APPLICATION OF THE BIOMASS PYROLISIS PRODUCTS AS A REBURNING FUEL FOR NITROGEN OXIDES REDUCTION: TESTING THE CHEMICAL KINETICS MECHANISM

The mechanisms of chemical kinetics of the Reburning process using pyrolysis gases as a reburn fuel are determined. It has been shown that CO, CO2, H2 have very little effect on the reduction of the nitrogen oxides under conditions characteristic for the coal combustion, and hydrocarbons play the major contribution to the reduction of the nitrogen oxides. The results of the test calculations showed that the process of the nitrogen oxides reduction by the biomass pyrolysis products can be calculated by a simplified mechanism of the chemical kinetics of the Reburning process by replacing hydrocarbons with one substance (with a close carbon/hydrogen ratio as in the real pyrolysis gas mixture), provided that the mass fraction of carbon is preserved, fed to the reduction of nitrogen oxides unchanged. This approach significantly reduces machine time and calculates the nitrogen oxides reducing efficiency by Reburning technology with an accuracy of 17%.

Single Solution That Reduces Power Plants Heat Rates, Emissions, and Operating Costs

This article presents background and the test results for a NOx control solution applicable to pulverized coal-fired power plants (E-NOx) that resolve the operating challenges related to the use of low/ultra-low-NOx burners (LNB) for in-furnace control and SCR or SNCR for post-combustion nitrogen oxides reduction. The major results of CFD modeling and test data are presented, which confirm E-NOx capabilities to reduce NOx and consequently the consumption of ammonia/urea for units using post-combustion NOx control. Basic steam plant performance analysis per ASME codes in combination with test data suggested an appreciable reduction in the plant heat rate. The results of economic studies of E-NOx applications for power plants with different means of NOx control are presented in this article, demonstrating a simple payback period to be within 8–16 months. This is the first environmental technology that pays for itself thanks to a decrease in both fuel and NOx reducing reactants consumption, thus lowering operating and maintenance costs in comparison with best available current and retrofit technologies.

Differential kinetics of nitrogen oxides reduction leads to elevated nitrous oxide production by a nitrite fed granular denitrifying EBPR bioreactor

Batch kinetic assays of DPAO-enriched biomass reveal elevated kinetics when nitrite is supplied for P uptake, but extremely slow kinetics for reduction of the potent greenhouse gas nitrous oxide.