Talk:B2-Environmental problem targeted

Environmental problem targeted

Explain why you consider that this problem is related to European environmental policy and legislation.

State of the art and innovative aspects of the project

(No information needs to be provided in this box for projects on forest monitoring. Applicants for such projects should indicate 'NON APPLICABLE').

Provide a description of the state of the art of the technique or method addressed. Elaborate on the technical description of the processes or methods and/or proposed innovation(s), new elements, improvements. Describe the previous research and experience carried out in preparation for the project implementation, including feasibility studies. Please take into account that the innovative nature of the proposed actions can be evaluated from different perspectives: a) relative to the technologies applied by the project (technological innovation), b) relative to the way technologies are implemented (innovation in processes or methods) and, c) concerning the business and economic models developed by the project (economic and business innovation). These different dimensions of the innovatory nature have to be compared with the state of the art at global (world) level. N.B. Geographical technology or practice transfer alone (without a genuine development of innovative character) can not be considered as innovative. Equally, projects which involve pure research and development or merely preparatory activities (studies, surveys, etc) can not be considered innovative per se.

Overall picture

Due to rapid increases in urban population, sewage sludge and municipal solid waste (MSW) have increased dramatically in the past two decades. Lu et al. (2009) reported that environmental pollution caused by sewage sludge and MSW has become a serious social problem that prevents urban development, especially for large cities in developing countries. It is also stated that it is critical to find ways to effectively reuse such wastes and decrease their influence on the environment. Fricke et al. (2005) reported that conventional waste disposal has already met its limits throughout most of the world with increasing waste generation and rising proportions of packaging and toxic compounds in MSW. Moreover, landfilling of waste leads to pollutant emissions over long periods of time and requires sophisticated emission control and treatment methods. The consequences are long after-care periods for abandoned landfills. Furthermore, in many countries it is increasingly more difficult to find suitable locations for landfills which are accepted by the population. These circumstances are to be found all over the world and make new strategies for waste management necessary. The promotion of waste minimisation and recycling are important components of modern waste management strategies. The most common and cost-effective method has been reported as anaerobic digestion. The yields of anaerobic digestion process for the treatment of 100 kg of OFMSW was reported to be 35 kg compostable fraction with 22 and 44 KWh electricity and heat energy, respectively (Mata-Alvarez, 2002). Kayhanian and Hardy (1994) reported that anaerobic digestion of biodegradable organic fraction of MSW has the benefit of significant reduction in the volume that material would occupy in a well compacted landfill. It was also reported that the mass lost in this reduction is converted to a biogas with a clean burning quality and medium thermal energy value. On the other hand, anaerobic co-digestion of the organic fraction of municipal solid waste (OFMSW) and sewage sludge is a sustainable and an appropriate treatment alternative due to bioenergy and nutrient recovery while combining the treatment of two largest municipal waste streams. By co-digestion, volume of the organic wastes is reduced and stabilized, a residue that can be used for soil conditioning is produced, and energy in the form of methane is recovered (Hartmann et al., 2002). Sludge occurring at municipal wastewater treatment plants (WWTP) is considered as one of the most appropriate co-substrates for co-digestion with the OFMSW. With the large amount of sewage sludge produced in WWTPs and the large number of existing anaerobic digesters to stabilize it, the anaerobic co-digestion of OFMSW with sewage sludge is especially attractive (Hamzawi et al., 1998). Moreover, considering the different substrate characteristics, content of macro- and micronutrients are high in sewage sludge whereas it is low in OFMSW. Besides, C:N ratio and contents of biodegradable organic matter and dry matter are low in sewage sludge, however they are high in OFMSW. Thus, co-digestion of OFMSW together with sewage sludge is beneficial due to a number of substrate characteristics of both waste types that are complementary in their combination. Krupp et al. (2005) reported that co- fermentation of biowastes in WWTP may affect plant operational performance in terms of degree of degradation, gas production, drainability, and backload. Sosnowski et al. (2003) also reported that dilution of potential toxic compounds, improved balance of nutrients, and synergistic effect of microorganisms are the other benefits of co-digestion including hygienic stabilization if process is operated under thermophilic conditions. Since conventional MSW management has been primarily disposal by landfilling in the developing countries like Turkey,