Advanced technologies for treating water, domestic and industrial wastewater. Prof. Hadas Mamane Water-Tech Laboratory Tel-Aviv University

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1 Advanced technologies for treating water, domestic and industrial wastewater Prof. Hadas Mamane Water-Tech Laboratory Tel-Aviv University

2 The Importance of Water Life on earth would be impossible without water All living organisms contain 70% water drinking, cooking, washing, agriculture, transportation, manufacturing, mining, energy production, waste disposal 2014 John Wiley & Sons, Inc. All rights reserved. By 2025, more than 1/3 of humans will live in areas with inadequate supply of fresh water for drinking and irrigation

3 Water Pollution in Developing Countries 1.4 billion people in the world do not have access to safe drinking water 2.9 billion do not have access to sanitation systems (1/3 of world population) 250 million cases of water-related illness each year 5 million or more result in death 1.8 million from diarrheal illnesses alone a year.

4 Global trends Worldwide population growth Global water resource distribution Use of chemicals 4

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6 Need for sustainable water use euse 3 s Water reuse - Nonpotable water that is highly treated and used for approved purposes other than drinking water, to reduce potable water consumption (California Code of Regulations) 6

7 Results in The need - Increasing need for water reuse (treated wastewater) The source - Municipal WW a major source The risk - Emerging contaminants in treated wastewater (effluent) as pharmaceuticals, pesticides, personal care products Therefore-there is an increasing interest in advanced wastewater treatment 7

8 8 WATER USE

9 Israeli perspective Water Resources and Water Demand Average total natural enrichment billion m 3 /annum Water demand more than 2 billion m 3 /annum Current potable water demand ~ 1.2 billion m 3 /annum Forecast for potable water demand: 2020 ~ 1.7 billion m 3 /annum 2030 ~ 1.95 billion m 3 /annum 2040 ~ 2.2 billion m 3 /annum 2050 ~ 2.45 billion m 3 /annum Data by Israel Water Authority

10 Standard precipitation index Simulated and expected droughts Drought magnetite, intensity and duration are expected to increase in the future LAST droughts period NEXT droughts period Data by Israel Water Authority

11 The Water Revolution in Israel New Era In 2016, 75%-80% of the drinking water in Israel will be supplied by desalination Drinking water in Israel North Lake Kinneret הערה: עקב מצבה העגום של הכנרת המספרים יורדים והשנה יהיה מלמ"ק כולל אספקת 50 מלמ"ק לירדן מצמח Main water resources (Mm 3 ) in the national system in Coastal aquifers Main water resources (Mm 3 ) in the national system in Seawater desalination Mountain aquifers 11 Data: Israel water authority, Mekorot Average total natural enrichment billion m 3 /annum Water demand more than 2 billion m 3 /annum 2050 ~ 2.45 billion m 3 /annum The annual natural rain we get meets barely 75% of the demand and this deficit exists WW reuse is one of the leading solutions for the growing water scarcity in the world.

12 NATIONAL CONSUMPTION: AGRICULTURAL SECTOR (48%) 400 (38%) (26%) 900 (67%) 144 (14%) 100 (7%) If effluent were not used in agriculture, desalinated water production would be required (a more costly alternative) to supply the agricultural sector s needs.

13 Wastewater reuse in Israel Israel is an expert in the treatment, reclamation and utilization of wastewater for agricultural irrigation (over 85%) More than 85% of wastewater in Israel is reused after secondary and tertiary treatment for irrigation

14 Wastewater Reuse Situation in Israel Wastewater in Israel: domestic (93%), industrial (6%) and cow-shed wastewater (<1%) 508 million cubic meters / year (in 2012). About 94% (468 million cubic meters) are treated by mechanical-biological treatment facilities and stabilization ponds The rest is disposed to primary facilities, streams and others (no discharge of raw 14 wastewater into the sea).

15 In Israel Industrial Wastewater (WW) Raw domestic / industrial WW Treated by mechanicalbiological treatment facilities and stabilization ponds Treated by primary facilities or not-treated and used for irrigation WW disposed not treated to streams and the environment other Secondary effluent to the environment (nature, streams, surface water) Secondary effluent for irrigation tertiary treatment as infiltration by soil aquifer treatment (SAT) Tertiary effluent for unrestricted irrigation 15

16 Purple pipe Purple pipes used for reclaimed water distribution systems 16

17 Wastewater The production of waste from human activities is unavoidable. A significant part of this waste will end up as wastewater. Wastewater is the liquid or water-carried wastes removed from residences, institutions, commercial and industrial establishment (possibly together with groundwater, surface water and storm water). 19

18 Wastewater

19 Untreated wastewater Untreated wastewater may contain pathogenic microorganisms (from human intestinal tract), nutrients (simulate growth of aquatic plants) and toxic compounds (mutagenic, carcinogenic). Therefore it is important to remove wastewater from its sources of generation, followed by treatment to produce effluent, reuse or dispersal into the environment. 21

20 Wastewater treatment Necessary to allow disposal of human and industrial effluents without the risk to human health and to the natural environment. In some developed countries, mainly where the agriculture plays an important economy factor, wastewater has been changed from a burden to a resource, in term of water quantity. The whole process depends on collection, treatment and reuse infrastructures. 22

21 Treatments for reuse of effluent Chemical coagulation, biological or chemical nutrient removal, filtration, and disinfection Activated carbon, reverse osmosis, advanced oxidation processes, soil aquifer treatment Treatment technology to achieve the desirable water quality for reuse (EPA, 2012) Urban, Agriculture, Environmental, industrial, groundwater recharge

22 Types of reuse appropriate for increasing levels of treatment Primary Secondary Filtration and Disinfection Advanced Sedimentation Biological Chemical Activated carbon, oxidation and coagulation, reverse osmosis, disinfection biological or advanced oxidation chemical nutrient processes, soil aquifer removal, filtration, treatment, etc. and disinfection

23 Primary treatment Designed to remove gross, suspended and floating solids from raw sewage. Includes screening to trap solid objects and sedimentation by gravity to remove suspended solids. Can reduce the B.O.D of the incoming wastewater by 20-30% and the total suspended solids by 50-60%.

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25 Secondary treatment Removes the dissolved organic matter. Achieved by microbes consuming the organic matter as food, and converting it to carbon dioxide, water, and energy for their own growth and reproduction. The biological process is then followed secondary sedimentation to remove more of the suspended solids. Secondary treatment can reduce about 85% of the suspended solids and B.O.D. Secondary treatment technologies include the basic activated sludge process, the variants of pond and constructed wetland systems.

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28 Normal floc Zooglea ramifera Filamentous floc Pin floc 31

29 Amoebae - Indicator of low Sludge Age in Aeration Basin Filamentous Bacteria Rotifer Nematode - (Worm) - Indicator of high Sludge Age in Aeration Basin

30 Tertiary treatment Provides a final treatment stage to raise the effluent quality to the desired level. Tertiary treatment can remove more than 99% of all the impurities from sewage, producing high quality effluents.

31 Tertiary treatment Filtration + disinfection Granular filtration - is the passage of effluent through a porous medium to remove suspended solids. Most commonly used filter media are natural silica sand, garnet sand, crushed anthracite coal, and granular activated carbon. Pressure driven micro and ultrafiltration membranes - relies on a liquid being forced through a membrane with a high surface area. Membrane filtration is designed to remove bacteria, viruses, pathogens, metals, and suspended solids.

32 Specific gravity: Silica sand, 2.55 to 2.65 Anthracite coal, 1.5 to 1.75 Garnet, 4.0 to 4.3 Ilmenite, 4.5

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34 Advanced treatment Activated carbon- An adsorbent material that provides a surface on which ions or molecules in the liquid or gaseous phase can concentrate. Used to remove natural organic compounds, taste and odor compounds, and synthetic organic chemicals from source water. Advanced membrane treatment technologies based on ultra-filtration (UF) and reverse osmosis (RO) yield effluent of suitable quality for unrestricted irrigation.

35 Israeli regulation/barriers 10/10/10 for TSS/BOD/E. Coli Effluents disinfection Extra treatment Secondary treatment (stabilization ponds) Number of required barriers Secondary treatment (activated sludge) Vegetables eaten nonboiled required required forbidden 2 0 Vegetables eaten boiled required forbidden 2 0 Vegetables with shells (Melon, peas) required required forbidden 2 0 Citrus required Deciduous fruit trees (Apple, plum, pear, required peach) Tropical fruits required Tertiary advanced treatment Notes: Extra treatment refers to one of the following treatments: Filtration, disinfection, reside in closed reservoir for a period of 30 days, mix of effluents with freshwater, with ratio of 90/10 (90% fresh water and 10% effluents). Number of required barriers refers to implementation of barriers out of several options, in order to separate the crop and the effluents, such as distance from applied effluent to the fruit/vegetable 38

36 Reuse Urban Reuse Agricultural Reuse Environmental Reuse Industrial Reuse Unrestricted Restricted Food Crops Groundwater Recharge - No potable Reuse Processed Food Crops and Non-food Crops The use of reclaimed water for no potable applications in municipal settings where public access is not restricted The use of reclaimed water for no potable applications in municipal settings where public access is controlled or restricted by physical or institutional barriers, such as fencing, advisory signage, or temporal access restriction The use of reclaimed water to irrigate food crops that are intended for human consumption The use of reclaimed water to irrigate crops that are either processed before human consumption or not consumed by humans The use of reclaimed water to create, enhance, sustain, or augment water bodies including wetlands, aquatic habitats, or stream flow The use of reclaimed water in industrial applications and facilities, power production, and extraction of fossil fuels The use of reclaimed water to recharge aquifers that are not used as a potable water 39 source

37 Irrigation with untreated wastewater Unfortunately, irrigation of crops (both food and nonfood) with untreated wastewater is widely practiced in many parts of the developing world with accompanying adverse public health outcomes. Therefore, in developing countries, it is advised to adopt the lowest possible level of treatment, not only from the point of view of cost but also due to difficulties in operating complex systems reliably. In many locations it will be better to design the reuse system to accept a low-grade of effluent rather than to rely on advanced treatment processes producing treated effluents which continuously meets high quality standard.

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39 Recycled water issues-advanced treatment Urban wastewater treatment is not designed to break down drugs, pesticides, residues of personal care products Using reclaimed water for irrigation is a path to the entry of these chemicals into drinking water

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41 Problem Worldwide

42 Regulation of trace organic compounds (TOrC) in WWTP effluent-case study Switzerland 100 out of 700 WWTP must be equipped with ozone or powdered activated carbon absorption during next 20 years Based on polluters-pays principle (federal law) A set of indictor compounds will be proposed for 80% removal no discharge limit conc. 45

43 Indictor compounds - Switzerland Sulfamethoxazole (antibiotic) Diclofenac (pain-killer) Mecoprop (herbicide) Benzotriazole (corrosion inhibitor) Carbamazepine (anti-apileptic) 46

44 Innovative technology to treat contaminants in water using reactive species as free radicals

45 WHY ADVANCED OXIDATION PROCESS (AOP)? Species Oxidation Potential (V) Flourine Hydroxyl Radical Hydroxyl Radical Atomic Oxygen Ozone Extremely reactive Hydrogen Peroxide Short lived Permanganate Unselective Hypobromous Acid Chlorine Dioxide Chlorine Very low steady-state concentration Hypochlorous [10-12 to 10 Acid -13 M]

46 WHY OZONE BASED AOP? Electrophilic oxidant (2.07 V) Direct reaction: Selectively reacts with compounds containing electronrich moieties Indirect reaction: Non selective hydroxyl radical ( OH) Formed from reaction of ozone with natural organic matter Parameters affecting ozonation Dissolved organic carbon (DOC) Nitrite Advantages: Efficiently remove TrOCs Increase the effluent dissolved oxygen (DO) conc. Increase the biodegradability of dissolved organic matter

47 Ozone for water reuse Widely used for drinking water, but recently used for reclaiming wastewater Best available technology for reducing trace organic compounds Also improves aesthetics, enhances biodegradebility, increases UVT, disinfects water, saturates water with oxygen Ozone + Biofiltration is an effective broad spectrum treatment option for high quality recycled water

48 Different ozone configurations

49 In Israel Israel is a world leader in the treatment, reclamation and utilization of wastewater for agricultural irrigation (over 85%)

50 1. Reclaimed water 4. Biofuels Free radicals 2. Hospital WW 3. Solar disinfection