CN212964613U

CN212964613U - Device for online COD detection by ultraviolet photometry

Info

Publication number: CN212964613U
Application number: CN202021545396.5U
Authority: CN
Inventors: 金毅; 曹廷睿
Original assignee: Wuxi Chengyong Automation Technology Co ltd
Current assignee: Wuxi Chengyong Automation Technology Co ltd
Priority date: 2020-07-30
Filing date: 2020-07-30
Publication date: 2021-04-13
Anticipated expiration: 2030-07-30

Abstract

The utility model discloses an online COD detection's of ultraviolet photometry device, including LED lamp pearl, the deuterium lamp, first biconvex lens, the second biconvex lens, third biconvex lens, first silicon photodiode, second silicon photodiode, quartzy mobile cuvette, first light filter, second light filter and main body frame, wherein the deuterium lamp, first biconvex lens, first light filter, quartzy mobile cuvette, second biconvex lens and first silicon photodiode set gradually on main body frame's same water flat line, LED lamp pearl, the second light filter, quartzy mobile cuvette, third biconvex lens and second silicon photodiode set gradually on main body frame's another water flat line, absorbance through to different wave bands in the water sample comes to carry out real-time detection to the COD value, because stray light has avoided the influence of stray light to the COD detected value in same light path.

Description

Device for online COD detection by ultraviolet photometry

Technical Field

The utility model relates to a COD detection area, in particular to device that online COD detected of ultraviolet photometry.

Background

COD is one of the most commonly determined items in water quality monitoring and analysis and important indexes for evaluating water body pollution, the current domestic COD determination methods mainly comprise a potassium dichromate method and a potassium permanganate method, and the two methods belong to chemical methods, so that time is consumed, a large amount of reagent cost is consumed, and secondary heavy metal pollution is generated.

Compared with a chemical method, the method for obtaining the COD concentration by utilizing the relation between the absorbance and the COD concentration in the detection has the advantages of simple operation and maintenance, low failure rate, no need of adding a chemical reagent, no secondary pollution, short test time and short response time, and can be applied to on-line monitoring.

The current light path that adopts ultraviolet photometry to detect COD device is single, can not eliminate the influence of turbidity to COD to the light path device is mostly split type, and stray light has very big influence to the COD measured value like this.

SUMMERY OF THE UTILITY MODEL

Utility model purpose: the utility model aims at providing an online COD detection's of ultraviolet photometry device can eliminate turbidity to the influence of COD measured value, adopts the integral type structure to reduce stray light to the influence of COD measured value simultaneously.

The technical scheme is as follows: the utility model relates to an online COD detection device of ultraviolet photometry, including LED lamp pearl, deuterium lamp, first biconvex lens, second biconvex lens, third biconvex lens, first silicon photodiode, second silicon photodiode, quartzy flowing cuvette, first light filter, second light filter and main body frame, LED lamp pearl and first biconvex lens are installed on the left baffle in main body frame in parallel, are located the same height; the deuterium lamp is arranged on the left side of the first biconvex lens, and the center of the light source of the deuterium lamp and the center of the first biconvex lens are positioned on the same horizontal line; the second biconvex lens and the third biconvex lens are nested on a support plate in the main body frame, the center of the second biconvex lens and the center of the first biconvex lens are positioned on the same horizontal line, and the center of the third biconvex lens and the center of the LED lamp bead are positioned on the same horizontal line; a quartz flow cuvette fixed on the main body frame through a gland is arranged between the left baffle and the support plate, a first optical filter and a second optical filter are arranged on the left side of the quartz flow cuvette, the center of the first optical filter and the center of the first biconvex lens are positioned on the same horizontal line, and the center of the second optical filter and the center of the LED lamp bead are positioned on the same horizontal line; the LED lamp is characterized in that a first silicon photodiode and a second silicon photodiode are arranged on the right baffle plate in the main body frame, the center of the first silicon photodiode and the center of the first biconvex lens are located on the same horizontal line, and the center of the second silicon photodiode and the center of the LED lamp bead are located on the same horizontal line.

Preferably, the deuterium lamp is positioned at the focal position on the left side of the first biconvex lens.

Preferably, the first silicon photodiode position coincides with a right focal position of the second biconvex lens, and the second silicon photodiode position coincides with a right focal position of the third biconvex lens.

Preferably, the optical path of the quartz flow cuvette is 10 mm.

Preferably, the main frame is made of black ultraviolet corrosion resistant material.

Has the advantages that: the utility model discloses a holistic light path device has reduced stray light to the influence of COD measured value, has eliminated the influence of turbidity to the COD measured value in the method that utilizes the relation of absorbance and COD concentration to try to get COD concentration simultaneously, can accurately obtain the COD measured value in real time.

Drawings

Fig. 1 is a top view of the present invention;

fig. 2 is a left side view of the present invention.

Detailed Description

As shown in fig. 1-2, for the utility model discloses a structure diagram, the utility model discloses a LED lamp pearl 1, deuterium lamp 2, first biconvex lens 3, second biconvex lens 4, third biconvex lens 5, first silicon photodiode 6, second silicon photodiode 7, quartzy mobile cuvette 8, first light filter 9, second light filter 10 and main body frame, 550nmLED lamp pearl has been adopted wherein, 254 mm's the first silicon photodiode of silicon light, 550 mm's the second silicon photodiode of silicon light, 254 nm's first filter and 550 nm's second filter to whole utility model's main body frame material has adopted the material that black resists ultraviolet corrosion.

In the utility model, the LED lamp bead 1 and the first biconvex lens 3 are arranged on the left baffle 11 in the main body frame in parallel and are positioned at the same height; the deuterium lamp 2 is arranged at the focal position at the left side of the first biconvex lens 3, and the center of the light source of the deuterium lamp 2 and the center of the first biconvex lens 3 are positioned on the same horizontal line; the second biconvex lens 4 and the third biconvex lens 5 are nested on a support plate 12 in the main body frame, the center of the second biconvex lens 4 and the center of the first biconvex lens 3 are positioned on the same horizontal line, and the center of the third biconvex lens 5 and the center of the LED lamp bead 1 are positioned on the same horizontal line; a quartz flow cuvette 8 fixed on the main body frame through a gland 13 is arranged between the left baffle plate 11 and the support plate 12, the optical path of the quartz flow cuvette 8 is 10mm, a first optical filter 9 and a second optical filter 10 are arranged on the left side of the quartz flow cuvette 8, the center of the first optical filter 9 and the center of the first biconvex lens 3 are positioned on the same horizontal line, and the center of the second optical filter 10 and the center of the LED lamp bead 1 are positioned on the same horizontal line; the main body frame is provided with a first silicon photodiode 6 and a second silicon photodiode 7 on a right baffle plate 14, the center of the first silicon photodiode 6 and the center of the first biconvex lens 3 are positioned on the same horizontal line, the positions of the first silicon photodiode and the right focal position of the second biconvex lens 4 are consistent, the center of the second silicon photodiode 7 and the center of the LED lamp bead 1 are positioned on the same horizontal line, and the positions of the second silicon photodiode and the right focal position of the third biconvex lens 5 are consistent.

The utility model discloses at the during operation, deuterium lamp 2 lights, launch in succession and stable 190 nm-400 nm's light, light reachs 254 nm's first light filter 9 after 3 spotlight of first biconvex lens, 254 nm's first light filter 9 will be removed except that the light filtering of 254nm, during pure 254nm light is penetrated quartzy flowing cell 8, some light can be influenced by aquatic COD and turbidity, another part light shines in 254 nm's first silicon photodiode 6 after the 4 focuses on of second biconvex lens, obtain the absorbance value Y of 254nm wavelength in the water sample₂₅₄。

When the novel middle 550nm LED lamp bead 1 is lighted, continuous light with the peak value of 550nm is emitted, the light passes through the 550nm second optical filter 10, the 550nm second optical filter 10 filters out light except 550nm,the pure 550nm light is emitted into a quartz flowing cuvette 8, one part of light is influenced by turbidity, and the other part of light is irradiated into a 550nm second silicon photodiode 7 after being focused by a third biconvex lens 5 to obtain an absorbance value Y of the 550nm wavelength in the water sample₅₅₀。

In an ultraviolet photometry, COD standard solutions with different concentrations are taken to detect the absorbance AD value at the wavelength of 254 nm; taking turbidity standard solutions with different concentrations to detect absorbance AD values at the wavelength of 550nm, and establishing a standard curve through the standard solutions with different concentrations:

COD concentration versus absorbance standard curve: y is_COD＝AX₁+ C1 type one

Absorbance versus turbidity at 254 nm: y is₂₅₄＝BX₂+C2

546nm absorbance vs turbidity curve: y is₅₅₀＝CX₃+C3

Wherein A, B, C, C1, C2, and C3 are all constants.

According to the superposition of the Lambert-beer law, the absorbance of the solution at a wavelength of 254nm is:

A_{total COD (254)}＝A_{Turbidity (254)}+A_COD(254)

The absorbance A at 254nm was detected in the same solution_COD(254)Turbidity A at 550nm_{Turbidity (550)}Can be according to Y₅₅₀＝CX₃+ C3 result in, let A_{Total COD (254)}Is M, A_COD(254)Is M1, A_{Turbidity (254)}Is M2, A_{Turbidity (550)}M3, COD concentration Y, turbidity concentration Y₂And then:

Y₂＝CM3+C3；

Y₂＝BM2+C2；

then M2 ═ (CM3+ C3-C2)/B,

since M1 is M-M2, M1 is M- (CM3+ C3-C2)/B, and when it is substituted into formula one, the COD concentration value is:

y ═ a { M- (CM3+ C3-C2)/B } + C1 formula two

Formula two is promptly the utility model discloses well ultraviolet absorption method measures COD's standard curve equation, the utility model discloses an 254nm in the measurement water sample and 550 nm's absorbance value come the substitution formula in, get rid of the measurement and calculation of the COD value under the turbidity influence.

Claims

1. The utility model provides a device that online COD detected of ultraviolet photometry which characterized in that: the LED lamp comprises an LED lamp bead (1), a deuterium lamp (2), a first biconvex lens (3), a second biconvex lens (4), a third biconvex lens (5), a first silicon photodiode (6), a second silicon photodiode (7), a quartz flow cuvette (8), a first optical filter (9), a second optical filter (10) and a main body frame, wherein the LED lamp bead (1) and the first biconvex lens (3) are arranged on a left baffle (11) in the main body frame in parallel and are positioned at the same height; the deuterium lamp (2) is arranged on the left side of the first biconvex lens (3), and the center of the light source of the deuterium lamp (2) and the center of the first biconvex lens (3) are positioned on the same horizontal line; the second biconvex lens (4) and the third biconvex lens (5) are nested on a support plate (12) in the main body frame, the center of the second biconvex lens (4) and the center of the first biconvex lens (3) are positioned on the same horizontal line, and the center of the third biconvex lens (5) and the center of the LED lamp bead (1) are positioned on the same horizontal line; a quartz flow cuvette (8) fixed on the main body frame through a pressing cover (13) is arranged between the left baffle plate (11) and the supporting plate (12), a first optical filter (9) and a second optical filter (10) are arranged on the left side of the quartz flow cuvette (8), the center of the first optical filter (9) and the center of the first biconvex lens (3) are located on the same horizontal line, and the center of the second optical filter (10) and the center of the LED lamp bead (1) are located on the same horizontal line; the LED lamp is characterized in that a first silicon photodiode (6) and a second silicon photodiode (7) are arranged on a right baffle (14) in the main body frame, the center of the first silicon photodiode (6) and the center of the first biconvex lens (3) are located on the same horizontal line, and the center of the second silicon photodiode (7) and the center of the LED lamp bead (1) are located on the same horizontal line.

2. The on-line COD detection device by uv photometry according to claim 1, wherein: the deuterium lamp (2) is positioned at the focal position at the left side of the first biconvex lens (3).

3. The on-line COD detection device by uv photometry according to claim 1, wherein: the position of the first silicon photodiode (6) is consistent with the position of the right focus of the second biconvex lens (4), and the position of the second silicon photodiode (7) is consistent with the position of the right focus of the third biconvex lens (5).

4. The on-line COD detection device by uv photometry according to claim 1, wherein: the optical path of the quartz flow cuvette (8) is 10 mm.

5. The on-line COD detection device by uv photometry according to claim 1, wherein: the main body frame is made of black ultraviolet corrosion resistant material.