HJ/T 38-1999 Determination of non-methane total hydrocarbons in exhaust gas from stationary pollution sources
HJ/T 38-1999 Determination of non-methane total hydrocarbons in exhaust gas from stationary pollution sources Detailed information:

Name: Packed Column 1

Stationary phase: polymer beads

Granularity: 60-80 mesh

Specifications: 0.8m*1/8

Model: Porapak Q



Name: Packed Column 1

Stationary phase: polymer beads

Granularity: 60-80 mesh

Specifications: 1.5m*1/8

Model: Porapak Q

Application: HJ/T 38-1999 Determination of non-methane total hydrocarbons in exhaust gas from stationary pollution sources-Gas chromatography

1 Scope of application

1.1 This standard is applicable to the determination of non-methane total hydrocarbons (NMHC) from fixed sources of organized and unorganized emissions.

1.2 The detection limit of NMHC is 4x10-2ng. When the chromatographic injection volume is 1.0ml, the detection concentration of the method is 4x10-2mg/m3, and the quantitative determination concentration range of the method is 0.12~32mg/m3.

2 Definitions

Non-methane hydrocarbons (NMHC): refers to the general term for hydrocarbons other than methane (mainly C2~C8). The NMHC measured under the conditions specified in this standard is the total amount of hydrocarbons other than methane that have a significant response to the gas chromatographic hydrogen flame ionization detector, measured in carbon.

3 Principles of the method

Using a gas chromatograph with a double-column double-hydrogen flame ionization detector and injecting the sample directly with a syringe, the total hydrocarbon and methane content in the sample were measured respectively, and the total non-methane hydrocarbon content was obtained from the difference between the two. At the same time, the blank value of oxygen was obtained by removing hydrocarbon air to deduct the interference of oxygen peaks in the chromatographic peaks of total hydrocarbons.

4 Reference Standards

The following standards contain provisions which, through reference in this standard, constitute provisions of this standard

GB 16297-1996 Comprehensive emission standard of air pollutants

GB 16157-1996 Determination of particulate matter in exhaust gas from stationary pollution sources and sampling methods for air pollutants

5 Reagents and Materials

Unless otherwise stated, analytical reagents and distilled water that meet national standards were used in the analysis.

5.1 Silicone.

5.2 SA molecular sieve.

5.3 Activated carbon: 15#.

After soaking with 6mol/L hydrochloric acid solution (5.6) for 12h, wash with water until neutral, and dry at 105℃ for later use.

5.4 Hydrochloric acid: ρ=1.19g/ml.

5.5 Phosphoric acid: ρ=1.71g/ml.

5.6 Hydrochloric acid solution: 1+1.

5.7 Phosphoric acid solution: (H3PO4)=3.3mol/L.

Measure ρ=1.75g/ml phosphoric acid (5.5) 38ml with a measuring cylinder, slowly pour it into water, and then dilute with water to 100ml.

5.8 Hydrogen: purified by 5A molecular sieve (5.2), activated carbon (5.3) and silica gel (5.1).