A method for analyzing combustion products

Abstract

The present invention relates to combustion product analysis, and more specifically, to a method for combustion product analysis. The method comprises a muffle furnace, a quartz glass tube, a heating filament, a gas source, and an analytical instrument. This method can ignite substances with different ignition points and then introduce the resulting combustion gases into an analytical instrument for detection. The method has the advantages of wide applicability and simple operation.

Description

Technical Field

[0001] The present invention relates to combustion product analysis, and more specifically, to a method for combustion product analysis. The method comprises a muffle furnace, a quartz glass tube, a heating filament, a gas source, and an analytical instrument. This method can ignite substances with different ignition points and then introduce the resulting combustion gases into an analytical instrument for detection. The method has the advantages of wide applicability and simple operation. Background Art

[0002] Combustion product analysis is the scientific and technical field that studies the chemical composition and properties of various gases, particulate matter, and hazardous substances produced during combustion. During combustion, such as burning fossil fuels, wood, biomass, or other combustible materials, a large number of gases and particulate matter are produced. These include carbon dioxide, carbon monoxide, nitrogen oxides, sulfur oxides, volatile organic compounds, and some incomplete combustion products, such as polycyclic aromatic hydrocarbons, heavy metals, and other hazardous substances.

[0003] Combustion product analysis is a field of study aimed at understanding the characteristics of combustion processes, controlling combustion emissions, and assessing their environmental impacts. It has a wide range of applications in environmental science, atmospheric science, energy science, engineering technology, and other fields. Studying the composition and characteristics of combustion products can help us better understand the chemical reaction mechanisms involved in combustion, optimize combustion processes to reduce pollutant emissions, and assess and monitor their impacts on the environment and human health.

[0004] Commonly used techniques for modern combustion product analysis include mass spectrometry, chromatography, spectroscopy, and mass spectrometry-hybrid technology. These methods can accurately measure the concentrations of various gases and particulate matter, providing an important scientific basis for environmental protection and air quality improvement. With the continuous development of technology, combustion product analysis will continue to contribute to the promotion of green environmental development and sustainable energy utilization. Summary of the Invention

[0005] The object of the present invention is to provide a simple and easy-to-operate combustion product analysis method.

[0006] To achieve the above object, the technical solution of the present invention is:

[0007] A method for analyzing combustion products, the device used includes a gas source, a sampling glass tube, a sample injection glass tube, and an analytical instrument; the sample injection glass tube with two open ends is formed by connecting two sections of pipes with different inner diameters in series, a metal capillary tube with two open ends is inserted into the section with the smaller inner diameter, one end of the metal capillary tube extends into the sample injection glass tube, and the other end is connected to the sample injection port of the analytical instrument; the middle portion of the sample injection glass tube (at the intersection of the section with the smaller inner diameter and the section with the larger inner diameter) is placed in a muffle furnace, and both open ends are located outside the muffle furnace. An electric heating wire is wrapped around the outer wall of the sample injection glass tube section with the smaller inner diameter located outside the muffle furnace;

[0008] One end of the sampling glass tube with two openings is connected to the outlet of the gas source, and the other end is inserted into the larger inner diameter section of the sampling glass tube from the open end on the side with the larger inner diameter; the characteristics are:

[0009] Take 1-5g of the combustion product sample to be tested and place it in a sampling glass tube 1-2cm away from the open end of the sampling glass tube that will be inserted into the injection glass tube. Stuff a ball of glass wool into the open end of the sampling glass tube that will be inserted into the injection glass tube to seal it to prevent particles generated by combustion from flowing out of the sampling glass tube and contaminating the analytical instrument.

[0010] Then, one end of the sampling glass tube is inserted into the sampling glass tube nested in the muffle furnace near the intersection of two sections of pipes with different inner diameters;

[0011] The other end of the sampling glass tube is connected to the gas source, and the sampling glass tube is connected to the analytical instrument through a metal capillary for detection.

[0012] The sampling glass tube with two open ends is made up of two sections of pipes with different inner diameters connected in series. The sampling glass tube is 10-20 cm long and has different diameters at both ends. The diameter changes in the middle of the glass tube. The thin end has an outer diameter of 3mm-4mm (such as 3mm or 4mm) and an inner diameter of 1.5-2mm, and the thick end has an outer diameter of 10-12mm and an inner diameter of 8-10mm. The open end on the side with the larger inner diameter is inserted into the middle of the sampling glass tube, and the open end on the side with the smaller inner diameter is connected to the outlet of the gas source.

[0013] The length of the sampling glass tube is 10-20 cm, and the two ends also have different diameters. The diameter changes in the middle of the glass tube. The outer diameter of the thin end is 3mm-4mm (such as: 3mm or 4mm), and the inner diameter is 1.5-2mm. The outer diameter of the thick end is 14-16mm, and the inner diameter is 12-14mm.

[0014] The heating temperature range of the muffle furnace is 25-500℃; the ceramic heating coil (Huajian Electric Heating, 220V, 1400W) inside it is located in the center of the muffle furnace, and the diameter reduction position of the sample feeding glass tube (that is, the intersection of two sections of pipes with different inner diameters) is nested in the middle of the ceramic heating coil.

[0015] When analyzing the gases produced by combustion, the end of the sampling glass tube with a smaller diameter is connected to the gas source through an SMC gas pipe connector. A Seven Star D07-19B mass flow controller is installed on the connecting pipe to regulate the gas flow rate, which is 5-50 ml / min. The gas in the gas source is air and / or nitrogen.

[0016] Insert a metal capillary with an outer diameter of 1 / 16 into the end of the injection glass tube with a smaller diameter for connecting to the analytical instrument for detection;

[0017] The outer wall of the sampling glass tube with a metal capillary inserted therein is wrapped with an electric heating wire for insulation to reduce the adsorption of combustion products. The insulation temperature is 25-300°C.

[0018] The analytical instrument can be a chromatograph, mass spectrometer or ion mobility spectrometer.

[0019] The gas flow rate through the mass flow controller, the heating temperature of the muffle furnace, and the heating temperature of the heating wire are all set and read by the control computer.

[0020] This method can ignite substances with different ignition points in a muffle furnace, and then introduce the generated gases into an analytical instrument for detection. It has the advantages of wide application range and simple operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of the structure of a method for combustion product analysis of the present invention;

[0022] Figure 2 Mass spectra of three types of heat-not-burn cigarette tobacco; DETAILED DESCRIPTION

[0023] See also Figure 1 , which is a structural diagram of the present invention.

[0024] The device includes a gas source 1, a sampling glass tube 4, a sample injection glass tube 5, and an analytical instrument 12. The sample injection glass tube 5, which is open at both ends, is composed of two sections of pipes with different inner diameters connected in series. A metal capillary tube 11, which is open at both ends, is inserted into the section with the smaller inner diameter. One end of the metal capillary tube 11 extends into the sample injection glass tube 5, and the other end is connected to the sample inlet of the analytical instrument 12. The middle portion of the sample injection glass tube 5 (at the intersection of the section with the smaller inner diameter and the section with the larger inner diameter) is placed in a muffle furnace 6, and its two open ends are located outside the muffle furnace 6. An electric heating wire 10 is wrapped around the outer wall of the section with the smaller inner diameter of the sample injection glass tube 5 outside the muffle furnace 6.

[0025] One end of the sampling glass tube 4 with two open ends is connected to the outlet of the gas source 1, and the other end is inserted into the larger inner diameter section of the sampling glass tube 5 from the open end on the side with the larger inner diameter;

[0026] Take 2g of the combustion product sample 8 to be tested and place it in the sampling glass tube 4 1.5cm away from the open end of the sampling glass tube 4 to be inserted into the injection glass tube 5. Stuff a ball of glass wool 9 into the open end of the sampling glass tube 4 to seal it to prevent particles generated by combustion from flowing out of the sampling glass tube 4 and contaminating the analysis instrument 12.

[0027] Then insert one end of the sampling glass tube 4 into the sampling glass tube 5 nested in the muffle furnace 6 near the intersection of two sections of pipes with different inner diameters;

[0028] The other end of the sampling glass tube 4 is connected to the gas source 1, and the sampling glass tube 5 is connected to the analysis instrument 12 through the metal capillary 11 for detection.

[0029] The sampling glass tube 4, open at both ends, is composed of two sections of pipes with different inner diameters connected in series. The sampling glass tube 4 is 20 cm long and has different diameters at both ends. The diameter changes in the middle of the glass tube. The thin end has an outer diameter of 3 mm and an inner diameter of 1.5 mm, while the thick end has an outer diameter of 11 mm and an inner diameter of 9 mm. The open end with the larger inner diameter is inserted into the middle of the sampling glass tube 5, and the open end with the smaller inner diameter is connected to the outlet of the gas source 1.

[0030] The injection glass tube 5 is 20 cm long and has different diameters at both ends. The diameter changes in the middle of the glass tube. The outer diameter of the thin end is 3 mm and the inner diameter is 1.5 mm, while the outer diameter of the thick end is 14 mm and the inner diameter is 12 mm.

[0031] The heating temperature of the muffle furnace 6 is 300°C; the ceramic heating ring (Huajian electric heating, 220V, 1400W) 7 inside it is located in the center of the muffle furnace 6, and the diameter-changing position of the sampling glass tube 5 (i.e., the intersection of two sections of pipelines with different inner diameters) is nested in the middle of the ceramic heating ring 7.

[0032] When analyzing the gas generated by combustion, the end of the sampling glass tube 4 with a smaller diameter is connected to the gas source 1 through the SMC gas pipe connector 3, and a Seven Star D07-19B mass flow controller (2) is provided on the connecting pipe to regulate the gas flow rate, which is 20 ml / min. The gas in the gas source 1 is nitrogen.

[0033] A metal capillary 11 with an outer diameter of 1 / 16 is inserted into the end of the sample injection glass tube 5 with a smaller diameter for connecting to an analytical instrument 12 for detection;

[0034] An electric heating wire 10 is wound around the outer wall of the portion of the sampling glass tube 5 into which the metal capillary 11 is inserted, which extends out from the muffle furnace (6), for heat preservation to reduce the adsorption of combustion products. The heat preservation temperature is 200°C.

[0035] The analytical instrument used was mass spectrometry.

[0036] The gas flow rate through the mass flow controller 2 , the heating temperature of the muffle furnace 6 , and the heating temperature of the heating wire 10 are all set and read by the control computer 13 .

[0037] Example:

[0038] Using the above-mentioned sampling method and experimental conditions, the combustion components of 1g of Huanghelou brand heat-not-burn cigarette tobacco were analyzed with the muffle furnace heating temperature set at 300℃. Figure 2 As shown in the mass spectrum, the substances detected mainly include nicotine, methylfurfural, dihydroxybenzene, ethylene, acetone, pyrrole, pyridine, benzene, toluene, xylene, ammonia, nitric oxide, methyl mercaptan, cyclopentene, methylfuran, aniline, phenol and other compounds.

Claims

1. A method for analyzing combustion products, the device used comprises a gas source (1), a sampling glass tube (4), a sampling glass tube (5), and an analytical instrument (12); the sampling glass tube (5) with two open ends is formed by connecting two sections of pipes with different inner diameters in series, a metal capillary (11) with two open ends is inserted into the section with the smaller inner diameter, one end of the metal capillary (11) extends into the sampling glass tube (5), and the other end is connected to the sampling port of the analytical instrument (12); the middle part of the sampling glass tube (5) (at the intersection of the section with the smaller inner diameter and the section with the larger inner diameter) is placed in a muffle furnace (6), and the two open ends are both located outside the muffle furnace (6); an electric heating wire (10) is wound around the outer wall of the section with the smaller inner diameter of the sampling glass tube (5) outside the muffle furnace (6); One end of the sampling glass tube (4) with two openings is connected to the outlet of the gas source (1), and the other end is inserted into a section of the sampling glass tube (5) with a larger inner diameter from the open end on the side with a larger inner diameter; the characteristics are: 1-5 g of a combustion product sample (8) to be tested is placed in a sampling glass tube (4) 1-2 cm away from the open end of the sampling glass tube (4) to be inserted into the injection glass tube (5), and a ball of glass wool (9) is inserted into the open end of the sampling glass tube (4) to be inserted into the injection glass tube (5) to seal it, so as to prevent particles generated by combustion from flowing out of the sampling glass tube (4) and contaminating the analysis instrument (12); Then, one end of the sampling glass tube (4) is inserted into the sampling glass tube (5) nested in the muffle furnace (6) near the intersection of two sections of pipes with different inner diameters; The other end of the sampling glass tube (4) is connected to the gas source (1), and the sampling glass tube (5) is connected to the analysis instrument (12) via the metal capillary (11) for detection.

2. The method according to claim 1, wherein: The sampling glass tube (4) with two open ends is formed by connecting two sections of pipes with different inner diameters in series. The sampling glass tube (4) is 10-20 cm long and has different diameters at both ends. The diameter changes in the middle of the glass tube. The outer diameter of the thin end is 3 mm-4 mm (e.g., 3 mm or 4 mm) and the inner diameter is 1.5-2 mm. The outer diameter of the thick end is 10-12 mm and the inner diameter is 8-10 mm. The open end on the side with the larger inner diameter is inserted into the middle of the sampling glass tube (5), and the open end on the side with the smaller inner diameter is connected to the outlet of the gas source (1). The length of the sampling glass tube (5) is 10-20 cm, and the two ends also have different diameters. The diameter changes in the middle of the glass tube. The outer diameter of the thin end is 3mm-4mm (such as 3mm or 4mm) and the inner diameter is 1.5-2mm. The outer diameter of the thick end is 14-16mm and the inner diameter is 12-14mm.

3. The method according to claim 1 or 2, characterized in that: The heating temperature range of the muffle furnace (6) is 25-500°C; the ceramic heating coil (Huajian Electric Heating, 220V, 1400W) (7) therein is located at the center of the muffle furnace (6), and the diameter-changing position of the sample feeding glass tube (5) (i.e., the intersection of two sections of pipes with different inner diameters) is nested in the middle of the ceramic heating coil (7).

4. The method according to claim 1 or 2, characterized in that: When analyzing the gas generated by combustion, the end of the sampling glass tube (4) with a smaller diameter is connected to the gas source (1) through the SMC gas pipe connector (3), and a Seven Star D07-19B mass flow controller (2) is provided on the connecting pipe to regulate the gas flow rate, which is 5-50 ml / min. The gas in the gas source (1) is air and / or nitrogen.

5. The method according to claim 1 or 2, characterized in that: A metal capillary (11) with an outer diameter of 1 / 16 is inserted into the end of the sample injection glass tube (5) with a smaller diameter for connecting to an analytical instrument (12) for detection; An electric heating wire (10) is wound around the outer wall of the sampling glass tube (5) inserted with a metal capillary (11) extending from the muffle furnace (6) for heat preservation to reduce the adsorption of combustion products. The heat preservation temperature is 25-300°C.

6. The method according to claim 1, wherein: The analytical instrument (12) may be a chromatograph, a mass spectrometer or an ion mobility spectrometer.

7. The method according to claim 1, 4 or 5, characterized in that: The gas flow rate through the mass flow controller (2), the heating temperature of the muffle furnace (6), and the heating temperature of the heating wire (10) are all set and read through the control computer (13).

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