Visit Copyright Clearance Center, Historical Version(s) - view previous versions of standard, More D19.03 Standards The three common kinds of silica are soluble, colloidal and particulate. The documents listed below are referenced within the subject standard but are not provided as part of the standard. See our, CORROSION COUPONS & CORROSION PROBES - PROS…, KNOWLEDGE BASED CONTROL AND LEAK DETECTION…. Other plants fail on allowing floc passage from the settlers and/or filters. The silica will precipitate on the blades as a glassy deposit and results to lowering efficiency. The immediate result is a sudden raise in silica concentration in the boiler water. It can contribute to the formation of colloidal iron and colloidal manganese. Both dissolved and total … As a result, it can cause problems with deposits being formed as well as scaling. For more information, see our Cookie Policy. Non-reactive silica thus includes polymerized (aka polymeric), colloidal and insoluble silicates (aka suspended or granular silica). Standard References. Nonreactive silica is usually measured indirectly, i.e. Often, colloidal silica is also defined as “anything” that will be retained by a 0.22 micron filter. Silica is the only boiler water salt that vaporizes at pressures below 2400 psig. Owing to its volatility, … In the internal treatment for silica, … Silica causes etching, scratching, and spotting on glassware and other fixtures. Boiler scale is caused by impurities being precipitated out of the water directly on heat transfer surfaces or by suspended matter in water settling out on the metal and becoming hard and adherent. Common … For water treatment, silica can foul reverse osmosis (RO) membranes under some conditions. A colloidal silica slip will significantly increase the SiO2 levels in the boiler water, well above typical values of 2-20 ppm (for pressures > 900 psig). Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard. Due to the extremely tight filtration of the R.O. Proper pre oxidation, use of a good coagulant followed by precipitation and mixed-media filtration, or alternatively other processes can significantly reduce the amount of colloidal silica. We and third parties such as our customers, partners, and service providers use cookies and similar technologies ("cookies") to provide and secure our Services, to understand and improve their performance, and to serve relevant ads (including job ads) on and off LinkedIn. CASE 3 –COLLOIDAL SILICA REMOVAL Customer Jindal Power Ltd, Raigarh, Chattisgarh Raw Water Source Surface water Problem •Colloidal silica in raw water created problems on turbine in power plant Flow m3/hr 100 x 3 Streams Inlet Colloidal Silica … This colloidal silica is not ionised and, therefore, is not properly eliminated by traditional systems used in the treatment of boiler water (clarification + ion exchange) (see chapter treatment and conditioning of … You can change your cookie choices and withdraw your consent in your settings at any time. Proper maintenance of water chemistry helps in minimizing corrosion, deposition, and scaling problems in boiler and turbine and prevents costly shutdown and material replacement. After the colloid is destroyed, this silica which firstly was “hidden” suddenly appears. Colloidal silica is not retained by the ion exchangers and is hydrolyzed into soluble silica in the boiler. 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