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    MINISTRY OF EDUCATION AND TRAINING Do Thi Minh Hanh DEVELOPMENT OF EVALUATION CRITERIA AND TECHNO-ECONOMIC CRITERIA TO ENSURE SUSTAINABLE OPERATION OF URBAN WASTEWATER TREATMENT PLANT Major: Environmental Technology, Water and Wastewater Treatment Code: 9520320-2 SUMMARY OF DOCTORAL DISSERTATION Hanoi, 2019     The study is completed at Supervisor 1: Ass.Prof.Dr Tran Duc Ha Supervisor 2: Dr Pham Tuan Hung Opponent 1: Ass.Prof.Dr Nguyen Hong Tien Opponent 2: Dr Le Van Long Opponent 3: Ass.Prof.Dr Do Khac Uan The Dissertation shall be defensed prior to the Dissertation Evaluation Committee (DEC) met at National University of Civil Engineering At .o’clock dated / / Further study may be investigated at library of National University of Civil Engineering   BACKGROUND Rationale Vietnam is characterized by theEast Asia’s 6th highest urban population [25] Fast urbanization speed in Vietnam is recorded with forecast on additional one million of new urban residents per year As of December 2018, Vietnam was the home of 819 cities, including: special cities namely Hanoi and Ho Chi Minh City, 19 cities of Grade I, 26 cities of grade II, 46 cities of grade III, 83 cities of grade IV and 645 cities of grade V By 2020, urban population shall hit approximately 44 million persons, accounting for 45% of urban population nationwide By 2025, 1,000 cities shall be available including 17 cities of grade I to special grade, 20 cities of grade II, 81 cities of grade III, 122 cities of grade IV and the remaining of city grade V[30] Meanwhile, the scope of water drainage and cleaning system service is relatively restricted due to disqualified physical and technical facilities both in terms of quantity and quality New drainage culvert system only satisfies 50-60% and 30-40% demand of population in major cities and small and medium cities, respectively The constructed wastewater treatment plants (WWTPs) are not abundant and ineffectively operated; hence, the treated urban wastewater volume under the environmental standards is not significantly recorded Vietnam Water Supply and Sewage Association (2019) revealed that, 37/63 localities were supported with WWTPs and localities were provided with concentrated domestic WWTPs [16] However, most of WWTPswere recorded with operation of less than 50% of designed capacity Event some WWTPs which have been constructed were not fully provided with wastewater for treatment One of root causes is that the difficulties in selecting wastewater technology and connection are faced by the concentrated wastewater drainage and treatment projects [11] Currently, wastewater revenue is generated by applying a fee percent against on all water consumers in accordance with the Decree No 154/2016/ND-CP or drainage service charge under the Decree No 80/2014/ND-CP The Decree No 154/2016/ND-CP on environmental protection fee specifies that the maximum Environmental protection fee for waste water must 10% of clean   water price that the drainage system management and operation demand cannot be successfully satisfied Drainage service charge under the Decree No 80/2014/ND-CP has been applied by some cities to mobilize the contribution from service users, reducing the pressure on the State budget Drainage service charge applied for the households is higher than the environmental fee and varied within the range of VND 1,000 – VND 2,600 [34] Although the drainage service charge is high, it is still remarkably lower than that of wastewater treatment price Actual operating costs must be funded by the local budget as Operation and Maintenance (O&M) costs cannot be covered by wastewater collection fees In fact, expenditure for wastewater system O&M is mainly relied on annual expenditure funded by the Provincial/Municipal People's Committee through the Department of Finance and allocated to the Department of Construction Revenue of Water Supply Company is originated from the water consumers Such revenue is held by the municipal or provincial authorities to redistribute to the wastewater enterprises in accordance with the approved annual budget In urban areas of Vietnam, there are only 46 WWTPs (as of the end of 2019) but many of them are not stable and efficient for many different reasons (although most them were just built during recent 10 years) Studies and assessments of this situation are very limited and incomplete Therefore, it is necessary to set up criteria to evaluate the sustainable operation of those plants According to the evaluation criteria and facilitate the feasible solutions to ensure WWTPs’ sustainable operation, the techno-economic criteria must be setup Bac Ninh City'sWWTP is developed from KfW (Germany) loan sources and has been put into operation since 2013 Upon years of operation, its great contribution on wastewater treatment and improvement of Bac Ninh water environment has been made In order to ensure the reliability and applicability, collected data on Bac Ninh WWTP management and operation is evaluated in accordance with the proposed criteria and techno-economic indicators Objectives   -   Design evaluation criteria for sustainable development of urban WWTPs -   Set up techno-economic criteria for sustainable development of urban WWTPs -   Apply the evaluation criteria and techno-economic criteria to ensure the sustainable development of Bac Ninh WWTP Subjects and scope of the research -   Subjects of the research: Management, operation and maintenance of urban WWTPs -   Scope of research: Urban WWTPs in Vietnam Scientific basis of the thesis: Through theoretical research on the sustainability of WWTP; collection and analysis of data, consultation with experts on the operation of the WWTPs to propose the criteria for evaluating the sustainable operation of the WWTPs Based on the criteria and the importance of each of these criteria, formulate the economictechnicalindicators to ensure the sustainable operation of the WWTPs Having theeconomic-technical indicators to help the operators to find out solutions to ensure the sustainable operation of WWTPs is the practical meaning of the thesis Research methodology According to the objectives, following research methodologies have been applied: -   Survey and collection of data and documents on technoeconomic criteria when investment project is prepared and management and operation of available urban WWTPs in Vietnam; -   Analysis and evaluation of techno-economic criteria of urban WWTPs; -   Development of questionnaire and construction of experts and technicians in urban wastewater treatment fields; -   Application of Analytic Hierarchy Process (AHP) method in combination with expert consultation to analyze the evaluation criteria and develop the techno-economic criteria to ensure sustainable operation of urban WWTPs In order to successfully fulfill the research objectives, the concerned contents and methods are summarized in Figure 0.1   General study on urban wastewater and sustainable operation of urban WWTPs (1)   Wastewater treatment capacity and efficiency (2)   Appropriateness of wastewater treatment technology with local conditions (3)   O&M costs (4)   Operating conditions of works and equipment (5)   Safety and environmental friendliness (6)   Adaptability with adverse impacts of climate changes and input factor changes Technology criteria group: - Wastewater capacity and mode - Wastewater treatment performance O&M criteria group: -Appropriateness with local context -Adaptability with climate change - Safety and environmental friendliness Legislation and management criteria group: -Operation management mechanism of WWTP operator - Management Financial criteria group: - Water drainage service charge -Income of WWTPs -O&M cost savings Data collection, literature review and analysis and evaluation Selection of proper evaluation criteria groups for urban WWTPs’ sustainability Quantitative analysis and evaluation in combination with expert consultation Determine weights and priorities of evaluation criteria groups for urban WWTPs’ sustainability Analyze by AHP in combination with expert consultation (supported by Expert Choice 11 Software) Design the technoeconomic criteria groups to ensure sustainable operation of urban WWTPs Analyze by AHP (supported by Expert Choice 11 Software) Discuss the main findings and propose the solutions on enhancing the sustainable operation of urban WWTPs Evaluate and adjust the main findings by data collected at BacNinh City’s WWTP Figure 0.1 Summary of research contents and method applied herein New implications -   Design evaluation criteria for sustainable development of urban WWTPs in Vietnam; -   Set up techno-economic criteria for sustainable development of urban WWTPs in Vietnam; -   Apply AHP method in combination with expert consultation to propose and determine weights of sustainability evaluation criteria in operation of WWTPs -   Propose the possible solutions for sustainable operation of Bac Ninh City’s WWTP in accordance with the techno-economic criteria Structure In addition to preface, conclusions, recommendations, appendix and list of publications, the study comprises of chapters: Chapter 1: Overview (40 pages) Chapter 2: Scientific basis and research methodology (30 pages) Chapter 3: Development of evaluation criteria for sustainable development of urban WWTPs in Vietnam (55 pages)   CHAPTER 1: OVERVIEW 1.1   Characteristics of urban wastewater and operation of concentrated urban wastewater treatment plants 1.1.1   Components and properties of urban wastewater Urban wastewater refers to wastewater originated from cities, mixed with domestic and production wastewater from industrial activities and services in the city and runoff Vietnam urban wastewater is characterized by 67-85% [2] of domestic wastewater Domestic wastewater volume in developing countries is estimated to be equal to 80% of water volume provided in the regions with normal development level and 90% of sharply developed areas [9] 1.1.2   Urban drainage and treatment in concentrated urban wastewater treatment plants urban drainage models are currently available, concretely: Concentrated wastewater treatment drainage; distributed wastewater treatment and drainage and onsite wastewater treatment 1.2   Evaluation of existing condition of urban WWTPs in Vietnam 1.2.1   Existing condition of urban WWTPs in Vietnam Number of constructed wastewater treatment plants (WWTPs) is not abundant and ineffective; hence, the treated urban wastewater volume under the environmental standards is not significantly recorded Vietnam Water Supply and Sewage Association, 2018, revealed that only 41 urban WWTPs are put into operation with total capacity of approximately 950,000 m3/day and 28 other WWTPs are being constructed However, most of WWTPs are recorded with operation of less than 50% of designed capacity Event some WWTPs which have been constructed are not provided with wastewater for treatment 1.2.2   Evaluation of operating performance of available WWTPs a) WWTPs’ business performance Concentrated wastewater treatment and drainage projects are faced with a myriad of difficulties in technology selection, works design and construction quality, appraisal procedures, household connection percent, financial affairs, operating capacity, local monitoring and control, environment monitoring during the project performance, etc With low input organic concentration, the urban WWTPs should be   applied with proper technologies at lower cost, facilitating the future scalability if the wastewater characteristics or input wastewater flow rate is improved Energy savings or efficiency, natural resource salvage from waste sludge or post-treatment wastewater reuse are not significantly focused and prioritized b) Efficiency of waste sludge and odor treatment Some projects only focus on wastewater treatment, rather than waste sludge and odor treatment The sludge treatment technologies, mainly including dehydration and waste sludge drying, are not stable Sludge treatment is not proper, resulting in bad odor in the area and entire plant 1.3   Root causes for unsustainable operation of urban WWTPs 1.3.1   Legislative causes a   Legal documents Water resource protection is specified in the Law on Environmental Protection, Law on Water Resources Legal implementation guidelines include: The Decree No 80/2014/ND-CP on wastewater drainage and treatment and the Decree No 25/2013/ND-CP on environmental protection fee for wastewater However, overlap and conflicts are still found among such legal documents, especially water drainage and environmental protection service charges Currently, the codes on urban wastewater discharging to surface water are still unavailable That is why the parameter values in QCVN 40:2011/BTNMT - National Technical Regulation on Industrial Wastewater or QCVN 14:2008/BTNMT - National Technical Regulation on domestic wastewater (applied for small scale subjects not through concentrated drainage system that is directly discharged into the external receiving environment) are applied as the hygiene conditions to discharge the urban wastewater to the receipt source b   Mechanisms and policies of management, investment and operation of drainage system and WWTPs Implementation of drainage-related mechanisms and policies is found with some restrictions as follows: Delay implementation, confused application and shortcomings due to restrictions in human resources as well as capacity and qualifications of officials from local regulators;improper concern on drainage, urban and industrial park wastewater treatment found in many local authorities 1.3.2   Management of assets and human resources   a Asset management and operation of drainage system and urban wastewater treatment Owners of wastewater treatment assets and operation management units have been specified in the Decree No 80/2014/ND-CP concerning the investment activities, management, operation and supply of drainage, wastewater collection and treatment services in areas However, Project Management Units (PMUs) has been still established in the drainage management enterprises b Human resources The world cutting-edge technologies in drainage and wastewater treatment have been approached and applied in Vietnam; however, the concerned in-depth training centers are unavailable The training institutions are not fully provided with physical facilities such as lecturers, labs, practice workshop, libraries, etc Water supply & drainage service providers and the training institutions are not well connected c Communications and community education Propaganda, education and dissemination of laws on environmental protection to the population community are relatively restricted; enforcement of policies and laws on environmental protection is not well observed, valid and effective Benefits of raising the community awareness on launching wastewater management activities are not clearly recognized by the drainage and wastewater treatment companies 1.3.3   O&M costs Actual operating costs must be funded by the local budget as Operation and Maintenance (O&M) costs cannot be covered by wastewater collection fees O&M costs of urban WWTPs are largely depended on treatment capacity and technology as specified in Decision No 451: 2015 / QD-BXD In fact, expenditure for wastewater system O&M is mainly relied on annual expenditure funded by the Provincial/Municipal People's Committee through the Department of Finance and allocated to the Department of Construction The wastewater fee is found in the water consumer’s invoices Water supply revenue from such fee is annually paid to the municipal or provincial budget to redistribute to the drainage enterprises 1.3.4   Technology and technical issues a Drainage and wastewater treatment technology Consistent criteria and implementation procedures have not been available to evaluate and select the drainage and wastewater treatment   technology for cities, industrial parks and hospitals Feasible technologies such as: combination of concentrated and distributed wastewater collection and treatment, gradually upgrading the posttreatment water quality, ensuring the solvency of service users, etc., are not the top priorities of consultant and decision makers b Technical issues The above analysis unveiled that: Technical and financial conditions for study and launch of wastewater drainage and treatment technology, etc., are relatively restricted; it lacks the environmental pollution treatment solutions and technologies suitable with the regional and local conditions or at river basins as well as good response to the climate change and seawater rise in drainage and wastewater treatment activities is not found 1.4   Existing conditions on sustainable operation of the world’s WWTPs 1.4.1   Existing conditions on sustainable operation of WWTPs in some countries in the world Root causes of WWTPs’ ineffective operation may include: Degradation of infrastructure, inactive pumping station, leakage pipeline and malfunction of wastewater treatment works Many plants are also left (or not operated) due to insufficient O&M expenditure or technical capacity to fulfill the tasks, especially at local level and upon control by the restricted management systems 1.4.2   Overview about the financial management policies and mechanisms to ensure the WWTPs’ sustainable operation in the world It is not simple to strengthen the wastewater management and operation performance and some problems (such as water discharge management, financial aspects, etc.) must be completely handled 1.4.3   Existing conditions on evaluating the sustainable operation of the world’s WWTPs 1.4.3.1   Evaluation of Greek WWTP’s sustainable operation The evaluation of WWTPs’ sustainable operation aims to set up the methods and apply such methods to evaluate 14 Greek-based WWTPs in the context that it not only involves in compliance but also specific aspects related to other issues such as environment, technique, economics and social affairs and then each plant's sustainability may be evaluated[44] 15   the criteria groups and criteria (demonstrated in Table 3.4 and Appendix 3.6) Conclusions of Chapter Chapter has successfully setup the scientific basis, analyzed and selected the proper research methodologies Requirements on urban WWTP’s sustainability must be set forth to design and develop the evaluation criteria as well as techno-economic indicators to ensure the plant’s good operation The study applies the theoretical analysis and synthesis method, summarizes the literature review, determines the weights, and analyzes AHP and expert consultation method Such methods mutually support each other and well adapt to determine the weights of criteria Expert method uses the intelligence, exploit the evaluation viewpoint of high qualified experts to review and judge a problem, a scientific event, particularly sustainability in WWTPs’ operation to give out the advises which are well matched with the practice on such sustainability activities The Analytic Hierarchy Process (AHP) method has been applied to determine the weights of evaluation criteria to summarize the sustainable development of WWTPs as AHP is a technique to decide and arrange the evaluation criteria by significance Thanks to that a most smart decision may be found 16   CHAPTER 3: DESIGN EVALUATION CRITERIA AND TECHNO-ECONOMIC CRITERIA TO ENSURE URBAN WWTP’SSUSTAINABLE OPERATION 3.1   Design evaluation criteria for sustainable development of WWTPs Upon determination of evaluation criteria for WWTP’s sustainable operation, the consultation table has been designed in the form specified in Appendix 3.1: - Evaluate sustainable operation of WWTPs by criteria groups New WWTPs are recorded with sustainable operation if total score of 70-100 for criteria groups is agreed by the experts: Total score of criteria in column “Max score value” and “Min score value” is 100 and 70, respectively - The main findings from the MoC-level study “Investigation and proposal of factors to select the proper urban wastewater treatment technology for regions in Vietnam” launched by Ass.Prof.Dr Tran Duc Ha [9] unveiled that, Min value of 65 is technologically taken In addition to the technology factors, other aspects such as economic efficiency, adaptability with climate changes, etc., have been considered hereof The score of sustainable WWTP is 70 in accordance with the expert consultation results Such 70 score threshold is used as the minimum threshold to evaluate the sustainable WWTPs Score of expert-based criteria is tabled in Table 3.4: Contents of this appendix demonstrate the mean of Max and Min scores, corresponding to each criterion Within the contents hereof, the evaluation criteria for the urban WTTP’s sustainability is based on total score of criteria higher or equal to 70 scores (Min scores) Therefore, weights of Min score criteria of consultation table are determined Calculations of AHP-based evaluation model are supported by Expert choice 11.0 Results are shown in Table 3.4 (table results are converted with weights multiplied with 100%): 17   Table 3.4 Weights of criteria (determined by Expert choice 11 Software) Weights Weight among among Criteria criteria criteria group (%) set (%) Wastewater treatment capacity and 100 33.7 efficient The Plant’s actual capacity must 37.2 12.5 ensure to cover project site Treatment must be qualified with the 39.4 13.3 environmental standards for basic contaminant indicators in domestic wastewater (SS, BOD, TN, TP, coliform, etc.) Treatment must be qualified with the 23.4 7.9 environmental standards for some pollution criteria available in the production and service wastewater, etc., in the project site Appropriateness of wastewater 100 15.2 treatment technology with local conditions Selected wastewater treatment 46.3 7.0 technology is suitable with the local natural conditions and load bearing capacity of receiving source The technology is advanced and 28.0 4.3 suitable with the available science and technology conditions in the area Wastewater treatment technology 25.7 3.9 must be well matched with the local management and operation capacity O&M costs 100 20.9 O&M costs are low 53.2 11.1 Energy savings and efficiency and 25.7 5.4 energy recovery of equipment and works are feasible 18   Treatment costs are saved thanks to recovery and reuse of wastewater, waste sludge and biogas Stable operating conditions of works and equipment Operation of works and equipment is not complicated Equipment and its components are easily replaced Adaptability with adverse impacts of climate changes and input factor changes Treatment efficiency is ensured in the conditions that the wastewater is characterized by salt concentration and sudden high temperature Treatment efficiency is ensured in the conditions that the input wastewater is characterized by varied contents of SS, BOD and other pollution criteria It is possible to store water when the input wastewater flow rate is increased for long time due to storm and rain Safety and environmental friendliness Wastewater treatment works not cause bad odor, surrounding environmental pollution, noise, less incidents and wastewater leakage, reducing the soil, underground water source and surface water pollution risks of surroundings WWTPs are located far from the residential areas and sensitive ecosystem zone, making use of natural conditions to enhance the wastewater cleaning, restricting the bad odor and noise, etc Cleaning conditions and working 21.1 4.4 100 12.5 41.7 5.2 32.8 4.1 100 7.7 39.3 3.05 39.3 3.05 21.4 1.6 100 49.8 10 5.0 30.2 3.0 20.0 2.0 19   conditions in WWTPs are qualified with the standards promulgated by the Ministry of Health Priority sequence of criteria group is determined as follows: Wastewater treatment capacity and efficiency>O&M costs>Suitability of wastewater treatment technology with the local conditions> Operating conditions of works and environment > Environmental friendliness and safety > Adaptability with adverse impacts of climate change and input factor changes Two criteria groups of Wastewater Treatment Capacity and Efficiency and O&M Costs have the highest significance level of 33.7 and 20.9, respectively and this is completely suitable with the practice Such two criteria groups are essential and necessary for the wastewater treatment plants Concretely, the system must be properly and effectively functioned (Criteria group of Wastewater Treatment Capacity and Efficiency) and the system must be qualified with the economic criteria (O&M cost criteria group) such as investment expenditure, O&M costs, etc 3.2   Development of techno-economic criteria to ensure sustainable operation of urban wastewater treatment plant 3.2.1   Technology criteria group For the technology criteria grop, the treatment efficiency criteria is the most important one Moreover, in order to evaluate the best performance of WWTP’s technology, criteria on appropriateness of wastewater treatment technologies and local conditions, good adopt and adapt with climate changes as well as criteria on impacts of WWTPs on surrounding environment 3.2.1.1   Water discharge capacity and mode criteria Discharging mode is another basic factor related to calculation of water drainage network and wastewater works Urban wastewater discharging mode is depended on water consumption mode and characterized by non-regulating water discharge coefficient Kch Kch refers to the ratio of discharge flow rate of the highest water consumption hours of the highest water consumption day (qh,max) and 20   wastewater flow rate of average water consumption hours of average water consumption day (qh,tb) 3.2.1.2   Wastewater Treatment Efficiency Criteria Wastewater treatment requirements (level): Treatment is qualified with level A of QCVN 40:2011/BTNMT or QCVN 14:2008/BTNMT Currently, the wastewater pollution is mainly evaluated by parameters as follows: SS; BOD5; TN, TP; Coliform According to QCVN 40-MT:2011/BTNMT: Consumers have domestic and urban wastewater volume greater than or equal to 1500 (one thousand and five hundred) cubic meter/day and night (m3/24h): Maximum allowable value of pollution parameters in domestic and urban wastewater upon discharge into the wastewater receiving source is calculated by following formula: Cmax = C x Kq x Kf 3.2.2   O&M criteria group 3.2.2.1   Suitability with the local conditions: Selected wastewater treatment technology must be well matched with the urban conditions such as natural characteristics (terrains, engineering geology, hydro-geology, climate and weather, etc.); socio-economic conditions (urban level, land use conditions and structure); urban development planning characteristics; the project’s financial capacity, etc 3.2.2.2   Adaptability with climate change In order to guarantee sustainable operation of urban WWTPs, the climate change-related criteria must be considered, namely: -   Treatment efficiency in the conditions that the wastewater is characterized by salt concentration and sudden high temperature -   Treatment efficiency in the conditions that the input wastewater is found with contents of SS, BOD and other variable pollution criteria -   Water storage capacity for a long time due to increase in storm, flood and works (regulating tanks, wastewater stabilizing reservoir, etc.) 3.2.2.3   Environmental friendly safety 21   When efficiency of urban wastewater treatment production line is evaluated, it is required to take care about issues such as bad odor restriction and treatment capacity, generated waste sludge volume and sludge treatment method, etc 3.2.3   Regulation and management criteria group 3.2.3.1  Criteria on WWTP operator management mechanism The enterprise form of WWTP operator is mainly single member liability limited company or Joint Stock Company operating under the Law on Enterprises and managing the water drainage assets and wastewater treatment in accordance with the contract signed with the Owner under the Decree No.: 80/2014/ND-CP 3.2.3.2   Management and operation organization Corresponding to each available wastewater treatment enterprise form of Single Member Liability Limited Company or Joint Stock Company, the management apparatus of wastewater treatment enterprises is generally structured in accordance with the aforesaid diagrams in Figure 3.1, Figure 3.3 and Figure 3.3 3.2.3.3   Asset Management According to the Decree No 80/2014/ND-CP of the Government dated August 2014 on water drainage and wastewater treatment, for urban water drainage system, the concentrated rural residential area is invested by the State budget The water drainage unit selection is complied with the applicable legal regulations on supply of public products and services The water drainage unit must be supported by the necessary manpower, equipment and technical facilities to fulfill the requirements and tasks of rainwater and wastewater drainage system operation and management The drainage unit shall own the water drainage system selected in the area under its management The drainage system management and operation contract must be made and entered by and between the owner and unit assigned to manage and operate the water drainage system This is the legal document is legally recognized 3.2.4   Financial criteria group 3.2.4.1   Water drainage service charge indicator 22   O&M costs of WWTPs are determined in accordance with the Circular No 13/2018/TT-BXD dated 27 December 2018 In addition to O&M costs, the service charge also includes other expenses: Fundamental construction investment expenses; redevelopment expenses; external socio-economic factors; environmental factors and climate changes Wastewater treatment service charge is setup from O&M costs in accordance with the principles of Comprehensive Management of Water Resources as illustrated in Figure 3.5 below Environmental factors, climate changes External socio-economic factors ECONOMIC PRICE OF WATER Re-development expenses Fundamental construction investment FULL PRICE OF WATER QUALIFIED WATER PRICE O&M costs 3.2.4.2   Income of WWTPs In order to obtain sustainable operation of WWTPs, the plant income must be collected in accordance with the water drainage service charge from: -   Expenditures from wastewater fees -   Expenditures from the State budget -   Expenditures from grants: ODA of various countries, WB, ADB, JICA, etc 3.2.4.3   O&M cost savings Annual expenses for urban wastewater treatment are very high; meanwhile a large amount of post-treatment wastewater and waste sludge may be reused On the other hand, by various technical solutions, it is possible to save the energy during equipment operation In order to reduce the O&M costs for urban WWTPs, it is possible to minimize the power consumption of equipment, recover and reuse the wastewater, waste sludge and formed biogas, etc 23   3.3   Application of techno-economic criteria and indicators to ensure the operation sustainability of Bac Ninh City’s WWTP 3.3.1  Description of water drainage system and Bac Ninh City’s WWTP Bac Ninh City’s WWTP is constructed at Kim Chau commune, Bac Ninh City with capacity of: 17,500 m3/day and night (by 2020), its construction area is ha, commencement year was 2013 It is recognized as a common water drainage system supported by innovative SBR technology The plant is designed to ensure that the post-treatment wastewater quality is qualified with Type B of QCVN 40:2011/BTNMT On 25 September 2015, the People’s Committee of Bac Ninh promulgated the Decision No 372/QD-UBND on establishing Bac Ninh Sewerage and Wastewater Treatment Co., Ltd with 100% State own capital under the ownership of the People’s Committee of Bac Ninh On December 2015, the People’s Committee of Bac Ninh promulgated the Decision No 500/QD-UBND on equitiztion of Bac Ninh Sewerage and Wastewater Treatment Co., Ltd Accordingly, Phu Dien Join Stock Company held the shareholding of 65% 3.3.2   Evaluation of operation sustainability of Bac Ninh Wastewater Treatment Plant In addition to analyze the operation advantages and disadvantages of Bac Ninh WWTP in accordance with the evaluation criteria using respective weights, the expert method is applied through consultation table on plant scoring (consultation table is described in Appendix 3.8) Scoring each evaluation criteria of WWTP’s sustainable operation is shown as follows: - Expert’s score with 1-100 scale for each criterion - If wastewater treatment plant’s criteria are qualified, score of such criteria shall be determined within the range of 70-100 scores - If wastewater treatment plant’s criteria are disqualified, score of such criteria shall be 70 above level (70 scores) Therefore, Bac Ninh WWTP is recorded with sustainable operation by ensuring the actual capacity, wastewater treatment level, guaranteeing the economic efficiency in accordance with the local conditions (material sources for wastewater treatment, operation qualification, environment friendliness and safety, etc.), well adapting with disadvantages of climate changes, etc., and widely accepted by the local community 3.3.3  Application of techno-economic criteria and indicators to ensure the operation sustainability of Bac Ninh WWTP Possibility that Bac Ninh WWTP is guaranteed with sustainable operation during operation and management of Bac Ninh WWTP under the proposed techno-economic criteria is summarized in Table 3.12 Table 3.12 Application of techno-economic criteria to ensure sustainable operation for Bac Ninh WWTP No TechnoBac Ninh Plant economic criteria Technology criteria group Discharge -Actual capacity: 13,000 m3/day capacity and (2016) mode criteria 2018: 16,500 m3/day -Designed capacity: 17,500 m3/day -Wastewater treatment efficiency criteria Coefficient Kq=0.9; Kf = 0.9 Operation and management criteria group Operators are available in the areas Appropriateness Equipment and materials may be with the area replaced -Adaptability SBR technology may be well matched with climate with the capacity fluctuation change 25000 m3 stabilizing reservoir is available Requirements Connection percent > 80% Wastewater treatment requirements: treatment is qualified with Level B of WCVN 40:2001/BTNMT or QCVN 14:2008/BTNMT O&M conditions are suitable with the area The system operates in the conditions of failure, change in capacity and input water quality Comments Evaluation High connection percent, qualified with technoeconomic criteria Qualified (according to the monitoring figures of DONRE and Lab of Wastewater Treatment Plant Qualified Suitable, qualified Qualified ASBR is highly flexible The bio reservoir is stable and able to store posttreatment Qualified Qualified 25   Safety and environmental friendliness The plant is located far from the residential area without anaerobic treatment works Legislation and management criteria group: Operation Joint Stock Company management of Asset management contract WWTP operation Standardized isolation is applied Emission and noise are complied with the environment code Single Member Liability Limited Company/Joint Stock Company operates under the Decree No 80/2014/BXD Management is complied with the contract and Law on Enterprises - Management organization Joint Stock Company (Phu Dien Company owns 65%), the complete apparatus is available -Asset management Asset management is complied with the contract Asset management is complied with the Decree No 80/2014/BXD Treatment expenses for 1m3 wastewater is VND 8,000 (O&M) Under the Decision No 451/QD-BX of the Minister of Construction dated 21st April 2015 on treatment expenses for m3 domestic wastewater Short-term period: the price is compensated by the State, collecting the environmental protection fees on wastewater Future: price compensation reduction roadmap is applied Financial criteria group -Water drainage service charge -Income WWTPs of O&M costs are covered by the provincial budget Wastewater fee is VND 15,000/m3/person -Possibility of O&M cost savings Bio-tank for sterilization saves the chemicals Natural sludge drying yard is reduced with energy, waste sludge is not reused Wastewater must be reused under QCVN 0702:2016/BXD wastewater It complies with QCVN on environment Qualified Complete Qualified Qualified Moreover, Phu Dien offers the technical support as necessary Strict compliance Qualified High Disqualified O&M costs are only considered without treatment price, including payback depreciation The state’s price compensation roadmap is not designed Thanks to energy and chemical savings, O&M cost savings are obtained Disqualified Qualified Disqualified 26   Conclusions of Chapter -   Select evaluation criteria sets for sustainable development of urban WWTPs -   Prepare the expert consultation table for evaluation criteria sets According to the consultation table, a WWTP operates in a sustainable manner when its score is within the range of 100 scores (Max) and 70 scores (Min) -   According to AHP method, apply Expert choice 11 to determine weights and priority sequence of criteria is shown below: Wastewater treatment capacity and efficiency>O&M costs>Suitability of wastewater treatment technology with the local conditions> Operating conditions of works and environment > Environmental friendliness and safety > Adaptability with adverse impacts of climate change and input factor changes -   Setup the criteria with respective weights, demonstrating the clear decentralization of criteria for sustainability of wastewater treatment system -   Setup the techno-economic criteria group to ensure sustainable operation of an urban WWTP from AHP-based criteria groups The criteria groups include: Technology criteria group, operation criteria group, legislation and management criteria group and financial criteria group -   Apply the criteria and take the collected data from Bac Ninh WWTP to evaluate its sustainability With AHP in combination with the questionnaire consultation data for experts, the plant is scored with 75.39 (over the minimum level of 70 scores) Therefore, Bac Ninh WWTP is evaluated to operate in a sustainable manner -   Apply techno-economic criteria group for Bac Ninh WWTP to specify the plant's stable and sustainable operation after 05 years of operation However, some criteria is not ensured: water drainage service charge criterion is relatively high, only considering O&M costs without treatment price, including payback depreciation; the income is not supported with the State’s price compensation roadmap, income from wastewater reuse is not generated As a number of connections are few, the operating capacity is generally smaller than the design capacity However in rainy seasons, the wastewater flow rate is increased, adversely affecting the equipment 27   operation; sometimes, input BOD is low, resulting in unstable Nitrogen treatment CONCLUSIONS   Main findings 1.1 The Dissertation has successfully designed the evaluation criteria for sustainable development of urban WWTPs -   Select evaluation criteria sets for sustainable development of urban WWTPs: Wastewater treatment capacity and efficiency; O&M costs; Suitability of wastewater treatment technology with the local conditions; Operating conditions of works and environment; Environmental friendliness and safety and adaptability with adverse impacts of climate change and input factor changes -   Prepare the expert consultation table for evaluation criteria sets According to the consultation table, a WWTP operates in a sustainable manner when its score is within the range of 100 scores (Max) and 70 scores (Min) -   Weights and priority sequences of evaluation criteria groups of sustainable operation of a WWTP are successfully determined in accordance with the Analytic Hierarchy Process (AHP) method and Expert choice 11 software (1) Wastewater treatment capacity and efficiency; (2) O&M costs; (3) Suitability of wastewater treatment technology with the local conditions; (4) Operating conditions of works and WWTP equipment; (5) Environmental friendliness and safety; (6) Adaptability with adverse impacts of climate change and input factor changes with respective weights: 33.7; 15.2; 20.9; 12.5; 10.0 and 7.7 Setup the criteria with respective weights, demonstrating the clear decentralization of criteria for sustainability of wastewater treatment system 1.2 The techno-economic criteria for sustainable development of urban WWTPs have been successfully designed by the study -   Six (06) evaluation criteria groups are the theoretical and scientific basis to design and develop the necessary techno-economic criteria set to ensure the sustainable operation of WWTP, including 28   four (4) criteria groups: Technology; O&M; Legislation; and Finance -   The Study has successfully designed the method of applying the techno-economic criteria to evaluate the investment efficiency, operating performance and adaptability with climate changes of available urban water drainage and wastewater treatment works 1.3 Evaluation criteria and techno-economic criteria are applied to ensure the sustainable development of Bac Ninh WWTP -   Application of evaluation criteria for Bac Ninh WWTP operated by Bac Ninh Sewage Joint Stock Company under the asset management contract unveiled that Bac Ninh WWTP is a sustainable operation with score of 75.39 However, some criteria is not ensured: water drainage service charge criterion is relatively high, only considering O&M costs without treatment price, including payback depreciation; the income is not supported with the State’s price compensation roadmap, income from wastewater reuse is not generated As a number of connections are few, the operating capacity is generally smaller than the design capacity However in rainy seasons, the wastewater flow rate is increased, adversely affecting the equipment operation; sometimes, input BOD is low, resulting in ineffective Nitrogen treatment, etc   Recommendations -   In order to conveniently and suitably apply for each urban WWTP in various regions, the techno-economic criteria should be completed: All criteria must be quantified to be the basis to launch the solutions for urban WWTP’s sustainable and stable operation Total score of criteria should be divided into the smaller scale to decentralize the results, facilitating WWTP’s sustainable development -   With strengths of AHP, max score weights may be used to compare the sustainable operation of urban WWTPs with each other Therefore, AHP method should be further developed in benchmarking and rating the urban WWTPs   LIST OF PUBLICATIONS   Tran Duc Ha, Do Thi Minh Hanh, (2015), «Possibility of reusing wastewater, waste sludge, biogas and energy savings to reduce the urban WWTP’s O&M costs», Water Supply & Drainage Magazine, vol (102), pp 40-43, ISSN 1859-3623   Tran Duc Ha, Do Thi Minh Hanh, (2016), «Development of operation management program for urban WWTP’s sustainable operation», Construction Magazine, Vol 5-2016, pp 81-84, ISSN 0866-0762   Do Thi Minh Hanh, Tran Duc Ha, (2016), «Evaluation criteria and method of urban WWTP’s sustainability», Vietnam Water Supply and Drainage Magazine, Vol (110), pp 74-77, ISSN 1859-3623   Do Thi Minh Hanh, Tran Duc Ha, (2019), «Combination of AHP and expert consultation to design the evaluation criteria of urban WWTP’s sustainable operation», Environment and Urban Magazine, Vol 120+121, pp 38-43 and Vol 124, PP 42-48, ISSN 1859-3674 ... with 100% State own capital under the ownership of the People’s Committee of Bac Ninh On December 2015, the People’s Committee of Bac Ninh promulgated the Decision No 500/QD-UBND on equitiztion... Thi Minh Hanh, (2016), «Development of operation management program for urban WWTP’s sustainable operation», Construction Magazine, Vol 5-2016, pp 81-84, ISSN 0866-0762   Do Thi Minh Hanh, Tran... has been still established in the drainage management enterprises b Human resources The world cutting-edge technologies in drainage and wastewater treatment have been approached and applied in