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Do Thi Minh Hanh DEVELOPMENT OF EVALUATION CRITERIA AND TECHNO-ECONOMIC CRITERIA TO ENSURE SUSTAINABLE OPERATION OF URBAN WASTEWATER TREATMENT PLANT Major: Environmental Technology, Wa

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

1 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 4 December 2018, Vietnam was the home of 819 cities, including: 2 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 5 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 5 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

2 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

3 Subjects and scope of the research

-   Subjects of the research: Management, operation and

maintenance of urban WWTPs

-   Scope of research: Urban WWTPs in Vietnam

4 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 economic-technicalindicators 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

techno   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

Figure 0.1 Summary of research contents and method applied herein

propose and determine weights of sustainability evaluation criteria in operation of WWTPs

Ninh City’s WWTP in accordance with the techno-economic criteria

7 Structure

In addition to preface, conclusions, recommendations, appendix and list of publications, the study comprises of 3 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)

General study on urban wastewater and sustainable operation of urban WWTPs

Data collection, literature review and analysis and evaluation

Quantitative analysis and evaluation in combination with expert consultation

Selection of proper evaluation criteria groups for urban WWTPs’

sustainability

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)

Analyze by AHP (supported

by Expert Choice 11 Software)

Evaluate and adjust the main findings by data collected at BacNinh City’s WWTP

Design the economic criteria groups to ensure sustainable operation

techno-of urban WWTPs

Discuss the main findings and propose the solutions

on enhancing the 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

- Wastewater

treatment

performance

- Management O&M criteria group: Financial criteria

group:

-Appropriateness with

local context - Water drainage service charge

-Adaptability with

climate change -Income of WWTPs

- Safety and environmental

friendliness -O&M cost savings

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

3 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

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 post-treatment 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

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]

With reference to the questions, the quality or quantity consultancy table given for each criterion is completed Results of such criteria evaluation are used for subsequent standardization and valid as the reference standard in the WWTP system

1.4.3.2   Evaluation of wastewater treatment sustainability in

Sweden

In order to illustrate the sustainability of wastewater drainage and treatment system, three various scenarios are used with three comparative examples from three different countries: Sweden, South Africa and Mexico Then it is evaluated by a comprehensive comparison methodology [72]

Upon comparison among Sweden, South Africa and Mexico, it is found that various systems are evaluated to have advantages and disadvantages

in its respective settings The evaluation results are also unveiled that the evaluation results are depended on the context of such three countries

Conclusions of Chapter 1:

Intensive investments from various financial resources have been launched by Vietnamese Government in the fields of water drainage and environmental sanitation fields for the cities since many years However, due to various reasons, including the technical reasons such as improper wastewater treatment technology, investment indicators of water drainage system are asynchronous and characterized by the non-guaranteed operation qualification, low wastewater connection percent, etc Such factors make the invested wastewater treatment and drainage systems operate ineffectively Adverse impacts of climate changes are increasingly clear for Vietnam and urban wastewater drainage and treatment is one of the activities to be seriously affected

Main factors to ensure a sustainable operation of an urban WWTP include treatment technology and proper operation and management Such fitness must be evaluated in accordance with the criteria related to the technical, environmental, socio-economic factors Therefore, such criteria must be analyzed, selected and quantified in combination with the consultation of experts and managers, etc., who are extensively experienced in the fields of wastewater drainage and treatment

The experience of countries in the world unveiled that evaluation of WWTP’s sustainability must have a panorama on considering the criteria in any various aspects such as economics, techniques, environment and socio-economics and the criteria significance must be

determined, corresponding to the various environment and economic viewpoints, etc

CHAPTER 2: SCIENTIFIC BASIS AND RESEARCH

METHODOLOGY 2.1   Scientific basis to develop the evaluation criteria and

indicators, ensuring the sustainability of urban WWTPs

climate changes

The technical criteria’ adaptability with the climate change impacts is demonstrated by the selected wastewater treatment technology line which may prevent the salt water intrusion upon tide and heavy rains in the coastal cities Works arranged in the WWTPs must process and well adapt with the BOD and salt contents in the wastewater and act against the high material oxidization, etc WWTPs must be located at high terrain Such plants must well operate in the high salt content conditions WWTPs must be able to retain water for a long time

2.1.3   Evaluation criteria of urban WWTP’s sustainability

Evaluation criteria of wastewater treatment technologies are proposed in Table 2.2 below:

Table 2.2: List of evaluation criteria for urban WWTP’s sustainability

efficiency

The Plant’s actual capacity must ensure

to cover project site Treatment must be qualified with the environmental standards for basic

contaminant indicators in domestic wastewater (SS, BOD, TN, TP, coliform, etc.)

Treatment must be qualified with the environmental standards for some pollution criteria available in the production and service wastewater, etc., in the project site

Energy savings and efficiency and energy recovery of equipment and works are feasible

Treatment costs are saved thanks to recovery and reuse of wastewater, waste sludge and biogas

wastewater

technology with local

context

technology is suitable with the local natural conditions and load bearing capacity of receiving source

The technology is advanced and suitable with the available science and technology conditions in the area

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

environmental

friendliness

WWTPs are located far from the

ecosystem zone, making use of natural conditions to enhance the wastewater cleaning, restricting the bad odor and noise, etc

Cleaning conditions and working conditions in WWTPs are qualified with the standards promulgated by the Ministry of Health

2.1.4   Techno-economic criteria to ensure the urban WWTP’s sustainability

According to 6 selected criteria set and application of proper analytic methods, techno-economic criteria sets may be designed and developed to ensure the operation sustainability and stability of a WWTP The proposed techno-economic criteria are shown in Table 2.3:

Table 2.3: List of techno-economic criteria to ensure sustainable operation of WWTP

criteria group

Techno-economic criteria

1 Technology Wastewater capacity and mode

2 O&M Adaptability with local conditions

Adaptability with climate changes Safety and environmental friendliness

3 Legislation and

management Management mode on operation of WWTP operator

Management Asset management

4 Finance Water drainage service charge

Income of WWTPs Possibility of O&M cost savings Each of criteria group may be based on various criteria The various criteria groups may share some indicators, creating an interwoven matrix demonstrated in Figure 2.4

criteria and indicators

2.2.1   Theoretical analysis and synthesis method

This method aims to study various literatures on existing conditions

of urban WWTPs and related jurisdictions

2.2.2   Field trip survey method

The method aims to obtain the data on WWTPs to ensure the evaluation criteria sets and techno-economic indicators to ensure the sustainable development concentrated urban WWTPs, nationwide

2.2.3   Weighting method of criteria

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

Urban WWTP’s sustainable operation

Criteria group 4

Stable operating conditions of works and equipment

Criteria group 5

Safety and environmental friendliness

Criteria group 6

adverse impacts of climate changes and

management

O&M

Techno-economic criteria for urban WWTP’s sustainable operation

Figure 2.4: Relation between criteria groups and techno-economic criteria groups