废水处理教程p

1、WASTE WATER. compositionSuspended solids (SS) Organic matter (BOD/COD)Phosphorous (P)Nitrogen (N)WASTE WATER. critical constituentsKnowing these constituents - waste water impact on the environment - proper way of treating waste water- waste water history . so lets find out. Settleable substance on

2、the bottomColor from suspended solidsOxygen consumption caused by organic constituents, which bacteria and micro-organism decompose. WASTE WATER. sewage impact on recipientPhosphorus and nitrogen causes an increase in algae production (eutrophic). Then decomposing gives a secondary oxygen consumptio

3、n in the waterToxic effect on biological life. Toxic constituents such as heavy metals, cyanides and phenolsBiological changes in the recipient caused by warm water from cooling system.Hard decomposable material increasesWASTE WATER. sewage impact on recipientWASTE WATER. sewage impact on recipientA

4、t small pollutant load the effects are generally eliminated by the natural self-cleaning (treatment) in recipient.At hard pollutant loading sewer damage can occur in the recipient Possible effects1 g of Nitrogen (N) totally assimilated and used for new bio-mass1 700 g algae-mass equal to 115 g algae

5、 DS equals 138 g COD1 g of Phosphorous (P) totally assimilated and used for new bio-mass16 g bio-mass equal to 20 g CODWASTE WATER . PROPERTIESORGANICINORGANICUN-SOLVEDDIS-SOLVED1/3unsolved(1/3colloidal)1/3dissolved1/3colloidal90%dissolved10%unsolvedcomposition1 person emits per day:NitrogenPhosphor

6、ousOrganic materialSuspended solids10-14 g N2,5-3,5 g P50-80 g BOD570-90 g SSWASTE WATER. PROPERTIESPHYSICAL- Solved- Unsolved- Other :- odor - colour - temp.CHEMICAL- Organic- InorganicThe dry (105 oC)weight of constituents 0,45 mm (filter)In aeration tank expressed asMixed Liquer Suspended SolidsM

7、LSSWaste Water properties, physicalSUSPENDED SOLIDS (SS)The organic (600 oC)part of SS 0,45 mm (filter)In aeration tank expressed asMixed Liquor Volatile Suspended SolidsMLVSSWaste Water properties, physicalVOLATILE SUSPENDED SOLIDS (VSS)The dry (110 oC)weight of constituentsincluding saltsWaste Wat

8、er properties, physicalDRY SOLIDS (DS)The organic (600 oC)weight of constituentsWaste Water properties, physicalVOLATILE DRY SOLIDS (VDS)Waste Water properties, ORGANIC MATTER (BOD)Biochemical Oxygen Demand (BOD)Biological degradable material in the water.Micro-organism consuming oxygenAnalyzed in 5

9、 or 7 or 20 daysBOD5 BOD7/1,1550100150200250mg O2/l510152025daysWaste Water properties, ORGANIC MATTER (BOD)Waste Water propertiesORGANIC MATTER (COD)Chemical Oxygen DemandOxidation with Mn or Crconsuming oxygenWaste Water properties . COD/BOD ratioNon-treated wasteCOD/BOD 2-3100 mg O2/l (BOD7) 200-

10、300 mg O2/l (COD)Waste Water properties, chemicalINORGANIC MATTERINORGANICNitrogen (N), Phosphorous (P),Oxygen, Metals (Fe, Mn, Al) etc.90% dissolved constituents (salts)Waste Water properties, chemical INORGANIC MATTERNITROGEN (N)(Organic nitrogen)Inorganic nitrogenammonia-nitrogen NH+4 -Nnitrate-nitrogen NO-3 -Nnitrite-nitrogen NO-2 -NWaste Water properties, chemicalNormal content in waste waterCalculation of waste water flow to STPQdim= Qs/Ts + Qi/Ti+Qd/24Qdim = design waste water flow m3/hQs = sewage from households m3/d Qi = industrial sewage m3/dQ