In recent years, there have been frequent incidents of odor disturbance caused by landfills, and media reports are not uncommon. Although both the national and local levels are actively promoting the development of the waste incineration power generation industry, due to the wide geographical area, significant differences in natural geography, and different levels of economic and social development in China, landfill may remain the main waste disposal method for a long time in the future. How far can the foul odor from landfills affect? The Key Laboratory of Odor Pollution Control of the Ministry of Ecology and Environment conducted in-depth research on a large landfill site in the south, analyzed the sensory and substance concentrations of the landfill site, quantified the masking effect of temporary film covering on odors and odor substances at night, studied the impact range of odors under different scenarios, and screened the most important odor substances that affect health. This achievement was published in Waste Management in March 2021.

Research methods and findings

Research methods and findings

This study collected a total of 66 samples using a wind tunnel sampler, and analyzed 145 volatile organic compounds (VOCs) and odor emission rates from different sections of the landfill site. The landfill section considered the working cycle of the landfill site in a day, including the process of lifting high-density polyethylene (HDPE) film, garbage dumping in the landfill area, HDPE film covering process, four parts of HDPE film top, and garbage truck dumping platform. The study found that after night film covering, VOCs decreased by 66.80% year-on-year, and odor concentration decreased by 48.26% year-on-year. Night film covering can effectively reduce the emission of pollutants.

Reduction rates of different substance categories and odor concentrations in landfills before and after mulching

Due to the variation of landfill area and height with changes in operations, and the fact that residential areas with odor complaints are generally high-rise buildings, residents on different floors may experience different levels of landfill odor. Therefore, this study calculated the changes in the impact of odor pollution on the population living on floors 10m, 30m, 50m, and 70m at landfill operation heights of 10m, 40m, and 70m, with landfill areas of 5000 m2, 6000 m2, and 7000 m2. Research has shown that with an increase in landfill height (10m-70m), the frequency of odor occurrence in residential areas increases by about 68%; As the landfill area increases (5000-7000 m2), the frequency of odor occurrence in residential areas increases by about 28%; The frequency of odor occurrence varies among residents on different residential floors, and the assessment should take into account residents living on higher floors.

Residents in different residential areas and heights are affected by odors at different landfill heights

Based on the above research, three scenarios were defined: Best case (70m, 5000 m2), Medial case (40m, 6000 m2), and Worst case (10m, 7000 m2), based on the height of landfill operations and landfill area, to elucidate the odor annoyance effect. In the Best case scenario, the protection distance of odor pollution in various diffusion directions is 0.3-3.7 km, and the affected area is about 9 km2; In the Medial case scenario, the protection distance for odor pollution in various diffusion directions is 0.7-6.8 km, with an impact area of approximately 31 km2; In the Worst case scenario, the protection distance of odor pollution in various diffusion directions is 1.4-8.4 km, and the affected area is approximately 57 km2. In addition, this study screened 14 non carcinogenic risk substances and 6 carcinogenic risk substances for health risk assessment. The study found that the halogenated hydrocarbons, especially dichloromethane, in the landfill site had high carcinogenic and non carcinogenic risks.

三种情景下，垃圾填埋场恶臭影响

The odor pollution from landfills has a far-reaching impact, and its odor problem has become one of the main environmental issues of concern to the competent authorities and the surrounding public. Fine management should be implemented in landfills, and the size and shape of landfill operation units should be reasonably planned based on the amount of landfill waste to be disposed of, in order to minimize the exposed area of the operation surface; The coherence and compactness of landfill operations are key to controlling odor pollution in the landfill area. Considering unfavorable diffusion conditions in the evening and at night, operations should be avoided as much as possible during this period; In addition, during the homework period, it is necessary to effectively carry out film covering work, which can effectively reduce the unorganized emission of odors.

Paper link:

https://doi.org/10.1016/j.wasman.2021.03.055