METHOD FOR HIGH-TEMPERATURE NON-CATALYTIC REMOVAL OF NITROGEN OXIDES FROM COMBUSTION PRODUCTS WITH MULTI-ZONE INPUT OF REDUCING AGENT

摘要

FIELD: chemistry.SUBSTANCE: invention relates to high-temperature purification of combustion products of all types of organic fuel from nitrogen oxides (NO) via selective non-catalytic reduction thereof. A method for high-temperature purification of combustion products in the exhaust duct of a thermal generating unit from nitrogen oxides via selective non-catalytic reduction thereof includes feeding an ammonia-containing reducing agent into selected zones of the exhaust duct that are bounded by the temperature range of 850 - 1100°C. The method is characterised by that the reducing agent is simultaneously fed into all said selected zones, where in each of said zones the reducing agent is fed with a flow coefficient of less than one relative to the stoichiometric flow rate. The number of the reducing agent input zones is preferably 2-5. The flow coefficient of the reducing agent fed into each purification zone is preferably in the range of 0.2-0.8. The reducing agent is preferably ammonia or carbamide.EFFECT: providing a maximum degree of reduction of NOwithout exceeding the stoichiometric ratio of the flow of the reducing agent.5 cl, 1 dwg, 4 tbl