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Wet Gas Condenser

Chemetics® Wet Gas Condenser (WGC) provides significant advantages in terms of reliability and maintenance over Star Coolers and Cooling Towers for greenfield and brownfield applications.

Key benefits. • Lower operating cost • Robust and reliable • Longer life span • Almost maintenance free • Ease of cleaning • Easy to retrofit and replacement • Elimination of hazardous material of construction such as lead

About Chemetics Sustaining our world for generations to come through technological and environmental innovation, Worley delivers Comprimo® sulphur and Chemetics® sulphuric acid solutions around the globe with a focus on site reliability, plant economics and workforce development. Over the past 50 years, Chemetics’ full life cycle solutions and equipment have enabled more than 800 plants achieve higher capacities and availability, lower costs of operation, reduced emissions and greater safety. Leveraging our R&D lab and custom-built fabrication facility in Canada, global transportation and logistics management capabilities, specialized project teams and worldwide network of trusted suppliers, we deliver optimal solutions and equipment for your sulphuric acid facility, from greenfield projects to maintenance and turnarounds.

Client Solutions Wet Gas Condenser Features and Benefits: In the Sulphuric Acid Gas Cleaning Plant hot dirty gasses are cleaned and conditioned before they are sent to the contact process. The basic steps required are wet quenching, gas cooling and acid mist removal. For the gas cooling service, historically this has been done with lead lined ‘star’ coolers, or by indirect cooling in packed or venturi towers. The WGC is a vertical shell and tube heat exchanger where the process gas passes down through the tubes and cooling water on the shell side. As the gas is cooled, water and some contaminants condense on the tube walls and collect in the bottom of the vessel. A small amount of condensed liquid is pumped to the top of the WGC as a spray to minimise accumulation of debris on the top tubesheet and in the tubes. The WGC is typically arranged with several units in parallel followed by Wet Electrostatic Precipitators (WESP). This provides redundancy and the ability to remove a WGC and WESP pair for cleaning or maintenance with a minimal reduction in overall capacity. In services with high contaminant loads, a secondary set of WGCs and WESPs installed in series might be required.

Ease of Retrofit/Replacement • The WGC can be designed as a bolt-in replacement for a lead ‘star’ cooler, matching duct, cooling water and support connections. Typically the WGC provides lower pressure drop or increased cooling in the same volume as the original lead ‘star’ cooler. Chemetics specializes in the design, supply and installation of replacement condensers in existing plants. The flexibility of the design enables most exchangers to be replaced with only minimum modifications to ducting and foundations. Chemetics’ WGCs provides the advantage of minimal maintenance and the assurance of continuous operation.

The process gas entering the WGC from the quench venturi scrubber is very corrosive due to weak acid and contaminants such as fluorides. The material selection of the WGC is critical to the reliability of the equipment. Chemetics has extensive experience in material selection for Gas Cleaning Plant service, including in-house metallurgists and material testing facilities. Typically high nickel alloys such as C-276 or 6 moly type stainless steels are used in contact with the process gasses, with the precise selection custom selected for your specific plant conditions. Chemetics’ WGCs are fully fabricated at Chemetics’ Pickering fabrication facility thereby guaranteeing the product and workmanship to be of the highest quality. Advantages of WGC over lead ‘star’ coolers:

Wet gas condenser general arrangement

Health, Safety and Environment (HSE) • Eliminates lead, which is an environmental and health hazard and can be difficult to find qualified workers for repairs. Ease of Maintenance and Cleaning • Smooth tubes reduce the amount of fouling that builds up inside. • Top vestibule sprays allows continuous cleaning of tubesheet and tubes. • Lead tubes are soft and easily damaged during cleaning and maintenance, which leads to leaks and eventual collapse of the supporting structures. • Alloy construction allows rapid pressure water lance cleaning. Longer Lifespan • All WGCs have strength welded tube to tubesheet joints to provide a positive seal between the process and cooling gas streams. • The strong alloy tubes can tolerate normal cooling water pressures. • WGCs have been installed in this service for over 30 years without repair or replacement. The expected lifespan of a WGC is typically double to triple that of ‘star’ coolers.

Top tubesheet of a wet gas condenser after 25 years in service