With the advancement of dry desulfurization technology, its significant advantages are driving it to replace wet desulfurization. Many desulfurization towers in the market, which have been in operation for years, are nearing their maintenance periods or service life due to corrosion and other issues. If these towers are to be replaced, the investment and operational costs would be less favorable compared to switching to the dry desulfurization process.  

Dry desulfurization employs high-efficiency calcium-based desulfurizing agents, which are strongly alkaline inorganic non-metallic powders. These agents offer unparalleled advantages in gas adsorption, reaction activity, fluidity, and reaction speed. Additionally, they adapt to a wide range of flue gas temperatures (0°C–430°C), require lower construction investment, produce lower carbon emissions, and generate by-products that are easy to recycle, making them highly promising for widespread application.  

The high-efficiency calcium-based desulfurizing agent produced by Shandong Vanda Environmental Technology Co., Ltd. has been extensively applied in industries such as lime kilns, coking, steel, smelting, chemicals, mineral processing, and building materials. It has demonstrated long-term effectiveness in complex flue gas conditions, achieving a desulfurization efficiency of over 97%.  

Drawbacks of Wet Desulfurization  

● Desulfurization wastewater causes secondary pollution, emits strong irritating odors, and requires hazardous waste treatment for sludge and wastewater.  

● Wet desulfurization consumes large amounts of water resources, with much of the water evaporating into steam. When cooled, this steam condenses, forming white plumes that contribute to visual pollution (haze). In areas with strict environmental regulations, additional "dewhitening" treatment is necessary.  

● The condensation of white plumes forms water droplets, leading to corrosion of surrounding equipment and deterioration of the working environment.  

● Wet desulfurization systems have high installed power requirements, resulting in elevated electricity costs and high operational expenses.  

● Desulfurization ponds and towers occupy large areas, involve complex equipment, and incur high maintenance costs.  

● Sludge removal from desulfurization ponds is labor-intensive, emits strong odors, and poses safety risks for workers.  

● Some regional governments have begun to phase out the use of wet desulfurization in certain industries.  

Advantages of Dry Desulfurization  

● No wastewater discharge, no sludge treatment, no odors, and no secondary pollution.  

● Both the desulfurizing agent and by-products are dry, preventing condensation, eliminating white plumes and corrosion, and requiring no water consumption. Ducts and chimneys do not need anti-corrosion measures.  

● Dry desulfurization systems have a compact footprint, feature refined equipment, and incur low maintenance costs.  

● Lower installed power requirements reduce electricity costs and operational expenses.  

● Automated intelligent control adjusts the dosage of the desulfurizing agent precisely based on sulfur dioxide concentration.  

● The entire desulfurization process is simple, with high equipment operation rates and ease of operation.  

● Dry desulfurization aligns with environmental trends and national policy advocacy.  

Upgrade and Retrofit  

The upgrade only requires the addition of a desulfurization island. The island's metering and feeding equipment precisely doses the desulfurizing agent into the flue based on sulfur dioxide concentration. The flue acts as the reactor, removing sulfur dioxide and generating desulfurization by-products. These by-products are collected by the existing bag filter and processed alongside dust. The resulting solid waste is easy to handle and can be repurposed in the building materials industry.