Calcium-based fixed bed dry desulfurization process equipment

Introduction to Calcium-Based Fixed Bed Dry Desulfurization Process Equipment

Calcium-based fixed bed dry desulfurization process equipment is an efficient and environmentally friendly flue gas treatment technology widely used in industries such as steel, silicon, and coking. Below are the core features and application scenarios of this process equipment:
1. Process Principle
Desulfurization Reaction: Through the reaction of calcium hydroxide (Ca(OH)₂) with sulfur dioxide (SO₂) in the flue gas, calcium sulfate (CaSO₄) and water are generated. The reaction formula is:
SO₂ + 1/2 O₂ → SO₃
SO₃ + Ca(OH)₂ → CaSO₄ + H₂O.
Ammonia-Free Denitrification: Simultaneously removes nitrogen oxides (NOₓ), generating calcium nitrate (Ca(NO₃)₂), avoiding ammonia escape issues.

2. Equipment Structure
Fixed Bed Reactor: Utilizes axial or radial flow design, with flue gas and desulfurizing agent in countercurrent contact. The modular structure allows flexible adaptation to load changes.
Dust Suppression Function: The desulfurizing agent particle layer also serves a dust removal role, stabilizing outlet particulate matter below 5mg/m³.
Maintenance-Free Design: No need for additional operators; by-products (calcium sulfate, calcium nitrate) can be recycled and treated.
3. Technical Advantages
Low Cost: Lower initial investment and operating costs, reduced power consumption, and no need for additional fuel for heating.
Environmental Friendliness: No wastewater generation; by-products are solid waste, superior to the hazardous sodium salt waste from soda ash desulfurization and the hazardous waste issues of SCR catalysts.
Flexibility: Supports phased construction; future upgrades only require online filling of desulfurizing/denitrifying agents.
4. Application Cases
Steel Industry: Projects such as the rolling mill heating furnaces at Fujian Sansteel and a steel plant in Changzhou have achieved ultra-low emissions (particulate matter <5mg/m³).
Silicon Industry: Addresses the impact of high particulate matter in submerged arc furnace flue gas on desulfurization efficiency, avoiding contamination of microsilica quality.
Policy Support: Included in the "Catalog of Major Environmental Protection Technology Equipment Encouraged by the State (2023 Edition)".