Cloth dyeing wastewater quality detection system and method

Abstract

The invention is applicable to the field of water quality detection systems, and provides a cloth dyeing wastewater quality detection system and method. The heating module is used for heating the mixed solution in the sampler from a normal temperature to a preset temperature in a discontinuous heating manner so as to reduce the air permeability of an oil film in the sample; the heating timing module is used for recording the interval time and the heating time of the heating work of the heating module and sending a feedback signal to the control module after the time reaches a preset threshold value; the control module receives the feedback signal and controls the heating module to start and stop working; and the dissolved oxygen concentration detection module is used for detecting the content of dissolved oxygen in the sampler, so that the influence caused by a small amount of vegetable fat in a detection solution can be reduced, the precision of detecting the biochemical oxygen demand (BOD5) in the bast fiber textile wastewater is improved, the error rate of an experimental result is reduced, and the accuracy of a numerical value is ensured.

Description

Technical Field

[0001] The present invention relates to the field of water quality detection systems, and in particular to a cloth dyeing wastewater water quality detection system and method. Background Art

[0002] The dyeing wastewater treatment process is a complex process, mainly including pretreatment, biological treatment, chemical treatment and deep treatment. The specific treatment process includes: 1. Pretreatment: This step is mainly used to remove suspended matter, sediment and large particles in the wastewater. 2. Biological treatment: This is the key link in the treatment of dyeing wastewater, which degrades organic matter in the wastewater by utilizing the metabolic capacity of microorganisms. 3. Chemical treatment: Chemical treatment methods include chemical flocculation, chemical oxidation, adsorption and electrochemical methods. 4. Deep treatment: Further remove residual pollutants in the wastewater and improve water quality.

[0003] Among them, wool textile wastewater treatment and hemp textile wastewater treatment have subtle differences based on the above treatment steps. Furthermore, for the subsequent wastewater detection steps, hemp textile wastewater detection also has some special indicators to monitor compared with ordinary wastewater detection, such as biochemical oxygen demand (BOD5): BOD5 reflects the content of biodegradable organic matter in water, which is determined by measuring the consumption of organic matter by microorganisms within a certain period of time.

[0004] At present, the detection steps of biochemical oxygen demand (BOD5) mainly adopt the five-day culture method, which is to fill the sample solution into a completely sealed dissolved oxygen bottle, culture it in the dark at (20±1)℃ for 5 days, and measure the mass concentration of dissolved oxygen in the water sample before and after culture to obtain the oxygen consumption, which can be measured by iodine titration or electrochemical probe method. It mainly uses the oxygen content consumed by degrading organisms (microorganisms) in the process of degrading biodegradable organic matter to indirectly reflect the content of biodegradable organic matter.

[0005] However, some hemp textile wastewater contains a small amount of vegetable oil (for example, in the extraction and preparation of ramie fiber, vegetable oil is used to oil the fiber to increase the softness and gloss of the fiber, and it also helps the smooth spinning process). These oil contents are small and are rarely used as the main detection indicators. However, the permeability of the oil film affects the flow of gases (such as conversion gases volatilized during the microbial degradation process, such as CO2). The accumulation of conversion gas content in the liquid will reduce the degradation rate of the degrading organisms, thereby causing detection errors.

[0006] In summary, the prior art obviously has inconveniences and defects in practical use, so it is necessary to improve it. Summary of the invention

[0007] In view of the above-mentioned defects, the object of the present invention is to provide a cloth dyeing wastewater quality detection system, which can reduce the impact of a small amount of vegetable oil in the detection solution, improve the accuracy of detecting the biochemical oxygen demand (BOD5) in hemp textile wastewater, reduce the error rate of the experimental results, and ensure the accuracy of the numerical values.

[0008] In order to achieve the above-mentioned purpose, the present invention provides a water quality detection system for cloth dyeing wastewater, comprising a sampler; a heating module, which uses intermittent heating to heat the mixed solution in the sampler from a normal temperature to a predetermined temperature to reduce the air permeability of the oil film in the sample; wherein the normal temperature is the lowest temperature in the sampler when the heating module is not working; a heating timing module, which is used to record the interval time and heating time of the heating work of the heating module, and send a feedback signal to the control module after the time reaches a predetermined threshold; a control module, which receives the feedback signal and controls the start and stop of the heating module; and a dissolved oxygen concentration detection module, which detects the dissolved oxygen content in the sampler.

[0009] According to the cloth dyeing wastewater quality detection system of the present invention, the normal temperature is 15-25°C.

[0010] The cloth dyeing wastewater water quality detection system according to the present invention further comprises a conversion gas concentration detection module, which is used to detect the concentration of conversion gas volatilized during the degradation process of biodegradable organic matter.

[0011] According to the cloth dyeing wastewater water quality detection system of the present invention, the heating temperature of the heating module is T2=T1+(ΔT×z); wherein T1 refers to the normal temperature, ΔT is the preset growth temperature, and z is the number of operation times of the heating module; when the value detected by the conversion gas concentration detection module increases at a constant value, the z value is constant, otherwise, the z value is increased by one.

[0012] According to the cloth dyeing wastewater quality detection system of the present invention, the heating module stops heating immediately after heating the sample temperature in the sampler from the normal temperature to the predetermined temperature.

[0013] According to the cloth dyeing wastewater quality detection system of the present invention, the interval time is an interval time of a fixed value.

[0014] According to the cloth dyeing wastewater water quality detection system of the present invention, the interval time is determined by the dissolved oxygen concentration value R detected in real time by the dissolved oxygen concentration detection module; the control module has a reference dissolved oxygen concentration comparison value R0; when R1<R0 / n, the control module controls the heating module to start, and R1 is the actual dissolved oxygen concentration value detected by the instrument.

[0015] According to the cloth dyeing wastewater water quality detection system of the present invention, the control module calculates the final oxygen consumption after the degradation of biodegradable organic matter as R0-R1, and the BOD5 content is: B=(R0-R1)×Bi; wherein R1 is the actual dissolved oxygen concentration value detected by the dissolved oxygen concentration detection module after the experiment is completed, and Bi is the unit conversion coefficient.

[0016] The method for detecting the water quality of cloth dyeing wastewater according to the present invention comprises: step S1, sampling textile wastewater and placing it in a sampler, and placing the sampler in a heating module; step S2, adding a dissolved oxygen solution of a predetermined volume and a predetermined oxygen content to the sampler; step S3, pouring the dissolved oxygen solution of the same volume and oxygen content as step S2 into another sampler to prepare a reference group, and placing it in the same heating module; step S4, starting the test, and the heating module uses intermittent heating to heat the solution temperature in the sampler from a normal temperature to a predetermined temperature; in step S4, the detection value in the control group at the same time is the dissolved oxygen concentration comparison parameter R0, and is uploaded to the control module.

[0017] The present invention provides a water quality detection system for cloth dyeing wastewater, comprising a sampler; a heating module, which uses intermittent heating to heat the mixed solution in the sampler from the normal temperature to a predetermined temperature to reduce the air permeability of the oil film in the sample; wherein the normal temperature is the lowest temperature in the sampler when the heating module is not working; a heating timing module, which is used to record the interval time and heating time of the heating module heating work, and send a feedback signal to the control module after the time reaches a predetermined threshold; a control module, which receives the feedback signal and controls the start and stop of the heating module; and a dissolved oxygen concentration detection module, which detects the dissolved oxygen content in the sampler. The present invention can reduce the impact of a small amount of vegetable oil in the detection solution, improve the accuracy of detecting the biochemical oxygen demand (BOD5) in hemp textile wastewater, reduce the error rate of the experimental results, and ensure the accuracy of the numerical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the consumption of oxygen content in the solution of the present invention.

[0019] Figure 2 This is a comparison chart of gas flow before and after heating; DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0021] See also Figure 1The present invention provides a system and method for detecting the water quality of fabric dyeing wastewater. The system comprises a sampler for containing a mixed solution of wastewater solution and dissolved oxygen. The material used in the sampler has a certain thermal conductivity to facilitate the transfer of external heat (a glass jar can be used); The heating module uses intermittent heating to heat the temperature of the mixed solution (wastewater solution, dissolved oxygen) in the sampler from the normal temperature to a predetermined temperature (a thermometer is set in the sampler) to reduce the permeability of the oil film in the solution; wherein the normal temperature is the lowest temperature in the sampler when the heating module is not working. In the present embodiment, the normal temperature is 15-25°C, specifically 20±1°C. At this temperature, the activity of the degrading organisms is the highest, and efficient degradation of biodegradable organic matter is achieved; wherein the heating module is preferably heated by a water bath, and includes a heating cavity filled with water and a heating unit (the heating unit includes a heating tube, a heating controller, etc., which are all commonly used heating components). This heating method (water bath heating) can achieve uniform heating of the solution, on the one hand avoiding concentrated heating (local temperature is too high) resulting in uneven activity of the degrading organisms, and on the other hand avoiding concentrated heating (local temperature is too high) resulting in uneven volatilization of dissolved oxygen.

[0022] A heating timing module, which is used to record the interval time and heating time of the heating module's heating work, and send a feedback signal to the control module when the time reaches a predetermined threshold; The control module receives the feedback signal and controls the start and stop of the heating module.

[0023] The dissolved oxygen concentration detection module detects the dissolved oxygen content in the sampler. It can measure the oxygen content in the mixed solution during the degradation reaction in real time. The dissolved oxygen concentration detection module generally uses an inserted oxygen content detector.

[0024] In the first embodiment, the heating temperature T2 (the heating temperature refers to the maximum temperature at which the heating module heats the solution after operation) and the interval time of the heating module are both preset fixed values; normally, the heating temperature T2 should not exceed 60±2°C. Considering the oxygen consumption in the dissolved oxygen, the heating temperature T2 can be taken at 50~55°C, and the interval time is half a day (i.e., 6 hours).

[0025] The specific operation is that the control module controls the heating module to heat the solution in the sampler from the normal temperature to the heating temperature T2 every half a day (ie 6 hours), and then stops heating.

[0026] In the second embodiment, the detection system provided by the present application also includes a conversion gas concentration detection module, which is used to detect the concentration of conversion gas volatilized by biodegradable organic matter during the degradation process (for example, the volatilized CO2 can be detected, and the conversion gas concentration detection module can use a CO2 concentration detector, and of course, other gases converted by microorganisms can also be detected). In this embodiment, the heating temperature T2 of the heating module is affected by the detection result of the conversion gas concentration detection module.

[0027] Specifically, the heating temperature of the heating module is T2=T1+(ΔT×z); wherein T1 refers to the normal temperature, ΔT is the preset growth temperature (usually 2~5°C), and z is the number of operation of the heating module (0, 1, 2...); when the value detected by the conversion gas concentration detection module increases at a constant value (compared with the value detected by the conversion gas concentration detection module in the last heating interval, the increase in the value detected by the conversion gas concentration detection module in the two heating intervals is constant), the z value is constant, otherwise, the z value is increased by one. The heating module using the above formula adopts a "groping" temperature rise mode, which can self-adjust the appropriate heating temperature. It is further indicated that this "groping" temperature rise mode can also match the heating temperature with the best air permeability for different vegetable oil contents (i.e. different coverage and oil film thickness); at the same time, it can also exclude the situation where there is no vegetable oil in the wastewater, that is, if there is no vegetable oil, the concentration increase detected by the conversion gas concentration detection module under a single interval time is equal (z value is 0), and the heating temperature T2 is equal to the normal temperature T1, so as to ensure the optimal activity of the degradation organisms. If there is vegetable oil in the wastewater, the heating temperature T2 will rise steadily until the concentration detected by the conversion gas concentration detection module at a single interval time rises to a constant value (at this temperature, the permeability of the vegetable oil in the wastewater is optimal, and the conversion gas produced by the biodegradable organic matter during the degradation process can be almost separated from the liquid, Figure 2 as shown).

[0028] See also Figure 1 In the figure, curve 1 is the oxygen consumption of the mixed liquid without oil and fat cultured in the dark at (20±1)℃ for 5 days, and curve 2 is the oxygen consumption curve in the above embodiment, wherein the X1 interval indicates that the degradation rate of the microorganisms is reduced due to the inhibition of the conversion gas, and the X2 interval indicates that the degradation rate of the microorganisms is restored (oxygen consumption increases) after the conversion gas is released, and the temperature rises and a small amount of oxygen in the dissolved oxygen volatilizes.

[0029] After the heating module heats the solution temperature in the sampler from the normal temperature to the predetermined temperature, the heating is stopped immediately, and then the temperature is naturally lowered. During the cooling process, the sampler can be separated from the heating module to achieve rapid cooling, and the microorganisms can enter the optimal activity state after cooling. Since the gas evaporates quickly, after heating to the heating temperature T2, the converted gas can evaporate quickly from the liquid, and then after a predetermined time interval, the next discharge is carried out.

[0030] At the same time, the interval time is determined by the dissolved oxygen concentration value R detected in real time by the dissolved oxygen concentration detection module; the control module has a reference dissolved oxygen concentration comparison value R0 (the reference dissolved oxygen concentration comparison value R0 will be described in detail below); when R1<R0 / n, the control module controls the heating module to start, and R1 is the actual dissolved oxygen concentration value detected by the instrument.

[0031] Based on the above-mentioned embodiment 2, the present application also provides a method for detecting water quality of cloth dyeing wastewater, the method comprising: Step S1, sampling textile wastewater and placing it in a sampler 1, and placing the sampler 1 in a heating module (ie, a heating chamber containing water).

[0032] Step S2, adding a dissolved oxygen solution of a predetermined volume and a predetermined oxygen content into the sampler 1; Step S3, pouring the dissolved oxygen solution of the same volume and oxygen content as in step S2 into another sampler 1 to prepare a reference group (the reference group is also equipped with a dissolved oxygen concentration detection module and placed in the same heating module); Step S4, starting the test, the heating module is started and the temperature of the solution in the sampler is heated from the normal temperature to the predetermined temperature by intermittent heating.

[0033] In step S4, the detection value in the control group at the same time is the control dissolved oxygen concentration comparison value R0, and is uploaded to the control module.

[0034] The control module calculates the final oxygen consumption after degradation of biodegradable organic matter as R0-R1, and the content of BOD5 is: B=(R0-R1)×Bi; where R1 is the actual dissolved oxygen concentration value detected by the dissolved oxygen concentration detection module after the experiment is completed, and Bi is the unit conversion coefficient.

[0035] The total duration of the above experiment is 5 days.

[0036] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A cloth dyeing wastewater quality detection system, characterized in that: Includes sampler; A heating module, which heats the mixed solution in the sampler from a normal temperature to a predetermined temperature by intermittent heating to reduce the air permeability of the oil film in the sample; wherein the normal temperature is the lowest temperature in the sampler when the heating module is not working; A heating timing module, which is used to record the interval time and heating time of the heating module's heating work, and send a feedback signal to the control module when the time reaches a predetermined threshold; A control module receives feedback signals and controls the start and stop of the heating module; The dissolved oxygen concentration detection module detects the dissolved oxygen content in the sampler.

2. The cloth dyeing wastewater quality detection system according to claim 1, characterized in that: The normal temperature is 15-25°C.

3. The cloth dyeing wastewater quality detection system according to claim 1 or 2, characterized in that: It also includes a conversion gas concentration detection module, which is used to detect the concentration of conversion gas volatilized during the degradation process of biodegradable organic matter.

4. The cloth dyeing wastewater quality detection system according to claim 3, characterized in that: The heating temperature of the heating module is T2 = T1 + (ΔT × z); wherein T1 refers to the normal temperature, ΔT is the preset increase temperature, and z is the number of times the heating module is operated; When the value detected by the conversion gas concentration detection module increases at a constant value, the value z remains constant; otherwise, the value z increases by one.

5. The cloth dyeing wastewater quality detection system according to claim 4, characterized in that: The heating module stops heating immediately after heating the sample in the sampler from a normal temperature to a predetermined temperature.

6. The cloth dyeing wastewater quality detection system according to claim 1 or 2, characterized in that: The interval time is a fixed value interval time.

7. The cloth dyeing wastewater quality detection system according to claim 2 or 4, characterized in that: The interval time is determined by the dissolved oxygen concentration value R detected in real time by the dissolved oxygen concentration detection module; The control module has a comparison value R0 of the dissolved oxygen concentration; When R1<R0 / n, the control module controls the heating module to start, and R1 is the actual dissolved oxygen concentration value detected by the instrument.

8. The cloth dyeing wastewater quality detection system according to claim 7, characterized in that: The control module calculates the final oxygen consumption after degradation of biodegradable organic matter as R0-R1, and the content of BOD5 is: B=(R0-R1)×Bi; where R1 is the actual dissolved oxygen concentration value detected by the dissolved oxygen concentration detection module after the experiment, and Bi is the unit conversion coefficient.

9. A detection method using the cloth dyeing wastewater quality detection system according to claim 8, characterized in that: include: Step S1, sampling textile wastewater and placing it in a sampler, and placing the sampler in a heating module; Step S2, adding a dissolved oxygen solution of a predetermined volume and a predetermined oxygen content into the sampler; Step S3, pouring the dissolved oxygen solution of the same volume and oxygen content as in step S2 into another sampler to prepare a reference group, and placing it in the same heating module; Step S4, starting the test, the heating module uses intermittent heating to heat the solution temperature in the sampler from the normal temperature to the predetermined temperature; In step S4, the detection value in the control group at the same time is the dissolved oxygen concentration comparison parameter R0, and is uploaded to the control module.

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