Private-Public Innovation Project
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GRUNDFOS BIOBOOSTER PRIVATE-PUBLIC INNOVATION PROJECT WASTEWATER TREATMENT AT HERLEV HOSPITAL, DENMARK BACKGROUND AND PROJECT OBJECTIVES HOSPITAL WASTEWATER Herlev Hospital, located in the However, (BAT) the best available Project deliverables also include: are needed to improve the removal hazardous substances and patho- CONTAINS A COMPLEX Capital Region of Denmark, faces techniques (here specifically tech- - demonstrating that air emissions of pollutants. The test programme gens. Therefore risk assessments MIXTURE OF HAZARDOUS these wastewater challenges as nology that is both technically and can be treated for pathogens and includes the evaluation of robust- are crucial instruments to evaluate PHARMACEUTICALS, the Danish government wants to economically feasible to treat the odour. ness, energy consumption and total whether the treatment technolo- HARMFUL PATHOGENS ensure that hospital wastewater hospital wastewater) has not yet - demonstrating that the by-prod- economic performance under long- gies can remove all the important AND ANTIBIOTIC is handled according to the Envi- been defined and therefore the re- ucts can be disposed of in an en- term operating conditions. risks whilst at the same time not RESISTENT BACTERIA. ronmental Protection Act’s regu- quirements for any discharge per- vironmentally sound manner. create any unintended risks. DHI lations concerning the use of the mit cannot be specified at present. - Developing a control method to will carry out environmental and THE TEST PROGRAMME THESE CANNOT BE RE- Best Available Techniques (BAT). detect when GAC filters are satu- health risk assessments in relation MOVED BY CONVENTIONAL INCLUDES THE EVALUATION Their objectives are to seek a treat- The purpose of this project is to ad- rated in order to optimise replace- OF ROBUSTNESS, ENERGY to all emissions from the WWTP MEANS OF WASTEWATER ment solution for Herlev Hospi- dress the above objectives and has ment intervals. CONSUMPTION AND TOTAL which are comprised of water efflu- TREATMENT. HOWEVER, tal’s wastewater which will allow been organised as a private-public ECONOMIC PERFORMANCE ents, sludge and air emissions. The THEY POSE A THREAT TO the hospital to obtain a license to consortium. It will demonstrate Long term performance testing of UNDER LONG-TERM risk assessments include analysis PUBLIC HEALTH, THE operate either via a permit for dis- and document the treatment ca- technologies OPERATING CONDITIONS. for pharmaceuticals, disinfectants, ENVIRONMENT AND TO charge to public sewer works or via pabilities and economic conse- The full-scale plant will be perfor- detergents, pathogens – including PEOPLE WHOSE DAILY a permit for direct discharge to a quences of a full-scale wastewater mance tested through an intensive multi-resistant bacteria – as well as WORK BRINGS THEM IN local recipient (Kags Stream). This treatment plant (WWTP) treating monitoring and test programme. Environmental and health risk as- bio-tests to measure any genotoxic CLOSE CONTACT WITH will then allow the Capital Region the wastewater at the point of Tests of each part of the technol- sessments and endocrine effects on organisms THE WASTEWATER. of Denmark and Herlev Hospital to source as opposed to, for example, ogy will be used to evaluate exactly Hospital wastewater is charac- living in water. implement their solution in other a centralised solution. where in the process adjustments terised by a complex mixture of hospitals in the region. 2 3 Gain for the environment and economic gain for the hospital TIME SCHEDULE The treatment technologies used to remove phar- maceuticals and pathogens from the hospital’s 2012 Pre-project, collection of international experience, lab-scale tests wastewater result in high quality water which should be viewed as a resource which can be uti- Planning and establishment of the full scale pilot treatment plant 2013 lised. The ultimate aim of this project is to dis- Test period and reporting of interim results charge the treated water directly into the nearby 2014 stream (Kags Stream), which needs water through Final report due the summer period. Achieving this goal will also 2015 bring the hospital a very attractive payback time on their investment. This is due to significant sav- ings on their effluent discharges to public sewer and treatment works. At the same time, the improved effluent water quality opens up for the possibility to reuse the water as technical water (cooling water/boiler water) inside the hospital and/or for use as recrea- tional water as part of the architectural design of the hospital area. Knowledge gained so far Performed pilot/lab tests on wastewater from Her- lev Hospital and Rigshospitalet in Denmark as well as other projects in Europe focusing on the elimi- nation of pharmaceuticals have shown good treat- ment results using either ozone or activated car- bon. Test results have also indicated though that both ozone and activated carbon might be needed to fully eliminate the ecotoxicity of the treated ef- fluent, even though pharmaceuticals are below the limits of detection. Previous tests raise some uncertainty as to which technology or sequence of ozone and activated carbon will be optimal from a cost/performance point of view. Full flow treatment Previous studies in the Capital Region of Denmark have proven that it is very difficult to target spe- cific pharmaceutical-rich wastewater streams. Consumption of environmentally critical pharma- ceuticals is spread across hospital departments, patients move around to toilets located in differ- ent premises of the hospital, and departments are relocated over time. At Herlev Hospital all waste- water will therefore be treated in the WWTP to en- sure that no hazardous pharmaceuticals, harmful pathogens or antibiotic resistant bacteria will end up in the environment. 4 5 OpEN UP FOR DENMARK’S MOST ADVANCED WWTP This full-scale pilot wastewater treatment plant Featuring: (WWTP) will have a capacity that matches a small - Wastewater treated for pharamceuticals, harmful town with 2500 inhabitants. pathogens and antibiotic resistant bacteria, A glass front allows by-passers to get an inside look - Air emissions treated for pathogens and odour of what will become Denmark’s most advanced WWTP. 6 7 Combined buffer- and bioprocess tanks Post-treatment Air treatment ABOUT THE FULL SCALE PILOT In order to find the ideal way of eliminating pharma- All process related air emissions are treated using pho- ceuticals, the post-treatment has been divided into two toionisation, UV light and a catalyst before release in or- WASTEWATER TREATMENT PLANT parallel operating lines: Post-treatment line 1 and Post- der to eliminate pathogens and odours from the air; it treatment line 2. is therefore safe to install a wastewater treatment plant close to a hospital. Post-treatment line 1 Line 1 consists of Granular Activated Carbon, followed Disposal of debris and bio-sludge The pilot WWTP will have a capacity that matches a The MBR part by Ozone and/or H 0 . All debris from inlet screens and excess sludge from small town with 2500 inhabitants. The plant design is based around an MBR system 2 2 This skid is equipped with an option to add H O prior to the biological process are sent to incineration in order When completed it will be the most advanced WWTP (Membrane Biological Reactor) which consists of Ozone reaction tank 2 2 ozone injection which ensures the full transformation to completely eliminate any threats from these sources. in Denmark equipped with membrane bioreactors, biological process tanks followed by ultra-filtration of ozone into hydroxyl radicals. The latter oxidizes the As the bio-sludge contains pharmaceuticals both in the activated carbon and ozone technologies and will pro- membrane for the retention of biomass. The resultant pharmaceutical much faster and more effectively than microbes and in the water phase, the bio-sludge cannot vide a very high water quality similar to that of drink- particle and bacteria free water provides optimal con- molecular ozone. be dewatered after leaving the site as this will release ing water levels. ditions for the next post-treatment step and allows for pharmaceuticals into the environment again. To keep the adjustment of the biological treatment capacity to GAC tanks Finally the skid uses UV light to eliminate any residual the cost of transport and incineration to a minimum Plant definition match the hospital’s future requirements in the same ozone before discharge and as an extra safety barrier and improve handling, the bio-sludge is dewatered and Herlev Hospital will be expanded in terms of both ac- process tanks. against pathogens. dried on site by up to 90%, this dry matter is then stored tivities and buildings. Additional medical specialities in big bags which are transported directly to the incin- and an expansion of the on-site sterilisation centre The process tanks work as combined buffer and pro- Air blowers for bioprocess Post-treatment line 2 eration plant. will also be assembled at the hospital. The number of cess tanks. All biological processes take place inside Line 2 consists of Ozone followed by Granular Activated beds will increase from 595 beds to 825 beds and the the process tanks. The process tanks can be operated Carbon. This skid also has UV light as an extra safety number of people working at the hospital will increase with or without full removal of Nitrogen (using in- barrier against pathogens. from about 4000 people to about 6000 people. termittent aeration) and Phosphorous (through