head fixing member 33 for connecting the outlet of the sample introduction box 31 and the head of the screen;

a net opening/closing control assembly 34, which is arranged on the sample injection box 31, connected with the net head fixing member 33, and used for controlling the opening/closing of the net opening of the filtering device 32;

the trawl control part 2 is in communication connection with the net mouth opening and closing control component 34, and controls the operation of the net mouth opening and closing control component 34 after receiving the instruction. The various components and their connections are further described below.

In the embodiment of the present application, the sample introduction box 31 is a hollow body provided with a through channel, which may be a square body, a cylindrical body, etc., the through channel is a sample introduction channel, and when the collection device works, water flows in from an inlet of the sample introduction channel, flows out from an outlet thereof, and enters the following filtering device 32; the through channel itself may also be a square, cylinder, etc., generally in line with the sample chamber 31.

In a specific example, the sample introduction box 31 may be a rectangular aluminum alloy metal frame with a two-way opening.

In the embodiment of the present application, the filtering device 32 includes a filter screen and a collecting pipe, and the collecting pipe is disposed at the tail of the filter screen and connected to the tail of the filter screen; the head of the filter screen is connected with the sample injection box 31 through a screen head fixing piece 33. Typically, the filter screen has openings at both ends, and is designed in a tapered gradual manner (a pyramid shape or a cone shape depending on the shape of the opening at the head), and the size of the opening at the first end, i.e., the head, is larger than the size of the opening at the second end, i.e., the tail. The second end, namely the opening at the tail part, can be connected with the collecting pipe through a detachable threaded connector, and can also be connected in other modes. The collection tube collects the micro plastic trapped by the screen.

In the preferred embodiment, the filter assembly 32 further includes a support bar 329 and a cable 328; one end of the support bar 329 is connected with the net head fixing piece 33, and the other end is connected with the cable 328; the cable 328 is connected at one end to the support bar 329 and at the other end to the collection tube of the filter. Illustratively, the support bar 329 is substantially equal to the filtering device 32 in length (approximately the total length of the filtering screen and the collecting pipe), and may be made of metal, one end of the support bar 329 is detachably connected to the upper end of the head fixing member 33 through a screw thread, and the other end is connected to the tail end of the collecting pipe of the filtering device 32 through a cable 328, so as to ensure that the filtering device 32 keeps a normal conical state during sampling, and prevent the rear end of the filtering screen from falling and folding, which results in reduced collecting efficiency.

In a preferred embodiment, the filtering device 32 is a multi-stage filter, such as a two-stage filter, a three-stage filter, a four-stage filter, a five-stage filter, etc., the filtering net head of each stage of filter is connected to the sample feeding box 31 through the net head fixing member 33, and the filtering net hole diameter of each stage of filter decreases from inside to outside in sequence according to the increase of stages; preferably, in order to maintain a good screen shape when the collecting apparatus is operated, the collecting pipes connected to the screen tails of the filters of each stage may be sequentially connected by the connection rope 327.

In the preferred embodiment described above, the filter apparatus 32 further includes a support assembly for supporting the multi-stage filter, the support assembly including a support bar 329 and a cable 328; one end of the support bar 329 is connected with the net head fixing piece 33, and the other end is connected with the cable 328; the cable 328 is connected at one end to the support bar 329 and at the other end to the collection tube of the last stage filter. In the preferred embodiment, the supporting rod 329 is substantially as long as the last filter, one end of the supporting rod 329 is detachably connected with the upper end of the net head fixing piece 33 through threads, and the other end of the supporting rod 329 is connected with the tail end of the collecting pipe of the last filter through the cable 328, so that the multi-stage filter is kept in a normal pyramid shape in the sampling process, and the phenomenon that the rear end of the filter screen is dropped and folded to cause the reduction of the collecting efficiency is avoided. Through field verification, the filter without the support component completely depends on the water flow scouring force to keep the pyramid state, so that the filtering flow rate cannot be too small, and in a field water body environment, particularly a low-flow-rate environment, large power needs to be provided to keep high-flow-rate filtering, the load of equipment is increased, and the stability of the equipment is reduced due to too high flow rate. When the velocity of flow is less, the trawl net latter half can drop under the action of gravity, and the folding effective filtering surface of loss of back half filter screen lacks the pyramid state, and little plastics that the filter screen front end was held back also can not be collected into in the less collecting tube of tail end by rivers erode, finally leads to filtration efficiency to descend.

More preferably, in the embodiment of the present application, in consideration of the economical efficiency and easy operation of the apparatus, the filtering device 32 is a three-stage filter including a first strainer 321 and a first collecting pipe 324 connected to a rear portion thereof, a second stage filter including a second strainer 322 and a second collecting pipe 325 connected to a rear portion thereof, and a third stage filter including a third strainer 323 and a third collecting pipe 326 connected to a rear portion thereof; the first collecting pipe 324, the second collecting pipe 325 and the third collecting pipe 326 are connected in sequence through a connecting rope 327.

In a specific example, the filter mesh of the first stage filter is 5 mm in filter pore size, the current micro plastic research focuses on plastic particles below 5 mm, the plastic particles larger than 5 mm are regarded as conventional plastic or bulk plastic, and the conventional plastic fragments provide reference for the source analysis of the micro plastic, so that the first stage filter mainly collects the plastic particles larger than 5 mm in particle size, and simultaneously retains bulk impurities to reduce the pressure of the next stage filter; the outer side of the first stage filter is provided with a second stage filter, the filtering pore diameter of a filter screen is 1 mm, 1 mm is mostly used as a boundary line between a large particle diameter and a small particle diameter of the micro-plastic in the previous research on the micro-plastic of the water body, and the second stage filter is mainly used for filtering and collecting micro-plastic particles with large particle diameter (1-5 mm); the second level filter outside is equipped with the third level filter, and filter screen filtration aperture is 0.05 millimeter, and the minimum size that can collect little plastics has been decided to third level filter mesh aperture size, and little plastics particle diameter in the water is the smaller accounts for than generally higher, and the too big component information that can lose little plastics part of third level filter mesh aperture, but the aperture undersize also can cause the quick jam of filter screen, and the filtration can not go on. Through the verification of field sampling work, in order to avoid rapid blockage caused by too small pore size of the filter screen, the minimum pore size of the filter screen of the final stage filter can be set to be 0.05 mm.

In the embodiment of the present application, a net head fixing member 33 is used for connecting the outlet of the sample inlet box 31 and the head of the filter net; the net head fixing piece 33 is a hard rectangular frame, the material of the net head fixing piece can be metal, and the size of the net head fixing piece is basically the same as that of the outlet of the sample injection box 31. The bottom edge of the net head fixing piece 33 is fixedly connected with the bottom edge of the outlet of the sample injection box 31 in a welding, clamping and other connecting mode. Two sides of the net head fixing member 33 are respectively composed of two rods with substantially equal length, first ends of the two rods are connected through a first pin 331, second ends of the two rods are connected through a spring (not shown in fig. 2, for example, a spiral spring can be adopted), and the two rods can rotate to a certain angle by taking the first pin 331 as a pivot under the driving of external power to drive the top edge of the net head fixing member 33 to move up and down, so that the opening and closing of the net head of the filter screen are realized.

Optionally, two side edges of the net head fixing piece 33 are respectively formed by connecting two sections of rods with substantially equal length, first ends of the two rods are connected through a torsion spring, second ends of the two sections of rods are respectively connected with the bottom edge and the top edge of the net head fixing piece 33, and the two sections of rods can rotate to a certain angle by taking the torsion spring as a pivot under the driving of external power (such as a motor) to drive the top edge of the net head fixing piece 33 to move up and down, so that the opening and closing of the net head of the filter screen are realized.

The head mount 33 is preferably removably attached to the head of the screen. Illustratively, a zipper strip is fixedly arranged along the circumferential direction of the net head fixing piece 33 through a rivet, a first end (net head end) opening of a filter screen of the multi-stage filter is provided with a matched zipper strip along the circumferential direction, the multi-stage filter is detachably arranged on the net head fixing piece 33 through the zipper strip, and when the net head fixing piece 33 is completely opened, a structure enclosed with an outlet of the sample injection box 31 is formed.

In the embodiment of the present application, the opening and closing control component 34 is disposed on the sampling box 31, and is connected to the net head fixing component 33 for controlling the opening and closing of the screen opening of the filter screen. Referring to fig. 2, the gateway opening and closing control assembly 34 includes a stepping motor 341, a pulling rope 346, a movable pulley 344, a first fixed pulley 342, a second fixed pulley 343, and a slide rail 345; the first fixed pulley 342 and the second fixed pulley 343 are respectively disposed on two sides of the top of the sidewall of the sample injection box 31, a slide rail 345 is disposed between the first fixed pulley 342 and the second fixed pulley 343, a movable pulley 344 is disposed on the slide rail 345, one end of a traction rope 346 (which may be a steel wire rope) is connected to the top of the net head fixing member 33 (for example, but not limited thereto, the traction rope is connected to the suspension ring 332 disposed on the top edge of the net head fixing member 33), and the other end of the traction rope 346 is connected to the second fixed pulley 343 through the first fixed pulley 342, the movable pulley 344 and the second fixed pulley 343 in sequence; the stepping motor 341 is connected with the movable pulley 344 through a crank mechanism, and the movable pulley 344 is driven by the power of the stepping motor 341 to move up and down along the slide rail 345, so as to pull the traction rope 346 to move, thereby realizing the state conversion of closing and opening of the screen opening. In one embodiment, the stepping motor 341 may be a small stepping motor disposed on the sidewall of the sample box 31, and the first fixed pulley 342, the second fixed pulley 343, and the slide rail 345 may also be disposed on the sidewall of the sample box 31. The stepping motor is a motor which converts an electric pulse signal into corresponding angular displacement or linear displacement, the angular displacement of the stepping motor is strictly proportional to the number of input pulses, is synchronous with the pulses in time, can quickly respond, and adopts a small stepping motor according to the requirements of an acquisition device.

Specifically, the stepping motor 341 controls the movable pulley 344 to move up and down on the sliding rail 345 under the instruction of the trawl control part 2, and the pulling rope 346 on the pulley drives the string head fixing part 33 to complete the closing and opening actions. When the movable pulley 344 moves to the highest point of the sliding rail 345, the pull rope 346 is connected with the top of the net head fixing piece 33 and is released downwards, the spring located at the side edge of the net head fixing piece 33 and connected with the second ends of the two sections of rods contracts, because each vertical rod of the net head fixing piece 33 is connected with two sections of metal rods with equal length through the first pin 331, the two sections of metal rods rotate by taking the first pin 331 as a pivot and are gradually folded inwards, finally, the included angle between the two sections of metal rods is minimum, the net port of the filter is completely closed, the filter is basically separated from the outlet of the sample injection box 31, and the filter is in a non-working state. When the movable pulley 344 moves to the lowest point of the sliding rail 345, the traction rope 346 pulls the top of the screen head fixing part 33 upwards, the spring between the two sections of rods on the side of the screen head fixing part 33 is stretched, the two sections of metal rods are gradually opened and separated, finally the two sections of metal rods are completely opened to 180 degrees, the screen port of the filter is completely opened and is enclosed with the outlet of the sample injection box 31, and the filter is in a filtering working state.

In another embodiment of the present application, referring to fig. 3, the net head fixing member 33 includes a hard bottom edge, a hard top edge, and a flexible side edge, which is opened to match the shape and size of the outlet of the sample injection box 31. The bottom edge of the net head fixing piece 33 is fixedly connected with the bottom edge of the outlet of the sample injection box 31 in a welding, clamping and other modes. At least one end of the top side of the net head fixing member 33 is provided with a connecting member, such as a hook, for connecting with the net opening/closing control unit 34. The two ends of the side of the net head fixing member 33 are connected by an elastic member (not shown in fig. 3), which is a resilient cord or a spring (e.g., a spiral spring). The four sides of the head fixture 33 are connected to the screen head of the filtering device 32.

In another embodiment, referring to (a) and (b) of fig. 3, the portal opening and closing control assembly 34 includes a stepping motor 341, a pulling rope 346, a sliding block 349, a first fixed pulley 342, and a sliding rail 345, wherein the first fixed pulley 342 is disposed on the top of the sidewall of the sampling box 31, the sliding rail 345 is disposed at a position where the sampling box 31 and the lateral side of the web head fixing member 33 are substantially overlapped, and the sliding block 349 is disposed on the sliding rail 345 and is connected to the top side of the web head fixing member 33 during use; one end of the traction rope 346 is connected with the slider 349, and the other end is connected with the stepping motor 341 through the first fixed pulley 342 in sequence; when the screen head fixing piece 33 works, the pulling rope 346 is driven to move by the power of the stepping motor 341 and the elastic piece on the side edge of the screen head fixing piece 33, so that the sliding block 349 is driven to move up and down along the sliding rail 345, the top edge of the screen head fixing piece 33 is further driven to move up and down, and the state conversion of opening and closing of a screen opening of a filter screen is realized.

In another embodiment of the present application, referring to fig. 3, the net head fixing member 33 includes a hard bottom edge, a hard top edge, and a flexible side edge, which is opened to match the shape and size of the outlet of the sample introduction tank 31. The bottom edge of the net head fixing piece 33 is fixedly connected with the bottom edge of the outlet of the sample injection box 31 in a welding, clamping and other connecting mode. At least one end of the top side of the net head fixing member 33 is provided with a connecting member, such as a hook, for connecting with the net opening/closing control unit 34. Four sides of the head fixing member 33 are connected to the screen head of the filtering apparatus 32. Referring to (c) and (d) of fig. 3, the net opening/closing control assembly 34 includes a stepping motor 341, a crank mechanism 350, a slider 349 and a slide rail 345, wherein the slide rail 345 is disposed at a position where the side edges of the sampling box 31 and the net head fixing member 33 are substantially overlapped when being opened, and the slider 349 is disposed on the slide rail 345 and is connected to the top edge of the net head fixing member 33 when in use; one end of the crank mechanism 350 is connected to the slider 349, and the other end is connected to the stepping motor 341; during operation, the slider 349 is controlled by the power of the stepping motor 341 to move up and down along the slide rail 345, so as to move the top edge of the net head fixing member 33 up and down, and realize the state conversion between the opening and closing of the screen port.

In yet another embodiment of the present application, referring to fig. 4 and 5, the net head fixing member 33 includes a hard bottom edge, a hard top edge, and a flexible side edge, which is opened to match the shape and size of the outlet of the sample introduction tank 31. The bottom edge of the net head fixing piece 33 is fixedly connected with the bottom edge of the outlet of the sample injection box 31 in a welding, clamping and other connecting mode. At least one end of the top side of the net head fixing member 33 is provided with a connecting member, such as a hook, for connecting with the net opening/closing control unit 34. The sides of the net head fixing member 33 are flexible members such as ropes. The four sides of the head fixture 33 are connected to the screen head of the filtering device 32.

In the above still another embodiment, the net port opening and closing control unit 34 includes the stepping motor 341, the transmission gear 347, the driven crawler 348; wherein, the driven caterpillar 348 comprises a towing component 3482 and a rack belt 3481 sleeved on the periphery of the towing component 3482; the towing part 3482 is fixed on the side wall of the sample injection box 31, and the height of the towing part 3482 is equivalent to that of the sample injection box 31; one end of the rack belt 3481 is provided with a connecting piece for connecting with the top edge of the net head fixing piece 33, the rack belt 3481 is meshed with the transmission gear 347, and the transmission gear 347 is connected with the stepping motor 341; when the device works, the transmission gear 347 moves through the power of the stepping motor 341, so that the rack belt 3481 is driven to move up and down, the top edge of the net head fixing piece 33 moves up and down, and the state conversion of opening and closing of the net opening of the filter screen is realized. Specifically, the transmission gear 347 is mounted on the rotor of the stepping motor 341, and the stepping motor 341 outputs high and low levels to the direction end of the driver to change the stepping rotation direction by adopting a pulse direction adding control mode. The stepping motor 341 and the driven crawler 348 are mounted on the sampling box 31. The stepping motor 341 drives the transmission gear 347 to rotate clockwise, the rack belt 3481 of the driven crawler belt 348 moves anticlockwise, the top edge of the net head fixing piece 33 is driven to gradually rise to the top point, and the net opening is completely opened; the output level of the driver direction end of the stepping motor 341 is changed, the stepping motor 341 drives the transmission gear 347 to rotate anticlockwise, the rack belt 3481 moves clockwise, the top edge of the net head fixing piece 33 is driven to gradually descend to the bottom end, and the net opening is completely closed.

The state of filter work/closing has been controlled through the net gape switching control subassembly that this application provided. The inventor finds that: in the initial version of the invention, due to the lack of the component, after the sampler is placed on a sampling point, the net port is always in an open state, and before the system does not start to operate stably, part of water sample enters the filter with the open net port under the action of natural water flow, so that error occurs in volume calculation of the filtered water sample. In addition, in the process from the end of sampling to the complete separation of the sampling device from the water surface, the net port cannot be closed, and the micro plastic trapped in the filter or even the collecting tube can be flushed by natural water flow in the opposite direction, so that the micro plastic loss is caused, and the micro plastic in the filter or the collecting tube is filtered, concentrated and collected by a large volume of water sample after the sampling is finished, so that the final analysis result can be greatly wrong even if a small amount of micro plastic is lost. In addition, according to the inventor, the method finds out in the practice of sampling small rivers, estuaries, high-altitude lakes and inland reservoirs in coastal zones: when the water depth cannot meet the sampling requirement or an obstacle which cannot be bypassed exists underwater, even when the hydraulic stirring is too large and the sampling is required to be temporarily stopped, the sampling of the sampler and the recovery device must be stopped in time. The utility model provides a net gape switching control subassembly can in time close the introduction port, suspends the sampling, then the device come-up takes out from the aquatic temporarily, when reacing suitable position again with sampling device launch, opens filter net gape through net gape switching control subassembly and continues the sampling, and the sampling process is controllable completely, can deal with complicated sampling environment in a flexible way.

In the embodiment of the application, the water body micro-plastic collection device further comprises a fixed-volume sampling assembly 10, which comprises water collectors arranged on two sides of the sampling box 31 in pairs, for example, 1L cover-type water collectors symmetrically fixed on two sides of the sampling box 31, and is used for collecting 1L water samples on a water layer at a specific depth, analyzing water quality parameters of the water layer, and conveniently explaining water quality factors influencing micro-plastic distribution. The water quality parameter of the micro-plastic sampling water layer is important for micro-plastic research, and the inventor finds that some problems exist if 1L water sample collection and micro-plastic filtration collection are separately carried out in the actual sampling process: gather 1L water sample at different water layers and be more difficult, need use powerful suction pump just can extract the sample bottle with the water in the deep water layer, can't guarantee moreover that the drinking-water pipe water inlet degree of depth keeps the complete unanimity with little plastics collection water layer. In the embodiment of this application, with 1L water sample collector snap-on little plastic collection system, both go on in step, are in the same environment completely, operate simpler, and data are accurate more reasonable.

In the embodiment of this application, the little plastics collection system of water still includes: the motion control assembly comprises a depth regulating assembly and a propelling assembly, the depth regulating assembly controls the floating and submerging of the collecting device in the vertical direction, and the propelling assembly controls the collecting device to move back and forth and left and right on the horizontal plane; see fig. 1 and 6.

The depth control assembly, as shown in fig. 1 and 6, is symmetrically arranged on a pair of sidewalls of the sampling box 31 perpendicular to the water surface in a wing shape; the depth regulation and control assembly comprises a ballast water tank 4, a self-priming pump 6, a compressed gas tank 7 and a battery pack 5; ballast water tank 4, self priming pump 6, compressed gas jar 7 set gradually and connect according to keeping away from the direction of advancing appearance case 31 gradually, still including setting up in its outside be used for waterproof protection casing 9. More specifically, ballast water tank 4, self-priming pump 6, compressed gas tank 7 are installed in protection casing 9 after fixed through welding, and self-priming pump 6 is set up in the middle of ballast water tank 4 and compressed gas tank 7 to control the business turn over of the gas of ballast water tank 4/give vent to anger, drainage/intaking to and compressed gas tank 7 is interior. The depth control component forms an acute included angle (for example, 75 degrees) with the axis of the inlet and outlet directions of the sample injection box 31, so that water flow can smoothly flow through the depth control component.

Illustratively, in the depth control assembly, a vent (serving as both an air inlet and an air outlet) is provided at an upper portion of ballast tank 4, and the vent is connected to an air inlet and an air outlet of self-priming pump 6 respectively through pipes, and self-priming pump 6 is connected to a vent (serving as both an air inlet and an air outlet) of compressed air tank 7 through a pipe. The following switching between the first state and the second state can be realized through the electromagnetic valve arranged on the pipeline. The first state: air inlet (blow vent) of ballast water tank 4 are connected to self priming pump 6's gas vent, and compressed gas jar 7's gas vent (blow vent) are connected to self priming pump 6's gas inlet, and the gas in the compressed gas jar 7 is transmitted to ballast water tank 4, buoyancy increase, device come-up by self priming pump 6. And a second state: the gas outlet of ballast water tank 4 is connected to air inlet (blow vent) of self priming pump 6, and air inlet (blow vent) of compressed gas jar 7 is connected to the gas outlet of self priming pump 6, and the gas in ballast water tank 4 is transmitted to compressed gas jar 7 by self priming pump 6, and buoyancy reduces, the device dives down. The lower part of the ballast water tank 4 is provided with a water inlet and a water outlet (the two can be respectively arranged or can be the same opening), when the ballast water tank is in a state I, the gas in the compressed gas tank 7 enters the ballast water tank 4, the water in the ballast water tank 4 is discharged through the water outlet under the pressure, the weight is reduced, the buoyancy is recovered, and the water surface emerges from the water under the water. When the ballast water tank is in the second state, gas in the ballast water tank 4 is transmitted to the compressed gas tank 7 by the self-sucking pump 6, external water enters the ballast water tank 4 through the water inlet under the action of pressure, the buoyancy of the external water is offset by increasing the weight, and the external water submerges into the water from the water surface. In other words, the intake and exhaust lines of the self-priming pump 6, the intake/exhaust common line of the ballast tank 4, and the intake/exhaust common line of the compressed gas tank 7 are communicated through a four-way switchable gas valve. State is one, compressed gas tank 7's the inlet air/exhaust common line and the inlet line intercommunication of self priming pump 6, ballast water tank 4's the inlet air/exhaust common line and the exhaust line intercommunication of self priming pump 6, and compressed gas tank 7 internal gas gets into ballast water tank 4 through self priming pump 6. And when the state is two, the four-way valve is switched, the air inlet/exhaust shared pipeline of the compressed air tank 7 is communicated with the exhaust pipeline of the self-sucking pump 6, the air inlet/exhaust shared pipeline of the ballast water tank 4 is communicated with the air inlet pipeline of the self-sucking pump 6, and air in the ballast water tank 4 enters the compressed air tank 7 through the self-sucking pump 6.

The propulsion assemblies, as shown in fig. 1 and 6, are symmetrically arranged on two sides of the sampling box 31, are connected with the depth control assembly, and comprise propeller propellers 8 and battery packs 5, wherein the propeller propellers 8 are mature market products and comprise propeller blades, a flow guide cover, a brushless base, a brushless motor and the like; the propeller thruster 8 is arranged on the lower surface of the depth control assembly (such as the protective cover 9), and can provide thrust in the front and back directions for the collecting device, so that the collecting device can stably move in water bodies with different depths. The battery pack 5 is disposed on the upper surface of the depth control assembly (such as the protection cover 9), and may be disposed inside the protection cover 9, but not limited thereto, and provides a dc power supply for the propeller 8, and the power supply is changed under an external instruction, so that the thrust of the propeller 8 can be changed in real time. The sampling direction is changed by changing the thrust difference of the left propeller thruster 8 and the right propeller thruster 8, and flexible steering and obstacle avoidance can be realized. In the initial stage of plateau lake sampling, a traditional ship towing sampler is adopted for sampling, and a plurality of problems are encountered. For example, whether a scientific investigation ship with a large size or a small propeller-powered rubber boat, a running ship inevitably disturbs a rear water body, so that different water layers are mixed with each other, the collected water sample cannot accurately reflect the real conditions of each water layer, and the sampling is seriously interfered. Even if the ship and sampler spacing is pulled up, this interference cannot be completely avoided and control of the sampler becomes more difficult. Finally, the problem is solved by adopting a mode of providing power by installing a propeller. In the embodiment of this application, the propeller is installed in the left and right sides of sample thief introduction port, has the certain distance from the introduction port, and the screw plane will lean on the back than the introduction port, has avoided the screw to the interference of introduction port water layer like this, and the sampling result reflects the real environment existence of little plastics. The front and back and left and right movement of the collecting device are controlled by the propeller, so that the sampling is more flexible and controllable, and the device is suitable for sampling in a complex environment. In the sampling process of plateau lakes and Beijing reservoirs, the inventor notices that certain risks exist in the safety of sampling personnel in the environment that water is deep, hydraulic change is large, and rescue implementation is difficult. To dangerous sampling environment, throw into the aquatic with sampling equipment on the bank, directly sample at the remote control equipment on the bank, cooperate unmanned aerial vehicle to observe, can avoid the risk of this kind of personnel operation sampling.

In the embodiment of the application, the water body micro-plastic acquisition device further comprises a multi-parameter synchronous monitoring system, wherein the multi-parameter synchronous monitoring system comprises a sensor and/or a positioner, and the sensor comprises at least one of a conductivity sensor, a temperature sensor, a depth sensor, a flow velocity sensor, an ultrasonic obstacle avoidance sensor and the like. Specifically, the sensor may be connected to the sample injection tank 31 through the sensor connection rod 311, but is not limited thereto, and the sensor may include: a depth-temperature-conductivity multi-parameter sensor 313, a mesh opening flow velocity meter 314 and an ultrasonic obstacle avoidance sensor 312, but is not limited to the above.

The depth-temperature-conductivity multi-parameter sensor 313 includes three sensing elements, a conductivity sensor, a temperature sensor and a depth sensor. The conductivity sensor belongs to an electrode type conductivity sensor, and adopts a resistance measurement method to measure the conductivity according to the electrolytic conduction principle. The temperature sensor is composed of a thermistor, changes the change of the current drive water temperature meter through the change of the internal resistance value of the thermistor and is used for measuring the water temperature of the sampling depth. The depth sensor comprises a liquid level sensor for measuring the depth from the water meter and an ultrasonic sensor for measuring the depth from the water bottom; the liquid level sensor consists of piezoelectric ceramics and a current or voltage measuring element, resistance caused by different water body pressures is different, conductivity is different, and the passing current or voltage is different in magnitude, so that the depth from a sampling point to the water meter is measured according to the principle. The depth data of the liquid level sensor is analyzed and then used for regulating and controlling the motion control assembly in real time, so that the sampling is kept at the water layer with the required depth. The ultrasonic sensor comprises an ultrasonic transducer and a measurement and control device, the ultrasonic wave contacts the bottom of the water body and can be reflected, the time intervals from the transmission of ultrasonic signals to the reception of the ultrasonic signals in different water depths are different, and the depth from the sampling point to the bottom is measured according to the principle. The depth data that the ultrasonic sensor acquireed can be used to the alarm of touching the bottom after being analyzed, and the ultrasonic sensor feedback that sets up when the deepest is less than the early warning degree of depth apart from the submarine degree of depth, probably the risk of touching the bottom appears, and real-time regulation and control motion control system removes and turns to deeper waters. The sum of the depth from the water meter measured by the liquid level sensor and the depth from the water bottom measured by the ultrasonic sensor is the total depth of the sampling point. In the actual sampling process, the water depth of different river sections of fresh water environments, particularly small rivers, is greatly changed, if depth data cannot be obtained in real time to guide the sampling process, the phenomenon that sampling equipment is damaged due to bottom contact can occur due to sudden change of a water layer, and some urban rivers can be provided with some underwater pipelines, water treatment or water quality monitoring equipment and the like in the river channels, which cause interference on the sampling process. In the embodiment of the application, the real-time data of the depth and the ultrasonic obstacle avoidance alarm can help a sampling person to judge an underwater complex environment, flexibly turn to or temporarily stop sampling and floating, and avoid the risks.

The net mouth velocity meter 314 can adopt a propeller type velocity sensor, and the propeller rotating speeds caused by different water body velocity are different, so that the velocity is measured according to the principle and is used for measuring the velocity at a specified position in the water body.

The ultrasonic obstacle avoidance sensor 312 converts the ultrasonic signal into an electrical signal, the ultrasonic wave can generate significant reflection when contacting the obstacle to form a reflection echo, and the ultrasonic wave can generate a doppler effect when contacting the moving object to detect the obstacle in the advancing direction. The environment is more complicated under water, and some barriers exist in partial water, and the acquisition device and the acquisition system that this application provided can keep away barrier inductor 312 feedback data through just to the ultrasonic wave of direction of advance at top layer and deep operation, can judge in real time whether there is the barrier in the 5 meters within ranges, and remote control system 1 regulation and control motion system is around, is controlled the removal, avoids the barrier in a flexible way, guarantees the steady operation of system sampling.

In the preferred embodiment of this application, the little plastic sample collection device of water includes two to three sets of horizontal parallel arrangement the collection unit to realize two to three groups of parallel collection and monitoring, can directly obtain two to three groups of parallel data in single sampling process. In consideration of the distribution of micro-plastics in the water body and the difference of water quality parameters, the sampling needs to be provided with enough parallelism to improve the accuracy of the result. At the initial stage of designing a system, the inventor finds that if a parallel acquisition and monitoring system is not additionally arranged, at least one sampling process needs to be repeated in order to obtain parallel data, the field environment is changeable instantly, the completely same path, speed and the like of the two sampling processes are difficult to ensure, the experimental error is increased, and the time and the labor are consumed. In addition, although the accuracy of data can be improved by arranging a plurality of groups of parallels, the operation is simple and the structure is reasonable by considering the space of equipment, the complexity of the structure, the operation difficulty and the required power condition; specifically, for example, a vertical partition plate may be disposed in the middle of the sample injection box 31 to divide the sample injection box into two parallel and symmetrical sample injection channels, and a set of filtering devices 32 is connected to the rear of each sample injection channel through a net head fixing member 33, as shown in fig. 1-2 and 6.

The application also provides a three-dimensional collection system for the micro-plastics in the water body, which comprises a plurality of groups of the micro-plastic sample collection devices in the water body, such as two groups, three groups, four groups and five groups (see fig. 6-7 and 9), which are connected in sequence along the depth direction of the water body.

In the embodiment of the application, in the above three-dimensional collection system for water body micro-plastic, the sample injection boxes 31 of the adjacent groups of water body micro-plastic sample collection devices are connected by at least four connecting rods 111, specifically, four corners of the upper and lower bottom surfaces of the sample injection boxes 31 of the adjacent groups are correspondingly connected by the connecting rods 111, see fig. 7-8.

Four corner edges of the connection surface of the sample injection box 31 of the adjacent groups of water body micro-plastic sample collection devices are provided with protruding connection shafts 115, and two ends of the connection rod 111 are provided with connection rings; the connecting ring is sleeved on the connecting shaft 115 to form a revolute pair.

The front and rear pairs of connecting rods 111 are provided with angle-adjustable supporting hinges at four corners of a parallelogram formed by the bottom edge and the top edge of the sample injection box 31, the supporting hinges comprise acute angle supporting hinges 113 and obtuse angle supporting hinges 114, which are respectively adjacently arranged, see fig. 7; each support hinge comprises two hinge fixing bases 116, two hinge support rods 118 and a gear fastener, the two hinge fixing bases 116 are respectively arranged on the surface of the sample injection box 31 and the connecting rod 111, the first ends of the two hinge support rods 118 are respectively connected with the hinge fixing bases 116 through second pins 117, and the hinge support rods 118 can rotate by taking the second pins 117 as shafts. The second end of one of the hinge support rods 118 is provided with a gear 1191, the second end of the other hinge support rod 118 is provided with a gear groove 1192, the inner groove of the gear groove 1192 is completely matched with the outer edge of the gear 1191, and the two hinge support rods 118 are clamped with the gear groove 1192 through the gear 1191 to form a gear fastener. When the support hinge is used, the rotating placement position of the gear 1191 relative to the gear groove 1192 is changed, and the angle between the two hinge support rods 118 can be changed.

In the embodiment, the acute angle supporting hinge 113 can be adjusted by 0-90 degrees, and the obtuse angle supporting hinge 114 can be adjusted by 90-180 degrees; when the acute angle support hinge 113 is close to 0 degree, the obtuse angle support hinge 114 is close to 180 degrees, the vertical distance between the water body micro-plastic sample collection devices of adjacent groups is minimum, generally, the whole device is in a non-working state at the moment, and all trawl collection assemblies are folded and stored. During the operating condition, acute angle supports hinge 113 and can increase to 90 degrees, and obtuse angle supports hinge 114 and can reduce to 90 degrees, and the perpendicular distance between the little plastic sample collection device of water of adjacent group increases gradually, through adjusting to support the hinge angle and change the perpendicular distance between the collection component of trawl, the perpendicular interval between accurate change sampling water layer. The angle-adjustable hinge connection mode can provide any distance smaller than the length of the connecting rod. The connecting rod 111 can be made of stainless steel alloy with the yield strength as high as 1560Mpa and the tensile strength as high as 1600 Mpa.

In another embodiment of the present application, in the above three-dimensional collection system for micro-plastic in water, the sample injection boxes 31 of adjacent groups of micro-plastic sample collection devices in water are connected by at least four connecting rods 111, see fig. 9; the length of the connecting rod 111 is adjustable, and the vertical distance between the adjacent groups of water body micro-plastic sample collection devices is adjusted by adjusting the length of the connecting rod 111. Specifically, according to sampling requirements, multiple groups of non-telescopic or telescopic metal rods with different lengths can be customized, before sampling begins, the metal rods with proper lengths are vertically fixed between adjacent acquisition devices, and the lengths of the metal rods are the vertical intervals of the trawl acquisition assemblies. The connection mode can be threaded connection, realizes the fixed connection between connecting rod 111 and the appearance case 31 through threaded connection 112, for example, the screw hole is processed respectively as threaded connection 112 in four corner positions at least on the upper and lower surface of appearance case 31, and connecting rod 111 both ends are from taking the external screw thread, can directly screw in the screw hole that appearance case 31 corresponds upper and lower position and form threaded connection, also can use the nut as threaded connection 112.

In the embodiment of this application, among the three-dimensional collection system of the little plastics of water, still include: a remote control system 1 and a trawl control part 2; wherein the content of the first and second substances,

the trawl control part 2 comprises a data acquisition part and an acquisition control part;

the data acquisition part is in communication connection with the sensor and/or the positioner, a PLC (programmable logic controller) is adopted to acquire monitoring data, the measurement information of the sensor is automatically read or collected in real time from the measurement units such as the sensor and the positioner, and the current or voltage analog signal fed back by the sensor is analyzed and processed, converted into a corresponding digital signal value and uploaded to the remote control system 1 on the ship or on the shore through wireless communication;

the collection control component is used for controlling the operation of the collection device, such as controlling the filtration device 32, the opening and closing of the volumetric sampling assembly 10, the starting and closing of the stepping motor 341, the state switching of the depth control assembly, and the opening and closing of the propulsion assembly.

Remote control system 1 can set up on-board or the bank, through wireless communication connection trawl control unit 2, and remote control system 1 saves and handles the data that trawl control unit 2 gathered in real time to assign operating instruction to trawl control unit 2 according to field data, accomplish whole sampling process's control and operating instruction.

Preferably, a GPS locator is arranged in the trawl control part 2, and can transmit positioning information to the remote control system 1 in real time to track and analyze the traveling track of the acquisition device, and the data can be used for adjusting the real-time depth, traveling direction and speed of the acquisition device.

In the embodiment of the application, in the water body micro-plastic three-dimensional acquisition system, the battery pack 5 is connected with the acquisition control part to supply power to the above-mentioned various parts requiring electric power.

The above is a selection of a part of preferable configurations of the present invention, and the above-described respective components may have other configurations. The above-mentioned preferred structures can be used alone, under the prerequisite that does not conflict each other, also can be used in arbitrary combination, and the effect will be better when using in combination.

Preferred embodiment

This embodiment provides a water three-dimensional full-automatic little plastics collection of water and multi-parameter synchronous monitoring system of switching formula multistage filter screen union use for different degree of depth water, and its structure is shown as fig. 1-5, includes: a remote control system 1; a trawl control part 2; a sample introduction box 31; the filtering device 32: a first filter screen 321, a second filter screen 322, a third filter screen 323, a first collecting pipe 324, a second collecting pipe 325, a third collecting pipe 326, a connecting rope 327, a cable 328 and a support rod 329; the net head fixing piece 33, a first pin 331, a hanging ring 332; a small-sized stepping motor 341, a traction rope 346, a first fixed pulley 342, a second fixed pulley 343, a movable pulley 344, and a slide rail 345; a ballast water tank 4, an external battery pack 5, a small self-priming pump 6, a compressed gas tank 7 and a propeller thruster 8; a protective cover 9; a volumetric sampling assembly 10; a connecting rod 111; the system comprises an inductor connecting rod 311, an ultrasonic obstacle avoidance sensor 312, a depth-temperature-conductivity multi-parameter sensor 313 and a net mouth flow velocity meter 314; a sampler handle 12.

Wherein: the remote control system 1 is arranged on a ship deck or a shore; the trawl control part 2 is arranged on the upper surface of the first-layer sampling box 31; the ballast water tank 4, the self-priming pump 6 and the compressed gas tank 7 are sequentially connected and arranged in the protective cover 9 and are fixedly arranged on the side surface of the first-layer sample injection box 31 in a wing-shaped pair; the propeller thruster 8 is fixed on the lower surface of the ballast water tank 4, and the battery pack 5 is fixed on the upper surface of the ballast water tank 4 to provide power for the propeller thruster 8;

the sample injection boxes 31 of adjacent groups with different depths are connected through a connecting rod 111; the sensor is fixed at the inlet of the sample inlet box 31 through a sensor connecting rod 311; a connecting string 327 connecting the first collection pipe 324 and the second collection pipe 325; one end of the supporting rod 329 is connected with the net head fixing piece 33 in a threaded way, and the other end is connected with the third collecting pipe 326 through a cable 328;

one end of the traction rope 346 is connected with the top edge of the net head fixing piece 33 through the hanging ring 332, and the other end of the traction rope is connected with the top edge of the net head fixing piece 33 through the first fixed pulley 342, the movable pulley 344 and the second fixed pulley 343; the stepping motor 341 is fixedly disposed on the inner side of the sample injection box 31.

The water body three-dimensional full-automatic micro-plastic acquisition and multi-parameter synchronous monitoring system combined by the open-close type multi-stage filter screen has the following specific working processes: the different operations are performed by commands issued by the remote control system 1. Firstly, according to the requirement of the collection space of each water layer, a connecting rod 111 with a proper length is selected to be in threaded connection with the sample introduction boxes 31, and the vertical distance between the sample introduction boxes 31 is fixed.

Then, a sampling device with a filter screen in a closed state is placed at the starting point of a sampling area by using a sampler handle 12, and a trawl control part 2 is started; air in the ballast water tank 4 is pumped out through a self-priming pump 6, water is injected into a water inlet of the ballast water tank 4, the device gradually submerges, the sensor transmits the depth of the device from a water meter and the depth from the water bottom to a trawl control part 2 in real time, the trawl control part 2 transmits data to a remote control system 1 in real time for analysis and data display, after the target depth is reached, the trawl control part 2 controls the self-priming pump 6 to release gas in a compressed gas tank 7 to the ballast water tank 4 under the instruction control of the remote control system 1, after the ballast water tank 4 discharges proper amount of water through a water outlet, buoyancy rises, and the acquisition device is finally balanced and fixed at the target depth; subsequently, according to the real-time depth data, the gas injection and drainage of the ballast water tank 4 increase buoyancy or gas discharge and water inlet increase gravity, so that the ballast water tank floats upwards or submerges in real time and is sampled at a specified depth;

then opening the fixed volume sampling assembly 10, namely the 1L cover-type water sampler to collect 1L water samples of each water layer, and closing the water inlet of the water sampler after the water sampling is finished; opening the four groups of external battery packs 5, starting the propeller thruster 8 to work, and starting the acquisition device to move forwards; when the collection device reaches a stable state, the stepping motor 341 receives an instruction to pull down the movable pulley 344, the pull rope 346 (steel wire rope) drives the net head fixing part 33 to be completely opened, the filter screen assembly is in an opening state, and automatic collection of a water sample is started; the water sample sequentially passes through a first filter screen 321, a second filter screen 322 and a third filter screen 323, and the entrapped micro plastic with different particle size intervals is respectively collected in a first collecting pipe 324, a second collecting pipe 325 and a third collecting pipe 326;

meanwhile, the trawl control part 2 reads the parameters measured by the built-in GPS localizer, the ultrasonic obstacle avoidance sensor 312, the depth-temperature-conductivity multi-parameter sensor 313 and the net mouth flow rate meter 314 in real time, and the parameters are converted into digital signals and uploaded to the remote control system 1 in real time through Bluetooth; whether an obstacle exists or whether a bottom-touching risk exists in a 5-meter range is judged according to signals transmitted by the ultrasonic obstacle avoidance sensor 312 and the depth-temperature-conductivity multi-parameter sensor 313, the speed of the left and right propeller propellers 8 is adjusted by the trawl control part 2, and the direction is adjusted to flexibly avoid the obstacle; finally, the step motor 341 releases the movable pulley 344, the steel wire rope drives the net head fixing piece 33 to be completely folded and closed, and the system sampling is finished; after the trawl control part 2 controls the compressed gas tank 7 to release gas and discharge part of water in the ballast water tank 4, the collecting device floats to the surface layer to wait for recovery, and the power supply device, namely the battery pack 5 is closed.

According to the embodiment, the micro plastic sampling device can realize active grading acquisition of micro plastic in water bodies with different depths in a field complex integrated environment and synchronous monitoring of relevant water environment parameters, improves acquisition efficiency, reduces sampling errors, transmits data in real time, is integrated, is easy to carry, install and disassemble, and can finish measurement operation by a single person.

According to the invention, the filter with the openable net port is used, a water sample is not collected before the net port reaches a specified depth, and the net port is directly closed to stop filtering after sampling is finished, so that the node of a filtering process is accurately controlled, the accuracy of the filtering volume is ensured, the loss of collecting the sample in the net in the process of collecting and releasing the equipment is avoided, and the reliability and the accuracy of data are ensured; the good form of the filter screen component is fixed by the fixing rod, the mooring rope and the connecting rope, the filter screen component filters a water sample layer by layer through the multistage filter screens with the pore diameters from large to small, the pore diameter interval of the filter screens can be set to be 0.05-5 mm, the component can slow down the blocking speed of the filter screens and increase the filtering volume, the minimum particle diameter of collected micro-plastics can reach 0.05 mm, and the micro-plastics in the filter material collected in a grading mode can be conveniently extracted, analyzed, observed and identified in a laboratory. In addition, the invention uses the propeller behind the opening of the sample introduction box to provide power, thereby effectively avoiding the influence of the traditional power ship body on sampling, combining the ultrasonic obstacle avoidance sensor, being capable of remotely controlling obstacle avoidance and being more flexibly applied to the collection of micro-plastics in water surface and underwater environment. Aiming at the limitation that the traditional surface trawl net can only collect the surface water sample, the depth distance of synchronous collection of a plurality of groups of filter screen assemblies is controlled by the adjustable angle connecting hinge or the adjustable length telescopic connecting rod, and the depth control system can control the depth of the sampling equipment in real time, so that the three-dimensional sampling can more accurately reflect the occurrence current situation of the micro-plastic in the water body. The sampling system consists of a plurality of groups of trawl net assemblies, the trawl nets can open or close the sampling ports according to signals, the whole sampling system can operate on the surface layer of the water body and can also operate completely underwater, and the underwater operation can avoid the influence of water surface waves on sampling. According to the invention, the flow rate meter and the depth-temperature-conductivity multi-parameter sensor are fixed at the opening of the sample injection box, the monitoring of the water body related parameters is integrated in the micro-plastic acquisition device, more systematic and comprehensive hydrological and water environment parameter data can be synchronously obtained in real time so as to optimize and adjust a micro-plastic distribution sampling scheme in real time, and the analysis of factors influencing the micro-plastic environmental behavior is facilitated. The technology is very suitable for three-dimensional dynamic monitoring of the micro-plastic on the surface layer of the water environment, particularly the low-flow-speed water body, particularly the underwater environment.

Finally, it is further noted that, in the present application, relational terms such as left and right, first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

While the application has been disclosed by the description of specific embodiments thereof, it should be understood that various modifications, adaptations, and equivalents may occur to one skilled in the art and are within the spirit and scope of the appended claims. Such modifications, improvements and equivalents are intended to be included within the scope of the claims.

Claims

1. The utility model provides a little plastics collection system of water, includes the collection unit, its characterized in that, the collection unit includes:

a sample introduction box;

the filter device comprises a filter screen and a collecting pipe connected with the tail part of the filter screen;

the net head fixing piece is used for connecting the outlet of the sample inlet box and the head part of the filter screen;

the net port opening and closing control assembly is arranged on the sampling box, is connected with the net head fixing piece and is used for controlling the net port of the filtering device to be closed;

and the trawl control component is in communication connection with the net port opening and closing control component and controls the operation of the net port opening and closing control component after receiving the instruction.

2. The water body micro-plastic collecting device according to claim 1, wherein the filtering device is a multi-stage filter, the filter screen head of each stage of filter is connected with the sample feeding box through the screen head fixing part, and the filter screen filtering pore size of each stage of filter decreases from inside to outside in sequence according to the increase of stages; the collecting pipes of each stage of filter are connected in sequence through connecting ropes.

3. The water body micro-plastic collection device of claim 2, wherein the filter device further comprises a support bar and a cable; one end of the supporting rod is connected with the net head fixing piece and/or the sample injection box, and the other end of the supporting rod is connected with the cable; one end of the cable is connected with the support rod, and the other end of the cable is connected with the collecting pipe of the last stage of filter.

4. The water body micro-plastic collecting device as claimed in claim 1, wherein the net head fixing piece is a hard rectangular frame, and the size of the net head fixing piece is matched with the outlet of the sampling box; the bottom edge of the net head fixing piece is fixedly connected with the bottom edge of the sample injection box outlet, and two side edges of the net head fixing piece are respectively formed by connecting two sections of connecting rods with basically equal lengths;

the first ends of the two connecting rods are connected through a first pin, the second ends of the two connecting rods are connected through a spring, and the second ends of the two connecting rods are respectively connected with the top edge and the bottom edge of the net head fixing piece;

or the first ends of the two connecting rods are connected through a torsion spring, and the second ends of the two connecting rods are respectively connected with the top edge and the bottom edge of the net head fixing piece.

5. The water body micro-plastic collecting device as claimed in claim 1, wherein the net head fixing piece comprises a hard bottom edge, a hard top edge and a flexible side edge, and the shape and the size of the net head fixing piece are matched with the outlet of the sampling box when the net head fixing piece is opened; the bottom edge of the net head fixing piece is fixedly connected with the bottom edge of the outlet of the sample injection box, and the top edge of the net head fixing piece is connected with the net port opening and closing control component; two ends of the flexible side edge are connected through an elastic piece.

6. The water body micro-plastic collecting device as claimed in claim 4 or 5, wherein the net mouth opening and closing control assembly comprises a stepping motor, a traction rope, a movable pulley, a first fixed pulley, a second fixed pulley and a slide rail; wherein the content of the first and second substances,

the first fixed pulley and the second fixed pulley are respectively arranged on two sides of the top of the same side wall of the sample injection box, a sliding rail is arranged between the first fixed pulley and the second fixed pulley, and the sliding rail is provided with the movable pulley; one end of the traction rope is connected with the top of the net head fixing piece, and the other end of the traction rope is connected with the second fixing pulley through the first fixing pulley and the movable pulley in sequence; the stepping motor is connected with the movable pulley.

7. The water body micro-plastic collecting device as claimed in claim 4 or 5, wherein the net mouth opening and closing control assembly comprises a stepping motor, a traction rope, a sliding block, a first fixed pulley and a sliding rail; wherein the content of the first and second substances,

the first fixed pulley is arranged at the top of the sample feeding box, the slide rail is vertically arranged on the side wall of the outlet of the sample feeding box, and the slide block is arranged on the slide rail; one end of the traction rope is connected with the top edge of the net head fixing piece through the sliding block, and the other end of the traction rope is connected with the stepping motor through the first fixing pulley in sequence.

8. The water body micro-plastic collecting device according to any one of claims 1-3,

the net head fixing piece comprises a hard bottom edge, a hard top edge and a flexible side edge, and the shape and the size of the net head fixing piece are matched with the outlet of the sampling box when the net head fixing piece is opened; the bottom edge of the net head fixing piece is fixedly connected with the bottom edge of the outlet of the sample injection box, and the top edge of the net head fixing piece is connected with the net port opening and closing control component;

the net port opening and closing control assembly comprises a stepping motor, a crank mechanism, a sliding block and a sliding rail; the sliding rail is vertically arranged on the side wall of the outlet of the sampling box, the sliding block is arranged on the sliding rail, and the sliding block is provided with a connecting piece used for being connected with the top edge of the net head fixing piece; one end of the crank mechanism is connected with the sliding block, and the other end of the crank mechanism is connected with the stepping motor.

9. The water body micro-plastic collecting device as claimed in any one of claims 1-3,

the net head fixing piece comprises a hard bottom edge, a hard top edge and a flexible side edge, the shape and the size of the net head fixing piece are matched with the outlet of the sample injection box when the net head fixing piece is opened, the bottom edge of the net head fixing piece is fixedly connected with the bottom edge of the outlet of the sample injection box, and the top edge of the net head fixing piece is connected with the net port opening and closing control assembly;

the net port opening and closing control assembly comprises a stepping motor, a transmission gear and a driven crawler; the driven crawler belt comprises a towing part and a rack belt sleeved on the periphery of the towing part; the towing part is fixed on the side wall of the sampling box, and the height of the towing part is equivalent to that of the sampling box; one end of the rack belt is provided with a connecting piece used for being connected with the top edge of the net head fixing piece, the rack belt is meshed with the transmission gear, and the transmission gear is connected with the stepping motor.

10. The water body micro-plastic collecting device as claimed in any one of claims 1-3, further comprising: a motion control assembly comprising a depth modulation assembly and/or a propulsion assembly; the depth regulating and controlling assembly controls the collecting device to float upwards and submerge downwards in the vertical direction; the pushing assembly controls the collecting device to move back and forth and left and right on the horizontal plane.

11. The water body micro-plastic collecting device as claimed in claim 10, wherein the depth control assembly is symmetrically arranged on a pair of side walls of the sampling box perpendicular to the water surface in a wing shape; the degree of depth regulation and control subassembly includes ballast water tank, self priming pump, compressed gas jar and group battery, ballast water tank, self priming pump, compressed gas jar are according to keeping away from gradually the direction of advance appearance case sets gradually and connects, and fixed mounting is in the protection casing, the self priming pump sets up the ballast water tank with in the middle of the compressed gas jar with control the ballast water tank admit air/give vent to anger, drainage/intake and the intake/give vent to anger of compressed gas jar.

12. The water body micro-plastic collecting device as claimed in claim 11, wherein in the depth regulating assembly, the upper part of the ballast water tank is provided with a vent, the self-priming pump is provided with an air inlet and an air outlet, and the compressed air tank is provided with a vent; and the air inlet pipeline and the air outlet pipeline of the self-priming pump, the air inlet/air outlet shared pipeline of the ballast water tank and the air inlet/air outlet shared pipeline of the compressed air tank are communicated through a four-way switchable air valve.

13. The water body micro-plastic collection device of claim 11, wherein the propulsion assembly comprises a propeller and a battery pack; the propeller thruster is arranged below the ballast water tank and behind the inlet of the sample injection tank.

14. The water body micro-plastic collecting device according to any one of claims 1-5 and 11-13, further comprising a multi-parameter synchronous monitoring system, including a sensor and/or a locator, wherein the sensor includes at least one of a conductivity sensor, a temperature sensor, a depth sensor, a flow rate sensor, an ultrasonic obstacle avoidance sensor, and the like.

15. The device for collecting the micro-plastics in the water body according to any one of claims 1 to 5 and 11 to 13, which comprises two to three sets of collecting units which are transversely arranged in parallel.

16. The three-dimensional collection system for the micro-plastics in the water body is characterized by comprising a plurality of groups of the micro-plastic sample collection devices in the water body, which are connected in sequence, according to any one of claims 1 to 15.

17. The three-dimensional collection system for the micro-plastic in the water body according to claim 16, wherein the sample injection boxes of the micro-plastic sample collection devices in adjacent groups are connected through a connecting rod, four corner edges of a connecting surface of the adjacent sample injection boxes are provided with protruding connecting shafts, and two ends of the connecting rod are provided with connecting rings; the connecting ring is sleeved on the connecting shaft to form a revolute pair;

the front and rear pairs of connecting rods and the bottom edge and the top edge of the sampling box form a parallelogram, supporting hinges with adjustable angles are arranged at the four corners of the parallelogram, and the supporting hinges comprise acute angle supporting hinges and obtuse angle supporting hinges which are respectively arranged adjacently;

every support hinge includes two hinge unable adjustment base, two hinge bracing pieces and a gear fastener, two hinge unable adjustment base set up respectively in the surface of advance appearance case with on the connecting rod, two the first end of hinge bracing piece respectively through the second pin with hinge unable adjustment base connects, and the second end of one of them hinge bracing piece is equipped with the gear, and the second end of another hinge bracing piece is equipped with the gear recess, the inside recess of gear recess with the outer fringe of gear matches completely, two the hinge bracing piece passes through the gear with gear recess joint constitutes the gear fastener is used for controlling two the contained angle that the hinge bracing piece becomes.

18. The three-dimensional collection system for the micro-plastic in the water body according to claim 16, wherein the sample injection boxes of the micro-plastic sample collection devices in adjacent groups are connected through at least four connecting rods, and the ends of the connecting rods are fixedly connected with the sample injection boxes through threads; the connecting rod is a telescopic connecting rod or a non-telescopic connecting rod.

19. The three-dimensional collection system for micro-plastics in a water body according to any one of claims 16-18, further comprising: a trawl control component and a remote control system; wherein the content of the first and second substances,

the trawl control part comprises a data acquisition part and an acquisition control part; the data acquisition component is in communication connection with the sensor and/or the positioner, adopts a PLC (programmable logic controller) to acquire monitoring data and uploads the monitoring data to the remote control system; the acquisition control part is used for controlling the operation of the stepping motor, the fixed-volume sampling assembly, the depth regulating assembly and/or the propelling assembly;

the remote control system is in communication connection with the trawl control component, receives, stores and processes data transmitted by the trawl control component, and issues an operation instruction to the trawl control component according to field data.