Experimental Evaluation of a Low NOx LBG Combustor Using Bypass Air

Abstract

A 150-MW, 1300°C (1573 K) class gas turbine combustor firing coalgasified fuel has been designed. Main purpose of the present paper is first to estimate CO and NOx emissions, and second to discuss the low NOx combusion technology burning such a low-BTU gas. The full-scale, atmospheric-pressure combustion tests were conducted over a wide range of conditions using bypass air.The results are summarized as follows: (1) A designed combustor has an excellent combustion efficiency of 99.6 percent even when the calorific value of fuel drops to 650 kcal/m 3 N.(2) CO and NOx emissions can be estimated by the air ratio in primary combustion zone. (3) The role of air bypass valve is important for low NOx combustion, and to give stable combustion at lower load conditions. (4) Ammonia conversion to NOx is minimized with a optimum air ratio in primary combustion zone.

Performance and Emission Levels in Gas Turbine Plants

“…The examples also compare the influence of fuel burned. For both cases four fuels were examined: methane and three different coal derived fuels, G1 -G3 (De la Mora et al , 1985, Nakata et al , 1990, whose composition is reported in The pressure ratios of the two gas turbines (the T.I.T. being essentially the same) led, as expected, to higher efficiency levels for the LM 1600, while the heavy duty turbine presents better values for specific power and second law efficiency, that make possible a more favorable use in combined plants (Table 2).…”

“…In fact, some tendencies which could improve performance would also cause a very high increase in emissions. Hence, the systems for NO x abatement are proving to be increasingly more expensive as regards both the more accurate fluid-dynamic design of combustion chamber (mainly in the case of dry combustors) and the consumption of demineralized injected water or steam (Aoyama and Mandai, 1984, Cerri and Arsuffi, 1988, Fitts et al , 1990, Nakata et al , 1990, Sato et al, 1990, Kreitmeier at al., 1991.…”

“…The model also accounts for the effects of water or steam injection into the combustor. A more realistic comparison among the several fuels is made possible by some empirical correlations (Nakata et al, 1990) which were employed to predict fuel NO x formation.…”

Design and Test of a Low-NOx Advanced Rich-Lean Combustor for LBG Fueled 1300°C-Class Gas Turbine

“…Since the CDG fuel has a low heating value and contains a high percentage of inert gases, its flame temperature is low. Figure 1 compares adiabatic flame temperatures of LBG and CH 4 . The flame temperature of CH4, with air preheated at 370°C, reaches its highest level of 2100°C.…”