SOxFREE® Exhaust Gas Cleaning System

Advanced Solutions for Cleaner Marine Emissions

The SOxFREE® Exhaust Gas Cleaning System (EGCS), developed by Qingdao Sunrui, is designed to significantly reduce sulfur oxide emissions from marine diesel engines. Utilizing seawater or sodium hydroxide solutions, this system removes over 95% of sulfur oxides, ensuring compliance with IMO regulations. It maintains sulfur content below 0.5% outside Emission Control Areas (ECA) and under 0.1% within ECAs. Available in three configurations—open-loop, closed-loop, and hybrid—the SOxFREE® system offers versatile solutions to meet various operational needs. 

Open-Loop System

The open-loop system primarily includes a seawater pump, scrubber, flue gas analyzer, and water quality analyzer. It uses seawater as the desulfurizing agent:

• Desulfurization Process: Seawater absorbs sulfur dioxide, converting it into sulfite. Alkaline ions like bicarbonate and carbonate in the seawater neutralize the resulting hydrogen ions.
• Scrubber Design: The scrubber, available in U-type or I-type towers, features a titanium bottom for corrosion resistance. U-type towers can be packed or empty, while I-type towers are empty sprays. This design supports dry burning without additional exhaust gas bypass pipes or valves.

Closed-Loop System

The closed-loop system comprises a seawater pump, scrubber, flue gas analyzer, water quality analyzer, alkali supply unit, and water treatment unit. It uses sodium hydroxide to maintain pH levels:

• Desulfurization Process: Sodium hydroxide is added to the circulating water tank to balance pH during the spray process, ensuring effective desulfurization. The cleaned flue gas is then released, and the washing water is recirculated. Part of the washing water undergoes treatment and is stored, while separated sludge is collected in a sludge tank.
• Scrubber Design: Similar to the open-loop system, the scrubber in the closed-loop configuration is independently developed by Qingdao Sunrui, featuring U-type or I-type towers with titanium bottoms for durability and resistance to corrosion.