Contents
7.2.1 Denitrification plants with separate sludge
243
7.2.2 Denitrification plants with combined sludge
243
7.2.3 Biofilters for denitrification
247
7.3. Design of denitrifying plants
248
7.3.1 C/Nratio
249
7.3.2 Stirring/ oxygen
253
7.3.3 Nitrogen gas in settling tanks and biofilters
254
7.3.4 Oxygen consumption
257
7.3.5 Alkalinity
258
7.3.6 Design of activated sludge plants with denitrification
258
7.3.7 Computerized process design
261
7.3.8 Design of biofilters for denitrification
265
7.4. Redox-zones in the biomass
268
8. Plants for Biological Phosphorus-Removal
273
8.1. Mass balances, biological phosphorus removal plants
with activated sludge
273
8.2. Plant types, biological phosphorus removal
276
8.2.1 Biological phosphorus removahW.itli
nitrification-denitrification and\an internal carbon source
276
8.2.2 Biological phosphorus removahwith nitrificationdenitrification and an external carbon source
278
8.2.3 Biological phosphorus removal with internally
produced easily degradable organic matter
279
8.2.4 Biological phosphorus removal without nitrificationdenitrification
279
8.3. Design of biological phosphorus removal
279
8.3.1 Easily degradable organic matter
279
8.3.2 Design of tanks for biological phosphorus removal
281
8.3.3 Optimization of plant operation; biological
phosphorus removal
283
9. Anaerobic Wastewater Treatment
285
9.1. Mass balances, anaerobic plants '
286
9.2. Plant types, anaerobic processes ,
289
9.2.1 Pretreatment of wastewater, anaerobic plants
289
9.2.2 Plants with suspended sludge
290
9.2.3 Anaerobic filter processes
293
9.2.4 Layout of an anaerobic treatment plant
295
9.3. Design of anaerobic plants
295
9.3.1 Design of plants with suspended sludge
296
9.3.2 Design of anaerobic filter plants
300
9.3.3 Gas production, anaerobic processes
302
9.3.4 Optimization, anaerobic plants
304
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