Experimental Study of the Influence of Natural Gas Constituents on CO Emission from Chinese Gas Cooker

Abstract

In China, it has become a more common practice to introduce natural gases from different sources into the same distribution system to improve supply security and reliability. Variable gas constituents may cause a negative impact on the performance of domestic gas appliances. This paper aims to study the CO emission of a Chinese gas cooker under different constituents of natural gas. A typical Chinese gas cooker with two burners, each of which has a nominal heat input of 3.8 kW, was selected. One of the burners was modified to a forced-mixed mode to replace primary air injection. Within operational ranges corresponding to the permissible Wobbe index—namely, primary air coefficients and heat inputs—the equivalence between original gas and the CH4/C3H8/N2 three-component mixture in terms of CO emission was experimentally validated. Then, different three-component mixtures were input into the other unmodified burner, which operates under injected primary air, to investigate how the CO emission changed with different gas constituents. It was found that the CO emission of a natural gas and a CH4/C3H8/N2 three-component mixture, in terms of CO emission, were equivalent. The combination of the two indexes, W and PN, can describe the CO emission from a gas cooker accurately. By means of a three-component mixture, the empirical formula, which can correlate CO and the gas property parameters, was proposed. A set of equal-CO lines was revealed for a given initial primary air adjustment. Finally, a feasible approach to manage gas quality management in China was put forward, and the conclusion can help control the CO emission of gas cookers and improve indoor air quality.