COMPLIANCE INFO_1972-1989 - Laserfiche WebLink

Home Browse Search

Y. 2. Washing Place the catalyst in a sieve and flush with a solvent or detergent and water. Thoroughly rinse in clean water. Dry with hot air at a temper- ature less than 3000F. Sudden application of higher temperature will cause entrapped liquid within the catalyst to vaporize with sufficient pressure to crack some of the catalyst. Do not wash or dry the catalyst when the atmos- pheric temperature is at freezing or sub-freezing levels since this would cause expansion of the liquid entrapped in the catalyst. Drying with compressed air is not recommended as there is a temperature drop in the air as it leaves the nozzle. Some carbon particles become ingrained deeper in a catalyst substrate due to washing and, along with any detergent, will remain with the catalyst when dried. For this reason, do not use a detergent with phosphate, a catalyst poison. 3. Screening After cleaning, the catalyst should be screened on a small mesh screen such as Number 8 U.S. and any "fines" falling through the screen should be discarded. Cleaning may not restore the catalyst in all cases, depending on prior history of catalyst use. If cleaning does not restore catalyst function, replace the catalyst. SELECTION PROCEDURE The first step in sizing a MAXIM catalytic silencer is to know the exhaust flow rate in lbs/min. If the engine exhaust gas flow rate is not in lbs/min, convert to this flow rate by using the appropriate conversion factor. Next scan the column listing the maximum flow rate for catalytic silencers until you reach a flow rate greater than the exhaust gas flow rate. Read horizontally for the appropriate size designation. The last step is to calculate the exhaust gas pressure drop across the catalytic silencer. Use the formula: AP = 4H)2 (TO) (2.096 X 10-8) A where W = Exhaust gas flow rate in lbs/min 2 A = Inlet connection area of catalytic silencer in ft (Table II) TO = Exhaust gas temperature in degrees Rankin K = Configuration coefficient C/24