COMPLEX EFFECT OF WATER HARDNESS AND CORROSION INDEX ON THE HYDRAULIC EFFICIENCY OF CENTRIFUGAL PUMP UNITS: EXPERIMENTAL AND ANALYTICAL APPROACH

Abstract

<p>This&nbsp;article&nbsp;investigates&nbsp;the&nbsp;effect&nbsp;of&nbsp;increasing&nbsp;total&nbsp;water&nbsp;hardness&nbsp;and&nbsp;corrosion&nbsp;indices&nbsp;on&nbsp;the&nbsp;hydraulic&nbsp;efficiency&nbsp;of&nbsp;centrifugal&nbsp;pumping&nbsp;units&nbsp;using&nbsp;experimental&nbsp;and&nbsp;analytical&nbsp;methods.&nbsp;Using&nbsp;D,&nbsp;1D,&nbsp;K,&nbsp;KM,&nbsp;and&nbsp;NK&nbsp;pumps&nbsp;operated&nbsp;in&nbsp;regions&nbsp;of&nbsp;Uzbekistan&nbsp;with&nbsp;hard&nbsp;water&nbsp;as&nbsp;examples,&nbsp;the&nbsp;processes&nbsp;of&nbsp;carbonate&nbsp;deposit&nbsp;formation&nbsp;on&nbsp;the&nbsp;inner&nbsp;surfaces&nbsp;of&nbsp;the&nbsp;impellers,&nbsp;volute&nbsp;casings,&nbsp;and&nbsp;pipelines,&nbsp;the&nbsp;reduction&nbsp;of&nbsp;the&nbsp;flow&nbsp;cross-sectional&nbsp;area,&nbsp;and&nbsp;the&nbsp;increase&nbsp;in&nbsp;hydraulic&nbsp;resistance&nbsp;were&nbsp;analyzed&nbsp;under&nbsp;conditions&nbsp;of&nbsp;total&nbsp;water&nbsp;hardness&nbsp;ranging&nbsp;from&nbsp;8&nbsp;to&nbsp;32&nbsp;°dH,&nbsp;a&nbsp;Langelier&nbsp;Index&nbsp;ranging&nbsp;from&nbsp;0.7&nbsp;to&nbsp;2.6,&nbsp;and&nbsp;a&nbsp;Ryznar&nbsp;Index&nbsp;ranging&nbsp;from&nbsp;5.3&nbsp;to&nbsp;7.1.&nbsp;It&nbsp;was&nbsp;established&nbsp;that&nbsp;when&nbsp;the&nbsp;Langelier&nbsp;Index&nbsp;exceeds&nbsp;1.5,&nbsp;the&nbsp;service&nbsp;life&nbsp;of&nbsp;pumping&nbsp;units&nbsp;is&nbsp;reduced&nbsp;by&nbsp;42–56%,&nbsp;while&nbsp;the&nbsp;maintenance&nbsp;interval&nbsp;decreases&nbsp;by&nbsp;2.5–3&nbsp;times.&nbsp;The&nbsp;obtained&nbsp;results&nbsp;may&nbsp;serve&nbsp;as&nbsp;a&nbsp;scientific&nbsp;basis&nbsp;for&nbsp;developing&nbsp;practical&nbsp;recommendations&nbsp;on&nbsp;the&nbsp;design&nbsp;of&nbsp;pumping&nbsp;stations,&nbsp;the&nbsp;selection&nbsp;of&nbsp;water&nbsp;pre-</p><p>&nbsp;softening&nbsp;technologies,&nbsp;the&nbsp;optimization&nbsp;of&nbsp;chemical&nbsp;treatment&nbsp;regimes,&nbsp;andthe&nbsp;improvement&nbsp;of&nbsp;the&nbsp;energy&nbsp;efficiency&nbsp;of&nbsp;existing&nbsp;pumping&nbsp;units.</p>