Wasser- und Abwassertechnologien

• domestic effluent including black water (toilet water) and grey water (washing/sink water)
• water from commercial establishments and institutions
• industrial effluent
• storm water and other urban run-off

• depends on the origin of waste water
• Sum parameters for similar substances are defined and analyzed in one method for simplified characterization
• Biological effect parameters charaterize the toxicity for different endpoints (organisms, types of effect)

• Physical parameters: Temperature, flow rate, total dissolved solids (TDS), total suspended solids (TSS), turbidity etc.
• Organoleptic parameters: Taste, odour, etc. 
• General chemical parameters: pH, dissolved oxygen (DO), nitrogen, phosphorous etc.
• Organic chemical parameters:Biochemical oxygen demand (BOD), total organic carbon (TOC), absorbable organic halogens (AOX) etc.
• Microbiological parameters: Bacteria count, viruses, protozoae, algae
• Biological effect-parameters: Toxicity on bacteria, daphnia, fish etc

Concrete corrosion cause by acids, sulfates and sludge settling

Toxic effect on bacteria

• Mostly connected to high pollutant concentrations and limited biological degradability 
• Bacterial toxicity: e.g. antibiotics, disinfectants, acids, bases, preservatives and heavy metals (toxicity depends on concentration)
• Very sensitive: nitrification step in waste water treatment plants (WWTP) due 
  to inhibition of nitrifying bacteria
• Toxic effect on bacteria is described as dilution factor

Eutrophication

• Main reason: elevated concentrations of N- and P- compounds which are 
  limiting growth factors in many water bodies
• Eutrophication refers particularly to the increased growth of algae, which 
  causes depletion of oxygen

Fish polulation

• Acute fish toxic substances, e.g. ammonium 
• Substances, which destroy the food chain of fishes, so-called „daphnia 
  toxic“ substances
• „Persistent“ (not used in the metabolism) substances which accumulate in 
  the food chain and can cause long-term damages

Aquatic ecosystems/ Biodiversity

•  Acute or chronic toxic effects on individual or several species of the ecosystems
• An effect on the most sensitive species can destroy the ecological balance, which also influences less sensitive species

• physical: sedimentation, membrane processes, filtration, flotation
• physico-chemical: precipitation/flocculation, adsorption, ion exchange
• thermal: stripping/destillation, extraction, concentration by evaporation
• chemical: incineration, wet oxidation
• biological: aerobic, anaerobic

Advanced waste water treatment options 

• oxidative processes: ozonation
• membrane processes: reverse osmosis
• biotechnological processes: enzymatic processes
• adsorption: activated carbon

• Poor biological degradability: High residence times (15 h instead of 3-4 h)
• Higher raw COD: High energy consumption (energy efficient oxygen supply required); Aeration by injection, tower biology
• Odor problem (Housing and exhaust air treatment required)
• Toxic peaks possible (Monitoring of toxicity, huge buffer tanks) 
• Poor sedimentation of sludge (post-treatment by flotation)
• Sludge is not disposable (incineration necessary)
• typically: huge tank volume, high flexibility of operation 

Pesticieds, dyes, adhesives/paintings, plastics, textile fibers, soaps/detergents, metallic compounds, fertilizer, mineral oil and basic chemicals

Industrial waste water

Munixipal waste water -> quality of used water alsmost same as before using

• most effective and advanced stage of operation methods which indicate the practical suitability of particular techniques to prevent or reduce emissions
• Techniques: Both the technology used and the way in which the installation is designed, built, maintained, operated and decommissioned
• Available: implementation in relevant industrial sector feasible under economically and technically viable 
  conditions
• Best: most effective in achieving a high level of protection of the environment as a whole

BAT (Best Available Techniques) reference documents

• an exchange of information between Member States, the industries concerned, non-governmetal organisations (Art. 17)
• draw up, review and, where necessary, update BAT reference documents

• Federal Water Act (WHG)
  • general priciples of water management
  • permission of water uses
  • transposition of European legislation
  • wastewater treatment according to "state of the art"
• Water Protection Ordinance (Abwasserverordnung)
  • discharge limits for wastewater from different sources (Annexes)
  • monitoring requirements
• Wast Water Charges Act (Abwasserabgabengesetz)
  • financial incentive (polluter-pays-principle)
  • definition of "Pollution/Noxiousness Units" in kg of pollutants
  • collected charges should be used for water protection measures

• Noise: production, transport
• Waste: hazardous waste, residues
• Soil: heavy metal, toxic compounds of various chemical classes, PAH/CAH
• Air: dust, vapur, gases, SO2,NOX,VOC, greenhouse gases, CO2, Dioxins/Furanes
• Water: O2 depelting substances, heavy metals, persistent or toxic compunds of various chemical classes, heat

• Collection and treatment of wastewater
• Definition of minimum effluent quality with regard to: suspended solids, organic material (BOD, COD), nutrients (N, P)
• in dependency on: size / capacity of treatment plant; sensitivity of effluent receiving water
• “Treated wastewater shall be reused whenever appropriate”

• expanding the scope of water protection to all waters, surface waters and groundwater
• achieving "good status" for all waters by a set deadline 
• water management based on river basins
• "combined approach" of emission limit values and quality standards
• getting the prices right - full cost recovery
• getting the citizen involved more closely, public participation
• streamlining legislation

• Densitiy difference: sedimentation, centrifugation
• Adhesion of solids or gases on surface: flotation, deep bed filtration
• Retention on the filter surface by steric hindrance: surface filtration
• Dewatering by filters (filter press: surface filtration)

Total suspended solids, mg/l, the concentration of insoluble material in water or waste water

Total dissilved solids, mg/l, concentration of alll materials present in solution (survives filtration through a filter with 0.45müm pores)

Mixed liquor suspended solids, mg/l,

• suspended solids concentration on the mixed liquor in an activated dludge plant
• consists mostly of microorganisms and non-biodegradable suspended matter

Total organic carbon, mg/l as C, measure of the concentration of carbon derived from organic matter in water or waste water

Dissolved organic carbnon, mg/l,

Quality from diffuse sources, mainly agriculture 
 Hydromorphological, mainly from hydropower, navigation, agriculture, flood protection, urban development 

Lamellae separator

• high rate of clarification
• not appliacable to water with too much salt
• increased area for separation by a stack of inclined parallel plates
• inclination ca 60°

Centrifuge

• contact of the particle with the collector
• adhesion of the particle on the collector

• Barrier effect (Interception)
• sedimentation
• diffusion (Brownian motion)

1. Reverse osmosis: 0.001-0.0025μm, 20-200bar
2. Nanofiltration: 0.0006-0.007μm, 50-50bar
3. Ultrafiltraiton: 0.0004-0.14μm, 0.3-10bar
4. Microfiltration:0.06-20μm, 0.2-4bar
5. Particle Filtration: 5-100μm, 0.1-9bar

1. Reverse osmisis: monovalent ions, moleculse (water still goes through)
2. Nanofiltration: dissolved, org. substances, divalent ions
3. Ultrafiltration: viruses, colloids, macromolecules
4. Microfiltration: Partiicles, algae, protozoa, bacteria

• Irreversible cake layer: adsorbtion, compaction, precipitation
• Pore blocking: particle diameter
• Inner pore adsorption: permeable substances with affinity to membrane material
• Biofouling: MO in film consisting of EPS

External membrane separation

Integrated membrane separation