SCR Flue Gas Denitrification Technology for Industrial NOx Emission Control
Product Details
SCR Flue Gas Denitrification Technology for Industrial NOx Emission Control
Technology Overview
SCR (Selective Catalytic Reduction) is a mature flue gas denitrification technology. The denitrification system typically consists of an ammonia preparation system, an ammonia/air mixing device, a reactor containing catalyst, and a control system. The SCR reactor is installed between the boiler economizer and the air preheater. The operating temperature range is 320 to 400 degrees Celsius.
Ammonia is diluted in the ammonia/air mixing device before injection into the flue duct. The ammonia/ flue gas mixing device ensures thorough mixing of ammonia with the boiler flue gas. The mixed gas then enters the reactor. Within the reactor, the gas passes through catalyst layers. Under the action of the catalyst, nitrogen oxides (NOx) react with ammonia (NH₃) to produce harmless nitrogen (N₂) and water (H₂O). This chemical reaction removes nitrogen oxides from the boiler flue gas.
Process Advantages
Simple Structure with High Denitrification Efficiency
The SCR system has a straightforward design. Flue gas flows through the catalyst layers while ammonia is injected upstream. There are no moving parts inside the reactor besides the gas flow itself. This simple structure results in reliable operation. Denitrification efficiency is high, typically achieving 80 to 95 percent removal depending on catalyst volume and operating conditions.
Flexible Ammonia Preparation
Ammonia can be prepared from either anhydrous liquid ammonia or urea. Liquid ammonia systems have lower capital cost but require stricter safety measures. Urea systems are safer but have higher operating costs. Both options are available depending on customer preference and local regulations.
Shared Ammonia Storage for Chemical Plants
Chemical plants with both SCR denitrification and ammonia-based flue gas desulfurization can share a common ammonia storage and supply system. This reduces equipment duplication, lowers capital investment, and simplifies site logistics.
Easy Maintenance
The SCR system requires periodic catalyst replacement. Catalyst life typically ranges from 16,000 to 24,000 operating hours depending on flue gas composition. Access doors and internal walkways are provided for inspection and maintenance. The ammonia injection grid includes removable lances for cleaning.
Customized Implementation
Haihui provides specific implementation plans based on each customer’s actual site conditions, flue gas characteristics, and NOx reduction requirements.
