Most of the common heavy metal zinc in surface water comes from industrial wastewater from mining, smelting, galvanizing and other industries. Generally, low content of zinc ions is less toxic. When zinc ions are enriched in soil or water, it will cause biological damage. harm. At present, there are many kinds of detection instruments for heavy metal zinc in water, such as laboratory desktop, portable and real-time online monitoring.
But no matter which instrument you choose, you must first know the instrument-related performance and technical requirements of heavy metal zinc. With this information, you can choose the equipment that suits you more quickly.
The technical requirements of general heavy metal zinc automatic online monitoring instrument are mainly divided into three aspects: basic requirements of equipment, performance requirements, and safety requirements.
Technical requirements for automatic online monitoring instrument for heavy metal zinc
Basic requirements of the instrument
1. The display of the instrument should be free of stains and damage. All display interfaces should be in Chinese, and the characters should be uniform and clear, and the screen should be free of vignetting, black spots, rainbows, bubbles, flickering and other phenomena. The display screen can prompt the whole program operation, which is convenient for users to quickly familiarize themselves with the instrument operation process.2. The casing of the instrument should be made of corrosion-resistant materials, and the surface should be free of cracks, deformation, dirt, burrs, etc. The surface coating should be uniform, free of corrosion, rust, peeling and wear.
3. The assembly of product parts inside the instrument should be firm, the parts should not be loose, and the buttons, switches, door locks and other components should be flexible and reliable. The main components should have corresponding signs and text descriptions. The analysis flow diagram should be marked at the conspicuous position of the instrument.
4. The enclosure of the instrument should meet the requirements of the IP 52 protection class specified in GB 4208.
Instrument performance requirements
1. The sampling/measurement unit should be made of materials with poor anti-corrosion and adsorption properties, which will not affect the measurement results due to the corrosion and adsorption of reagents or samples. The measurement part should ensure the accuracy of injection of water samples, standard solutions, reagents, etc.2. The digestion unit should adopt high temperature, high pressure, ultraviolet and other digestion methods, which can convert all zinc and its compounds in the water sample into zinc ions. Corrosion and high temperature resistant materials should be used and easy to clean. It should have automatic heating device and temperature sensor, which can set digestion time and temperature. There should be cooling devices and safety guards to maintain constant temperature and pressure.
3. The reaction module of the analysis unit should be constructed of anti-corrosion materials and easy to clean. The output signal of the detection module should be stable.
4. The control unit should have a feedback function for abnormal information recording (over-range alarm, lack of reagent alarm, component failure alarm and over-standard alarm, etc.), and should use sound and photoelectric methods to alarm. Manual and automatic cleaning functions are required for injection/metering, digestion and analysis units. In the process of use, if an unexpected power failure occurs and the power is turned on again, the instrument can automatically discharge the substances and reagents to be tested that were being measured before the power failure, automatically clean each channel and reset to the state of restarting the test. If it is in the heating and digestion state before power off, it can automatically cool down after power on again, and reset to the state of restarting the test. The data processing system shall have the functions of data and operation log collection, storage, processing, display and output, shall be able to store at least 12 months of original data and operation logs, and can set conditions to query and display historical data. The unit of instrument data is mg/L, with at least two significant figures after the decimal point. There should be automatic standard verification and automatic calibration, and the results should be recorded in the run log. It should have the function of automatic switching between high and low ranges, and the range switching will not affect the normal display of monitoring data and the normal output of signals. It should have a digital communication interface, output relevant data and operation logs through the digital communication interface, and can receive external remote control commands.
Instrument Safety Requirements
1. The external structure of the instrument should comply with the relevant regulations of GB4793.1, and the insulation resistance between the power lead-in and the casing should not be less than 20MΩ.2. The instrument can withstand 50 Hz, 1.5 kV AC RMS continuous voltage test for 1 min between the power inlet and the casing, with a current limit of 5 mA, without arcing and breakdown.
3. The leakage current of the instrument is not more than 5 mA.
4. There should be a leakage protection device and an overload protection device to prevent personal electric shock and accidental burnout of the instrument.
5. The labeling of the instrument shall comply with the relevant provisions of GB4793.1, and the dangerous parts such as high temperature, high pressure, corrosion, poisonous and harmful shall have warning labels.
6. Should have a good grounding port.
The above are the technical requirements of the heavy metal zinc automatic online monitor. You can refer to these conditions when producing and selecting.
