CN1811456B - Fruit and vegetable disinfectant detection method and detection control device - Google Patents

Abstract

The invention discloses a fruit and vegetable disinfectant detection method and a detection control device. It adopts a constant ratio dilution and reduction method. The steps are: dilute the tested high-solution chlorine disinfectant, detect and display the pH value and temperature value of the disinfectant, and set the disinfectant The upper limit and lower limit alarm value of the pH value of the liquid. The detection and control device for implementing the method is composed of a test liquid pipeline system, a dilution water pipeline system, a mixing pipeline system, a liquid replenishment pipeline system and a detection and control system. The invention overcomes the defects of low detection accuracy of disinfectant solution in existing food processing and inability to detect and control the concentration of disinfectant solution on-line. It can accurately detect and control high-concentration chlorine disinfectant on-line and realize intelligent uninterrupted work of the assembly line.

Description

Fruit and vegetable disinfectant detection method and detection control device

technical field

The invention relates to a disinfectant detection method and a detection control device, in particular to a detection method and an intelligent detection control device for detecting high-concentration disinfectant.

Background technique

Food safety is currently a concern of consumers, and fruits and vegetables are widely consumed by consumers, so the safety of this type of food is particularly important. Cleaning and disinfection is an important process in the postharvest processing of fruits and vegetables, especially for the fast-growing fresh-cut fruit and vegetable products, cleaning and disinfection is very important. The quality of the sterilization effect during the cleaning process directly affects the fresh-keeping quality and shelf life of the product, as well as the food safety of consumers. Chlorine disinfectants are currently widely used fungicides in fruit and vegetable processing. Literature research results show that disinfectants containing 100-200 mg/L available chlorine have better disinfection effects on fresh-cut fruits and vegetables. At present, the chlorine detection in the national standard is mostly used in the detection of residual chlorine in the water treatment industry. There are many detection methods for residual chlorine, such as: iodometric method, N, N-diethyl-1,4-phenylenediamine Titration method (DPD method), amperometric titration method and colorimetric method, etc. The iodometric method is a standard method stipulated in the "Hospital Sewage Discharge Standard" (GBJ48-83). This method can only be used to measure water samples with a total residual chlorine content> 1 mg/L, and cannot detect free and combined chlorine; DPD method It is a national standard method, which can measure various residual chlorine components in water samples, and is mainly used in laboratories; amperometric titration can be used to measure various residual chlorine components, and is not interfered by general oxidants, temperature, turbidity, color, etc. in water , the accuracy is also high, but the instrument maintenance operation is required; the colorimetric method is used to determine the total residual chlorine, but when the water sample contains high-valent manganese or NO ₂ >2mg/L, this method cannot be used. Because visual colorimetry is convenient for on-site operation and observation, it is often used in the determination of residual chlorine on site, but the detection accuracy of colorimetry is low. With the improvement of people's living standards, "rest assured to eat, worry-free to use" has become the consensus of people, especially in recent years, fresh-cut vegetable processing has developed rapidly in our country, and food processing enterprises have developed rapidly. In the process, there is a cleaning and disinfection process for raw materials. In order to ensure the sterilization effect and food safety, it is necessary to accurately monitor the cleaning and disinfection process of food processing. However, the current handheld testing equipment can detect the concentration range of 0-10mg/ L, cannot meet the measurement of high-concentration disinfectant. The test paper colorimetric method is often used to detect high-concentration disinfectants, and a range of values is obtained, which not only cannot achieve accurate detection, but also cannot realize online real-time detection and control.

Contents of the invention

The present invention is to overcome the defects of low detection accuracy of disinfectant in the existing food processing and the inability to detect and control the concentration of disinfectant on-line, and provide a method suitable for cleaning and disinfection of food processing raw materials, which can accurately detect and control high A detection method and a detection control device for a concentrated chlorine disinfectant.

Disinfectant detection method of the present invention adopts fixed ratio dilution reduction method, and its steps are:

1. Dilute the tested high-concentration solution chlorine disinfectant

Dilute the high-concentration solution chlorine disinfectant (100-200mg/L) that needs to be measured in proportion to the detection concentration range (0-10mg/L) required by the residual chlorine sensor detector. The specific method is: wash the fruits and vegetables The high-concentration disinfectant to be tested in the tank is quantitatively input into the pipeline system through the metering pump in the detection control device, and at the same time, the tap water for dilution is removed through the activated carbon filter to remove the residual chlorine, and then mixed according to the flow rate required for dilution through the flow meter. pipeline, and fully mixed in the mixing pipeline;

2. Detection shows the concentration value, pH value and temperature value of chlorine disinfectant

The diluted disinfectant is detected by the residual chlorine sensor, pH sensor and temperature sensor installed on the mixing pipeline, and then through the analog-to-digital conversion of the console, the microcomputer restores and displays the concentration value of the detected chlorine disinfectant on the console, and simultaneously displays The pH value and temperature value of the disinfectant;

3. Set the concentration of disinfectant and its pH upper limit and lower limit alarm value.

The numerical value and the upper and lower limit alarm values are displayed on the controller. If the concentration and pH value of the disinfectant solution are lower than the set lower limit, the control system starts the rehydration pump to replenish the disinfectant solution into the disinfection tank.

A detection and control device for implementing a disinfectant detection method is composed of a liquid pipeline system to be tested, a dilution water pipeline system, a mixing pipeline system, a fluid replenishment pipeline system and a detection and control system. Among them, the pipeline system of the liquid to be tested is composed of a suction pipe, a metering pump and an infusion pipe. The lower end of the suction pipe is connected with a filter; Composed of pressure valve, activated carbon filter, flow meter and throttle valve; the flow inlet of the solenoid valve is connected to the inlet of dilution water, and the outlet is connected to the pressure reducing valve, activated carbon filter, flow meter, throttle valve in turn, and the switch of the solenoid valve is connected to the control device; the outlet of the throttle valve in the dilution water pipeline system is connected to the infusion tube connected to the metering pump in the pipeline system of the liquid to be tested through the pipeline, and is connected to the inlet of the serpentine multi-fold mixing pipeline; respectively installed on the mixing pipeline There are temperature sensor, pH sensor and residual chlorine sensor; and the temperature sensor, pH sensor and residual chlorine sensor are respectively connected with the controller, wherein the liquid output port of the residual chlorine sensor is connected with the electromagnetic valve through the pipeline, and the switch of the electromagnetic valve is connected with the controller. Empty the solution in the system; the rehydration pipeline system is composed of a liquid reservoir and a rehydration pump. The liquid inlet of the rehydration pump is connected to the liquid reservoir, and the liquid outlet enters the disinfection cleaning tank through the pipeline. The controller is equipped with a temperature detection instrument, a pH detection instrument, a residual chlorine detection instrument, an alarm and a control electrical switch.

Throttle valve outlet pipeline, metering pump infusion pipeline and mixing pipeline junction are connected by inserting throat. The detection control system is equipped with a detection data storage and printing interface.

The invention overcomes the defects of low detection accuracy of disinfectant solution in existing food processing and inability to detect and control the concentration of disinfectant solution on-line. It can accurately detect and control high-concentration chlorine disinfectant on-line and realize intelligent uninterrupted work of the assembly line. The detection data storage and printing interface provided in the measurement and control device can be connected to a recorder or a computer as required to collect and print detection data in a timely manner. In addition, the entire system adopts a modular structure, and other high-concentration disinfectants can be measured online by replacing the sensor, so as to meet the needs of different fields such as food processing, pharmaceuticals, and sewage treatment.

Description of drawings

Fig. 1 is a schematic diagram of the detection control device of the present invention.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

As shown in Figure 1, a detection control device for implementing a disinfectant detection method is composed of a liquid pipeline system to be tested, a dilution water pipeline system, a mixing pipeline system, a liquid replenishment pipeline system and a detection control system.

Wherein, the pipeline system of the liquid to be tested is composed of a suction pipe 1, a metering pump 2 and an infusion pipe 3, the lower end of the liquid suction pipe 1 is connected with a filter 4; the upper end is connected with a metering pump 2, and the power supply of the metering pump 2 is connected with a controller 5;

The dilution water pipeline system consists of a solenoid valve 6, a pressure reducing valve 7, an activated carbon filter 8, a flow meter 9, and a throttle valve 10; the flow inlet of the solenoid valve 6 is connected to the dilution water inlet, and the outlet is sequentially connected to the pressure reducing valve 7, activated carbon Filter 8, flow meter 9, throttle valve 10, and the switch of solenoid valve 6 is connected to controller 5; the outlet of throttle valve 10 in the dilution water pipeline system is connected to the metering pump 2 in the liquid pipeline system to be tested through the pipeline The infusion tube 3 is converging and connected, and is connected with the inlet of the serpentine multi-fold mixing pipeline 11; so that the disinfectant to be tested and the dilution water enter the mixing pipeline 11 after converging at point a, and the connection at the converging point a adopts an internal insertion throat Tube;

A temperature sensor 12, a pH sensor 13 and a residual chlorine sensor 14 are respectively installed on the mixing pipeline 11; It is connected to the solenoid valve 18 through the pipeline, and the switch of the solenoid valve 18 is connected to the controller 5 for emptying the solution in the system; the liquid replenishment pipeline system is composed of a liquid reservoir 15 and a liquid replenishment pump 16, and the liquid replenishment pump 16 inlet and the reservoir The liquid device 15 is connected, the liquid outlet enters the disinfection cleaning tank 17 through the pipeline, and the power supply of the liquid replenishment pump 16 is connected to the controller 5; the controller 5 is equipped with a temperature detection instrument, a pH detection instrument, a residual chlorine detection instrument, an alarm and a control electrical switch wait. The disinfectant in the disinfectant liquid storage tank 15 is replenished with disinfectant in the cleaning and disinfecting tank 17 by the rehydration pump 16, and the rehydration pump 16 is supplemented with disinfectant according to the set concentration according to the detected concentration of the disinfectant by the controller 5, and the system stops working At this time, the solution in the system is evacuated under the control of the electromagnetic valve 18, and the electromagnetic valve 18 is also controlled by the console 5. The detection control system is equipped with a detection data storage and printing interface, and is connected to a recorder or computer as required to collect and print detection data in a timely manner. In addition, the entire system adopts a modular structure, and other high-concentration disinfectants can be measured online by replacing the sensor, so as to meet the needs of different fields such as food processing, pharmaceuticals, and sewage treatment.

Disinfectant detection method of the present invention adopts fixed ratio dilution reduction method, and its steps are:

1. Dilute the tested high solution chlorine disinfectant

Dilute the high-solution chlorine disinfectant (100-200mg/L) to be measured in proportion to the detection concentration range (0-10mg/L) required by the residual chlorine sensor detector. Its specific method is: the high-concentration disinfectant solution to be tested in the fruit and vegetable cleaning tank 17 is quantitatively input into the pipeline system through the metering pump 2 in the detection control device, and the tap water for dilution is removed through the active carbon filter 8 to remove residual chlorine therein. , enter the mixing pipeline according to the flow rate required for dilution through the flow meter 9, and fully mix in the mixing pipeline 11.

2. The test shows the concentration value, pH value and temperature value of the disinfectant,

The diluted disinfectant is detected by the residual chlorine sensor 14, the pH sensor 13 and the temperature sensor 12 installed on the mixing pipeline 11, and then through the analog-to-digital conversion of the console 5, the detected concentration value is restored and displayed on the console 5 by the microcomputer. On the screen, the pH value and temperature value of the disinfectant are displayed at the same time.

3. Set the concentration of the disinfectant and the pH value upper limit and lower limit alarm value.

Numerical value and upper and lower limit alarm values are displayed on the controller 5. If the concentration of the disinfectant is lower than the set lower limit, the control system starts the replenishment pump 16 to supplement the disinfectant in the disinfection tank 17.

Take the concentration measurement and control of sodium hypochlorite sterilizing and disinfecting solution during cleaning and processing as an example. During work, the concentration of sodium hypochlorite disinfecting solution in the cleaning and sterilizing tank is 100-200mg/L. The used tap water passes through the decompression valve 7 and the active carbon filter 8 to remove residual chlorine in the water, and adjusts the corresponding constant flow through the flow 8 and the throttle valve 9. After mixing with high-concentration sodium hypochlorite at point a and diluting it 10 to 20 times, After entering the mixing pipeline 11, after being further mixed evenly, it is detected by the temperature, pH value and residual chlorine sensors installed in the mixing pipeline 11, and the value is displayed on the controller 5, and the upper and lower limit alarms. When the concentration of sodium hypochlorite disinfectant is lower than the set lower limit, through the feedback signal of the alarm, the controller 5 automatically starts the dosing and replenishment pump, and replenishes the sodium hypochlorite solution in the liquid storage tank 15 into the fruit and vegetable cleaning and sterilizing tank, thereby realizing the assembly line intelligent uninterrupted work.

The invention can be flexibly allocated according to the use requirements of different industries for the detection range of the disinfectant.

Claims (4)

1. a kind of fruit and vegetable disinfectant detection method is characterized in that, adopts constant ratio dilution reduction method, and its steps are: A. Dilute the tested high-concentration chlorine disinfectant Dilute the high-concentration chlorine disinfectant solution with a concentration of 100-200 mg/L to be measured in proportion to the detection concentration range of 0-10 mg/L required by the residual chlorine sensor detector. The specific method is: the fruit and vegetable cleaning tank (17 ) in the high-concentration disinfectant to be tested is quantitatively input into the mixing pipeline (11) in the pipeline system through the metering pump (2) in the detection control device, and at the same time, the tap water for dilution is removed through the activated carbon filter (8). After chlorine, through flow meter (9) by the required flow input mixing line (11) of dilution, and make the two fully mix in mixing line (11); B. The test shows the concentration value, pH value and temperature value of the disinfectant The diluted disinfectant is detected by the residual chlorine sensor (14), pH sensor (13) and temperature sensor (12) installed on the mixing pipeline (11), and then through the analog-to-digital conversion of the console (5), the microcomputer will The detected concentration value reduction is displayed on the console (5), and the pH value and temperature value of the disinfectant are displayed simultaneously; C. Set the concentration of the disinfectant and the upper and lower limit alarm values of the pH value Numerical value and upper and lower limit alarm values are displayed on the console (5), if the concentration of the disinfectant is lower than the set lower limit, the control system starts the replenishment pump (16) to supplement the disinfectant in the disinfection tank (17). 2. A detection and control device implementing the detection method of claim 1, comprising a liquid pipeline system to be tested and a dilution water pipeline system, characterized in that, it also includes a mixing pipeline system, a liquid replenishment pipeline system and a detection and control system, the The pipeline system of the liquid to be tested is composed of a suction pipe (1), a metering pump (2) and an infusion pipe (3). The lower end of the liquid suction pipe (1) is connected with a filter (4), and the upper end is connected with a metering pump (2). , the power supply of the metering pump (2) is connected to the controller (5); The dilution water pipeline system is composed of a first solenoid valve (6), a pressure reducing valve (7), an activated carbon filter (8), a flow meter (9) and a throttle valve (10). The first solenoid valve (6) The flow inlet is connected to the dilution water inlet, and the outlet is connected to the pressure reducing valve (7), activated carbon filter (8), flow meter (9) and throttle valve (10) in turn, and the switch of the first solenoid valve (6) is connected to the control device (5); the outlet of the throttle valve (10) in the dilution water pipeline system is connected through the pipeline with the infusion tube (3) connected to the metering pump (2) in the liquid pipeline system to be tested, and mixed with the serpentine multifold Pipeline (11) inlets are connected; A temperature sensor (12), a pH sensor (13) and a residual chlorine sensor (14) are respectively installed on the mixing pipeline (11); and the temperature sensor (12), the pH sensor (13) and the residual chlorine sensor (14) They are respectively connected to the controller (5), wherein the liquid output port of the residual chlorine sensor (14) is connected to the second solenoid valve (18) through a pipeline, and the switch of the second solenoid valve (18) is connected to the controller (5) for use in the system. The solution is emptied; The liquid replenishment pipeline system is composed of a liquid reservoir (15) and a liquid replenishment pump (16). The liquid inlet of the liquid replenishment pump (16) is connected to the liquid reservoir (15), and the liquid outlet enters the disinfection cleaning tank (17) through the pipeline. , the power supply of the replenishment pump (16) is connected to the controller (5); The controller (5) is equipped with a temperature detection instrument, a pH detection instrument, a residual chlorine detection instrument, an alarm and a control electrical switch. 3. The detection and control device according to claim 2, characterized in that the outlet pipeline of the throttle valve (10) and the infusion tube (3) of the metering pump (2) meet the connection point of the mixing pipeline (11) The place adopts the insertion throat connection. 4. The detection control device according to claim 2, characterized in that, the detection control system is provided with detection data storage and printing interfaces.