The performance comparison of heavy metal lead cadmium detectors can be carried out from the dimensions of detection technology, sensitivity, detection range, stability, ease of operation, and application scenarios. Equipment with different technical routes have their own emphasis on performance. The following is a specific analysis:
1、 Equipment based on electrochemical stripping voltammetry
Performance Characteristics
High sensitivity: By applying a reduction potential to precipitate metal ions on the surface of the working electrode, and then increasing the potential to oxidize and dissolve them, the metal species can be identified and the concentration can be calculated based on a specific dissolution potential, enabling trace detection. For example, the cadmium detection limit of the portable heavy metal detection device using the Leinde voltammetry method is ≤ 0.10mg/kg, while the cadmium detection range of the KemioHM heavy metal detector is 0.2-10 μ g/L, with a resolution of 0.1 μ g/L.
Quick response: Single heavy metal detection takes only 30 seconds, and simultaneous detection of multiple heavy metals takes no more than 5 minutes. The KemioHM heavy metal detector has a detection time of 3 minutes and can automatically determine whether the indicators are qualified.
Strong anti-interference ability: equipped with a micro electrochemical mixer, significantly improving detection sensitivity; Adopting automatic temperature compensation technology, it is not affected by sample turbidity, chromaticity, particulate matter, and stray light interference.
Strong portability: Supports dual power supply (external 220V AC power supply+built-in lithium battery), can work continuously for more than 8 hours without external power supply; The weight of the host is ≤ 3kg, equipped with a portable carrying case, built-in large capacity battery, supports AC/DC power supply and car power supply.
Applicable scenarios
On site rapid detection: suitable for environmental emergency monitoring, food safety sampling, real-time monitoring of industrial wastewater discharge outlets, and other scenarios.
Mobile detection requirements: The portable design of the equipment can adapt to mobile scenarios such as fields, grain depots, and markets.
Representative product
The portable heavy metal detection device using the L é end voltammetry method can provide results for single elements in as fast as 30 seconds, and for simultaneous detection of multiple elements in ≤ 5 minutes. The detection limit (Cd) is ≤ 0.10mg/kg.
KemioHM heavy metal detector: using printed sensor technology, based on the principle of anodic stripping voltammetry, with a detection time of 3 minutes, automatic temperature compensation, and automatic data storage.
2、 Equipment based on optoelectronic technology
Performance Characteristics
High precision: Quantitative analysis of heavy metal content in samples through optoelectronic technology to ensure data accuracy. For example, the detection limit of lead, cadmium and other elements in the rapid determination instrument for heavy metals in edible mushrooms of rice, grains and aquatic products is as low as 20ppb (0.02mg/kg), which meets food safety standards (such as cadmium limit ≤ 0.2mg/kg).
Good stability: using pulse constant current driving technology to avoid light attenuation and temperature drift, with a linear error of ± 1.0% and an absorbance accuracy of ± 2.0%.
Multi element synchronous detection: supports the detection of harmful elements such as lead, cadmium, chromium, mercury, arsenic, as well as customized items such as iron, nickel, aluminum, etc. Some equipment can be extended to 8 elements to complete multiple heavy metal detection at once.
Efficient data processing: Equipped with high-performance processors and large storage space, it can store a large amount of detection data; Supports WIFI/USB data transmission, with a built-in thermal printer that can print test results in real-time.
Applicable scenarios
Food safety testing: applicable to heavy metal testing in the processes of grain storage, processing, circulation, and supervision.
Environmental monitoring: can be used for quantitative analysis of heavy metal elements in media such as water quality and soil.
Representative product
Rice, cereal and aquatic products edible mushroom heavy metal rapid analyzer: single sample detection time ≤ 15 minutes, dual channel simultaneous detection of two samples ≤ 20 minutes (including pre-treatment), built-in 12 independent detection channels can process multiple samples in parallel.
3、 Equipment based on X-ray fluorescence (XRF) technology
Performance Characteristics
Non destructive testing: No pre-treatment of the sample is required, and solid and liquid samples can be directly tested.
Quick detection: On site testing of machine models requires ≤ 5 minutes per sample to meet the needs of large-scale surveys.
High sensitivity: The detection limit of mainstream portable XRF detectors for cadmium can reach 0.05 μ g/kg, meeting the precise screening needs of agricultural land.
Multi element detection: covering at least 5 key heavy metals (cadmium, mercury, arsenic, lead, chromium) specified in GB15618, and high-end models can be extended to 16 elements such as copper, zinc, nickel, etc.
Applicable scenarios
Soil pollution detection: suitable for heavy metal detection in scenarios such as safe use of agricultural land and remediation of industrial contaminated sites.
Large scale census: With the trend of miniaturization and integration of equipment, it can be integrated into drones and soil samplers to achieve the linkage of "aerial scanning+ground fixed-point detection".
Representative product
Professional level soil heavy metal detector: The detection limit for cadmium can reach 0.05 μ g/kg, supporting "direct measurement of moist soil samples" (moisture content ≤ 30%) without drying.