XOM-10L Microwave Ashing Sample Pre treatment System

The XOM-10L microwave ashing sample pretreatment system adopts microwave ashing technology, which is simple, fast, and accurate for both ash content measurement and dry ashing measurement of impurity metal elements in sample processing. The combination of microwave ashing with high-temperature heating and microwave technology greatly saves working time compared to traditional methods.

2XOM-10L Microwave Ashing Sample Pre treatment SystemDevice Configuration

2.1 Host 1 unit

2.2 Exhaust gas purification system 1 set

2.3 One 10 liter specially made quartz crucible; Additionally, it comes with 10 or more silicon carbide crucibles and 2 pairs of insulated gloves

3. Technical indicators

3.1 Power supply: 380V ± 10V, 50Hz ± 1Hz

3.2 Microwave power: 0-4800W closed-loop PID power control, continuously adjustable; The microwave feeding points are located on both sides and behind the microwave cavity

3.3 Temperature measurement system: thermocouple temperature measurement, working temperature range of 0-900 ℃, temperature measurement accuracy of ± 1 ℃, maximum temperature of 1200 ℃; Users can choose the infrared temperature measurement method, which does not contaminate the sample and is more accurate

3.4 Microwave ashing oven with an inner cavity capacity of ≥ 56L; high-performance crucible with a capacity of 10L, capable of withstanding rapid cooling and heating from 0 to 1000 ℃, without cracking or powder falling

3.5 Intelligence: Integrating microwave drying, carbonization, and ashing, the system automatically controls the drying, carbonization, and ashing processes

3.6 System Control: PLC color touch screen intelligent control, can store 80 methods, each method can set 5 or more heating programs, record experimental data throughout the process, the control system comes with a USB interface for easy reading of the entire control process, and experimental data can be exported;

3.7 Microwave and auxiliary heating in one: Microwave heating and auxiliary heating work together to achieve more uniform ashing;

The 3.8 high-capacity biological sample ashing device is connected to the exhaust gas purification system, which is efficient, reliable, practical, and effective. Divided into three levels of processing system, first level oil fume separator; The secondary ultraviolet photocatalytic degradation system is mainly aimed at the carbonization stage. Microwave infinite ultraviolet photocatalytic oxidation technology is used to degrade pollutants. Through the combined action of microwave, ultraviolet, ozone, and OH · (hydroxyl radicals) on pollutants, photocatalytic oxidation reactions occur, decomposing pollutants and generating harmless substances such as CO2 and H2O for emission; Third level activated carbon fiber and granular activated carbon adsorption device. Three parts work in series and collaboratively.

3.9 Precision and safety: The internal safety locking mechanism can automatically stop the operation of the instrument in case of unexpected situations. The microwave leakage prevention adopts inductive suppressors, and the microwave leakage rate is less than 5mw/cm2 (national standard)

3.10 Cooling method: High speed centrifugal fan air cooling working time: can withstand continuous operation for 24 hours

3.11 Equipment composition: mainly composed of microwave high-temperature system, atmosphere control system, electrical control system and other accessories

3.12 Microwave high-temperature system enables materials to complete three processes of drying, carbonization, and ashing in a continuous process. Among them, the dehydration and drying stage quickly completes dehydration under low temperature conditions, avoiding the effects of prolonged time and high temperature on nuclide sublimation and drift under traditional drying conditions. During the pyrolysis carbonization stage, the dry powder of the dehydrated material continues to undergo pyrolysis reaction under low oxygen conditions, and the gas is discharged until it is completely carbonized. During the ashing stage, the equipment begins to introduce air, and high-temperature carbides begin to oxidize and decompose until they are completely ashed

3.13 The microwave high-temperature system mainly consists of a specially designed microwave heating large capacity crucible, microwave heating chamber, microwave source, temperature measuring thermocouple, insulation system, etc

3.14 Special customized crucible, capable of holding materials with an enlarged volume of 10L

3.15 The microwave heating chamber is mainly made of stainless steel 304 welded together, and microwave sources are installed on the periphery, sides, and rear of the chamber

3.16 The microwave source mainly consists of a magnetron, a high-voltage transformer, a high-voltage rectifier circuit, a cooling fan, and an overcurrent protection device

The main function of the 3.17 temperature measuring thermocouple is to test the actual temperature of the material and link it with the temperature control system

3.18 The insulation system is composed of materials with good insulation effect and low dielectric constant, designed as three-layer insulation

3.19 Atmosphere control system: The atmosphere control system automatically controls the intake and exhaust during the experimental process, and automatically controls according to the experimental process. During the dehydration and drying stage, the moisture in the material is discharged from the equipment; During the pyrolysis carbonization stage, control the intake air to keep the material in a lean oxygen environment; During the ashing stage, control the introduction of air to initiate the oxidation and decomposition of high-temperature carbides;

3.20 Atmosphere control: Automatic switching of fan opening and closing during drying, carbonization, and ashing

The control system mainly adopts PLC program control, and the operating parameters can be modified according to different working conditions. Mainly composed of PLC programming controller, data acquisition system, color touch screen, thermocouple sensor and other components

3.22 PLC programming controller: Collect various data and perform calculations, judgments, and issue instructions to each part

3.23 Data acquisition system: Various data are collected and transmitted to the controller, which calculates and issues instructions based on the data. During the microwave heating process, thermocouple data is collected, and the PLC can manually and automatically control it through this data acquisition, facilitating process interpretation

3.24 Color Touch Screen: Control screen, where operators can set various indicator parameters on the control screen

3.25 Thermocouple Sensor: Collect and transmit the temperature measurement results of the thermocouple to the controller. As some nuclides can sublime at low temperatures, precise temperature control is required, and the ashing temperature of the entire process flow needs to be controlled to prevent nuclide sublimation and overflow

3.26 adopts a temperature controller to protect the core components of the microwave source and extend its service life. The magnetron adopts today's multi-source and multi port broadband feeding to ensure heat balance inside the box; *The independent control and protection circuit ensures that the use of each component does not interfere with each other; The design and installation of the equipment generally consider the requirements of safety, stability, reliability, hygiene, ease of operation, and maintenance.

Example of ashing

1、 Ashing of scallops

Experimental objective: To convert fresh scallop samples into grey samples and calculate the grey to fresh ratio

Experimental materials: Large capacity microwave ashing oven, electronic balance, mortar, sieve

Experimental procedure:
1. Set the stage of removing a large amount of moisture at 120 ℃ for 1 hour
2.160 ℃, 1h, start carbonization
3.200℃， 1h，
4.280℃， 1h，
5.350℃， 2h，
6.400℃， 2h，
7.450 ℃, ashing for 27 hours, ashing completed

Results and Discussion
1. Ash to fresh ratio=87.7g/2.40kg=36.3g/kg
2. Drying and carbonization take 8 hours, and ashing takes 27 hours. It takes 35 hours from fresh sample to ash sample.

2、 The ashing of bird shells

Experimental objective: To convert fresh bird shell samples into grey samples and calculate the grey to fresh ratio

Experimental instruments: large capacity microwave ashing oven, electronic balance, mortar, sieve

Experimental process:
1. Set the stage of removing a large amount of moisture at 120 ℃ for 1 hour
2.160 ℃, 1h, carbonization
3.200℃， 1h
4.280℃， 1h
5.350℃， 2h
6.400℃， 2h
7.450 ℃, ashing for 24 hours, ashing completed

Results and Discussion
1. Ash to fresh ratio=105.25g/2.83kg=37.19g/kg
2. Drying and carbonization take 8 hours, and ashing takes 24 hours. It takes 32 hours from fresh sample to ash sample.

3、 Ashing of Eagle Claw Shrimp

Experimental objective: To make grey samples from fresh eagle claw shrimp and calculate the grey to fresh ratio

Experimental materials: Vertical microwave ashing oven, electronic balance, mortar, sieve

Experimental process:
1. Set 105 ℃ for 20 minutes to remove a large amount of moisture
2.120℃， 1h
3.160 ℃, 1h, carbonization (close the intake when reaching 160 ℃)
4.200℃， 1h
5.280℃， 1h
6.350℃， 2h，
7.400℃， 2h，
8.450 ℃, ashing for 44 hours, ashing completed

Results and Discussion
1. Ash to fresh ratio=217.6g/kg (2.230+0.865) kg=70.2g/kg
2. Drying and carbonization take 8 hours and 20 minutes, while ashing takes 44 hours. It takes 52 hours from fresh sample to ash sample. There is no flipping throughout the process, and after carbonization is completed, the ashing speed can be accelerated by grinding the carbon finely, which can shorten the ashing time by 20 hours.

4 Detection of pork nuclide microwave ashing pretreatment