Water & Wastewater Asia September/October 2019

More documents

Recommendations

Info

20 | FROM THE GROUND New perspective on sources with ozone treatment of wastewater In the Netherlands, drinking water company PWN and water board HHNK set up a project to investigate if it would be technically and financially feasible to use ozone with ceramic microfiltration to tackle micro-pollutants for both water and wastewater, and to explore the reuse possibilities for purified wastewater. One of the main reasons for the project was the increasing volume of medicine residues, hormones, nanoplastics and pesticides in wastewater. Medicine residue was a key issue, but with an aging population the use of medication was increasing and it was not possible to prohibit its use. Already 140 tons of medicine and 30 tons of X-ray contrast media were found to end up in surface water via the sewer, which was a problem on a national level. Warmer temperatures and a “dehydration” effect caused by climate change also meant that the concentration of medicine residue in the water was to sharply increase. “If we can remove the medicine residues from wastewater before it is discharged to surface water, we are protecting our sources,” said PWNT Technologist Bram Martijn. “Sustainable and long-term solutions always have been key drivers for PWN in both source protection and technology implementation.” said PWN and PWNT’s CEO Joke Cuperus. “The CeraMac ® technology provided by PWNT applying METAWATER ceramic microfiltration membranes will play an important role in these long-term re-use investigations for PWN.” Water & Wastewater Asia • September / October 2019
FROM THE GROUND | 21 STRATEGIC LOCATION In 2017, PWNT’s technologies involving ozonation and ceramic microfiltration were included in the HHNK purification process in a small-scale facility. The location for this pilot was strategically chosen. The sewage treatment plant had been defined as a “hotspot”, indicating that the concentration of medicine residues in the wastewater was relatively high. In addition, the sewage treatment plant discharged its effluent to lake IJssel, the most important drinking water source for PWN, where PWN in Andijk pre-treats the surface water for eventual drinking water and the steel and paper industry in the immediate vicinity. OZONE AS AN OXIDANT It soon became clear that drinking water technologies could also work on treating wastewater. Said Ronald Koolen, Project Manager at HHNK, “Based on pioneering work in Germany and Switzerland, it was known that ozonation and treatment with active carbon are currently the most effective techniques for breaking down microcontaminants and especially drug residues in effluent. We chose ozonation because this strong oxidant gives a higher yield and does not create any residual current. But there are also disadvantages, and the most important side effect that we had to control was the formation of bromate, a substance that is a suspected carcinogenic.” OPTIMAL MIX Now PWN and HHNK have better insights into how they can prevent bromate formation. Said Martijn, “In collaboration with Wetsus (Bram Delfos), the University of New Hampshire (Daniel Farley) and expert Dr Joop Kruithof, research has been conducted on the effects of different ozone dosages in the last two years, to find out how many substances would be broken down with what amounts of ozone, and how much bromate would be formed. The expectation was that adding hydrogen peroxide would slow bromate formation. The conclusion was that ozone in combination with H2O2 can be dosed in such a way that 16 common drug residues are broken down by more than 80 per cent, while bromate formation remains very limited. These are encouraging results that help to further develop this application and, in this way, keep our sources cleaner.” INNOVATION IN LABORATORIES In the meantime, the project has improved measurement and analysis techniques for medicine residue in water. “Laboratories used different measurement and analysis techniques for different drug residues,” explained Martijn. “The costs of the various measurement and analysis techniques were very high and it is therefore not efficient for the laboratories either. That is why the Dutch Ministry of Infrastructure and Water has, partially thanks to this project, made half a million Euros available to laboratories in the water chain to invest in innovations that overcome this problem. This has led to the development of a measurement method with which the removal of medicines from the sewage treatment plant effluent and any follow-up treatments can be unambiguously determined, with the additional advantage that the samples can be processed in the analyser without further processing. That also brings time and cost savings.” CLOSING THE WATER CHAIN It is clear that project “Ge(o)zond” – a combination of ozone and the Dutch word for health – is getting a lot of attention. The Dutch Association of Water Boards awarded the project with the prestigious ‘Water Innovation Award’. According to the jury, ‘The three elements of the innovation are: an optimal combination of available techniques, the direct application of the purified water for high-quality use and the innovative monitoring.’ With this, important steps are taken towards source control and the closing of the water chain.” Said Koolen, “Until recently, the water boards were mainly thinking about the reuse of substances that we extract from the water. Now, we also look at the water itself, the product of both PWN and HHNK. CONTRIBUTION TO THE CIRCULAR ECONOMY The project’s partners are investigating possibilities for high-quality reuse of the purified wastewater. Martijn added, “PWN is already producing industrial water from the lake IJssel. What if that water quality could be directly supplied in the future in the form of further purified effluent from the sewage treatment plant? That would give us extra capacity to continue to meet the increasing demand for drinking water from the lake IJssel.” NEW PERSPECTIVE ON PURIFICATION PROCESSES The reuse of effluent in many densely populated areas with water scarcity has been a common practice for a long time. Martijn said, “What makes this project special and innovative in my opinion is that we look at the reuse of water from a different perspective. Instead of using all possible technologies to get as much as possible out of the water, we reverse the process. First, we ask the question: what do we want to reuse the water for? We then look for the technologies to get the water quality required for that use. EVERYONE’S INTEREST “We are just at the beginning,” said Koolen. “The preparations for a larger-scale installation with a capacity of 300-1200 cubic metres per hour for the conversion of medicine residues are at an advanced stage. The HHNK board received the plans for this with great enthusiasm. The idea is that HHNK will buy the installation this year and that it will be built in 2020 in collaboration with PWN. We have shared interests, with the emphasis for PWN on source protection, and for HHNK on clean and healthy water. And that is ultimately in everyone’s interest.” WWA Water & Wastewater Asia • September / October 2019
Page 1: Water & Wastewater Asia INCORPORATI
Page 4 and 5: WATER & WASTEWATER ASIA CONTENTS SE
Page 6 and 7: 4 | NEWS PT. Grundfos Pompa inaugur
Page 8 and 9: NSL OilChem Waste Management has of
Page 10 and 11: 8 | MARKET REPORT Looking beyond th
Page 12 and 13: 10 | MARKET REPORT operators Vodafo
Page 14 and 15: 12 | MYANMAR WATER PORTAL regularly
Page 16 and 17: 14 | IN PERSON Silvertex: Sometimes
Page 18 and 19: 16 | FROM THE GROUND Advanced radar
Page 20 and 21: 18 | FROM THE GROUND reduce its hig
Page 24 and 25: Continuous Microbial Monitoring: on
Page 26 and 27: 24 | INSIGHT Efficient sludge thick
Page 28 and 29: 26 | INSIGHT A wastewater plant in
Page 30 and 31: 28 | INSIGHT The dock “thinks”
Page 32 and 33: 30 | INSIGHT and passive sections.
Page 34 and 35: 32 | INSIGHT Communicative trends i
Page 36 and 37: 34 | INSIGHT Balmoral Tanks expands
Page 38 and 39: 36 | INSIGHT Improving water access
Page 40 and 41: 38 | INSIGHT Using the vortex layer
Page 42 and 43: 40 | OPINION Business raising its a
Page 44 and 45: 42 | OPINION Atmospheric Water Gene
Page 46 and 47: 40 TH SINGAPORE WATER INDUSTRY NITE
Page 48 and 49: IndoWater 2019, Singapore Pavilion
Page 50 and 51: Digitising 48 | COMPANY PROFILE wat
Page 52 and 53: 50 | COMPANY PROFILE From Water- Wi
Page 54 and 55: E Reaching new heights with Borouge
Page 56 and 57: 54 | TECH ROUND UP The Kuraray team
Page 58 and 59: 56 | TECH ROUND UP Tsurumi single-p
Page 60: 58 | TECH ROUND UP EMERSON introduc
Page 64 and 65: The IWA Water and Development Congr
Page 66: ADVERTISERS INDEX WATER & WASTEWATE

Water & Wastewater Asia September/October 2019

Create successful ePaper yourself

Delete template?

Save as template?