Application of LISUN EDX-3 Metal Tester in Heavy Metal Detection of Soil

Abstract: This paper focuses on the application of the LISUN EDX – 3 Portable X – ray Spectrometer, an advanced metal tester, in the detection of heavy metals in soil. With the increasing concern about soil pollution and its impact on the ecological environment and human health, accurate and efficient heavy metal detection in soil is of great significance. The LISUN EDX – 3 metal tester offers several advantages such as rapid analysis, high precision, non – destructive testing, and a wide range of elemental detection capabilities. Through detailed introduction of the instrument’s working principle, technical specifications, and practical application examples, this paper demonstrates its effectiveness and reliability in soil heavy metal detection, providing valuable reference for environmental monitoring and soil quality assessment.

1. Introduction

Soil is a vital component of the Earth’s ecosystem, serving as a medium for plant growth, a reservoir for water and nutrients, and a habitat for numerous organisms. However, in recent decades, soil pollution by heavy metals has become a serious global issue. Heavy metals such as lead (Pb), cadmium (Cd), mercury (Hg), chromium (Cr), and arsenic (As) can accumulate in the soil over time due to various human activities, including industrial production, mining, waste disposal, and the use of chemical fertilizers and pesticides.

Portable X-ray Fluorescence Spectrometer | XRF Metal Analyzer | Alloy Gold TesterEDX 3 AL2

The presence of excessive heavy metals in the soil not only affects the quality of the soil itself, reducing its fertility and microbial activity, but also poses a significant threat to human health. These heavy metals can enter the food chain through plant uptake and accumulate in the bodies of humans and animals, causing various health problems such as neurological disorders, cancer, and organ damage. Therefore, accurate and timely detection of heavy metals in soil is crucial for understanding the extent of soil pollution, implementing effective remediation measures, and safeguarding the ecological environment and human well-being.

The LISUN EDX – 3 Portable X – ray Spectrometer, also known as an XRF Metal Analyzer and Alloy Gold Tester, has emerged as a powerful tool for heavy metal detection in soil. This instrument combines advanced X – ray fluorescence technology with a portable and user – friendly design, enabling on – site and rapid analysis of heavy metals in soil samples. In the following sections, we will explore the working principle, technical specifications, and practical applications of the LISUN EDX – 3 metal tester in soil heavy metal detection.

2. Working Principle of LISUN EDX – 3 Metal Tester

The LISUN EDX – 3 metal tester operates based on the principle of X – ray fluorescence (XRF). When a sample is irradiated with X – rays from the instrument’s excitation source, the atoms in the sample absorb the X – ray energy. This causes the inner shell electrons of the atoms to be ejected, creating vacancies. Electrons from higher energy levels then fill these vacancies, emitting characteristic X – rays in the process. The energy of these characteristic X – rays is unique to each element, and by measuring the energy and intensity of the emitted X – rays, the instrument can identify and quantify the elements present in the sample.

The EDX – 3 is equipped with an imported high – precision Si – pin detector, which is highly sensitive to X – rays. The detector converts the X – ray photons into electrical signals, which are then processed by the instrument’s high – performance processor. The processor analyzes the signals to determine the energy and intensity of the X – rays, and based on this information, it identifies the elements in the sample and calculates their concentrations.

The excitation source of the EDX – 3 is a 50kV/200uA Ag target integrated micro X – ray tube and high – voltage power supply, with a matching power of ≤4W. This excitation source provides a stable and intense X – ray beam, ensuring accurate and reliable detection of heavy metals in the soil samples.

3. Technical Specifications of LISUN EDX – 3 Metal Tester

The LISUN EDX – 3 metal tester boasts a range of impressive technical specifications that make it well – suited for soil heavy metal detection. Table 1 below summarizes the key technical parameters of the instrument.

The wide range of detectable elements from sulfur to uranium ensures that all common heavy metals found in soil can be analyzed. The high – precision detector with an energy resolution of 145eV allows for accurate identification and quantification of elements. The short detection time, especially 20 seconds for major element analysis, enables rapid screening of a large number of soil samples in the field. The ppm – level detection limit and low RSD ensure the accuracy and reproducibility of the test results.

The powerful processor and ample memory, along with the large onboard data hard drive, facilitate efficient data processing and storage. The industrial – grade operating system and the ability to generate and transfer reports in multiple formats make data management and sharing convenient. The radiation safety features protect the user from potential radiation hazards, while the lightweight design and long – lasting battery make the instrument highly portable for on – site applications.

4. Application of LISUN EDX – 3 Metal Tester in Soil Heavy Metal Detection

4.1 Sampling and Sample Preparation

Before using the LISUN EDX – 3 metal tester for soil heavy metal detection, proper sampling and sample preparation are essential. Soil samples should be collected from representative locations within the area of interest. A systematic sampling method, such as grid sampling or random sampling with appropriate stratification, can be employed to ensure the representativeness of the samples.

The collected soil samples should be air – dried at room temperature to remove moisture. After drying, the samples are ground using a mortar and pestle or a mechanical grinder to obtain a fine powder. The powdered samples are then sieved through a suitable mesh size, typically 100 – 200 mesh, to ensure uniformity and to remove any large particles or debris that could affect the testing results.

4.2 On – Site Testing

One of the significant advantages of the LISUN EDX – 3 metal tester is its portability, which allows for on – site testing of soil samples. This eliminates the need for transporting samples to a laboratory, saving time and reducing the risk of sample contamination or alteration during transportation.

To perform on – site testing, the prepared soil sample is placed in a suitable sample holder provided with the instrument. The user can then select the appropriate testing mode, either the one – key trigger testing mode for quick screening or the software control mode for more detailed analysis. In the one – key trigger mode, the instrument automatically starts the analysis process when the trigger button is pressed. In the software control mode, the user can set parameters such as the detection time, voltage, and current according to the specific requirements of the test.

The instrument irradiates the soil sample with X – rays, and within 20 seconds, it provides accurate measurement results of the major heavy metal elements present in the sample. The results are displayed in real – time on the instrument’s high – performance LCD touch screen, showing the elemental composition and their respective concentrations.

4.3 Data Analysis and Interpretation

The LISUN EDX – 3 metal tester automatically stores the test data, which can be further analyzed and interpreted. The instrument can generate test reports in Excel, BMP, PDF, or CSV formats, making it easy to transfer the data to a computer for more detailed analysis.

The detected heavy metal concentrations in the soil samples can be compared with relevant soil quality standards and guidelines, such as the national soil environmental quality standards. For example, in China, the “Soil Environmental Quality – Risk Control Standards for Soil Contaminated Sites (Risk Screening Values and Risk Intervention Values for Soil Contaminants)” (GB 36600 – 2018) provides threshold values for various heavy metals in different types of soil. By comparing the measured concentrations with these standards, it is possible to determine whether the soil is contaminated by heavy metals and to what extent.

If the measured heavy metal concentrations exceed the standard values, further investigation and remediation measures may be required. The data obtained from the LISUN EDX – 3 metal tester can also be used to create spatial distribution maps of heavy metals in the soil, helping to identify hotspots of contamination and to design appropriate remediation strategies.

4.4 Comparison with Traditional Testing Methods

Traditional methods for soil heavy metal detection, such as atomic absorption spectroscopy (AAS) and inductively coupled plasma mass spectrometry (ICP – MS), often require complex sample digestion procedures and expensive laboratory equipment. These methods are time – consuming and labor – intensive, and the samples need to be transported to a well – equipped laboratory for analysis.

In contrast, the LISUN EDX – 3 metal tester offers several advantages over traditional methods. Firstly, it is a non – destructive testing method, which means that the soil samples can be tested without being chemically altered or destroyed. This is particularly beneficial when dealing with valuable or limited samples. Secondly, the on – site testing capability of the EDX – 3 allows for immediate results, enabling quick decision – making in the field. Thirdly, the instrument is relatively easy to operate, requiring less technical expertise compared to traditional laboratory – based methods. Table 2 below compares the LISUN EDX – 3 metal tester with traditional AAS and ICP – MS methods.

Although the detection limit of the LISUN EDX – 3 metal tester is at the ppm level, which is slightly higher than that of AAS and ICP – MS in some cases, its overall advantages in terms of portability, rapid analysis, and ease of operation make it a valuable tool for initial screening and on – site monitoring of soil heavy metals. In many practical applications, the ppm – level detection limit is sufficient to identify areas of potential soil contamination and to prioritize further investigation.

5. Case Studies

5.1 Case Study 1: Industrial Area Soil Monitoring

In an industrial area where multiple factories are located, soil pollution by heavy metals is a major concern. The LISUN EDX – 3 metal tester was used to conduct on – site soil sampling and testing. A total of 50 soil samples were collected from different locations within the industrial area.

The test results showed that the concentrations of lead (Pb), cadmium (Cd), and chromium (Cr) in some of the soil samples exceeded the national soil environmental quality standards. Figure 1 below shows the distribution of lead concentrations in the soil samples.

Based on the test results, further investigation was carried out to identify the sources of heavy metal pollution. It was found that some of the factories were discharging wastewater and solid waste containing heavy metals without proper treatment, which led to the contamination of the surrounding soil. Remediation measures were then implemented, including the installation of wastewater treatment facilities and the removal and disposal of contaminated soil.

5.2 Case Study 2: Agricultural Land Monitoring

In an agricultural area where chemical fertilizers and pesticides have been widely used for many years, the LISUN EDX – 3 metal tester was used to assess the heavy metal content in the soil. A total of 30 soil samples were collected from different farmlands.

The test results revealed that the concentrations of arsenic (As) and mercury (Hg) in some of the soil samples were above the acceptable levels. Figure 2 below shows the comparison of arsenic concentrations in the soil samples with the standard values.

After analyzing the data, it was determined that the excessive use of certain pesticides and fertilizers containing heavy metals was the main cause of the soil contamination. The local agricultural department recommended reducing the use of these products and promoting the use of organic fertilizers and biological pesticides to reduce the input of heavy metals into the soil.

6. Conclusion

The LISUN EDX – 3 Portable X – ray Spectrometer, as an advanced metal tester, has demonstrated excellent performance in the detection of heavy metals in soil. Its unique combination of rapid analysis, high precision, non – destructive testing, wide elemental detection range, and portability makes it an ideal tool for on – site soil monitoring and heavy metal analysis.

By using the LISUN EDX – 3 metal tester, accurate and timely information about the heavy metal content in soil can be obtained, which is crucial for understanding the extent of soil pollution, identifying pollution sources, and implementing effective remediation measures. Compared with traditional testing methods, the EDX – 3 offers significant advantages in terms of sample preparation, testing location, testing time, and operation complexity, making it accessible to a wider range of users, including environmental monitoring agencies, researchers, and field workers.

However, it should be noted that although the LISUN EDX – 3 metal tester provides valuable information about soil heavy metal concentrations, its detection limit and accuracy may have some limitations compared to more advanced laboratory – based techniques. Therefore, in some cases where extremely low levels of heavy metals need to be detected or highly accurate results are required, complementary laboratory analysis using methods such as AAS or ICP – MS may be necessary.

In conclusion, the LISUN EDX – 3 metal tester has made a significant contribution to the field of soil heavy metal detection. With the continuous development of technology, it is expected that the performance of such portable metal testers will be further improved, providing more accurate and efficient solutions for soil environmental monitoring and protection. Future research and development efforts could focus on enhancing the detection sensitivity, expanding the elemental detection range, and improving the integration of data analysis and management functions to better meet the growing needs of soil pollution monitoring and remediation.