Trends in greenhouse gases emissions and air pollutants from the waste management sector have been balanced since 1990. More information on emissions trends from the waste management sector in Slovakia.
Total emissions
The trend of emissions from waste management has been balanced throughout the observed period since 1900. The most important gas is methane with more than 92% of greenhouse gas emissions in the sector, followed by N2O with almost 8%. Most emissions come from landfills and subsequently from wastewater.
The waste sector accounted for 5% of total greenhouse gas emissions in 2021. Since 1990, methane emissions have increased by more than 100% due to the use of a cumulative methodology in the solid waste landfill category. A similar, although not so significant, trend is expected in the coming years. The volume of emissions from landfills also significantly depends on the implementation of landfill gas capture and use.
This sector also includes cremations of human and animal remains, which are also a source of air pollution by emissions of heavy metals and POPs.
Wastewater management also releases air pollutants and greenhouse gases (CH4 and N2O). In general, emissions of POPs as well as NMVOC, CO and NH3 occur in wastewater treatment plants, but are negligible.
The most significant decrease in cadmium emissions occurred in 2003, when municipal waste incinerators introduced new, more environmentally friendly technologies. There was a significant decrease in PCDD / PCDF emissions in the waste sector in 2006.
Emission trends by type of waste management
Trends in emissions and removals of greenhouse gases and pollutants from the waste management sector by individual activities have been balanced since 1990. More information on emission trends in waste sector by individual activities in Slovakia.
Emissions by category
Landfilling of waste is a significant source of methane emissions, which are released in the form of landfill gas. Since very few landfills in Slovakia have a sophisticated system of capturing and recovering landfill gas, it is released directly into the atmosphere. Methane also escapes from closed landfills, from layers of waste stored for up to about 30 years, so it is very important to prevent landfilling. Methane from category 5.A - landfills has a year-on-year growing trend due to the cumulative approach to its calculation.
Wastewater treatment is a significant source of N2O emissions. Due to the improvement of technological processes, its production is decreasing year-on-year.
Other waste management methods, such as incineration and composting, produce only small amounts of methane or nitrous oxide.
The most common methods of disposal are landfills and, to a lesser extent, incineration. When landfill waste decomposes, non-methane volatile organic compounds (NMVOCs) and methane are released into the air, and particulate matter (PM) emissions are released during waste handling.
Incineration is the second most common method of waste disposal in the Slovak Republic. This energy was not used often in the past and the waste was only disposed of. Modern facilities currently use waste as a fuel in energy production or in industrial processes, and waste is thus recovered. In this case, the emissions from combustion are included in the energy sector.
Waste incineration in our country significantly contributes to the amount of dioxins and furans (PCDD / PCDF) that are released into the air. Because dioxins are virtually non-degradable in nature and can persist for hundreds of years, they are stored in animal tissues and thus enter the human food chain. Intake of food, especially meat, fish, eggs, milk and fats, is the most important route of dioxin entry into the human body.
When waste is incinerated, high amounts of heavy metal emissions are also released into the air. Modern waste incinerators effectively capture these substances, but this has not been the case in the past. Heavy metals are stored in the soil and subsequently in organisms from which they are difficult to degrade. Due to the food chain, contamination of organisms gradually increases as predatory animals feed on contaminated organisms. Animals at the end of the food chain, and therefore humans, are particularly vulnerable to heavy metals. The risk is higher especially in coastal areas, where the consumption of marine animals is higher overall.
Waste recycling is not the only sustainable way of recovering waste. One of them is the composting of any organic waste, such as food and garden waste. Organic waste decomposes into mulch within a few weeks, which can be used as soil fertilizer. Many households practice small-scale composting, and large-scale composting systems are being developed to collect organic waste from parks and civic amenities. Similar types of organic waste can also be treated in biogas plants. Unlike composting, here the waste is decomposed anaerobically (without access to air) and biogas is produced, which can be further burned, thus creating energy that can be further used for heating.