A fully automatic chemical oxygen demand analyzer based on the dichromate method

Abstract

The invention discloses a fully automatic chemical oxygen demand analyzer based on a dichromate method, comprising: a digestion module, a condensation module, a lower liquid addition module, an upper liquid addition module, a stirring module and a titration module, which automatically realizes the digestion, condensation, liquid addition, stirring and titration of a sample. The fully automatic chemical oxygen demand analyzer based on a dichromate method provided by the invention realizes the fully automatic detection of CODCr, and the detection conditions are stable and the applicability is strong.

Description

Technical Field

[0001] The invention relates to the technical field of chemical analysis and detection equipment, in particular to a full-automatic chemical oxygen demand analyzer based on a dichromate method. Background Art

[0002] Chemical oxygen demand by dichromate method, referred to as CODCr, measures the amount of reducing substances that need to be oxidized in water and is an important indicator of the degree of water pollution. Too high CODCr in water indicates serious organic pollution, so it is also an important parameter in the fields of environmental testing and wastewater treatment. The national standard test method referred to is "Determination of Chemical Oxygen Demand of Water Quality by Dichromate Method" (HJ 828-2017).

[0003] The CODCr detection process is complex, and many reagents are used. The reagents are corrosive and toxic, and the detection process is extremely sensitive to conditions. The current equipment used for CODCr detection on the market has many problems, such as the detection process still relies on manual operation, low degree of automation, unstable detection conditions, and inability to detect in large quantities. Therefore, achieving fully automated detection of CODCr is a technical problem that needs to be solved urgently in the water quality testing industry. Summary of the invention

[0004] The purpose of the present invention is to provide a fully automatic chemical oxygen demand analyzer based on the dichromate method, which is used to realize the fully automatic detection of CODCr, and has stable detection conditions and strong applicability.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] A fully automatic chemical oxygen demand analyzer based on the dichromate method, comprising: a digestion module, a condensation module, a lower liquid adding module, an upper liquid adding module, a stirring module and a titration module;

[0007] Wherein, the digestion module includes two front and rear digestion units, each of which includes a heating panel, a heating unit and a plurality of sample cups, the upper surface of the heating panel is provided with a plurality of marking positions and a plurality of digestion positions, the marking positions and the digestion positions are both provided with sample cups with magnets inside, the top of the sample cup is provided with an interface, the sample cups of the two digestion units at the digestion positions constitute a sample cup array, the sample cups at the digestion positions are used to hold samples, the sample cups at the marking positions are used to calibrate the ammonium ferrous sulfate solution, and the heating unit is located below the heating panel;

[0008] The condensation module includes two front and rear condensation units, each of which includes a condensation tube bracket, a lifting mechanism and a plurality of condensation tubes. The condensation tube bracket is arranged above the lifting mechanism, and a plurality of condensation tubes are arranged on the condensation tube bracket. The lifting mechanism drives the condensation tube bracket to move up and down, and drives the plurality of condensation tubes to move up and down; a sealing ring, a spring and a fixing ring are arranged on the condensation tube, and the fixing ring is fixedly installed on the condensation tube, the spring is sleeved on the condensation tube and abuts between the condensation tube bracket and the fixing ring, and the sealing ring is arranged on the spherical joint at the bottom of the condensation tube; the condensation tubes of the two condensation units constitute a condensation tube array, the condensation tube array corresponds to the sample cup array and is arranged directly above the sample cup array, and the spherical joint at the bottom of the condensation tube is adapted to the sample cup interface;

[0009] The lower liquid adding module comprises a lower sliding rail, a lower sliding seat, a lower rotating mechanism and a lower rotating arm, wherein the lower sliding seat is slidably arranged on the lower sliding rail, and the lower rotating arm is rotatably arranged on the lower sliding seat through the lower rotating mechanism, and the front end of the lower rotating arm is provided with a pipe three for adding a mercuric sulfate solution, a pipe four for adding a high-concentration potassium dichromate solution and a pipe five for adding a low-concentration potassium dichromate solution, and the lower sliding seat moves linearly on the lower sliding rail through the lower driving mechanism, driving the lower rotating arm to move linearly, and at the same time, the lower rotating mechanism is used to drive the lower rotating arm to rotate, driving the liquid outlets of the pipes three, four and five to align with the inlet of the sample cup;

[0010] The upper liquid adding module is installed directly above the condensing module and is used to add silver sulfate sulfuric acid solution and ultrapure water into the condensing tube;

[0011] The stirring module comprises two front and rear stirring units, the two stirring units are respectively arranged on the lower slide seat, and the stirring module drives the magnet to rotate to stir;

[0012] The titration module includes a color monitoring unit, which is arranged on the lower rotary arm and is used to monitor the color change of the liquid in the sample cup. The front end of the lower rotary arm is provided with a pipeline 6 for adding ferrous sulfate solution, a pipeline 7 for adding high-concentration ammonium ferrous sulfate solution, a pipeline 8 for adding low-concentration ammonium ferrous sulfate solution, a pipeline 9 for adding sulfuric acid solution and a pipeline 10 for adding ultrapure water. The lower slide seat moves linearly on the lower slide rail through the lower driving mechanism, driving the lower rotary arm to move linearly. At the same time, the lower rotating mechanism drives the lower rotary arm to rotate, driving the liquid outlets of the pipelines 6, 7, 8, 9 and 10 to align with the inlet of the sample cup.

[0013] Optionally, each of the digestion units further includes a cooling fan, which is disposed at a position of a sample cup directly opposite to the digestion position; each of the condensation units further includes a condensation fan, which is disposed at a position directly opposite to the condensation tube.

[0014] Optionally, a waste discharge position is further provided on the upper surface of the heating panel, and a sample cup is provided at the waste discharge position for collecting waste liquid discharged from the liquid outlets of pipeline three, pipeline four, pipeline five, pipeline six, pipeline seven, pipeline eight, pipeline nine and pipeline ten.

[0015] Optionally, the upper liquid adding module includes an upper slide rail, an upper slide seat, an upper rotating mechanism and an upper cantilever, the upper slide seat is slidably set on the upper slide rail, the upper rotating arm can be rotatably set on the upper slide seat through the upper rotating mechanism, the front end of the upper cantilever is provided with a pipe 1 for adding silver sulfate sulfuric acid solution and a pipe 2 for adding ultrapure water, the upper slide seat moves linearly on the upper slide rail through the upper driving mechanism, driving the upper cantilever to move linearly, and at the same time the upper rotating mechanism drives the upper cantilever to rotate, driving the liquid outlets of pipe 1 and pipe 2 to align with the inlet of the condenser.

[0016] Optionally, the upper liquid adding module further includes a waste liquid bottle for collecting waste liquid discharged from the liquid outlets of pipeline one and pipeline two.

[0017] Optionally, the stirring unit includes a magnet seat and a motor, the motor is arranged below the lower sliding seat, the magnet seat is arranged above the lower sliding seat, a magnet is provided on the magnet seat, the output shaft of the motor passes through the lower sliding seat and is connected to the magnet seat, the lower sliding seat moves horizontally, driving the magnet seat and the motor to move horizontally, and at the same time the motor drives the magnet seat to rotate, driving the magnet to rotate for stirring.

[0018] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects: the fully automatic chemical oxygen demand analyzer based on the dichromate method provided by the present invention replaces the manual detection method with an automated detection process, realizes fully automated detection of CODCr, ensures the consistency and reliability of the detection, eliminates the errors caused by the manual detection method, and has stable detection conditions, which is convenient for batch detection, greatly reduces labor intensity, and has strong applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0020] Figure 1 It is a left view of a fully automatic chemical oxygen demand analyzer based on a dichromate method according to an embodiment of the present invention;

[0021] Figure 2 It is a front view of a fully automatic chemical oxygen demand analyzer based on the dichromate method according to an embodiment of the present invention.

[0022] Explanation of reference numerals: 1.1, sample cup; 1.2, heating panel; 1.3, heating unit; 1.4, cooling fan; 1.5, digestion position; 1.6, waste discharge position; 1.7 marking position; 2.1, condenser; 2.2, sealing ring; 2.3, spring; 2.4, fixing ring; 2.5, condenser bracket; 2.6, condenser fan; 2.7, lifting mechanism; 3.1, upper slide rail; 3.2, upper slide seat; 3.3, upper rotating mechanism; 3.4, upper rotating mechanism arm; 3.5, pipeline one; 3.6, pipeline two; 3.7, waste liquid bottle; 4.1, lower slide rail; 4.2, lower slide seat; 4.3, lower rotating mechanism; 4.4, lower rotary arm; 4.5, pipeline three; 4.6, pipeline four; 4.7, pipeline five; 5.1, magnet; 5.2, magnet seat; 5.3, motor; 6.1, color monitoring unit; 6.2, pipeline six; 6.3, pipeline seven; 6.4, pipeline eight; 6.5, pipeline nine; 6.6, pipeline ten. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] The purpose of the present invention is to provide a fully automatic chemical oxygen demand analyzer based on the dichromate method, which is used to realize the fully automatic detection of CODCr, and has stable detection conditions and strong applicability.

[0025] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] like Figure 1 As shown, the fully automatic chemical oxygen demand analyzer based on the dichromate method provided by the embodiment of the present invention includes: a digestion module, a condensation module, a lower liquid adding module, an upper liquid adding module, a stirring module and a titration module;

[0027] Wherein, the digestion module comprises two front and rear digestion units, each of which comprises a heating panel 1.2, a heating unit 1.3 and a plurality of sample cups 1.1, the upper surface of the heating panel 1.2 is provided with a plurality of marking positions 1.7 and a plurality of digestion positions 1.5, the marking positions 1.7 and the digestion positions 1.5 are both provided with sample cups 1.1 with magnets inside, the top of the sample cups 1.1 are provided with interfaces, the sample cups 1.1 of the two digestion units at the digestion positions 1.5 form a linear sample cup array, the sample cups 1.1 at the digestion positions 1.5 are used to hold samples, the sample cups 1.1 at the marking positions 1.7 are used for the calibration of ammonium ferrous sulfate solution, the sample cups 1.1 at the front and rear marking positions 1.7 are used for making parallel double samples, and the heating unit 1.3 is located below the heating panel 1.2, and is used to heat the sample cups 1.1 on the digestion positions 1.5;

[0028] The condensation module includes two front and rear condensation units, each of which includes a condensation tube bracket 2.5, a lifting mechanism 2.7 and a plurality of condensation tubes 2.1. The condensation tube bracket 2.5 is arranged above the lifting mechanism 2.7, and a plurality of condensation tubes 2.1 are arranged on the condensation tube bracket 2.5. The lifting mechanism 2.7 drives the condensation tube bracket 2.5 to move up and down, and drives a plurality of condensation tubes 2.1 to move up and down, so as to realize automatic docking and detachment between the condensation tube array and the sample cup array; a sealing ring 2.2, a spring 2.3 and a fixing ring 2.4 are arranged on the condensation tube 2.1, and the fixing ring 2.4 is fixedly installed on the condensation tube 2.1, and the spring 2.3 can be slidably mounted on the condensation tube 2.1 and abuts between the condensation tube bracket 2.5 and the fixing ring 2.4, and the sealing ring 2.2 is arranged on the spherical joint at the bottom of the condensation tube 2.1; the condensation tubes 2.1 of the two condensation units constitute a linear condensation tube array, and the The condenser array corresponds to the sample cup array and is arranged directly above the sample cup array (the number of condensers 2.1 in each condensation unit is consistent with the number of sample cups 1.1 accommodated in the digestion position 1.5, and each condenser 2.1 corresponds one-to-one to the sample cup 1.1 on the digestion position 1.5 directly below), the condenser 2.1 is a hollow glass tube body, and a water-cooled container is designed at the upper end, which is filled with coolant (the condenser 2.1 can be air-cooled or water-cooled), and the spherical joint at the bottom of the condenser 2.1 is adapted to the interface of the sample cup 1.1; when the condenser 2.1 is docked with the sample cup 1.1, it plays a sealing role; when the condenser module moves downward, the condenser 2.1 is docked with the sample cup 1.1, the condenser 2.1 stops moving downward, and the condenser bracket 2.5 continues to move downward for a distance, and the compression spring 2.3 generates pressure, and acts on the sealing ring 2.2 through the fixing ring 2.4 and the condenser 2.1, plays a compression and sealing role, and strengthens the sealing effect;

[0029] The lower liquid adding module comprises a lower slide rail 4.1, a lower slide seat 4.2, a lower rotating mechanism 4.3 and a lower rotary arm 4.4. The lower slide seat 4.2 is slidably arranged on the lower slide rail 4.1. The lower rotary arm 4.4 is rotatably arranged on the lower slide seat 4.2 through the lower rotating mechanism 4.3. A pipe 3 4.5 for adding mercuric sulfate solution, a pipe 4 4.6 for adding high-concentration potassium dichromate solution and a pipe 5 4.7 for adding low-concentration potassium dichromate solution are arranged at the front end of the lower rotary arm 4.4. The lower slide seat 4.2 moves linearly on the lower slide rail 4.1 through the lower driving mechanism, driving the lower rotary arm 4.4 to move linearly. At the same time, the lower rotating mechanism 4.3 is used to drive The lower rotary arm 4.4 is driven to rotate, driving the liquid outlets of the pipe three 4.5, the pipe four 4.6 and the pipe five 4.7 to align with the inlet of the sample cup 1.1; the lower rotary mechanism 4.3 is used to rotate the lower rotary arm 4.4, which is installed on the lower slide seat 4.2, and the lower rotary mechanism 4.3 moves synchronously with the lower slide seat 4.2; the lower rotary arm 4.4 is installed on the lower rotary mechanism 4.3, and under the action of the lower slide seat 4.2 and the lower rotary mechanism 4.3, the pipe three 4.5, the pipe four 4.6 and the pipe five 4.7 follow the lower rotary arm 4.4 to move synchronously, and its liquid outlet adds liquid to the front and rear rows of sample cups 1.1 arrays, and its liquid inlet is connected to the respective solution delivery device and liquid storage container;

[0030] The upper liquid adding module is installed directly above the condensing module and is used to add silver sulfate sulfuric acid solution and ultrapure water into the condensing tube 2.1;

[0031] The stirring module includes two front and rear stirring units, and the two stirring units are respectively arranged on the lower slide seat 4.2. The stirring module drives the magnet to rotate to stir;

[0032] The titration module comprises a color monitoring unit 6.1, which is arranged on the lower rotary arm 4.4 and is used to monitor the color change of the liquid in the sample cup 1.1. The front end of the lower rotary arm 4.4 is provided with a pipeline 6.2 for adding ferrous sulfate solution, a pipeline 7.3 for adding high-concentration ammonium ferrous sulfate solution, a pipeline 8.4 for adding low-concentration ammonium ferrous sulfate solution, a pipeline 9.5 for adding sulfuric acid solution and a pipeline 10.6 for adding ultrapure water. The lower slide seat 4.2 is driven by a lower drive motor. The lower rotary mechanism 4.3 moves linearly on the lower slide rail 4.1, driving the lower rotary arm 4.4 to move linearly, and at the same time, the lower rotary mechanism 4.3 drives the lower rotary arm 4.4 to rotate, driving the liquid outlets of the pipe 6.2, the pipe 7.3, the pipe 8.4, the pipe 9.5 and the pipe 10.6 to align with the inlet of the sample cup 1.1, and the pipe 6.2, the pipe 7.3, the pipe 8.4, the pipe 9.5 and the pipe 10.6 move synchronously with the lower rotary arm 4.4, and their liquid inlets are connected to the conveying devices and liquid storage containers of their respective solutions. When the lower rotary arm 4.4 moves to the upper side of a sample cup 1.1 for adding liquid, the stirring module simultaneously moves to the bottom of the sample cup 1.1, and the color monitoring unit 6.1 moves to the side of the sample cup 1.1, and the sample cup 1.1 can be stirred, added, and monitored at the same time to realize the titration function.

[0033] Each of the digestion units also includes a cooling fan 1.4, which is arranged at the position of the sample cup 1.1 opposite to the digestion position 1.5, and is used to quickly cool the sample cup 1.1 after heated digestion; each of the condensation units also includes a condensation fan 2.6, which is arranged at the position opposite to the condensation tube 2.1, and is used to cool the condensation tube 2.1 and enhance the condensation effect.

[0034] A waste discharge position 1.6 is also provided on the upper surface of the heating panel 1.2, and a sample cup 1.1 is provided at the waste discharge position 1.6 for collecting waste liquid discharged from the outlets of pipeline three 4.5, pipeline four 4.6, pipeline five 4.7, pipeline six 6.2, pipeline seven 6.3, pipeline eight 6.4, pipeline nine 6.5 and pipeline ten 6.6.

[0035] The upper liquid adding module includes an upper slide rail 3.1, an upper slide seat 3.2, an upper rotating mechanism 3.3 and an upper cantilever 3.4. The upper slide seat 3.2 is slidably arranged on the upper slide rail 3.1. The upper rotating arm 3.4 can be rotatably arranged on the upper slide seat 3.2 through the upper rotating mechanism 3.3. A pipe 1 3.5 for adding silver sulfate sulfuric acid solution and a pipe 2 3.6 for adding ultrapure water are provided at the front end of the upper cantilever 3.4. The upper slide seat 3.2 moves linearly on the upper slide rail 3.1 through the upper driving mechanism, driving the upper cantilever 3.4 to move linearly. At the same time, the upper rotating mechanism 3.3 drives the upper cantilever 3.4 to rotate, driving the liquid outlets of the pipe 1 3.5 and the pipe 2 3.6 to align with the inlet of the condenser 2.1. Under the action of the upper slide 3.2 and the upper rotating mechanism 3.3, liquid is added to the front and rear rows of condenser tube arrays through the liquid outlets of pipe 1 3.5 and pipe 2 3.6. The upper rotating mechanism 3.3 is used to rotate the upper rotary arm 3.4, which is installed on the upper slide 3.2. The upper rotating mechanism 3.3 moves synchronously with the upper slide 3.2. The pipe 1 3.5 and pipe 2 3.6 move synchronously with the upper rotary arm 3.4, and their liquid outlets are aligned with the inlet of the condenser 2.1, and their liquid inlets are connected to the conveying devices and liquid storage containers of their respective solutions.

[0036] The upper liquid adding module further comprises a waste liquid bottle 3.7 for collecting waste liquid discharged from the liquid outlets of the pipeline 1 3.5 and the pipeline 2 3.6.

[0037] The stirring unit includes a magnet seat 5.2 and a motor 5.3. The motor 5.3 is arranged below the lower sliding seat 4.2. The magnet seat 5.2 is arranged above the lower sliding seat 4.2. A magnet 5.1 is arranged on the magnet seat 5.2. The output shaft of the motor 5.3 passes through the lower sliding seat 4.2 and is drivingly connected to the magnet seat 5.2. The lower sliding seat 4.2 moves horizontally, driving the magnet seat 5.2 and the motor 5.3 to move horizontally. At the same time, the motor 5.3 drives the magnet seat 5.2 to rotate, driving the magnet to rotate for stirring.

[0038] In this embodiment, taking the detection of high-concentration samples as an example, the method of using the dichromate method fully automatic chemical oxygen demand analyzer is as follows:

[0039] 1) Start the analyzer, the analyzer self-checks and returns to zero, the condensation module is in the raised state, the upper slide 3.2 and the lower slide 4.2 are in the left zero position, and the upper rotary arm 3.4 and the lower rotary arm 4.4 rotate to be parallel to the row surface of the sample cup 1.1;

[0040] 2) The inspector places the sample cup 1.1 containing the sample to be tested and the magnet in the digestion position 1.5, and places the sample cup 1.1 containing the magnet in the marking position 1.7, clicks to start the test, and the analyzer enters the fully automatic test process;

[0041] 3) The lower rotary arm 4.4 rotates and moves to above the waste discharge position 1.6, so that the liquid outlet corresponds to the sample cup 1.1 at the waste discharge position 1.6, and the liquid outlet discharges liquid in turn, squeezing out the air in the corresponding pipeline;

[0042] 4) The lower rotary arm 4.4 rotates and moves to the top of the sample cup 1.1 in the digestion position 1.5, and the stirring module moves to the bottom of the sample cup. The stirring module is started, and the pipeline 3 4.5 and the pipeline 4 4.6 add mercuric sulfate solution and potassium dichromate solution to the sample cups 1.1 in the front and rear rows containing samples. During the liquid addition process, the stirring module drives the magnet in the sample cup 1.1 to rotate to realize the stirring function. After all the sample cups 1.1 in the digestion position 1.5 are filled with liquid in turn, the lower seat 4.2 moves left to the zero position, and the lower rotary arm 4.4 rotates to be parallel to the row surface of the sample cups 1.1, and the stirring function is turned off.

[0043] 5) The lifting mechanism 2.7 is started, the condensation module moves downward, the condensation tube array is docked with the sample cup array, the condensation tube 2.1 stops moving downward, the condensation tube bracket 2.5 continues to move downward, and the spring 2.3 is compressed, so that the sealing ring 2.2 is in a compressed state, ensuring that the sample cup 1.1 and the condensation tube 2.1 are completely sealed;

[0044] 6) The upper rotary arm 3.4 rotates and moves to the top of the waste liquid bottle 3.7, so that the liquid outlet corresponds to the waste liquid bottle 3.7, and the liquid outlets discharge liquid in turn, squeezing out the air in the corresponding pipes;

[0045] 7) The upper rotary arm 3.4 rotates and moves to the top of the condenser 2.1, and the lower slide 4.2 moves to correspond to the docked sample cup 1.1. The lower rotary arm 4.4 remains parallel to the row surface of the sample cup 1.1, and the stirring function is started. Silver sulfate sulfuric acid solution is added to the front and rear rows of condensers 2.1 in turn through the pipeline 1 3.5; during the liquid addition process, the stirring module drives the magnet in the sample cup 1.1 to rotate to realize the stirring function; after all condensers 2.1 are filled with liquid, the upper slide 3.2 returns to the zero position, the lower slide 4.2 returns to the zero position, and the stirring function is turned off.

[0046] 8) The condensing fan 2.6 is started, the heating unit 1.3 is started, the digestion position 1.5 with the sample cup 1.1 is heated to the set temperature, and the temperature is maintained according to the set constant temperature time;

[0047] 9) After the set constant temperature time is up, the heating unit 1.3 stops heating, and the cooling fan 1.4 starts to quickly cool the sample cup 1.1 after heating and digestion until it cools to room temperature;

[0048] 10) The upper rotary arm 3.4 rotates and moves to the top of the condenser tube 2.1, and the lower slide seat 4.2 moves to correspond to the docked sample cup 1.1, and the lower rotary arm 4.4 remains parallel to the row surface of the sample cup 1.1, and the stirring function is started, and ultrapure water is added to the front and rear rows of condensers 2.1 in turn through the second pipe 3.6; after all condensers 2.1 are filled with liquid, the upper slide seat 3.2 returns to the zero position, the lower slide seat 4.2 returns to the zero position, and the stirring function is turned off;

[0049] 11) The lifting mechanism 2.7 is started, the condensation module moves upward, and the condensation tube 2.1 is separated from the sample cup 1.1;

[0050] 12) The lower rotary arm 4.4 rotates and moves to the standard position 1.7, and appropriate amounts of ammonium ferrous sulfate solution, sulfuric acid solution and ultrapure water are added to the front and rear sample cups 1.1 in sequence through pipe seven 6.3, pipe nine 6.5 and pipe ten 6.6;

[0051] 13) The lower rotary arm 4.4 rotates and moves to the digestion position 1.5, and adds appropriate amounts of ferroxine solution to the front and rear sample cups 1.1 in sequence through the pipe 6 6.2;

[0052] 14) The lower rotary arm 4.4 rotates and moves to the standard position 1.7, the stirring module is started, driving the magnet in the sample cup 1.1 to rotate, the color monitoring unit 6.1 is started, facing the side wall of the sample cup 1.1, and potassium dichromate solution is dripped into the sample cup 1.1 at the standard position 1.7 through the pipe 4 4.6. Each time a drop of potassium dichromate solution is dripped, the color monitoring unit 6.1 performs a color judgment until the color of the solution changes to the set color, stops dripping the potassium dichromate solution, records the volume of the potassium dichromate solution consumed, and ends the titration. The stirring module is turned off and the color monitoring unit 6.1 is turned off;

[0053] 15) The lower rotary arm 4.4 rotates and moves to the top of the sample cup in the digestion position 1.5, the stirring module is started, driving the magnet in the sample cup 1.1 to rotate, the color monitoring unit 6.1 is started, facing the side wall of the sample cup 1.1, and the ammonium ferrous sulfate solution is dripped into the sample cup 1.1 through the pipe 6.3. Each time a drop of ammonium ferrous sulfate solution is dripped, the color monitoring unit 6.1 performs a color judgment until the color of the solution changes from yellow to blue-green and finally to reddish brown, the dripping of the ammonium ferrous sulfate solution is stopped, and the volume of the ammonium ferrous sulfate solution consumed by the sample at this position is recorded. The titration of the sample cup 1.1 is completed, and the lower rotary arm 4.4 is moved or rotated to titrate other sample cups 1.1 containing samples in the digestion position 1.5 until all sample cups 1.1 have completed the titration, the stirring module is turned off, the color monitoring unit 6.1 is turned off, and the lower rotary arm 4.4 returns to the zero position;

[0054] 16) The system records and calculates data and outputs the test results.

[0055] The arrangement of the sample cups in the present invention can be in a linear array, a circular array or other array arrangements according to different implementations. The driving structure is adjusted accordingly according to the arrangement. The above-mentioned embodiment is explained using the linear array arrangement as an example. The use of other arrangements of the sample cups cannot be regarded as a limitation of the present invention.

[0056] The fully automatic chemical oxygen demand analyzer based on the dichromate method provided by the present invention replaces the manual detection method with an automated detection process, realizes fully automatic detection of CODCr, ensures the consistency and reliability of detection, eliminates the errors caused by the manual method, and has stable detection conditions, which is convenient for batch detection, greatly reduces labor intensity, and has strong applicability.

[0057] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A fully automatic chemical oxygen demand analyzer based on the dichromate method, characterized in that: include: Digestion module, condensation module, lower liquid adding module, upper liquid adding module, stirring module and titration module; The digestion module comprises two digestion units, one in front and one in the back, each of which comprises a heating panel (1.2), a heating unit (1.3) and a plurality of sample cups (1.1); the upper surface of the heating panel (1.2) is provided with a plurality of marking positions (1.7) and a plurality of digestion positions (1.5); sample cups (1.1) with magnets inside are placed at the marking positions (1.7) and the digestion positions (1.5); an interface is provided at the top of the sample cup (1.1); the sample cups (1.1) of the two digestion units at the digestion positions (1.5) form a sample cup array; the sample cups (1.1) at the digestion positions (1.5) are used to hold samples, and the sample cups (1.1) at the marking positions (1.7) are used to calibrate ammonium ferrous sulfate solution; the heating unit (1.3) is located below the heating panel (1.2); The condensation module comprises two front and rear condensation units, each of which comprises a condensation tube bracket (2.5), a lifting mechanism (2.7) and a plurality of condensation tubes (2.1); the condensation tube bracket (2.5) is arranged above the lifting mechanism (2.7), and a plurality of condensation tubes (2.1) are arranged on the condensation tube bracket (2.5); the lifting mechanism (2.7) drives the condensation tube bracket (2.5) to move up and down, thereby driving a plurality of condensation tubes (2.1) to move up and down; a sealing ring (2.2), a spring (2.3) and a fixing ring (2.4) are arranged on the condensation tube (2.1); the fixing ring (2.4) is fixedly installed on the condensation tube (2.1); the spring (2.3) is sleeved on the condensation tube (2.1) and abuts against the condensation tube bracket (2.5) and the fixing ring (2.4). ), the sealing ring (2.2) is arranged on the spherical joint at the bottom of the condenser (2.1); the condensers (2.1) of the two condensing units constitute a condenser array, the condenser array corresponds to the sample cup array and is arranged directly above the sample cup array, and the spherical joint at the bottom of the condenser (2.1) is adapted to the interface of the sample cup (1.1); when the condenser (2.1) and the sample cup (1.1) are docked, a sealing effect is played; when the condenser module moves downward, the condenser (2.1) and the sample cup (1.1) are docked, the condenser (2.1) stops moving downward, the condenser bracket (2.5) continues to move downward for a distance, the compression spring (2.3) generates pressure, and acts on the sealing ring (2.2) through the fixing ring (2.4) and the condenser (2.1), playing a compression and sealing effect, thereby enhancing the sealing effect; The lower liquid adding module comprises a lower slide rail (4.1), a lower seat (4.2), a lower rotating mechanism (4.3) and a lower rotating arm (4.4); the lower slide seat (4.2) is slidably arranged on the lower slide rail (4.1); the lower rotating arm (4.4) is rotatably arranged on the lower seat (4.2) through the lower rotating mechanism (4.3); and the front end of the lower rotating arm (4.4) is provided with a pipe (4.5) for adding mercuric sulfate solution and a pipe (4.6) for adding high-concentration potassium dichromate solution. Pipeline 4 (4.6) and pipeline 5 (4.7) for adding low-concentration potassium dichromate solution, the lower slide seat (4.2) moves linearly on the lower slide rail (4.1) through the lower driving mechanism, driving the lower rotary arm (4.4) to move linearly, and at the same time the lower rotating mechanism (4.3) is used to drive the lower rotary arm (4.4) to rotate, driving the liquid outlets of pipeline 3 (4.5), pipeline 4 (4.6) and pipeline 5 (4.7) to align with the inlet of the sample cup (1.1); The upper liquid adding module is installed directly above the condensing module and is used to add silver sulfate sulfuric acid solution and ultrapure water to the condensing tube (2.1); The upper liquid adding module comprises an upper slide rail (3.1), an upper slide seat (3.2), an upper rotating mechanism (3.3) and an upper cantilever (3.4); the upper slide seat (3.2) is slidably arranged on the upper slide rail (3.1); the upper rotating arm (3.4) is rotatably arranged on the upper slide seat (3.2) through the upper rotating mechanism (3.3); a pipe 1 (3.5) for adding silver sulfate sulfuric acid solution and a pipe 2 (3.6) for adding ultrapure water are provided at the front end of the upper cantilever (3.4); the upper slide seat (3.2) moves linearly on the upper slide rail (3.1) via the upper driving mechanism, driving the upper cantilever (3.4) to move linearly; at the same time, the upper rotating mechanism (3.3) drives the upper cantilever (3.4) to rotate, driving the liquid outlets of the pipe 1 (3.5) and the pipe 2 (3.6) to align with the inlet of the condenser (2.1); The stirring module comprises two front and rear stirring units, the two stirring units are respectively arranged on the lower sliding seat (4.2), and the stirring module drives the magnet to rotate to perform stirring; The titration module comprises a color monitoring unit (6.1), which is arranged on the lower rotary arm (4.4) and is used to monitor the color change of the liquid in the sample cup (1.1). The front end of the lower rotary arm (4.4) is provided with a pipeline six (6.2) for adding ferrous iron solution, a pipeline seven (6.3) for adding high-concentration ammonium ferrous sulfate solution, a pipeline eight (6.4) for adding low-concentration ammonium ferrous sulfate solution, and a pipeline nine (6.5) for adding sulfuric acid solution. .5) and a pipe ten (6.6) for adding ultrapure water, the lower slide seat (4.2) moves linearly on the lower slide rail (4.1) via a lower driving mechanism, driving the lower rotary arm (4.4) to move linearly, and at the same time the lower rotary mechanism (4.3) drives the lower rotary arm (4.4) to rotate, driving the liquid outlets of pipe six (6.2), pipe seven (6.3), pipe eight (6.4), pipe nine (6.5) and pipe ten (6.6) to align with the inlet of the sample cup (1.1); Each of the digestion units further comprises a cooling fan (1.4), and the cooling fan (1.4) is arranged at a position of the sample cup (1.1) directly opposite to the digestion position (1.5); each of the condensation units further comprises a condensation fan (2.6), and the condensation fan (2.6) is arranged at a position directly opposite to the condensation tube (2.1).

2. The fully automatic chemical oxygen demand analyzer based on the dichromate method according to claim 1, characterized in that: The upper surface of the heating panel (1.2) is also provided with a waste discharge position (1.6), and the waste discharge position (1.6) is provided with a sample cup (1.1) for collecting waste liquid discharged from the liquid outlets of pipeline three (4.5), pipeline four (4.6), pipeline five (4.7), pipeline six (6.2), pipeline seven (6.3), pipeline eight (6.4), pipeline nine (6.5) and pipeline ten (6.6).

3. The fully automatic chemical oxygen demand analyzer based on the dichromate method according to claim 1, characterized in that: The upper liquid adding module also includes a waste liquid bottle (3.7) for collecting waste liquid discharged from the liquid outlets of the pipeline 1 (3.5) and the pipeline 2 (3.6).

4. The fully automatic chemical oxygen demand analyzer based on the dichromate method according to claim 1, characterized in that: The stirring unit comprises a magnet seat (5.2) and a motor (5.3); the motor (5.3) is arranged below the lower slide seat (4.2); the magnet seat (5.2) is arranged above the lower slide seat (4.2); a magnet (5.1) is arranged on the magnet seat (5.2); an output shaft of the motor (5.3) passes through the lower slide seat (4.2) and is drivingly connected to the magnet seat (5.2); the lower slide seat (4.2) moves horizontally, driving the magnet seat (5.2) and the motor (5.3) to move horizontally; at the same time, the motor (5.3) drives the magnet seat (5.2) to rotate, driving the magnet to rotate, thereby stirring.

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