Phương pháp đánh giá dòng chất thải rắn: Nghiên cứu tại các đô thị lớn của Việt Nam

Hgi nghi Khoa hgc ky niem 35 ndm Vien Khoa hgc vd Cong nghe Viet Nam - Hd Not 10/2010<br /> <br /> <br /> PHirONG P H A P D A N H G I A DONG C H A T T H A I R A N :<br /> N G H I E N CUtJ TAI cAC DO THI LCfiV CUA VIET NAM<br /> • • •<br /> <br /> Ngo Kim Chi, Nguyen Xuan Dung, Pham Quoc Long, Dang Ngoc Phu-gng<br /> Vien Hoa hgc cac Hgp chat thien nhien<br /> e-mail: chikimngo2008(^gmail.com<br /> Tom tat:<br /> Bdi bdo trinh bdy mdt phdn ket qud ciia cdc nghien cicu da dupe thuc hien vi sir<br /> dung phuang phdp ddnh gid ddng chdt thdi rdn khi dieu tra hien trgng vd hiiu qud ciia<br /> xic ly, thdi bd vd tdi chi chdt thdi rdn tgi tgi cdc do thi chinh nhu Hd Ndi, Hdi Phdng,<br /> Hui, Dd Ndng, Tp Hd chi Minh. Cdc kit qud diiu tra vi luang phdt sinh chdt thdi rdn<br /> vd thdnh phdn rdc thdi, diiu tra hiiu qud thu gom, van chuyin rdc. Phuong phdp khdo<br /> sdt quaphiiu diiu tra, khdo sdt thuc dia, phdng vdn sdu cdc bin lien quan vd md hinh<br /> tinh todn vdi sir tro giiip cita mdy tinh la cdc cdng cu cho phep xdy dung cdc phdn tich<br /> ddng chdt thdi rdn, xdy dung quy hogeh tdng thi vi chdt thdi rdn theo cdc tiiu chi<br /> gidm thiiu phdt sinh khi thdi nhd kinh cd liin quan din viec xie ly vd thdi bd, tdi che<br /> rdc tir cdc ngudn. Cdc md hinh cdng nghe thich hpp di thuc day 3R: Gidm thiiu-Tdi<br /> chi-Tdi sir dung cdn som duac chii trpng thuc hien di ngdn chdn, gidm thiiu tich cue<br /> vd hiiu qud cdng som cdng tdt cdc ngudn chdt thdi nguy hgi<br /> Abstract:<br /> The paper cover partial results of the research carried out to determinate the<br /> actual and effectiveness of municipal solid waste treatment, disposal, recycling<br /> based on the results of application of the methodology of evaluating solid waste<br /> flow in major urban areas: Hanoi, Haiphong, Hue, Danang, Hochiminh cities of<br /> Vietnam. The resulted surveys on waste generation rate and composition as well as<br /> the time and motion on solid waste collection and transportation study as well as<br /> the questionnaire, field trips and in deep interview surveys and the computer aided<br /> calculation methods were basic scientific tools for building up the waste flow<br /> analysis and master plan of municipal solid waste. Ln addition, it facilitates to set<br /> up the indicators for waste reduction toward effective GHG emission reduction<br /> from waste generators involved in 3R activities in the solid waste treatment,<br /> discharging and recycling. The appropriate technologies on 3R promotion are<br /> needed to be addressed in order to more effectively prevent against hazardous<br /> substances more as soon as possible with successful results.<br /> <br /> <br /> INTRODUCTION<br /> According to the results of the population censuses collected on 01/04/2009, the population<br /> of Vietnam was 85,789,573 persons, distributed throughout six social-economical regions.<br /> The rural population growth rate was only 0.4% per year; the urban population growth rate<br /> was 3.4% per year [1]. In 1999, only 23.5% of the population lived in urban areas, but in 2009<br /> this figure had risen to 29.6%. At the October of 2009, there were 223 industrial parks (IPs) in<br /> the country [2,3]. The purpose of this paper is summary the results of MSW survey based on<br /> <br /> <br /> 193<br />  Tiiu ban: Moi tru&ng vd Ndng lugng ISBN: 978-604-913-013-7<br /> <br /> <br /> waste flow analysis method have been used to evaluation the MSW and create the waste flow<br /> analysis tools to analyze the MSW in the study are as well as the propose for develop<br /> integrated 3R in Municipal Solid Waste Management (MSWM) in cities of Vietnam [2,4].<br /> <br /> <br /> METHODS<br /> Eight major urban cities and provinces (Hanoi, Haiphong, Hue, Da Nang, Ho Chi Minh<br /> cities and Dong Nai, Binh Duong, Ba Ria - Vung Tau) were selected as study areas. Existing<br /> data was collected from the Statistics Yearbook of Vietnam, Healthcare Statistics Yearbook<br /> 2008 [3], National/Provincial report of Environment, Solid Waste Management (SWM)<br /> survey in Hanoi and other cities based on methodology of quantitative and quality of MSW<br /> survey [8, 9], methodology of Time and Motion survey on MSW in Hanoi 2008-2009 [10],<br /> the methodology of Industrial, Medical waste survey were taken [2]. The calculation of GHG<br /> emission and reduction based on IPCC guideline [6, 15]. The field trip survey at landfill sites,<br /> interviews with provincial Departments of Natural Resource and Environment (DONREs),<br /> Urban Environmental Company (Urenco), Waste Collection and Treatment Facilities<br /> (WCTFs). Related studies have been referenced [1-16].<br /> <br /> <br /> RESULTS AND DISCUSS<br /> a. Solid waste management actual situation<br /> (l)MSWgeneration rate: According to the survey on SWM in Hanoi in 2008, the average<br /> rate of domestic waste generated was 545 - 572 g/person/day [8, 9] in 6 sites of Hanoi during<br /> summer time (rainy season). Another study was done in the winter of the year 2009 (dry<br /> season) presented result of 462 g/person/day'. The domestic waste from the city per person<br /> was higher than the household waste generated rate and depending very much on the<br /> urbanization and the rate of urban population. Urban municipal solid waste volume analysis<br /> of Hanoi and HCM cities was showed the rate of 0.98- 1.0 kg/person/day^ for the urban area<br /> and average of 0.73 kg/person/day- 0.85 kg/person/day for the whole cities during the year<br /> 2008-2009^ Fig. 1 presented MSW generation increase of Hanoi, HCM city causing the high<br /> pressure on the target of MSW Management in the fiiture, Fig 2. The collected waste data<br /> fi-om other study areas showed that waste generation rate were about 0.65 kg/person/day in<br /> Danang^ Hai Phong, Binh Duong; 0.68 kg/per/day in Baria-Vung Tau, 0.73 kg/person/day in<br /> Dong nai and 0.6 kg/per/day in Hue city.<br /> <br /> <br /> <br /> <br /> ' Report of NIES, June 3, 2010 on MSWM toward 3R activities, Hanoi<br /> 2<br /> ' Report of SWM in Hanoi 2008, Hanoi city, 4 inner core districts, 1,135,500 habitants, waste collection rate<br /> ^100%<br /> 3<br /> by four Hanoi Urenco enetprises (XNl, XN2, XN3, XN4), total amount was 1,117 tons/day.<br /> Hochiminh DONRE, Hanoi Urenco data based on actual waste amount at weight bridges 2002-2009<br /> ' 08 (eight) URENCOs's report.,2008: Danang city, 818,300 habitants, waste collection rate was over 96% total<br /> amount l,941,800tons/year; Dong Nai province: 2,290,200 habitants, collection rate 71-75% amount 1 254 ton's/day<br /> Hue city: 334,900 people, collection rate 90%, 180-200 tons/day; Baria- Vung Tau: 961,200 habitants- waste<br /> collection rate 75%; 700 tons/day; Haiphong: 1,845,900 habitants, collection rate 85%, amount of 1 020tons/day- Binh<br /> Duong: 1,072,000 habitants, waste collection rate 70%, amount of 700tons/day; HCM city: 6,611 e'oOhabitants 'waste<br /> collection 95%; 5,527 tons/day; Hanoi: population 3,445,000 habitants at 31 Dec, 2007, waste collection rate 95%<br /> amount of 2,511 tons/day (Source: URENCOs; GSO, Vietnam), data of MSW Hanoi and HCM.<br /> <br /> 194<br />  Hgi nghi Khoa hgc ky niem 35 ndm Vien Khoa hgc vd Cong nghe Viet Nam - Hd Noi 10/2010<br /> <br /> The domestic and industrial waste have been disposed into the non hazardous waste<br /> landfill sites due to a lack of proper control from the generated sources, during the waste<br /> pathway, transportation and treatment.<br /> <br /> 120<br /> <br /> <br /> <br /> <br /> 2008 2015 2020 2025<br /> <br /> m % of MSW collection and treatment<br /> D % of MSW recycled, reused, energy recovered, compsoted<br /> <br /> <br /> Fig. 2: MSW collection, percentage of recycled, reused, recovered, composted to 2025 f5J.<br /> (2) Industrial Waste (IW): The rate of IW recently accounted for 5% to 32.3%'''^'^'''" of<br /> municipal waste in the study areas in which the proportion of HzSW was average over 22%<br /> compared to total industrial waste, varied depended on the cities and IPs [2,12].<br /> (3) Hazardous waste: In the year 2002, the target areas had generated 132,809 tons of the<br /> total (160,000 tons in the nation, compared to 73,275 tons in 1999, SOE 2002-2004). This<br /> number has been increased rapidly by the growth rate of industrial sector. The National IP<br /> development with the target of 65,000-70,000 ha in the year 2015 [12] associated with the<br /> increase of hazardous industrial waste. The generation rate of HzSW from some existing IPs<br /> (0.025 to 0.155 tons/day/ha), resulted in over 0.5 million tons/year was generated in pas year<br /> and predicted to be over 1 million ton/year in the year 2015, in which 57% from IPs of the<br /> study areas, arising the special attention looking for urgent and suitable solutions of SWM in<br /> the IPs and enterprises. Fig. 3 [2, 4].<br /> Industrial w a s t e in IPs 2 0 0 0 - 2 0 0 9 and prediction to 2 0 1 5<br /> tons/day<br /> 6,000,000.00<br /> <br /> 5,000,000.00<br /> <br /> <br /> <br /> <br /> I Non HzSW, Tons/year • HzSW, Tons/year<br /> <br /> <br /> Fig. 3: Increase tendency of HzSW in industrial parks and prediction to 2015<br /> <br /> <br /> 195<br />  Tieu ban: Moi tru&ng vd Ndng lugng ISBN: 978-604-913-013-7<br /> I<br /> The hazardous industrial waste was estimated at 0.002 to 1.88 kg/labor per year depended<br /> on type of industry [2].<br /> The producfion of over 1,200 handicraft villages in the study areas with dye, recycling,<br /> metal production, plafing producfion... generate about 0.8-1 tons of hazardous waste per day<br /> [11,12]. Notably, waste treatment and recycling facilifies of plasfic and electronic wastes are<br /> growing massively in the recent years. These facilities usually invested in simple equipment<br /> and made the procurement of thermal burning waste incinerators for waste reduction and were<br /> put into operation without any control over toxic substances exposure which causes serious<br /> environmental pollufion [12, 13].<br /> (1) Potentials for waste recycling: The household waste composition survey taken from<br /> the areas of study show results indicating that household waste was made up of the following<br /> proportions; the proportion of organic easy composed waste is 55.4%), inert material was<br /> neariy 19.2%, paper waste was 8.86%, plasfic waste accounted for 8.74%, glass was found in<br /> 4.56%) of waste, metal was neariy 2%, rubber made up 1.06%) of waste, unused cloth was<br /> about 0.68%, and hazardous waste ranged from approximately 0.1-0.45% [8,15].<br /> (2) Production of composting in study areas: The capacity of exisfing composting plants in<br /> the study areas accounts for 15% of total MSW that is generated daily in the study areas. Cau<br /> Dien composting plant handles 100 tons/day + 3R-JICA pilot model up to 40 tons/day. Son Tay<br /> (100 tons/day), Gia Lam (100 tons/day), Trang Cat - Hai Phong (200 tons/day), Thuy Phuong<br /> (Hue, 200 tons/day) and Ho Chi Minh composting plants (up to 1,300 tons/day), Bien Hoa (400<br /> tons/day). However, the actual consumption of compost is not as good as expected for many<br /> reasons including quality, price, market expansion, and services. Although compost production<br /> of MSW in the study areas has high potential, these plants always operate under designed<br /> capacity. Nonetheless, the stiady areas need to diversify recycling promotion activities and set<br /> up more demonstration models or pilots on organic waste treatment to make the comparison.<br /> The study area also needs to propose the most suitable technique solution for organic waste and<br /> other recycling materials that are well suited for practice in Vietnamese conditions. Another<br /> recycling kind of food waste from restaurants, food shops and several residential was swine<br /> feeding but this proportion was approximately only about 1.6% of total MSW.<br /> (3) Waste recycling in Hanoi, Ho Chi Minh and in informal sectors of the study areas:<br /> Hanoi and HCM are the two leaders in the waste recycling. Recognizing the importance of<br /> recycling, Hanoi supports the 3R project toward Sound Material Cycle Society and Ho Chi<br /> Minh City supports the 3T. Craft village: There are over 18 waste recycling craft villages<br /> related to Waste of Electronic Equipment (WEE) villages in the study area. The turnover of<br /> national recycling is over 74.8 million SUS (2008), which is an increase of 16% per year and<br /> created jobs for about 90,000 laborers [10, 12, 13, 14]. In many cases, almost aU of the places<br /> where recycled materials are gathered and processed, called recycling craft villages, are<br /> causing large environmental problems for the communities due to the large amounts of<br /> pollution emitted by most of the recycling technology and equipment [10-16]. It was<br /> estimated the volume of MSW is recycled in the urban area of Vietnam was about 22-25% for<br /> the year 2008-2009.<br /> (4)The manual collection, treatment of solid waste in the study area and waste collected<br /> without waste separation at source: The waste collection is almost all done manually from<br /> the handcarts to landfills or the waste treatment facilities. In addition, hazardous waste from<br /> households, business, agricultural and industrial waste was generated and mixed [10] without<br /> WSS. The collection rate was still low due to limits manpower, facilifies and resources. The<br /> <br /> 196<br />  Hgi nghi Khoa hgc ky niem 35 nam Vien Khoa hgc vd Cong nghe Viet Nam - Hd Noi 10/2010<br /> <br /> <br /> WSS is just in initial trial period with difficulties of unawares' generators and the "learning<br /> from the best" to disseminate.<br /> (5) Other hazardous wastes in the study areas: Sludge from the waste treatment system,<br /> waste from chemical hazardous from handcraft villages, industry and household (rate of 0.01-<br /> 0.45% [8, 9] including batteries, acute, thermometers, light bulbs, and solvents) are dumped<br /> daily or open air burning. Additionally, the WEE is now rapidly rising approximately about<br /> 1.0 kg of WEE/head/year (22,344 tons/year in study areas) [13, 14].<br /> An average of 15.5- 18.5 tons/day of healthcare hazardous waste is generated per day in<br /> the study areas [2], this volume could be reduced by the good practices of WSS at healthcare<br /> facilities. Hochiminh city has two incinerators with 4 and 7 tons/day, other cities the<br /> destruction of HzHCSW is done in small capacities and batch operation incinerators (normal<br /> capacity less than 200 kg/batch) and should be under strict monitoring and operation<br /> evaluations, especially for flue gas emission control to sure the reduction of dioxin level.<br /> b. Waste Row analysis and tools for MSW analysis for the GHG potential reduction.<br /> <br /> <br /> K'cno.<br /> i Rccjrclniu<br /> RDCiKUnit<br /> <br /> <br /> <br /> <br /> S a n l a e ft<br /> <br /> <br /> £ncfY^<br /> <br /> <br /> Tr^iimrt<br /> C*mpOHl<br /> <br /> Cn^pniCiHit<br /> MalvriidI (Inv<br /> . ^ I cue<br /> envbpoonictK fecdiBg<br /> <br /> <br /> COMi|K*«lU(N?<br /> f<br /> <br /> <br /> Fig. 4: Shows the MSW management system flowchart of the studied cities<br /> Fig. 4 shows the MSW management system flowchart in which the waste treatment and the<br /> composition of each input flow presented as following: (l)MSW stream Fo is separation by its<br /> composition and contains Food waste (Fd), Wood and Paper, Metal, Glass (WP), and Plastic<br /> (PI). These consist of cellulose, cotton originated waste (Cl), Rubber, Leather, Lignin (Lg), an<br /> Easy Biodegradable substance (EB), No Biodegradable substance (NB) and ash (As).<br /> (2)Recycling included Composting and Re-manufacturing and Swine feeding: One part of<br /> MSW is composted at composting plant where Cl and EB are decomposed and<br /> Remanufactured in the recycling sites and in type of swine feeding. At one part of difficult<br /> continue to compost longer time so that B, Cl, EB, and Lg are decomposed. Generated gas<br /> contains CH4, NH3, and N2O and potential of GHG reduction is calculated based on IPCC<br /> method. One part of composting residue is recovered as organic fertilizer, and others are<br /> landfilled, or incinerated. (3) Incineration: One part of MSW is perfected combustion of the<br /> combustibles is carried out. Generated gas contains only CO2; (4) Landfilling: One part of<br /> MSW is disposes at Landfill and anaerobic decomposition is carried out. Generated gas<br /> contains CO2 and CH4 and potential GHG reduction by CH4 capture and flare.<br /> <br /> <br /> <br /> <br /> 197<br /> Tiiu ban: Moi tru&ng vd Ndng lugng ISBN: 978-604-913-013-7<br /> <br /> <br /> Table: Mass fractions xF0,iof ingredients i inFO<br /> <br /> Cities 1=<br /> <br /> Ha Noi, Hai Phong, Hue, Da<br /> Nang, HCM, Dong Nai, Binh Duong i=Fd; i-WP; i=PL<br /> <br /> Table: Mass fractions of substances j in waste<br /> <br /> Components: Xi,j Xi,j [-]<br /> i =Fd, WP, PL J=Clj=Lgj=EBj=Vo j=As j=Wt<br /> <br /> Table: Mass fractions of elements k in substance]<br /> <br /> Substance: j Xi,j [-]<br /> <br /> xj,k[-]:j=Cl;j=Lg,j=EB,j=NB k: k=C k=H k=N k=0<br /> <br /> The results showed that averagely for the recycling as compost the GHG emission<br /> reduction could be 0.5 tC02 e/ton of MSW, for landfill with CH4 flare was only 0.250tCO2<br /> e/ton of MSW [15] for remanufacturing or used recycling materials was 0.680 tC02 e/ton of<br /> MSW for incineration was about 0.06 tC02 e/ton of MSW and non significant as swine<br /> feeding. The recycling, re manufactured in the recycling sites and use recycled material are<br /> the type of waste treatments permitting to get the maximum GHG reduction.<br /> <br /> <br /> 4. DISCUSSION AND THE ORIENTATION SOLUTION<br /> 4.1 Importance of basic schemes on planning and legal framework is the key factor to<br /> improve the SWM in the study areas. The planning in MSWM should be developed to suit the<br /> speed of development of the socio-economics and natural resource utilization of the cities by<br /> reduction of waste generation per head, increase recycling. Together v«th basic schemes and<br /> planning on SWM, the Monitoring of the regulations, implementation and strengthening of SWM<br /> capacity and improvement ofMSWM fee should be improved and put in proper regulation.<br /> 4.2 Necessity of technologies. Based on the characteristics of waste composition, location,<br /> economic perspectives, the appropriate technologies and strong supports for advance models<br /> such as establishing the Eco cities or biomass cities' vision in which total biomass and<br /> organic waste could be exchanged and converted into either power/heat generation; Etbanol<br /> and Biodiesel fuel. Fertilizers/feed production and plastics or other materials effective<br /> recycling models so that the waste generators will be involved in efficient use of the city<br /> biomass and waste resources. Apply 3R for recyclable materials: construction waste, food<br /> waste, recycling of ashes, waste cooking vegetables, bio diesel fiiel and bio ethanol' other<br /> related measures. Develop the model on gasification technologies, melfing ftimaces helping in<br /> dioxin reduction and complete high temperature combusfion.<br /> 4.3 Countermeasures against toxic substances: Develop the model on gasification<br /> technologies, melting fiirnaces helping in dioxin reduction and complete high temperature<br /> combustion. Technologies on treatment and recycling mercury/asbestos/cadmium levels by<br /> <br /> <br /> 198<br />  Hgi nghi Khoa hgc ky niem 35 ndm Vien Khoa hgc vd Cong nghe Viet Nam - Hd Noi 10/2010<br /> <br /> the improvement of recycling technologies for waste batteries, fluorescent bulbs, isolation<br /> materials as well as reduce the use toxic heavy metals in production and in plastic bags. At the<br /> same time, it should implement the measures to reduce POPs amount and level, development<br /> of policy toward 3R hazardous waste MSWM.<br /> 4.4 Improvement of financial source for MSWM. With the clear basic scheme and<br /> planning, the MSWM need the financial support from Provinces and Government to create<br /> favorable conditions for building new MSW recycling, treatment plants to achieve the target<br /> in the Integrated MSWM strategy up to the year 2020 toward the restriction of landfill use and<br /> greenhouse gas emissions reduction.<br /> 4.5 Promoting citizen and related stakeholders involvement. The citizen, waste generators<br /> participated in WSS and their responsibilities, public awareness rising were also importance<br /> in waste management.<br /> Vietnam has adopted legal document framework on SWM integrated with 3R initiatives<br /> focused more on recycling and there are still many barriers but the demand on capacity<br /> enhancement in 3R and Integrated SWM, especially on hazardous pollution control is highly<br /> essential in the coming period.<br /> <br /> <br /> ACKNOWLEDGMENT<br /> This research was supported by the Institute of Natural Products and Chemistry - Vietnam<br /> Academy of Science and Technology through the co operations, sub contracts and missions<br /> during the implementafion of JICA 3R-HN project in Hanoi 2007-2009 and the JICA Study<br /> on Urban Environment management in Vietnam 2010-2011. The authors would like to<br /> express the great thank to Mr. Nguyen Van Hoa, General Director of Hanoi Urenco, Mr. H.<br /> Yamauchi , Mr. Y. Matsuzawa, Prof S. Sakai, Associate Prof M. Asari for their supports,<br /> comments during the research.<br /> <br /> <br /> REFERENCES<br /> 1. Initial report on the National Census on population 1st April 2009 (2009), "National<br /> workshop on the announcement of the census' results, 2009", General Statistics<br /> Office.<br /> 2. JICA study on improvement of urban environment in Vietnam 2010, "Sub component<br /> industrial solid waste and medical waste ", September 2010<br /> 3. GSO of Vietnam, "Statistical data until 2008 (www.gso.vn) and Healthcare Statistics<br /> Year Book 2008".<br /> 4. Ngo Kim Chi (2010), "Solid waste management associated with the development of<br /> the 3R initiatives: Case study in major urban areas of Vietnam", J Mater Cycles<br /> Waste Manag, 2010, (Accepted)<br /> 5. National strategy on integrated SWM until the year 2025 and the vision to the year<br /> 2050 issued by the Prime Minister on 19 December 2009<br /> 6. 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