GB 25035-2010Dimethyl ether for city gas (English PDF)

3.1 The quality of dimethyl ether for city gas shall meet the requirements of

Table 1.

3.3 The dimethyl ether for city gas shall be stinky.

3.4 The odorant should be tetrahydrothiophene. The amount of odor shall be

greater than 30 mg/m3.

4.1 The testing of the mass fraction of dimethyl ether and methanol in dimethyl

ether for city gas may be carried out in accordance with the provisions of

Appendix B.

4.2 The testing of quality fraction of water in dimethyl ether for city gas shall be

carried out in accordance with the provisions of GB/T 7376.

5.1 Production inspection

When one of the following conditions occurs, the dimethyl ether for city gas

shall be fully tested according to the requirements of Table 2.

5.2 Exit-factory inspection

When dimethyl ether for city gas is exit-factory, it shall be inspected according

to the requirements of Table 2.

6.1 The facilities and accessories for storage, transportation, filling of dimethyl

ether for city gas shall be resistant to the corrosion of dimethyl ether.

6.3 The marking and packaging of dimethyl ether for city gas shall be indicated

of the words such as "flammable goods" and "no smoking".

6.4 Dimethyl ether for city gas may be transported in railway tankers,

automobile tankers, cylinder cars, ship cabins or pipeline delivered.

6.5 The railway tankers, automobile tankers, ship cabins used for transporting

dimethyl ether for city gas shall have the words such as "flammable goods" and

"no smoking".

6.6 The storage place for dimethyl ether for city gas shall comply with the

relevant provisions of GB 50016 and GB 50028.

Appendix A

(Informative)

Physical-chemical properties of dimethyl ether

The physical-chemical properties of dimethyl ether are as shown in Table A.1.

Appendix B

(Informative)

Gas chromatographic analysis method for dimethyl ether and methanol

in dimethyl ether for city gas

B.1 Scope

This Appendix gives typical working conditions for gas chromatographic

analysis of the mass fraction of dimethyl ether and methanol in dimethyl ether

for city gas. It may also use other chromatographic conditions to achieve

equivalent or higher analytical results.

B.2 Principle of method

Use a gas chromatograph which is equipped with a thermal conductivity

detector (TCD) to, under selected chromatographic conditions, through a gas

chromatographic column, separate dimethyl ether, methanol, carbon dioxide

from the dimethyl ether sample for city gas. Use a detector to detect it. Use

recorder, integrator or microprocessor to record the peak area data of each

component.

B.3 Sampling

It is performed according to the provisions of GB/T 10410.The temperature of

the gasification water bath is 70 °C ~ 90 °C.

B.4 Gas Chromatograph

Gas chromatograph which is equipped with thermal conductivity detector. It

uses gas six-way valve injector to inject sample. The material is stainless-steel.

B.5 Standard gas

......