Fig 4: Five day SO3 data sequence.
4. The data sequence contains five days of data, and is representative of normal operation at this specific installation. This plant has a threshold SO3 level fixed at 0.15 percent volume. The SO3 should not stay above this level. If it does, the plant’s operators have to adjust the furnace accordingly. In applications such as this, close attention to programming and calibration will help assure successful installations. Opsis is an ISO17025 accredited calibration laboratory.
If knowing accurate levels of SO2 and SO3 at various locations throughout the process can help optimize production, while not continuously adding to the cost of operations, then the investment in a system like this can be justified. For more information, please contact John Connell of CleanAir at (847) 654-4680 or jconnell@ cleanair.com. For international inquiries, please contact Carl Kamme of Opsis AB at +46 (0)46-72 25 00 or carl.kamme@opsis.se. q
TORONTO—As acid temperature rises, the corrosion rate of a 93-98 percent sulfuric acid tank increases rapidly, contaminating the acid and decreasing service life. Anodic protection is an economical solution that reduces iron pick-up and extends tank life by minimizing the corrosion rate. For a typical acid tank, an anodic protection system consists of cathode and reference electrode hardware installed through the tank roof (so it does not require tank entry) and an automatic potential controlled rectifier installed adjacent to the vessel. The installation is straightforward and can be done by a local contractor. Unlike expensive applied coatings the system can be installed on acid tanks which are in operation, reducing the need for costly shutdowns. Initially, direct current (DC) is applied to the vessel, moving the corrosion potential of the vessel from the high corrosion region to the passive region where
a tenacious film of oxide forms on the metal surface. After this initial passivation, nominally 5 percent of rated current is required to maintain the passive film. Corrosion Service Company Limited (CSCL) has over 60 years of experience applying Anotection® Anodic Protection systems for acid tanks and piping globally. Anotection® increases the life span of infrastructure and the quality of the acid with respect to iron content, an important criterion for acid purchasers. This makes Anotection® particularly beneficial in the manufacture, storage and transport of acids. Anotection® systems feature complete automatic system operation. Remote monitoring service is available at a low cost to ensure the system operation is optimal, with minimal maintenance requirements. For more information, contact Corrosion Service Co. Ltd. at (416) 630-2600 or e-mail acid@corrosionservice.com q
ENGINEERING TOMORROW’S CORROSION SOLUTIONS TODAY ™ SURFACE PROTECTION SYSTEMS KNIGHT-GARD™ Surface Protection Systems work in any area of the sulfuric and phosphoric acid industries. From coatings, membranes, laminates, paving, trench and wall linings, we offer a complete package of products to solve your surface protection problems. Our surface protection systems come in a variety of materials for superior performance in a wide range of chemical, thermal and mechanical conditions.
Secondary Containment Sump/Pump Boxes Trenches Storage Tanks Surface Protection
TURN KEY SOLUTION - COMPLETE CUSTOM SOURCE - SURFACE PROTECTION Koch Knight, LLC - PO Box 30070 - 5385 Orchard View Drive SE - East Canton, Ohio 44730 - Phone: +1(330) 488-1651 - Email: info@kochknight.com Sulfuric Acid Today • Spring/Summer 2013
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Maintain acid purity and control corrosion with anodic protection