OVERVIEW OF THE FUTURE TRENDS IN WASTEWATER TREATMENT Prof. Hallvard Ødegaard Department of Hydraulic and Environmental Engineering Norwegian University of Science and Technology (NTNU) N-7491 Trondheim – NORWAY hallvard.odegaard@bygg.ntnu.no http://www.ntnu.no/~halo/ NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

DEVELOPMENT OF WASTEWATER MANAGEMENT NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

Prof. Hallvard Ødegaard THE DEVELOPMENT OF WATER WITHDRAWAL IN THE WORLD WATER USE CHARACTERISTICS NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

MANY REGIONS IN DEVELOPING COUNTRIES ARE WITHOUT WASTEWATER TREATMENT NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

Prof. Hallvard Ødegaard THE MEGACITIES CHALLENGE Many megacities do not treat their wastewater or they treat by primary treatment only Mexico City Many of these cities are situated by the ocean They have little space for treatment plants They are in need for a affordable secondary treatment concept NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

EUTROPHICATION AND LACK OF NUTRIENT REMOVAL IN MANY DEVELOPED COUNTRIES There is still a huge market for P- and N-removal in many developed countries: UK Eastern Europe US Japan Australia NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

Prof. Hallvard Ødegaard REUSE OF THE TREATED WATER In most regions of the world the use of water has been : Supply driven Price of water low In the future water use in many regions will be : Demand driven Price of water will increase Extensive treatment of wastewater cost effective NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

RESOURCES IN WASTEWATER WILL HAVE TO BE UTILISED Agricultural reuse - irrigation Urban reuse Industrial reuse Potable water reuse 1. The water itself 2. The constituents in the wastewater 3. The heat of the wastewater Nutrients (C,N,P) Carbon for energy production (biogas, biofuel) Metals for reuse (Al, Fe) Energy for heating/cooling NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

SELECTION OF FUTURE TREATMENT PROCESSES MUST BE BASED ON WASTEWATER CHARACTERISTICS RECEIVING WATER CHARACTERISTICS TREATMENT EFFICIENCY COST SLUDGE PRODUCTION POTENTIAL USE OF UTILISING THE RESOURCES IN THE WASTEWATER NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

Prof. Hallvard Ødegaard FACTORS THAT HAVE TO BE TAKEN INTO ACCOUNT TREATMENT EFFICIENCY Focus today : Oxygen consuming matter (BOD/COD and NH4-N) and nutrients (P and N) Focus in the future : Microbial contaminants (helminth eggs, parasitic protozoa, bacteria,virus ) Micropollutants (heavy metals as well as organic MPs) COST Cost is very much linked to space requirement – especially in the big cities Compact treatment alternatives will be asked for in many cases Biofilm systems may replace activated sludge systems High rate separation techniques may replace settling tanks SLUDGE PRODUCTION Disposal of sludge : Increasingly higher portion of total cost Methods are looked for that minimize sludge production and that utilize the resources of the sludge NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

Prof. Hallvard Ødegaard NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

SUSTAINABLE WASTEWATER TREATMENT STRATEGIES TOWARDS SUSTAINABLE WASTEWATER TREATMENT The role of particles NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

SIZE OF ORGANIC PARTICLES IN WASTEWATER NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

CLASSIFICATION OF ORGANIC MATTER IN WASTEWATER ACCORDING TO SIZE After Balmat (1957), Heukelekian and Balmat (1959), Richert and Hunter (1971) NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

Prof. Hallvard Ødegaard EXAMPLES FROM SCANDINAVIAN WWT PLANTS Fraction of suspended COD and BOD NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

Prof. Hallvard Ødegaard EXAMPLES FROM SCANDINAVIAN WWT PLANTS Fraction of N and P on suspended form Generally : Plants with high fraction of soluble COD has low fraction of particulate N and P assimilation in sewers NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

THE ASSOCIATION OF OTHER POLLUTANTS TO PARTICLES Heavy metals (example from a wastewater treatment plant) Virus : 0,01 - 0,1 µm 60-100% adsorbed to particles Bacteria and 0,1 - 10 µm Parasitic protozoa : 2 - 60 µm (Cryptospiridium: 4-6 µm) Helminth eggs : 20 - 80 µm (Ascaris, Taenia) Organic micropollutants : Very high affinity to particles 70 - 95 % of PCB and PAH associated to particles NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

SUMMARY ON CONSEQUENCE OF WASTEWATER CHARACTERISTICS A very substantial reduction of all pollutants can very efficiently be removed by removing particles and colloids The rate at which proceeding biological processes will perform, will increase by removal of particles and colloids IT IS VERY LOGICAL TO ENHANCE PRIMARY TREATMENT for instance by pre-coagulation or by coarse filtration NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

MY BASIC WASTEWATER TREATMENT PHILOSOPHY : Take out the particles first Then deal with the solubles Enhanced primary Removal of solubles Make use of the concentrate Carbon source Organic concentrate Biogas Utilize the resources from the concentrate Nutrients NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

Prof. Hallvard Ødegaard WHAT IS ENHANCED PRIMARY TREATMENT ? TODAY Enhanced primary settling Cogulant aided Primary precipitation TOMORROW Coarse primary filtration Coagulant aided VERY SOON AFTER TOMORROW Membrane filtration NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

AVERAGE TREATMENT RESULTS IN NORWEGIAN PRIMARY PRECIPITATION PLANTS NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

TRADITIONAL PRIMARY PRECIPITATION DOWNSIDE OF TRADITIONAL PRIMARY PRECIPITATION LARGE SLUDGE PRODUCTION SP = SSin - SSout + Kprec * D SP = sludge production (g SS/m3) Kprec = sludge production coeff. (g SS/g Me)(Fe~4, Al~6) D = dose ofmetal coagulant (g Me/m3) NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

Prof. Hallvard Ødegaard SLUDGE PRODUCTION CAN BE REDUCED BY USE OF POLYMER NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

Prof. Hallvard Ødegaard ENHANCED PRIMARY TREATMENT BY COARSE MEDIA FILTRATION Pilot plant Plastic filter media L: light –polyethylene, 0,95 g/cm3 H: Heavy – PVC, 1,45 g/cm3 NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

ENHANCED PRIMARY TREATMENT Comparison of single media filters: K1L and K2L filters NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

FAVORABLE COMBINATIONS OF TREATMENT SYSTEMS NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

Prof. Hallvard Ødegaard COMPACT SECONDARY TREATMENT ? You have taken out must of the particulate BOD and a relatively small amount of low MW, easily biodegradable, soluble BOD is left High-rate sedimentation Flotation Sand filtration Membrane filtration Residence time: 15–30 min 10-15 min NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

Prof. Hallvard Ødegaard THE PRINCIPLE OF THE MOVING BED REACTOR Aerobic reactor Anaerobic/anoxic reactor NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

THE KALDNES MOVING BED BIOFILM PROCESS Aerated MBBR Carrier under water NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard

SOLUBLE COD REMOVAL RATE VERSUS SOLUBLE COD LOADING RATE Period 1 and 2 Period 3 NTNU - Norwegian University of Science and Technology Dep. Hydraulic and Environmental Engineering Prof. Hallvard Ødegaard