Introduction
The document discusses the Dry Scrubbing System with lime, a solution for cleaning flue gas generated from the combustion of solid wastes such as municipal or industrial waste, or RDF (Refuse Derived Fuel). The flue gas contains pollutants like acid components, dust, heavy metals, nitrogen oxides, polyaromatic compounds, and products of incomplete combustion, which pose risks to human health and the environment.

System Overview
The Dry Scrubbing System involves injecting hydrated lime and activated carbon into a venturi reactor, with residue recirculation in a fabric filter. This process enhances performance and reduces reactant consumption, ensuring compliance with stringent emission limits.

Principle
The system is flexible and removes acid gas components through neutralization with hydrated lime or equivalent reagents. Heavy metals and polyaromatic compounds are absorbed by activated carbon or lignite, and dust is removed by filtration.

Applications

• Suitable for use with hydrated lime or equivalent reagents.
• Operates within a flue gas temperature range of 130 – 400°C.
• Handles flow rates from 5,000 to 150,000 Nm3/h.
• Manages dust loads of less than 7 g/Nm3.
• Achieves high removal efficiency: over 99% for HCl and over 80% for SOx.

Process Description
Flue gas is cooled to about 140°C before entering the venturi reactor, where it contacts the reagent. Acid components, heavy metals, and volatile organic compounds are partially removed. The Sonair filter traps particles, forming a dust cake that completes the neutralization and absorption reactions. The dust cake is regularly cleaned and recycled back to the reactor, with excess product directed to a residue silo for disposal.

Features

• Designed to meet stringent emission limits.
• Low investment and maintenance costs.
• Minimal moving parts and no water consumption.
• Reduced reagent consumption through residue recirculation.
• High flexibility to handle pollutant peaks.

Conclusion
The Keppel Seghers’ Dry Scrubbing System is an efficient and flexible solution for flue gas cleaning, focusing on cost-effectiveness, ease of operation, and environmental compliance.