濾料

Filtermedia濾層內(nèi)雜質(zhì)分布規(guī)律

ImpurityDistributionPatterninFilterLayer由于反沖洗的水力篩選作用，造成沿濾層深度方向?yàn)V料粒徑逐漸增大,

Duetothehydraulicscreeningeffectofbackwashing,theparticlesizeofthefiltermediagraduallyincreasesalongthedepthofthefilterlayer;表層濾料粒徑小，孔隙率最小，吸附表面積最大；

Theparticlesizeofthesurfacefiltermediaissmall,theporosityisminimum,andtheadsorptionsurfaceareaismaximum;下層濾料粒徑大，孔隙率大，吸附表面積小。

Thelowerfiltermediahaslargeparticlesize,largeporosityandsmalladsorptionsurfacearea.細(xì)

Fine粗

Coarse濾層含污量（g/cm2）

Filterlayerdirtcontent(g/cm2)單層濾料

Singlelayerfiltermedia石英砂

Quartzsand濾料深度

Filterdepth(cm)過濾剛開始,濾層比較干凈，孔隙率較大，孔隙流速小，水力沖刷作用小，大量雜質(zhì)被表層5-10cm厚度的濾料所截留，少量雜質(zhì)因粘附不牢而下移，并被下層濾料所截留。

Atthebeginningoffiltration,thefilterlayerisrelativelyclean,withlargeporosity,smallporevelocityandsmallhydraulicscouringeffect.Alargenumberofimpuritiesareretainedbythefiltermedia5-10cmthickonthesurfacelayer,andasmallnumberofimpuritiesmovedownduetopooradhesionandareretainedbythelowerfiltermedia.濾層含污量（g/cm2）

Filterlayerdirtcontent(g/cm2)單層濾料

Singlelayerfiltermedia石英砂

Quartzsand濾料深度

Filterdepth(cm)濾料

Filtermedia濾層內(nèi)雜質(zhì)分布規(guī)律

ImpurityDistributionPatterninFilterLayer濾料

Filtermedia濾層內(nèi)雜質(zhì)分布規(guī)律

ImpurityDistributionPatterninFilterLayer過濾剛開始,濾層比較干凈，孔隙率較大，孔隙流速小，水力沖刷作用小，大量雜質(zhì)被表層5-10cm厚度的濾料所截留，少量雜質(zhì)因粘附不牢而下移，并被下層濾料所截留。

Atthebeginningoffiltration,thefilterlayerisrelativelyclean,withlargeporosity,smallporevelocityandsmallhydraulicscouringeffect.Alargenumberofimpuritiesareretainedbythefiltermedia5-10cmthickonthesurfacelayer,andasmallnumberofimpuritiesmovedownduetopooradhesionandareretainedbythelowerfiltermedia.濾層含污量（g/cm2）

Filterlayerdirtcontent(g/cm2)單層濾料

Singlelayerfiltermedia石英砂

Quartzsand濾料深度

Filterdepth(cm)濾料

Filtermedia濾層內(nèi)雜質(zhì)分布規(guī)律

ImpurityDistributionPatterninFilterLayer濾層含污能力Filterlayerdirtholdingcapacity單位體積濾層中的平均含污量稱為“濾層含污能力”，單位g/cm3或kg/m3

Theaveragedirtcontentinafilterlayerperunitvolumeiscalledthe"dirtholdingcapacityofthefilter"(ing/cm3orkg/m3)單層濾料由水分篩分,濾料上細(xì)下粗,使得下層濾料含污能力不能充分發(fā)揮。

Thesingle-layerfiltermediaissievedbymoisture,andthefiltermediaisfineintheupperlayerandcoarseinthelowerlayer,sothatthedirtholdingcapacityofthelowerfiltermediacannotbefullyrealized.濾層含污量（g/cm2）

Filterlayerdirtcontent(g/cm2)單層濾料

Singlelayerfiltermedia石英砂

Quartzsand濾料深度

Filterdepth(cm)上層：密度小、粒徑大的輕質(zhì)濾料

Upperlayer:lightfiltermediawithsmalldensityandlargeparticlesize下層：密度大、粒徑小的重質(zhì)濾料

Lowerlayer:heavyfiltermediawithlargedensityandsmallparticlesize充分發(fā)揮各層濾料的截污能力，提高濾池的過濾效率。

Fullyrealizetheretainingcapacityofeachlayeroffiltermediaandimprovethefiltrationefficiencyofthefilter.濾料

Filtermedia濾層內(nèi)雜質(zhì)分布規(guī)律

ImpurityDistributionPatterninFilterLayer下層粗濾料

Lowercoarsefilter過濾水頭一定，濾速急劇減??；

Thefiltrationheadisconstantandthefiltrationratedecreasessharply;表層細(xì)濾料

Surfacefine

filtermedia濾速一定，水頭損失達(dá)到限值；

Thefiltrationrateisconstantandtheheadlossreachesthelimit;泥膜破裂，水質(zhì)惡化。

Themudfilmrupturesandthewaterqualitydeteriorates.濾層中雜質(zhì)的分布情況：

Distributionofimpuritiesinthefilterlayer:出現(xiàn)泥膜的結(jié)果：

Consequencesincaseofmudfilm:濾料

Filtermedia濾層內(nèi)雜質(zhì)分布規(guī)律

ImpurityDistributionPatterninFilterLayer濾層截污量：kg/m3

Retainingcapacityoffilterlayer:kg/m3濾層含污能力：一個(gè)過濾周期內(nèi)，平均值

Dirtholdingcapacityoffilterlayer:averagevaluewithinonefilterrun影響雜質(zhì)分布的因素：

Factorsaffectingimpuritydistribution:進(jìn)水水質(zhì)

Quality水溫

Temperature濾料粒徑

Particlesize形狀和級配

Shapeandgradation濾速

Filtering

rate凝聚顆粒強(qiáng)度

Strength衡量濾料層截留雜質(zhì)能力的指標(biāo)：

Indicatorstomeasuretheimpuritiesretainingcapacityofthefiltermedialayer:濾料

Filtermedia濾層內(nèi)雜質(zhì)分布規(guī)律

ImpurityDistributionPatterninFilterLayer濾速

Filtrationrate濾速越大，水流的沖刷作用也大，雜質(zhì)在濾層中的穿透深度越大，雜質(zhì)在整個(gè)濾層中的分布越均勻。

Thegreaterthefiltrationrateis,thegreaterthescouringeffectofwaterflowis,thegreaterthepenetrationdepthofimpuritiesinthefilterlayeris,andthemoreuniformthedistributionofimpuritiesinthewholefilterlayeris.濾料粒徑及級配的影響

Influenceofparticlesizeandgradationoffiltermedia濾料組成的影響

Influenceofmediacomposition濾料粒徑越大,粒徑越均勻,孔隙率越大,雜質(zhì)的穿透深度增加，水頭損失增加緩慢，延長工作周期且能提高截污。

Thelargertheparticlesizeofthefiltermediais,themoreuniformtheparticlesizeis,thelargertheporosityis,thegreaterthepenetrationdepthofimpuritiesis,thelowertheheadlossgrowthis,thelongertheworkingperiodisandthebettertheretainingcapacityis.濾層組成的改變，改變了單層級配濾料層中雜質(zhì)的分布狀況，提高了濾層含污能力,降低了濾層中水頭損失的增長速率。

Thechangeofthecompositionofthefilterlayerwillchangethedistributionofimpuritiesinthesingle-layergradedfiltermedialayer,improvethedirtholdingcapacityofthefilterlayerandreducesthegrowthrateofheadlossinthefilterlayer.濾料

Filtermedia濾池過濾效率提高的途徑

MeanstoImproveFiltrationEfficiencyofFilter盡量使雜質(zhì)在濾層中均勻分布，采用“反粒度”過濾方式。

Impuritiesshallbeevenlydistributedinthefilterlayerasfaraspossible,andthe"reversegrain"filtrationmodeshallbeadopted.提高濾層含污能力的根本途徑：

Thebasicsolutiontoimprovethedirtholdingcapacityofthefilterlayer:雙層濾料

Double-layer三層濾料

Three-layer均質(zhì)濾料

Homogeneous石英砂

Quartzsand石英砂

Quartzsand無煙煤

Anthraciticcoal無煙煤