Proceedings of the joint international workshop on Ecological Sustainable Waste Management – Energetic Utilization of Organic Waste (Biowaste4E)
Buch in deiner Nähe kaufen
Beschreibung
Every day, the world's population produces about 3.5 million tons of waste. The amount of waste increases from year to year and it is expected that global solid waste generation was on pace to increase 70 percent by 2025 to more than 6 million tons per day, or respectively 2,2 billion tons per year. Reasons for this increase are primarily the growth of the global population, increasing urbanization and economic growth. Especially the so called municipal solid waste (MSW) represents a huge problem in many regions of the world today. The waste producers consider the waste as a problem and want to get rid of it. In addition, lack of knowledge about the dangers and a lack of awareness lead to an inappropriate handling and disposal of the waste. Effects of such improper waste disposal are diverse and can affect air pollution, soil and water contamination and negative aspects on health conditions of humans and animals and our climate. For this reason, waste management has become a global issue and a functioning waste management is an important element in achieving key development policy goals.
In general, MSW generation rates and the constitution of the waste are different for developing and developed countries and influenced by economic development, the degree of industrialization, public habits, and local climate. Generally, higher economic development and higher rates of urbanization will result in higher amounts of produced solid wastes. In the European Union, the Directive 2008/98/EC on waste (Waste Framework Directive) sets the basic concepts and definitions related to waste management, such as definitions of waste, recycling, recovery. Waste management hereby refers to the collection, transportation, disposal or in the favorable way the recycling/utilization of waste. The main objective is to avoid waste as much as possible; where avoidance is not possible to recycle it as a resource; and dispose of the residual waste without risk to humans and the environment. Waste thus turns from a problem into a strategic resource. Thanks to strict laws, regulations and a widespread waste management infrastructure in the most European countries, a very high quantity of the collected waste is processed in an environmentally friendly manner. The waste is first sorted according to the available materials, then distributed among different plants that either recycle the particular materials or utilize them energetically. According to the European Waste Framework Directive, the energetic utilization of waste is assigned to the fourth level of the waste hierarchy, below the recycling level. This waste hierarchy gives the highest priority to the prevention of the creation of waste. If the generation of waste is unavoidable, it gives priority in preparing for re-use, recycling and other recovery (such as energy generation) before disposal in landfill sites in descending order of environmental preference. Energy recovery from waste can solve two problems at once: treating nonrecyclable and non-reusable amounts of waste; and generating a significant amount of energy which can be included in the national energy production mix. Energy conversion from waste can be obtained by using different technologies and in the past, the transformation of waste into energy was focused on conventional combustion in waste incineration plants. But there is a much wider range of technologies suitable for energetic waste utilization, e.g. gasification, pyrolysis or the biochemical processes to produce biogas, especially if a sustainable waste management system is implemented and valuable fractions (such as glass, metal, paper, plastic etc.) are separated first for re-use and recycling. The workshop held in Kenitra will focus on the scientific cooperation between the participating university partners from Morocco and Germany in the field of the energetic use of organic waste (in particular the organic fraction of municipal waste after separation of other valuable substances and other organic biomass resources such as agricultural residues) by biogas technologies and the associated requirements for the development of sustainable waste management systems.
In Europe, especially in Germany, municipal waste is often collected separately and used in terms of material and energy. The basic concern is, that the circular economy saves more greenhouse gases than it generates. In contrast, many emerging and developing economies face the major challenge of developing an adequate waste management system that complies with the basic principle of the circular economy and/or improving existing but inadequate and unsustainable waste management systems. In Morocco, for example, increasing waste volumes and their negative effects are causing increasing problems for the environment, drinking water quality and health. About 60% of the population lives in urban areas and especially the population in the sprawling suburbs is affected by the negative environmental and health consequences of inadequate waste management systems. In opposite to Germany, the MSW in Morocco contains a high organic fraction (approx. 70%, compared to 30% in Europe), the waste is not pre-sorted and usually transported to a landfill site, where it is disposed and left to decompose without further treatment. The open decomposition emits bad odors and causes leachate and methane gas to escape uncontrolledly into the soil or the atmosphere, resulting in environmental and health problems. In rural areas, or areas not covered by the waste collection services, the waste is often openly incinerated. This causes the release of toxic substances into the atmosphere and into the soil, resulting in major health and environmental risks and damages. It is obvious that both the landfilling and open field burning are no viable solutions for the existing waste problem.
Meanwhile Morocco looks at waste as a resource which can be better managed to fuel the economy and reduce environmental impacts. Morocco introduced a national solid waste program in 2007 and over a period of 15 years, the program aims to reduce the waste problem by increasing recycling to up to 20%, expanding the local waste collecting services to up to 100% in urban areas, and regulating the large number of illegal dumps. The initiative to increase the rate of recycled material to 20 percent and to improve the conditions of wastepickers is supported by the World Bank. A first step to reduce the waste related problems might be the investment in the Oum Azza landfill site, which is called “the Maghreb’s largest modern landfill facility”. But it has to noted that the Oum Azza project is only a very initial step to reduce the waste related problems of the country and this project it is still far away from a closed cycle management in the waste sector. The waste hierarchy is the key to the transition to the circular economy as defined in the EU Waste Framework Directive. From the different waste to energy options, processes, such as anaerobic digestion which result in the production of biogas and of a digestate are regarded by EU waste legislation as a recycling operation, having for this reason a higher priority compared to the recovery options such as waste incineration and waste co-incineration. The high proportion of 70% biodegradable waste in Morocco implies, that after separation of the reusable materials, such as glass, metal, paper, plastic etc., the remaining waste share should be treated in digestion plants (biogas installations). On the other hand, the high content of water and the low caloric value of this remaining organic fraction means, that waste incineration with limited energy recovery is regarded as disposal according to the European Commission. It is unquestionable that disposal, in landfills or through incineration with little or no energy recovery, is usually the least favorable option for reducing greenhouse gas (GHG) emissions. Experiences from Germany, where around 12 million tons of biodegradable waste are treated yearly in composting and biogas plants (mainly waste from the bio bin, biodegradable garden and park waste, market waste and other biodegradable waste of diverse origins) can be helpful to support Morocco’s efforts to reduce the waste related problems in the country. International cooperation in R&D, Know-how and technology transfer can play a crucial role in innovation and is a key strategic resource for economic development.
Autor*in
Mirko Barz
Themen in »Proceedings of the joint international workshop on Ecological Sustainable Waste Management – Energetic Utilization of Organic Waste (Biowaste4E)«
Energetische Biomassenutzung Energiewandlung Energy recovery Regenerative Energien fermentation municipal solid waste (MSW) organic waste waste