METHODOLOGY
Solid waste management is a combination of management processes from recovery, sorting at source, collection, transportation to processing stage and finally destruction
Effective solid waste classification at the source is essential for successful recycling and resource recovery Implementing a robust waste collection and recycling policy, coupled with financial incentives, can motivate individuals to separate their waste properly In Vietnam, a dedicated network of scrap collectors plays a vital role in the recycling process, handling materials such as paper, bottles, steel, and aluminum.
Collection and transportation of solid waste: Collection and transportation of solid waste to recycling, processing or landfill facilities is a part of solid waste management system
Figure 1: Collect and transport solid waste in Hanoi
Statistics indicate that urban areas generate over 50% of the country's total domestic solid waste annually, with a daily output of approximately 38,000 tons by 2015, up from 32,000 tons in 2014 Specifically, Ho Chi Minh City produces around 6,420 tons of domestic solid waste daily, while Hanoi's figure is 6,739 tons With an average annual increase of 12% from 2011 to 2015, the trend suggests that urban domestic solid waste generation will continue to rise in the future.
Composition of solid waste in Hanoi
Table 1: Composition of solid waste in Hanoi
Source: Ha Noi Capital Development Report to 2030, vision to 2050,
Hanoi Planning and Construction Institute, 2015
Figure 2: Composition of solid waste in Hanoi
According to research of Julia Martínez-Blancoa, Pere Mu˜nozb,
Assumpció Antónb, Joan Rieradevall, Life cycle assessment of the use of
This study investigates the environmental impacts of using compost derived from municipal organic waste for fertilizing tomato crops, comparing it with mineral fertilizers While previous research has primarily focused on specific aspects of composting, this paper aims to assess the entire life cycle of fertilizers, from the collection of organic urban solid waste to their application in agriculture Three fertilizer systems were identified, highlighting the performance of both pilot and industrial sectors based on empirical data The findings indicate that while composting is a crucial process that requires optimization, its effectiveness in gardening is limited compared to mineral fertilizers, particularly when considering load avoidance Notably, no significant differences were found in agricultural production and quality between the two fertilizer types.
In 1999, the European Union's Landfill Directive mandated member states to decrease the disposal of biodegradable waste to mitigate environmental impacts and preserve organic resources This directive has spurred the implementation of measures aimed at enhancing waste classification at the source, as well as improving the collection and recycling of organic municipal solid waste and pruning waste.
Composting municipal solid waste (MSW) not only minimizes landfill waste but also produces a valuable organic fertilizer that enhances agricultural practices This process effectively eliminates various pathogens and odor compounds, contributing to healthier soil Research indicates that the application of such organic fertilizers can significantly reduce weed germination and lower the incidence of plant pathogens, promoting overall plant health and productivity.
Enhancing productivity, quality, and the development of soil microbial communities is crucial, particularly in the Mediterranean region where organic matter content has been declining in recent years Increasing organic matter not only reduces erosion rates but also improves soil moisture and density Additionally, in rural peri-urban areas, utilizing fertilizers from urban sources adds value, while proximity to markets facilitates the sale of agricultural products and shortens delivery cycles.
McConnell et al (1993) identified local restrictions on fertilizer use in gardening due to factors such as increased salt content, heavy metal toxicity, and variations in NPK ratios However, these restrictions can often be mitigated by using organic materials with appropriate ingredients This can be accomplished by optimizing the materials at their source (Hargreaves et al., 2008) and allowing for controlled incubation during the decomposition process.
Recent studies on composting have predominantly concentrated on specific aspects of the composting life cycle, such as emissions and fertilizer usage (Amlinger et al., 2008; Blengini, 2008; Bruun et al., 2006; Cisneros, 2006; Dalemo et al., 1997; Elherradi et al., 2005; Favoino and Hogg, 2008; Guereca et al., 2006, 2007; Guerini et al., 2006; Hansen et al., 2006a; Hargreaves et al., 2008; Sharma and Campbell, 2003; Silva et al., 2007; Tsai, 2008) However, there is a notable lack of environmental quality data concerning the application of fertilizers in horticulture, which may influence transportation, indirect waste generation, and the nutrient supply to plants (Sonesson et al., 2000).
The life cycle assessment (LCA) tool quantifies the environmental impacts and energy consumption linked to composting, following the guidelines set by ISO 14040 This assessment evaluates the entire process, encompassing raw material acquisition, production, usage, end-of-life processing, recycling, and final disposal, to provide a comprehensive understanding of its environmental aspects and potential impacts.
Composting is a sustainable alternative to landfill and incineration for managing food waste, with only 0.77 million tons of the 18.9 million tons of municipal solid waste (MSW) recovered as fertilizer in the US in 2008, primarily from food waste (USEPA, 2009) This process involves the decomposition of organic material by microorganisms in low humidity, aerobic conditions, yielding a nutrient-rich product that can replace peat, fertilizers, and manure in agricultural and horticultural applications such as landscaping and gardening (Levis et al., 2010; Okafor, 2011; USEPA, 2011) Numerous studies have demonstrated the benefits of using alternative fertilizers, including compost, for the production of ornamental plants (Chen et al., 1988; Martinez-Blanco et al., 2011; Raviv et al., 2005; Rea et al., 2009; Russo et al., 2008; Russo et al., 2011) Furthermore, research highlights the environmental advantages of compost in enhancing soil quality.
Incorporating organic matter, nutrients, and electrolytes into the soil enhances its structure, density, and porosity, leading to improved water retention and reduced nutrient erosion and water loss This approach can significantly decrease the reliance on fertilizers, pesticides, and peat, while also boosting the soil's carbon storage capacity, which contributes to mitigating global warming (Favoino and Hogg, 2008; Martínez-Blanco et al., 2009; ROU, 2007) However, it is important to consider that compost production may also have negative environmental effects, including CO2 emissions from fossil fuel consumption during transport and processing, as well as the release of methane (CH4) and nitrous oxide (N2O).
During composting, anaerobic conditions can lead to the release of nitrogen oxides (NOx) and ammonia (NH3) due to denitrification processes, contributing to additional greenhouse gas emissions (Amlinger and Peyr, 2008; Boldrin et al., 2009; Edwards and Williams, 2011).
Life cycle assessment (LCA) is a valuable tool for evaluating and comparing the environmental impacts of various waste disposal methods, including the use of fertilizers By employing standardized data, LCA quantifies the environmental effects across all stages of a product or service's life cycle—ranging from material acquisition and processing to distribution, usage, and end-of-life disposal Researchers have applied LCA to analyze municipal solid waste (MSW) treatment scenarios and to assess the environmental impacts of organic waste treatment, highlighting its importance in sustainable waste management practices.
Life Cycle Assessment (LCA) studies indicate that composting offers a lower environmental impact compared to other organic waste disposal methods, such as landfilling and incineration Research by Andersen et al (2011) examined 12 treatment scenarios, including composting, incineration, and various landfill and wastewater treatment combinations The findings revealed that composting produced the least potential for dust and smoke, ranked second in terms of primary energy demand and acidification potential, and was third in global warming potential among the evaluated options.
Previous Life Cycle Assessments (LCA) primarily focused on the production of compost, with limited studies examining the entire composting process up to its end of life Notably, ROU (2007) conducted an LCA of a wind composting system in Australia, which included an analysis of fertilizer use and the impacts following compost application Similarly, Luske has contributed to this area of research.
RESULTS AND DISCUSSIONS
The amount of greenhouse gases generated from bio-composting from the IPCC calculation model 2006:
Table 3: The amount of greenhouse gases
Air Total the amout of waste 2011
Thousand ton g/kg ton Ton CO2 eq
Figure 5: The amount of greenhouse gases at home composting
Figure 6: Put organic waste to make compost
Compare between HC and CC, the results is calculated base on OpenLCA software and IPCC
- Home composting: 22000 ton CO2 eq
- Centralized composting: 16714 ton CO2 eq
CONCLUSIONS
The analysis of the Life Cycle Assessment (LCA) mechanism in urban solid waste management provides a valuable scientific foundation for selecting appropriate solid waste treatment technologies in Vietnamese cities, particularly in Hanoi, during this period of development.
Applying Life Cycle Assessment (LCA) in waste management offers a scientific and practical solution to the challenges faced by Hanoi and Vietnam as a whole Despite certain limitations stemming from system complexity and insufficient data for comprehensive evaluations, this approach equips policymakers, state management agencies, and experts in waste management with tailored solutions for specific stages and regions.
In light of the limitations identified in this thesis, students will explore additional tools and methodologies to enhance their research and effectively address existing questions that arise within the scope of their study.
We can simultaneously make compost at home or in the concentration area This helps to reduce solid waste to landfill
Composting plays a crucial role in the city's solid waste management strategy, as the quality of organic fertilizer relies heavily on the type of input waste To ensure the effectiveness of the composting facility, it is essential to implement waste separation at the source Therefore, the success of this project hinges on the active participation and support of the entire community.
Bộ Tài nguyên và Môi trường đã công bố Báo cáo môi trường đô thị 2016 tại Hà Nội Nghiên cứu của Nguyễn Phúc Thanh, Lê Hoàng Việt, Nguyễn Xuân Hoàng và Nguyễn Võ Châu Ngân từ Trường Đại học Cần Thơ đã đánh giá tác động của các phương pháp xử lý rác thải đô thị tại vùng đồng bằng sông Cửu Long, Việt Nam, được đăng trong tạp chí Science & Technology Development, Vol 15, No.M1-2012.
Nguyễn Võ Châu Ngân và các cộng sự (2014) đã tiến hành nghiên cứu về lượng phát thải khí Mê-tan từ rác thải sinh hoạt tại khu vực nội ô thành phố Cần Thơ Kết quả nghiên cứu được công bố trong Tạp chí Khoa học của Trường Đại học Cần Thơ, số 31, trang 99-105 Nghiên cứu này góp phần quan trọng vào việc hiểu rõ hơn về vấn đề ô nhiễm môi trường do rác thải sinh hoạt tại khu vực đô thị.
Trịnh Ngọc Tuấn và cộng sự (2014) đã thực hiện một nghiên cứu đánh giá hiệu quả giảm phát thải khí nhà kính của phương pháp ủ so với việc chôn lấp chất thải rắn tại thành phố Huế Nghiên cứu được công bố trong Tạp chí Khoa học và Công nghệ, Trường Đại học Khoa học Tự nhiên, Tập 1, Số 1 Kết quả cho thấy phương pháp ủ không chỉ giúp giảm thiểu khí nhà kính mà còn mang lại lợi ích môi trường đáng kể cho khu vực.
Nguyễn Thị Khánh Huyền và cộng sự (2015) Ứng dụng mô hình IPCC
Năm 2006, nghiên cứu đã được thực hiện để ước tính phát thải khí mê tan từ chất thải rắn sinh hoạt tại thành phố Thủ Dầu Một, tỉnh Bình Dương, được công bố trong Tạp chí Khoa học Trường Đại học Cần Thơ, trang 183-192 Đến năm 2016, Đặng Thị Liên đã thực hiện một nghiên cứu đánh giá phát thải khí nhà kính metan (CH4) từ bãi chôn lấp chất thải hữu cơ tại bãi rác Xuân Sơn, Sơn Tây, Hà Nội, đồng thời đề xuất các biện pháp giảm thiểu phát thải này trong luận văn thạc sĩ về biến đổi khí hậu.
Công ty TNHH một thành viên môi trường đô thị Hà Nội -URENCO (2009,
Báo cáo hiện trạng công tác quản lý chất thải tại thành phố Hà Nội cho thấy tình hình hoạt động của Khu Liên hiệp Xử lý Chất thải Nam Sơn (2015) Đồng thời, nghiên cứu của Nguyễn Thị Kim Thái (2008) tại Trường Đại học Xây dựng Hà Nội đã chỉ ra phương pháp ủ sinh học nhằm nâng cao hiệu quả xử lý chất thải rắn hữu cơ phù hợp với điều kiện Việt Nam.
Công ty tư vấn xây dựng công nghiệp và đô thị Việt Nam đã thực hiện báo cáo nghiên cứu khả thi về việc nâng cấp nhà máy chế biến rác thải sinh hoạt thành phân bón hữu cơ tại Cầu Diễn, Hà Nội vào tháng 4 năm 1998.
IPCC, 2006 Guidelines for National Greenhouse Gas Inventories Prepared by the National Greenhouse Gas Inventories Programme, Eggleston, H.S., Buendia, L., Miwa, K., Ngara, T., and Tanabe, K (eds) IGES, Japan (2006)
Thanh N.P., Matsui Y., “Evaluation of the alternative treatment methods for GHG emission mitigation from municipal solid waste management: case study of Ho Chi Minh City, Vietnam”, As J Energy Env
ISO, Environmental standard ISO 14040, Environmental management— life cycle assessment—principal and framework,
World Bank, Vietnam Ministry of Environment and Natural Resources, Canadian International Development Agency, Viet Nam Environment Monitor: Solid Waste (2004)
Hoang Minh Giang, Nguyen Duc Luong, and Luong Thi Mai Huong conducted a study assessing the potential for greenhouse gas mitigation through various household solid waste treatment technologies Their findings, published in Waste Tech, Volume 1, 2013, pages 10-16, highlight the effectiveness of these technologies in reducing emissions and promoting sustainable waste management practices.
Andersen JK, Boldrin A, Christensen TH, Scheutz C Home composting as an alternative treatment option for organic household waste in Denmark: An environmental assessment using life cycle assessment- modelling Waste Management 2012; 32:31-40
Joan C, Julia MB, Xavier G, Adriana A, Antoni S, Joan R, Xavier F Environmental assessment of home composting Resources, Conservation and Recycling 2010; 54:893-904
Lou XF, Nair J The impact of landfilling and composting on greenhouse gas emissions - A review Bioresource Technology 2009; 100: 3792-3798.