CN114184651A

CN114184651A - Ammonia nitrogen detection equipment and water quality detection method

Info

Publication number: CN114184651A
Application number: CN202010962288.6A
Authority: CN
Inventors: 不公告发明人
Original assignee: Quantaeye Beijing Technology Co ltd
Current assignee: Quantaeye Beijing Technology Co ltd
Priority date: 2020-09-14
Filing date: 2020-09-14
Publication date: 2022-03-15

Abstract

The invention relates to ammonia nitrogen detection equipment and a water quality detection method, wherein the detection equipment comprises an ammonia gas detection unit and an ammonia gas generation unit; the ammonia gas generation unit comprises an electrolysis electrode, and the electrolysis electrode electrolyzes the water body to be detected entering the ammonia gas generation unit under the condition of electrifying current to generate OH^‑At said OH^‑Under the action of (3), NH in the water body to be detected₄ ⁺And the ammonia gas is converted into ammonia gas and enters the ammonia gas detection unit.

Description

Ammonia nitrogen detection equipment and water quality detection method

Technical Field

The invention belongs to the field of environmental protection, and particularly relates to the field of water quality monitoring of water bodies, in particular to water bodies such as river water, lake water and the like.

Background

With the increasing enhancement of environmental protection concept, new requirements and challenges are increasingly presented for the water quality monitoring of various natural water bodies, domestic or industrial wastewater and secondary purified water.

Whether natural water bodies, such as river water, lake water and the like, or secondary purified water obtained after wastewater treatment, the control and detection of the nitrogen element content in the water bodies are one of the important points of research or treatment of various environmental protection processes. In actual detection or monitoring methods, the existing methods are usually based on sampling in the field, and then determining the content of various target elements or substances in the water body by a laboratory. Therefore, a large amount of manpower and material resources are required. In addition, although the detection result usually has guaranteed precision and strong reliability, the detection or monitoring effectiveness is poor overall, which also reduces the detection significance to a certain extent. For example, it usually takes several days or more to obtain a test result from one sampling. In addition, since the field sampling scale is limited, it is difficult to perform large-scale and large-area water quality monitoring in a short time.

Furthermore, various detection methods based on unmanned detection or based on the internet of things have appeared. For example:

reference 1 provides an automatic riverway water quality monitoring system and method, the system includes a riverway monitoring platform and an automatic riverway monitoring device deployed in a monitoring area, wherein the automatic riverway monitoring device includes a solar monitoring station and an unmanned monitoring ship, the riverway monitoring platform is used for comprehensive management, monitoring task management and monitoring data management of the automatic riverway monitoring device, the solar monitoring station is used for water quality monitoring at a fixed point location and berthing and charging of the unmanned monitoring ship, and the unmanned monitoring ship is used for automatically monitoring riverway water quality, a riverway three-dimensional structure and ground conditions in the monitoring area.

Reference 2 provides a water quality monitoring system and a water quality monitoring method based on the internet of things, the system includes a plurality of water quality monitors and a base station, and the water quality monitors report energy packets to the base station; the base station extracts water quality monitoring instrument serial number, residual energy, energy utilization rate and timestamp in the energy packet, adopts water quality monitoring instrument residual service time generation model water quality monitoring instrument serial number, residual energy, energy utilization rate and timestamp to generate the current residual service time of the water quality monitoring instrument, if the current residual service time is less than a preset threshold value, the water quality monitoring instrument is identified as the water-free water quality monitoring instrument, sends a position coordinate acquisition request to the water-free water quality monitoring instrument, receives a returned position coordinate, sends a notification message to a preset terminal, and the notification message comprises a position coordinate and a water quality monitoring instrument serial number so as to enable the preset terminal to receive and display the notification message.

In the detection or monitoring devices or methods including the above, the detection of the content of nitrogen elements in the water body is generally performed by using an ammonia nitrogen probe.

The working principle of the existing online ammonia nitrogen probe is mainly based on the following two typical detection methods:

the first method is mainly based on spectrophotometry, for example, measurement is carried out based on the national standard (HJ 536-2009) ammonia nitrogen detection method. Which mixes a sample to be analyzed with a reaction reagent and then adds NH in the solution₄ ⁺Ion conversion to ammonia (NH)₃) Ammonia gas is released from the sample being analyzed. The ammonia gas is then transferred to a measuring cell containing the indicator and redissolved in the indicator. The reaction causes the color of the solution to change, and the ammonia nitrogen detector measures by using a colorimetric method and then calculates and obtains the concentration value of the ammonia nitrogen.

The second method is ammonia gas sensitive electrode method, which is to add certain reagent and NH₄ ⁺Ion conversion to ammonia (NH)₃) Free NH₃Enters the ion electrode through a semi-permeable membrane to participate in chemical reaction, changes the pH value of electrolyte in the electrode, the change amount of the pH value and NH₃The concentration of (a) is in a linear relationship, and the concentration is sensed by an electrode and converted into the ammonia nitrogen concentration.

The two methods are both a test mode similar to a shore station, and a considerable amount of reagent or indicator needs to be added during detection so as to meet the requirements of a test optical path, color development and the like. Taking a relatively common Hash Amtax Compact II type ammonia nitrogen detector on the market as an example, the reagent consumed each month is about 1L. Meanwhile, the reagent and the water sample need to be fed in and out through mechanical devices such as a pump and a valve, the size is relatively large, and the test flow is relatively complex.

Therefore, although various automatic monitoring or on-line detection methods based on ammonia nitrogen probes have been tried to some extent, such on-line detection equipment generally needs to add a considerable amount of strong alkali reagent to adjust the pH environment, the reagent consumption is relatively large, and the addition manner is complicated. Therefore, improvement in efficiency of on-line detection capability and convenience is still insufficient.

Reference documents:

reference 1: CN110456013A

Reference 2: CN108490045A

Disclosure of Invention

Problems to be solved by the invention

Based on the defects of the existing method for online or automatic detection of the content of nitrogen elements in water, the invention provides an improved device and method for online or automatic detection of nitrogen elements in water based on an ammonia nitrogen probe.

According to the detection equipment, the ammonia gas generation unit comprising the electrolysis electrode is introduced into the ammonia nitrogen probe, so that the water quality monitoring of the water body can be stably realized for a long time under the condition of not adding an alkaline reagent. In addition, as an alkaline reagent is not required to be added, the overall size of the ammonia nitrogen probe device can be obviously reduced, and large-scale arrangement in a water body is facilitated, so that compared with the conventional detection or monitoring device, the ammonia nitrogen probe device has the advantages that the data collection scale is obviously increased, and the adaptability, effectiveness and reliability of the detection or monitoring method are obviously improved.

Means for solving the problems

After long-term intensive research, the inventors found that the technical problems can be solved by implementing the following method:

[1] the invention firstly provides ammonia nitrogen detection equipment, which comprises:

an ammonia gas detection unit;

an ammonia gas generation unit;

the ammonia gas generation unit comprises an electrolysis electrode, and the electrolysis electrode electrolyzes the water body to be detected entering the ammonia gas generation unit under the condition of electrifying current to generate OH^-，

At the OH group^-Under the action of (3), NH in the water body to be detected₄ ⁺And the ammonia gas is converted into ammonia gas and enters the ammonia gas detection unit.

[2] The apparatus according to [1], wherein a semipermeable membrane is provided between the ammonia gas generating unit and the ammonia gas detecting unit, and the semipermeable membrane is impermeable to liquid molecules.

[3] The apparatus according to [1] or [2], wherein the ammonia gas generation unit comprises one or more of the electrolysis electrodes.

[4] The apparatus according to any one of [1] to [3], wherein the water body to be measured in the ammonia gas generation unit is selected from one of river water, lake water, seawater, domestic or industrial wastewater, or purified domestic or industrial wastewater.

[5] The apparatus according to any one of [1] to [4], wherein the ammonia gas generation unit includes a pre-electrolysis unit, and at least one of the electrolysis electrodes is disposed in the ammonia gas generation unit at least in the pre-electrolysis unit.

[6]According to [1]]～[5]Any one of the devices, the ammonia gas generation unit further comprises a counter electrode, and the counter electrode electrolyzes the water body to be detected entering the ammonia gas generation unit under the condition of electrifying current to generate H⁺。

[7] The device according to any one of the items [1] to [6], wherein the ammonia gas detection unit comprises an ammonia nitrogen detection component, the ammonia nitrogen detection component comprises a reaction cavity and a liquid storage cavity, and the volume of the liquid storage cavity is larger than that of the reaction cavity.

[8] The apparatus of [7], wherein the reaction chamber comprises a conductivity-responsive electrode.

[9]According to [1]]～[7]Any one of the devices, the ammonia gas detection unit calculates NH in the water body to be detected based on the change of optical or chemical parameters₄ ⁺And (4) concentration.

[10] The equipment according to any one of the items [1] to [9], wherein the ammonia nitrogen detection equipment further comprises a temperature compensation unit.

[11] The apparatus according to any one of [1] to [10], wherein the current is direct current.

[12] Further, the invention provides a device for detecting the water quality of a water body, which comprises one or more devices according to any one of the items [1] to [11].

[13]In addition, the present invention also provides a method for on-line detection of water quality of a river water body, the method comprising using the method according to [1]～[12]Any one of the devices described detects NH in river water₄ ⁺The concentration of (c).

[14] The method according to [13], wherein 2 or more of the apparatuses according to any one of [1] to [12] are used per square kilometer of the water surface area of the water body.

ADVANTAGEOUS EFFECTS OF INVENTION

Through the use of the technical scheme, the invention can obtain the following technical effects:

(1) according to the invention, the electrolysis electrode is added into the ammonia nitrogen detection equipment, so that the water body to be detected can be electrolyzed to increase the pH value of the water body to be detected, and ammonium ions in the water body to be detected are converted into ammonia gas, and compared with the traditional equipment, no (strong) alkaline reagent is required to be added additionally.

(2) As an alkaline reagent is not required to be additionally added, convenience in the aspects of detection method and equipment maintenance is brought, and the water quality detection efficiency is greatly improved.

(3) Because need not additionally to add alkaline reagent, consequently, also need not to hold the container and the controlling means of alkaline reagent among the traditional equipment, saved ammonia nitrogen check out test set's volume, be convenient for large-scale preparation and arrange the use to not only can show and improve data collection efficiency, also can not additionally increase the maintenance cost.

(4) Because an alkaline reagent is not required to be additionally added, the detection period can be greatly improved; in addition, due to the convenience in maintenance, the detection equipment can be used for detecting the water quality in the water body in a large scale in a complex place or under difficult geographical conditions, which is difficult to apply by the conventional detection equipment, so that the environmental applicability of the detection equipment is greatly improved.

In a word, the detection equipment provided by the technical scheme of the invention can be used for conveniently carrying out high-efficiency large-scale detection on the water body to be detected under various conditions, and has excellent detection accuracy and stability.

Drawings

FIG. 1: schematic diagram of ammonia nitrogen detection equipment in one embodiment of the invention

FIG. 2: schematic diagram of ammonia nitrogen detection equipment in one embodiment of the invention

FIG. 3: detection result characterization in one embodiment of the invention

Fig. 4 a-4 c: example structure of ammonia nitrogen detection part in ammonia gas detection unit

Fig. 5 a-5 b: example structure of ammonia nitrogen detection part in ammonia gas detection unit

1,1': ammonia gas sensitive material

2,2': electrolytic electrode (cathode)

3,3': electrolytic counter electrode (anode)

4,4': semipermeable membranes

5: air guide valve

6: reaction chamber

7: liquid storage cavity

8: electrode for detecting conductivity

9: cut-off member

10: communication path

11: electrical connection channel

12: functional cavity

111: electric wire

Detailed Description

The present invention will be described in detail below. The technical features described below are explained based on typical embodiments and specific examples of the present invention, but the present invention is not limited to these embodiments and specific examples. It should be noted that:

in the present specification, the numerical range represented by "numerical value a to numerical value B" means a range including the end point numerical value A, B.

In the present specification, the numerical ranges indicated by "above" or "below" mean the numerical ranges including the numbers.

In the present specification, the meaning of "may" includes both the meaning of performing a certain process and the meaning of not performing a certain process.

As used herein, the term "optional" or "optional" is used to indicate that certain substances, components, performance steps, application conditions, and the like are used or not used.

In this specification, unless otherwise specified, "normal temperature" generally refers to the normal temperature of the water to be measured, i.e., the temperature is between 5 ℃ and 25 ℃.

In the present specification, the unit names used are all international standard unit names, and the "%" used means weight or mass% content, if not specifically stated.

In the present specification, reference to "some particular/preferred embodiments," "other particular/preferred embodiments," "embodiments," and the like, means that a particular element (e.g., feature, structure, property, and/or characteristic) described in connection with the embodiment is included in at least one embodiment described herein, and may or may not be present in other embodiments. In addition, it is to be understood that the described elements may be combined in any suitable manner in the various embodiments.

< first aspect >

The invention provides ammonia nitrogen detection equipment in a first aspect, which at least comprises an ammonia gas detection unit and an ammonia gas generation unit.

Ammonia gas detection unit

In the invention, the ammonia gas detection unit detects the amount of ammonia gas by generating a physical or chemical reaction after the ammonia gas sensitive material is contacted with the ammonia gas. In the invention, the ammonia gas detection unit comprises an ammonia nitrogen detection component, and the basic structure of the ammonia nitrogen detection component comprises an ammonia gas sensitive material and a gas guide valve under the condition shown by a dotted line in figure 1. Further, it is preferable for the semipermeable membrane to be included in the ammonia gas detecting unit as a part of the ammonia gas detecting unit, but it should be appreciated that such a case is not essential, that is, the semipermeable membrane may not be included in the ammonia gas detecting unit described above in any other desired case.

In some embodiments of the invention, the ammonia sensitive material may be selected from those that produce an optical change upon contact with ammonia, such as a color change material. The material can generate different color changes or generate reflected light with different properties along with different amounts of ammonia gas after being contacted with the ammonia gas, the color or the reflected light is detected by an additional optical detection device, and the amount of the ammonia gas absorbed by the ammonia gas sensitive material is determined by comparing with a standard sample.

The kind or morphology of such ammonia gas sensitive material is not particularly limited, and can be selected from those in the art as needed. The ammonia gas sensitive material finally converts color change or optical signals into data information based on a colorimetric method or an optical chromatographic analysis method so as to present a detection result. It is advantageous for these materials that the adsorption with ammonia gas is unstable (recoverable) over time under certain conditions so that the adsorbed ammonia gas is desorbed from the surface of the ammonia gas sensitive material by the action of the outside.

In other embodiments of the invention, for ammonia sensitive materials, those materials may be selected that have a chemical change, such as a change in pH, upon contact with ammonia. In some preferred embodiments of the invention, the pH of these materials changes in a linear fashion with increasing amounts of ammonia. In such specific embodiments, these ammonia-sensitive materials include acidic materials that include acidic species having a pH of less than 7, preferably less than 6, and more preferably less than 5. The form of the acidic material is not particularly limited, and may be a liquid or semi-solid state at normal temperature. In some preferred embodiments, the acidic material may include one or more protic acids, and more particularly may include a mixture of one or more of boric acid, sulfuric acid, hydrochloric acid.

During detection, the amount of the ammonia gas absorbed by the ammonia gas sensitive material is obtained by detecting the pH value or the change of the pH value of the ammonia gas sensitive material absorbing the ammonia gas. Also, in a further preferred embodiment of the present invention, the ammonia gas sensitive material has instability (recoverability) in combination with ammonia gas over time, that is, the absorbed ammonia gas can be removed under the action of external conditions (such as light, heat and the like), so that the material can be self-renewed for the next detection.

In other embodiments of the invention, the ammonia gas sensitive material may be a material or reagent that changes in electrical properties upon absorption of ammonia gas, and such material or reagent may, for example, have an initial conductivity, and the change in conductivity after absorption of ammonia gas exhibits a characteristic that changes linearly with the amount of ammonia gas absorbed.

In addition, as the ammonia gas sensitive material, there may be mentioned those having selective adsorption with ammonia gas and having a change in electrical signal after adsorption. Typically, it may be selected from a composite of a polymer and a metal oxide, etc., and as such, it is advantageous that such a material has a short recovery time.

In addition, although the ammonia gas sensitive material theoretically includes any material which can be analyzed by liquid chromatography or gas chromatography after absorbing ammonia gas. However, in terms of practical use, although detection accuracy can be ensured, their apparatus is complicated in design and high in cost, and therefore, it is preferable that these ammonia gas absorbing materials based on liquid or gas chromatography are not used unless absolutely necessary.

For the ammonia gas detecting unit of the present invention, in some specific embodiments, it is separated from the ammonia gas generating unit described below by a semi-permeable membrane.

There is in principle no particular restriction on the semi-permeable membrane, which allows the passage of gas and terminates the passage of liquid molecules. In some preferred embodiments of the present invention, such a semipermeable membrane may be made of natural polymer material membrane, synthetic polymer material membrane, ceramic material or foam material. Without limitation, these semipermeable membranes may be a single layer or a multi-layer composite membrane layer, as long as the materials are chemically and physically inert to ammonia gas, according to actual needs.

In addition to the ammonia gas sensitive material and the semi-permeable membrane described above, in some specific embodiments of the present invention, the ammonia gas detecting unit further comprises a gas inlet and a gas outlet channel. Typically, a gas inlet channel may be provided between the semi-permeable membrane and the ammonia gas sensitive material. In some embodiments, such gas inlet and gas outlet passages may be closed by an auxiliary control member to effect switch closure. For example, when the detection is started, the gas inlet channel is in an open state and the gas outlet channel is in a closed state, and after the detection is finished or the detection equipment is in a dormant state, the gas inlet channel is in a closed state, and the gas outlet channel can be in an open or closed state according to the requirement. In addition, the gas discharge channel is arranged in a mode of being beneficial to releasing the ammonia adsorbed by the ammonia sensitive material, so that desorption and release of the ammonia and recovery or regeneration and utilization of the ammonia sensitive material after detection are facilitated.

The ammonia nitrogen detecting part in the ammonia gas detecting unit used in some embodiments of the present invention is exemplarily described below.

Fig. 4a to 5b show a structure of a component for detecting ammonia nitrogen, which can be used for detecting the content of ammonia nitrogen in a water body to be detected.

The ammonia nitrogen detection component comprises a reaction cavity 6 and a liquid storage cavity 7, wherein liquid ammonia sensitive materials can be contained in the reaction cavity 6 and the liquid storage cavity 7, and the ammonia nitrogen content in a water body to be detected is detected by detecting the change (rate) of the conductivity or the pH value and the like of the ammonia sensitive materials during detection.

The reaction chamber 6 is used for accommodating a reaction reagent (such as boric acid solution as described above as an ammonia gas sensitive material) and receiving ammonia gas in a sample to be tested. The volume of the liquid storage chamber 7 is larger than that of the reaction chamber 6, and is used for storing reaction reagents. In some specific embodiments, the volume of the reservoir chamber 7 is more than 50 times, preferably more than 200 times, more preferably more than 1000 times, and more preferably more than 2500 times the volume of the reaction chamber 6. For example, the reaction chamber 6 has a volume of 0.1ml to 2ml, preferably 0.1ml to 0.5ml, more preferably 0.1ml to 0.2ml, and the reservoir chamber 7 has a volume of 50ml to 500 ml.

The ammonia nitrogen detection component also comprises a conductivity response type electrode 8 (also referred to as a conductivity detection electrode 8 in the text). In some specific embodiments, the detection end of the electrode 8 is located in the reaction chamber 6 for detecting parameters of the reaction reagent, such as pH, conductivity, etc.

In addition, the ammonia nitrogen detecting means in the preferred embodiment of the present invention detects the ammonia nitrogen concentration by the change (rate) of the conductivity through the use of the conductivity-responsive electrode, from the following points of view:

first, the conductivity is more sensitive to detection;

secondly, the measurement result is more accurate (relatively, only two decimal points can be read when the pH value is detected);

third, the probe for detecting conductivity has a longer life.

The reservoir chamber 7 and the reaction chamber 6 can be communicated or isolated in a controlled and automatic manner.

When the reaction reagent in the reaction chamber 6 reacts to a predetermined degree, for example, when the liquid ammonia sensitive material in the reaction chamber 6 reacts with ammonia to saturation, the parameters detected by the ammonia nitrogen detection component can no longer accurately reflect the ammonia nitrogen concentration in the sample to be detected. Under a possible working mode, the ammonia nitrogen detection component detects the ammonia nitrogen concentration of surface water, works once every 10 minutes, and after 1-2 days of work, a reaction reagent in the reaction cavity 6 is saturated by ammonia gas, and a signal reaches the maximum value.

At this time, the reservoir chamber 7 and the reaction chamber 6 are communicated, the reservoir chamber 7 automatically replenishes the reaction chamber 6 with the stored reaction reagent, and the fresh ammonia gas sensitive material (for example, boric acid solution or the like) in the reservoir chamber 7 is exchanged to the reaction chamber 6 by, for example, solution diffusion or the like. When the reaction reagent in the reaction cavity 6 is replenished, the reaction cavity 6 and the liquid storage cavity 7 are isolated again, and the ammonia nitrogen detection part continues to work in a new period.

The above-mentioned predetermined degree may be determined, for example, by judging time, conductivity, or the like. Specifically, for example, during the detection process, ammonia gas continuously enters the reaction chamber 6, so that the absolute value of the electrical conductivity inside the reaction chamber gradually increases, and finally, when the maximum range or the predetermined value of the electrical conductivity is reached, it is determined that the reaction reagent reacts to the predetermined degree. Also for example, a time is calculated based on the frequency of the test and the average amount of the reagent required for the test, and the time is set as a time for replenishing the reaction chamber 6 with the stored reagent.

It should be understood that, when the reagent in the reservoir chamber 7 diffuses into the reaction chamber 6, the concentration of the reagent in the reservoir chamber 7 gradually decreases, and the concentration of the reagent in the reaction chamber 6 gradually increases, so long as the reaction chamber 6 is replenished with fresh reagent, and the reaction between the reagent and ammonia can be realized no matter what the concentration of the ammonia sensitive material (boric acid solution) in the reaction chamber 6 is.

From this, ammonia nitrogen detection part is from taking "reagent reaction" storehouse, when the reagent consumption in reaction chamber 6 and lead to ammonia nitrogen detection part no longer to have the detection ability or detectivity to descend, thereby the reagent in two chambeies has concentration difference and the reagent of stock solution chamber 7 diffuses to reaction chamber 6 naturally, thereby stock solution chamber 7 supplements reagent to reaction chamber 6 automatically, this has in time resumeed ammonia nitrogen detection part's detection ability or has improved detectivity, and then lengthened ammonia nitrogen detection part single adding reagent's life.

Taking the ammonia nitrogen detection part with the reaction cavity 6 and the liquid storage cavity 7 with the sizes as an example, after the liquid storage cavity 7 is added with the reagent every time, the service life of the ammonia nitrogen detection part can be as long as 1 to 2 years.

As shown in fig. 4a and 4b, in one embodiment of the ammonia nitrogen detecting component in the ammonia gas detecting unit provided by the present disclosure, the liquid storage chamber 7 may be located above the reaction chamber 6, and a communication passage 10 that can be blocked by a solenoid valve described later may be provided between the liquid storage chamber 7 and the reaction chamber 6.

The "radial direction" of the reaction chamber 6 is a direction perpendicular to the vertical direction a of the reaction chamber 6, which will be described later.

The lower end of the reaction chamber 6 is used for receiving ammonia gas (including, for example, NH) in a sample to be measured₃·H₂O), in particular, the lower end of the reaction chamber 6 may be provided with a semipermeable membrane 4, and ammonia gas can penetrate through the semipermeable membrane 4 and enter the reaction chamber 6. The distance between the detection end of the conductivity detection electrode 8 and the semipermeable membrane 4 may be, for example, 0.1mm to 2mm, and preferably not more than 1 mm. The upper end of reaction chamber 6 docks with the lower extreme of intercommunication route 10, and the upper end of intercommunication route 10 docks with stock solution chamber 7 to the upper end of reaction chamber 6 can indirectly communicate with stock solution chamber 7.

It should be understood that when the ammonia nitrogen detection component is put into use, the liquid storage cavity 7 and the reaction cavity 6 are not vertically arranged up and down due to the environment (fluctuating along with the water body to be detected) where the ammonia nitrogen detection component is located. The terms "upper" and "lower" are used herein only to indicate relative positional relationships.

The ammonia nitrogen detection part can comprise an electromagnetic valve and an electric control device, the electric control device controls the electromagnetic valve, the electromagnetic valve comprises a stopping piece 9, and the stopping piece 9 reciprocates under the action of magnetic force so as to enter and exit the communicating passage 10. The shape of the communication passage 10 is adapted to the stopper 9 so that the stopper 9 can be blocked, for example, to fill the communication passage 10 to isolate the reaction chamber 6 and the reservoir chamber 7.

Specifically, the stopper 9 may be a block having a large upper end and a small lower end, so that the stopper 9 can be quickly and safely introduced into the communication passage 10.

In addition, the stopping piece 9 disturbs the reaction reagent in the liquid storage cavity 7 in the reciprocating process, and promotes the reaction reagent in the liquid storage cavity 7 to enter the reaction cavity 6. Optionally, the ammonia nitrogen detection component may further comprise a diffusion promoting mechanism to promote diffusion. In one embodiment, the diffusion promoting mechanism is an electromagnetic oscillating member. The diffusion promoting mechanism may be provided separately from the reaction chamber and the liquid storage chamber, or may be provided inside the liquid storage chamber and operate each time the liquid storage chamber 7 and the reaction chamber 6 are communicated. When setting up in the stock solution intracavity portion, adopt devices such as inert protective sheath according to the circumstances to avoid the diffusion promotes the reaction of mechanism and the inside reactant in stock solution intracavity portion.

As shown in fig. 4a, the stop member 9 is at a low position to isolate the reaction chamber 6 from the reservoir chamber 7, and as shown in fig. 4b, the stop member 9 is at a high position to communicate the reaction chamber 6 with the reservoir chamber 7. In the service process of the ammonia nitrogen detection component, the stop piece 9 reciprocates along the vertical direction A so as to enable the reaction cavity 6 and the liquid storage cavity 7 to be in a communicated state and an isolated state circularly.

As shown in FIG. 4c, an electrical connection channel 11 may be provided between the reaction chamber 6 and the reservoir chamber 7, the electrical connection channel 11 being used for passing an electrical wire 111 connected to the electrode 8.

The reaction chamber 6 may be provided with an exhaust port, which may be formed, for example, by the end of the above-mentioned electrical connection channel 11, for exhausting hydrogen gas generated by the reaction in the reaction chamber 6. When the volume of the reaction chamber 6 is small, the air input is limited, and most of the generated hydrogen can be dispersed in the reaction reagent. When the volume of the reaction chamber 6 is larger, the amount of generated hydrogen is larger, and the hydrogen generated by the reaction can be discharged through an exhaust port (an electric connection channel), so that the obvious increase of the air pressure in the reaction chamber 6 is avoided.

In a modification of the present embodiment, the reaction chamber 6 may be directly butted with the reservoir chamber 7, that is, there is no communication passage 10, and the stopper 9 may be a cover perpendicular to the up-down direction a, so that the stopper 9 may cover the upper end of the reaction chamber 6 to isolate the reaction chamber 6 from the reservoir chamber 7.

The reaction cavity 6 and the liquid storage cavity 7 are arranged in the vertical direction A, so that the radial size of the ammonia nitrogen detection part is reduced.

The stopper 9 may be disposed in the reservoir 7, and the material of the stopper 9, the reaction chamber 6 and the reservoir 7 may be acid-resistant material, such as polyethylene, polytetrafluoroethylene, polyvinyl chloride or polypropylene.

Furthermore, the material of the stop member 9 may be a relatively low density, soft material, such as thermoplastic polyurethane elastomer rubber, thermoplastic elastomer material or rubber (excluding silicone rubber), etc.

As shown in fig. 5a and 5b, in another embodiment of the ammonia nitrogen detection component in the ammonia gas detection unit provided by the present disclosure, the structure of the ammonia nitrogen detection component is similar to that of the ammonia nitrogen detection component in the above-mentioned embodiment, and the differences mainly include the following aspects.

It should be noted that the "radial direction" of the functional chamber 12 is the same as the "radial direction" of the reaction chamber 6 as described below.

The ammonia nitrogen detection component further comprises a functional cavity 12, the functional cavity 12 is used for installing electronic components of the ammonia nitrogen detection component, the functional cavity 12 can be located above the reaction cavity 6, and the liquid storage cavity 7 can be located on the radial outer side of the reaction cavity 6 and the functional cavity 12. Specifically, the reservoir chamber 7 may surround the outer peripheries of the reaction chamber 6 and the function chamber 12, and the cross section (a section perpendicular to the up-down direction a) of the reservoir chamber 7 is annular. The reaction chamber 6 can be directly butted (communicated) with the reservoir chamber 7 in the radial direction thereof without passing through the communication passage 10.

The detection end of the conductivity detection electrode 8 is located in the reaction chamber 6, and a junction electrically connected to the outside may be located in the functional chamber 12. The functional cavity 12 and the reaction cavity 6 are arranged according to the position relation, so that the internal space of the ammonia nitrogen detection component can be fully utilized, the miniaturization of the ammonia nitrogen detection component is facilitated, and the power connection design of the electrode 8 is simplified.

The ammonia nitrogen detection part also comprises an electric valve, the electric control device controls the electric valve, and the electric valve comprises a stop part 9 which can reciprocate along the vertical direction A. The reaction chamber 6 is axially arranged along the vertical direction a, and the stopping member 9 may be a plate body which surrounds the reaction chamber 6 for one circle.

The embodiment of the electric valve and the communication passage 10 has lower positioning requirement, and is more beneficial to mechanical realization.

As shown in fig. 5a, the stop member 9 is at a low position to isolate the reaction chamber 6 from the reservoir chamber 7, and as shown in fig. 5b, the stop member 9 is at a high position to communicate the reaction chamber 6 with the reservoir chamber 7. In the service process of the ammonia nitrogen detection component, the stop piece 9 reciprocates along the vertical direction A so as to enable the reaction cavity 6 and the liquid storage cavity 7 to be in a communicated state and an isolated state circularly.

In a variant of this embodiment, the height of the reservoir 7 (the dimension in the up-down direction a) may also be less than or equal to the height of the reaction chamber 6, so that the reservoir 7 still surrounds the reaction chamber 6 radially outside the reaction chamber 6, but does not surround the functional chamber 12.

In the above-described embodiment, the reservoir 7 is located at the radial outer side (including the radial outer side or the radial inclined outer side) of the reaction chamber 6, and in other embodiments, the reservoir 7 may be located at other positions of the reaction chamber 6.

In other embodiments, the lower end of the reaction chamber 6 (the end for receiving ammonia gas) may be designed to be in a horn shape, so that ammonia gas can be more conveniently received.

It should be understood that in other embodiments provided by the present invention, a plurality (two or more) of reaction chambers 6 may be provided, such that a plurality of results tested by a plurality of reaction chambers 6 may be used to verify each other, enhancing the accuracy of the test.

Ammonia gas generating unit

In the present invention, the ammonia gas generating unit is a unit for generating ammonia gas. In some specific embodiments of the present invention, the ammonia gas generating unit is integrated with the ammonia gas detecting unit.

In addition, the ammonia gas generating unit is provided with one or more electrolysis electrodes, and the electrolysis electrodes electrolyze the water body entering the ammonia gas generating unit under the action of current to generate hydroxyl.

For the electrolysis electrode, the electrolysis electrode is used as an electrolysis cathode under the action of current to perform the following electrolysis reaction:

the pH value of the water body entering the ammonia gas generation unit is continuously increased by the continuous generation of electrolysis.

The electrolytic electrode is not particularly limited, and may be prepared using various cathode materials for electrolyzing water in the art. In some specific embodiments, at least one of a carbon material, a graphite material, or a metal material such as platinum, iridium, nickel, and the like may be used, and preferably, a graphite material or a platinum material may be used. The shape of the electrolytic electrode is also not particularly limited, and may be a sheet, a plate, a rod, or a film.

In addition, in some embodiments, in order to increase the reaction efficiency of the electrolysis cathode, an electrocatalyst layer may be formed on the surface of the electrolysis electrode, and for the electrocatalyst, those disclosed or already used in the field of hydrogen production from electrolysis of water may be used. The electrocatalyst can effectively reduce the electrolysis overpotential, so that the electrolysis reaction efficiency is improved.

The size of the electrode is adapted to the internal size of the ammonia gas generating unit, and in some preferred embodiments of the invention, the electrode can be a square, rectangle or other polygon with the maximum side length not exceeding 30 mm.

For the ammonia gas generation unit, it is needless to say that it also serves as a sampling device for the water body to be detected. The volume of the water in the ammonia gas generation unit is not particularly limited and may be adjusted according to the size of the equipment. Also, in some preferred embodiments, the water volume in the water storage container in the ammonia gas generation unit may be generally between 20ml and 100ml, for example, 20ml, 30ml, 40ml, 50ml, 60ml, 70ml, 80ml, 90ml, 100ml, or the like, from the viewpoint of convenience of calculation. In addition, for the ammonia gas generation unit, optionally, a switch or a valve may be provided, by which sampling and fixing of the water body sample are performed by opening or closing.

Furthermore, in some specific embodiments of the present invention, in the ammonia gas generating unit, a gas flow dividing means is provided to separate hydrogen gas generated from the surface of the electrolysis electrode from ammonia gas generated in the unit. The specific gas flow dividing means is not particularly limited, and typically, a flow guide plate may be provided above the electrolysis electrode (in the direction normal to the ground level) or a gas guide hole may be provided above the electrolysis electrode so that the hydrogen gas generated from the surface of the electrolysis electrode can be discharged from the ammonia gas generator with ease, and it is advantageous that such a flow guide plate or gas guide hole is close to the surface of the electrolysis electrode.

For the electrolysis electrode, the matching of the electrolysis counter electrode is needed in the work. The electrolysis counter electrode is not particularly limited as long as it is an electrode capable of oxidizing under the action of an electric current, and such an electrode is preferably an oxygen generating electrode in an apparatus for electrolyzing water. In some specific embodiments of the invention, an electrolysis counter electrode can be included in the ammonia nitrogen detection device of the invention, but is independent of the ammonia gas generation unit; in other specific embodiments of the present invention, the electrolysis counter electrode may be disposed at any other end away from the ammonia nitrogen detection apparatus of the present invention, for example, the counter electrode may be disposed in a ship away from the water body, a separate unit or device on the shore, or the like.

In addition, with respect to the electrolysis counter electrode of the present invention, the number thereof may be the same as or different from the number of the electrolysis electrodes. For example, the number of the electrolysis counter electrodes is less than the number of the electrolysis electrodes, and in this case, two or more electrolysis electrodes are connected in parallel. In addition, in other cases, one or more electrolysis counter electrodes are shared by the electrolysis electrodes in two or more ammonia nitrogen detection devices.

When the direct current supplies power to the electrolysis electrode and the electrolysis counter electrode, hydroxyl is generated in the ammonia gas generation unit of the invention to increase the pH value of the water body to be measured enclosed in the unit, the voltage between the electrolysis electrode (cathode) and the electrolysis counter electrode (anode) in electrolysis is not particularly limited, and the voltage range can be 1.3-30V, preferably 10-25V from the aspects of energy conservation and electrolysis efficiency.

There is no particular limitation on the energization time, which is related to the capacity of the water body in the ammonia gas generation unit and the electrolytic voltage. In some embodiments of the present invention, the energization time may be 10 to 120 seconds, preferably 15 to 40 seconds, that is, a sufficient concentration of the electrolytic alkaline substance may be obtained; in other specific embodiments, the pH of the water body to be detected in the ammonia gas generation unit is raised to 12 or more, preferably 12.5 or more, and more preferably 13 or more by electrolysis of the electrolysis electrode. With the gradual rise of the pH value, the ammonium ions in the water body to be detected are gradually converted into ammonia gas under the high-alkalinity condition, and overflow out of the water body, and contact with the ammonia gas sensitive material through the semi-permeable membrane and the gas inlet channel.

Sensitivity of detection

Compared with the prior art, the ammonia nitrogen detection equipment provided by the invention can provide excellent detection precision and detection sensitivity under the condition of not using an additional alkaline substance or alkaline reagent.

In some embodiments of the invention, the detection limit for ammonium ions of the invention may be up to 1mg/L, and in some embodiments even up to 0.5mg/L, and the (linear) range of detection may be from 5 to 1000 mg/L.

In addition, the ammonia nitrogen detection equipment provided by the invention at least comprises the ammonia gas detection unit and the ammonia gas generation unit, and can also comprise one or more of the following structures or units under any necessary condition.

Pre-electrolysis unit

In some specific embodiments of the present invention, the ammonia gas generation unit in the ammonia nitrogen detection device further comprises a pre-electrolysis unit.

The pre-electrolysis unit can be arranged in the ammonia gas generation unit and is communicated with other spaces in the ammonia gas generation unit through closing or opening of a controllable valve. In this case, the other space inside the ammonia gas generation unit may be used as a main space of the ammonia gas generation unit, and the space inside the pre-electrolysis unit may be used as an auxiliary space of the ammonia gas generation unit. At least one electrolysis electrode is arranged in the auxiliary space to electrolyze the water body entering the auxiliary space to generate OH under the condition of electrifying current^-. At this time, the auxiliary space is not communicated with the main space of the ammonia gas generating unit, that is, the valve is in a closed state. And alkaline liquid obtained by electrolysis is stored in the auxiliary space, and when water detection is required, the alkaline liquid is released into the main space of the ammonia gas generation unit by opening a valve. Therefore, in such an embodiment of the present invention, the alkaline liquid can be generated as a reserve by pre-electrolysis and can be released when the water body detection is started, so as to achieve the purposes of quick response and quick detection.

In addition, the pre-electrolysis unit described above may be additionally located outside the ammonia gas generation unit and be in communication with the ammonia gas generation unit by closing or opening a controllable valve/line. In this case, the internal space of the ammonia gas generation unit may serve as a main space of the ammonia gas generation unit, and the internal space of the pre-electrolysis unit may serve as an auxiliary space of the ammonia gas generation unit.

Further, the volume ratio between the main space and the (additional) auxiliary space in the above-described ammonia gas generation unit is not particularly limited. For example, in some specific embodiments, the volume ratio of the main space to the auxiliary space is 1:1 to 10:1, preferably 2:1 to 7:1, and more preferably 3:1 to 5: 1.

In other particular embodiments of the invention, at least one electrolysis electrode may be provided in both the main space and the (additional) auxiliary space of the ammonia gas generation unit described above. On one hand, when the water quality of the water body is detected, the alkaline liquid in the auxiliary space can be released into the main space through the valve, and meanwhile, the electrolytic electrode in the main space can still be started to work, so that the pH value in the detected water body can be rapidly increased; on the other hand, the arrangement of more than one electrolysis electrode in each of the main space and the auxiliary space can prevent the failure of the detection due to the failure of the electrode operation in one of the spaces.

Counter electrode and self-cleaning

In some specific embodiments of the present invention, a counter electrode may be further disposed in the ammonia gas generating unit. The "counter electrode" of the present invention is different from the above-mentioned electrolysis counter electrode and is capable of generating H by an electrolytic reaction under a current-applying condition⁺The electrode of (1).

These counter electrodes may be provided in one or more of the above-described ammonia gas generation units. In addition, when the main space and the auxiliary space are present, one or more counter electrodes described above may be provided in each of these spaces. In addition, in other specific embodiments of the present invention, the electrolysis electrode itself can be used as a counter electrode as long as it is connected with a reverse current.

Considering that the electrolytic electrode of the present invention generates OH under the current condition^-While taking into account the fact that the presence of some metal ions in the body of water being tested is liable to cause the deposition of precipitates or other types of impurities, the electrolysis of the counter-electrode is therefore used to generate H whenever required⁺Thereby helping to dissolve or eliminate these undesirable deposits so as to act as a self-cleaning action for the ammonia gas generating unit.

Water body and filter unit

The ammonia nitrogen detection equipment is suitable for detecting or monitoring the nitrogen content in various water bodies. There is no particular limitation on the water body. In some embodiments of the present invention, the water body may be river water, lake water, seawater, domestic or industrial wastewater, or one of purified domestic or industrial wastewater.

Various complicated conditions are usually encountered in the sampling of the water body, and undesirable solid or microbial impurities may cause adverse effects on the water body sampling and subsequent monitoring, so that the detection precision or effectiveness of the ammonia nitrogen detection equipment is reduced.

Therefore, in some specific embodiments of the invention, the water body after filtration treatment can enter the water storage container in the ammonia gas generation unit at each sampling time by placing the filtration unit in front of the ammonia gas generation unit.

Additional alkaline substance backup unit

As mentioned above, the ammonia nitrogen detection device provided by the invention does not need to add alkaline substances due to the existence of the electrolysis electrode. It goes without saying that, in order to provide an effective redundant design, optionally, additional spare units for alkaline substance can also be provided.

In the unit, a volume of solid or liquid alkaline substance, such as an alkali metal hydroxide or the like, may be stored. When the working efficiency of an electrolytic electrode of certain ammonia nitrogen detection equipment is reduced or the working is unstable, the generation of ammonia gas can be assisted by the release of the alkaline substances. Thus, accurate detection data can be stably and continuously provided even in an unexpected situation, and since the above situation is a small probability event, no significant burden is imposed on the maintenance of the apparatus.

Floating auxiliary unit

When the ammonia nitrogen monitoring equipment is used for detecting the water body, the ammonia nitrogen monitoring equipment can be placed in the water body to be detected in a floating, submerging or semi-submerging mode. In the placing mode, at least the ammonia gas generating unit in the ammonia nitrogen detection equipment is immersed in the water body, so that the water body can be conveniently sampled at any time.

The above-mentioned placement of the detection device can be achieved by a floating auxiliary unit. In some specific embodiments of the present invention, the floating auxiliary unit has a frame for fixing the ammonia nitrogen detection device, and optionally, may also have an adjustable floating weight, and the shape and/or weight of the floating weight can be adjusted to adjust the posture of the ammonia nitrogen monitoring device and serve as a stabilizing device, especially serving as a balance or an anchor under the condition of detection in a flowing water body.

Power supply unit

As mentioned above, the invention carries out the electrolysis and detection of the water body to be detected by electrifying the electrolysis electrode and the electrolysis counter electrode with direct current.

For the source of the direct current, the power may be supplied by an independent power supply unit. In some particular embodiments of the invention, such a unit may be a power generation facility located at a site remote from the (or each) ammonia nitrogen detection facility. The (each) ammonia nitrogen detection device is independently supplied with direct current by the power generation device.

In other specific embodiments of the invention, the ammonia nitrogen detection device may have a self-powered unit, for example, such a self-powered unit may be integral with the ammonia nitrogen detection device or connected via a wire. In some exemplary embodiments, such power supply units may be derived from clean energy sources such as solar energy, wind energy, water flow energy, and the like. In any case, when the power supply unit is a self-powered unit, an energy storage unit can be arranged in the ammonia nitrogen detection device, and such an energy storage unit can be based on a battery capable of being repeatedly charged and discharged, such as a lithium ion secondary battery.

Temperature compensation unit

In the invention, ammonia nitrogen detection equipment is used for detecting the water body to be detected, and the detection is favorably carried out under the normal temperature condition of the water body under the normal condition. The normal temperature of the water body is a concept related to the geographical position, and the normal temperature can be between 5 and 25 ℃ according to different latitudes where different water bodies are located.

Under some conditions, the temperature of the water body may be too low, or the temperature change is large in different months or seasons for the same water body, which is unfavorable for the detection accuracy and stability of the ammonia nitrogen detection device. Therefore, the accuracy and the smoothness of detection can be improved by using the temperature compensation unit.

In some specific embodiments, for the temperature compensation device, the ammonia nitrogen detection device may be heated by the power provided by the above power supply to maintain the device operating under proper and stable temperature conditions.

In other specific embodiments, under the condition that the temperature of the water body to be detected is too low, the ammonia nitrogen detection device is heated within a period of time before water quality detection is performed, for example, 1-30 min before the detection device is started, preferably within 2-10 min, and especially the water body to be detected which enters the ammonia gas generation unit in the device is heated.

In addition, other functions of the temperature compensation unit also include heating the ammonia gas detection unit when necessary, and the unit is heated, so that the temperature of the ammonia gas sensitive material in the unit is increased, and the ammonia gas adsorbed on the ammonia gas sensitive material can be desorbed by the method after the detection is finished, thereby being beneficial to the rapid regeneration of the ammonia gas sensitive material and the next detection.

SignalTransmitting or receiving unit

The ammonia nitrogen detection equipment optionally comprises a signal transmitting or receiving unit.

In some specific embodiments of the present invention, when a plurality of ammonia nitrogen detection devices are used to detect a water body, each ammonia nitrogen detection device may perform wireless transmission of information or reception of instructions through a signal transmitting or receiving unit.

The kind of such signal transmitting or receiving unit is not particularly limited, and may include, but is not limited to, the following devices:

the position information device can provide position information of the detection equipment according to positioning systems such as a global satellite positioning system, a Beidou navigation system and the like, and is particularly favorable for maintenance, recovery or arrangement of the equipment;

the state information device can provide information such as the self state (such as residual electric quantity, fault information, detection equipment number, energy utilization rate and timestamp) of the ammonia nitrogen detector through various sensors;

the information transmission device can transmit various information based on Bluetooth or a wireless network, such as a Wi-Fi network, a 4G network or a 5G network;

the instruction receiving and micro-control device is used for receiving various instructions to perform actions such as water body monitoring, position or attitude adjustment and the like.

< second aspect >

In a second aspect of the present invention, a method for detecting the content of nitrogen elements, especially ammonium ions, in a water body is provided, in which one or more ammonia nitrogen detection devices described in the above < first aspect > are used to detect the water body to be detected.

Typically, for the detection of bodies of water in open waters, it is advantageous for the detection apparatus to have a range of multiple position distributions. In some preferred embodiments of the present invention, it is advantageous to use more than 1, preferably more than 2 ammonia nitrogen detection devices of the present invention per square kilometer of the water surface area of the water body.

In other cases, the detection device may be arranged on a per kilometer length basis for the detected river flow field, for example, more than 1, preferably more than 2 ammonia nitrogen detection devices of the present invention may be advantageously used on a per kilometer length basis of the river.

The multiple detection devices simultaneously provide data of water quality conditions of water bodies at different positions in the open water area, so that the assessment of the whole water quality and the water quality change of the water body in the water area is facilitated.

In addition, the ammonia nitrogen detection equipment provided by the invention is particularly suitable for online detection and monitoring of various water bodies. Through the information processing system, the terminal display system and the control system, and optionally in combination with other water quality detection units (such as a heavy metal content detection unit, a phosphorus content detection unit, a Chemical Oxygen Demand (COD) detection unit and the like), the water quality detection of the water body to be detected can be carried out on line in real time.

Examples

Hereinafter, the technical solution of the present invention will be specifically described by specific examples.

Example 1

Detection device：

Ammonia nitrogen detection equipment is shown in figure 2, and comprises:

ammonia gas sensitive material (built-in electrode for conductivity detection);

electrolysis electrode (cathode);

an electrolytic counter electrode (anode);

semi-permeable membrane

The materials for the above 1 '-4' are commercially available. Meanwhile, the ammonia nitrogen detection device is provided with a shell (not shown), and the electrolysis electrode 2 is arranged in an ammonia gas generation unit enclosed by the shell through a fixing device (not shown). Further, the ammonia gas generating unit has an inlet and an outlet (not shown) from the outside. In operation, dc power is provided by dc power supply equipment (not shown).

The cathode is 3mm away from the semi-permeable membrane, and the distance between the cathode and the anode is 3 cm. The voltage of the direct current between the cathode and the anode was 24V.

Conditions of test solution：

Initial conductivity inside the ammonia sensitive material: 80 +/-5 mu S/cm

The pH value of the detection solution is 6-8

Detecting the liquid temperature: 24-25 deg.C

With (NH)₄)₂SO₄Preparing standard ammonia ion solution for reference substances, wherein the contents of prepared ammonia ions are as follows: 5mg/L, 10mg/L, 25mg/L, 50mg/L and 100mg/L of standard solutions.

Test procedure：

And (3) placing the detection equipment in a test solution with certain concentration.

The test starts to time from the electrification of the anode and the cathode (at the moment, 0 second), the electrification time is 30 seconds, and the response curve of the conductivity detection electrode in the ammonia gas sensitive material within 0-90 seconds is recorded, so that the slope value (conductivity change rate) corresponding to the test solution is obtained.

The slope values of each test solution were plotted to obtain a curve as shown in the following graph (see FIG. 3). Fitting the curve to obtain the relation between the conductivity change rate and the ammonia nitrogen concentration. The correlation coefficient is verified to be R of 0.998.

It should be noted that, although the technical solutions of the present invention are described by specific examples, those skilled in the art can understand that the present disclosure should not be limited thereto.

Having described embodiments of the present disclosure, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen in order to best explain the principles of the embodiments, the practical application, or improvements made to the technology in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.

Industrial applicability

The ammonia nitrogen detection equipment provided by the invention can be industrially used for water quality detection of various water bodies.

Claims

1. The utility model provides an ammonia nitrogen check out test set which characterized in that includes:

an ammonia gas detection unit;

an ammonia gas generation unit;

2. The apparatus according to claim 1, wherein a semi-permeable membrane is provided between the ammonia gas generating unit and the ammonia gas detecting unit, and the semi-permeable membrane is impermeable to liquid molecules.

3. The apparatus according to claim 1 or 2, characterized in that the ammonia gas generation unit comprises one or more of the electrolysis electrodes.

4. The apparatus according to any one of claims 1 to 3, wherein the water body to be measured in the ammonia gas generation unit is one selected from river water, lake water, seawater, domestic or industrial wastewater, or purified domestic or industrial wastewater.

5. The apparatus according to any one of claims 1 to 4, wherein the ammonia gas generating unit comprises a pre-electrolysis unit, and at least one electrolysis electrode is placed in the ammonia gas generating unit at least in the pre-electrolysis unit.

6. The equipment according to any one of claims 1 to 5, wherein the ammonia gas generation unit further comprises a counter electrode, and the counter electrode electrolyzes the water body to be tested entering the ammonia gas generation unit under the condition of electrifying current to generate H⁺。

7. The equipment according to any one of claims 1 to 6, wherein the ammonia nitrogen detection unit comprises an ammonia nitrogen detection component, the ammonia nitrogen detection component comprises a reaction chamber and a liquid storage chamber, and the volume of the liquid storage chamber is larger than that of the reaction chamber.

8. The apparatus of claim 7, wherein the reaction chamber includes a conductivity responsive electrode therein.

9. The apparatus according to any one of claims 1 to 7, wherein the ammonia gas detection unit calculates NH in the water body to be detected based on changes in optical, electrical or chemical parameters₄ ⁺And (4) concentration.

10. The equipment according to any one of claims 1 to 9, wherein the ammonia nitrogen detection equipment further comprises a temperature compensation unit.

11. The apparatus of any one of claims 1 to 10, wherein the current is direct current.

12. An apparatus for detecting water quality of a body of water, comprising one or more apparatus according to any one of claims 1 to 11.

13. A method for detecting the water quality of a river water body or a lake water body on line, which is characterized by comprising the step of detecting NH in the river water body or the lake water body by using the device according to any one of claims 1-12₄ ⁺The concentration of (c).

14. A method according to claim 13, wherein more than 2 apparatus according to any one of claims 1 to 12 are used per square kilometre of surface area of the body of water.