E. Duyuşen GÜVEN Department of Environmental Engineering Dokuz Eylul University, Izmir, Turkley

E. Duyuşen GÜVEN Department of Environmental Engineering Dokuz Eylul University, Izmir, Turkley

The current study aims to present and compare the results of different composition and charac-terization studies conducted for the city of Izmir. Time period between 1996 and 2015. The data obtained from the previous academic works and municipality studies.

Environmental Law (no:2872) regulated in 1983 Solid Wastes Control Regulation (1991) Regulation on Waste Management ( 2015) Regulation on Sanitary Landfilling (2010) Packaging Wastes Control Regulation (2005) The Compost Announcement (2015) The Biodegradable Wastes Regulation ( draft form) Originated from EU Directives, in time, a number of legislations were also regulated for specific waste streams in Turkey.

Turkey; - 79 million capita - 7 geographical regions - The to-tal number of municipalities - 1396 and all of them give municipal waste ser-vices. - Total amount of municipal waste in Turkey in 2014-28 million tones and the amount of municipal solid waste per capita is 1.08 kg/day Landfilling is still the main waste disposal method in Turkey. Nearly 63% of the waste goes to contolled landfill sites, 35% is disposed in the municipalities uncontrolled dumping 2% waste is disposed via other methods such as composting, burial and some other crude ways.

Third largest metropolitan city ; area - 12.007 km 2 population 4.2 million Located on the western Anatolia on the Aegean Coast, surrounded by the Aegean Sea. 91.4% of the population lives in the urban areas 8.6% lives in the rural districts such as villages or townships According to the 2015 data, the rate of net migration is %5. Economy is comprised of industries, commerce, transportation-communications, and agricultural activities to a great extent. Urbanization percentage, literacy percentage, gross domestic product per capita and ratio of those employed in industry is high İzmir has a huge and dynamic tourism potential due to its geographical position, diversity of its historical and cultural resources, geographical features and its infrastructure for tourism Izmir has a typical Mediterranean climate - the total precipitation for Izmir averages 690 mm per year; however, 78% of that falls during November through March (TSMS, 2011).

Izmir Metropolitan Municipality (IMM) is responsible for the whole city including 30 districts, By the year 2014, 1,304,876 tones of municipal solid waste is collected and disposed by the IMM Currently, Harmandalı Solid Waste Landfill Area which has been operated since 1992 and almost completed its capacity, is accepting most of the municipal industrial, and medical wastes generated in Izmir In addition, Bergama Sanitary Landfill Area also accepts solid waste generated in Izmir. An Integrated Mechanical Biological Processing Plant has been designed by the IMM which covers recycling and recovery units, anaerobic processing, composting, and sanitary landfilling units. But still, legal processes for the site selection of this integrated plant has not been completed.

In 1996, a study by DEU with the support of IMM. Solid waste samples were collected in three consecutive seasons. Domestic solid wastes were collected from high income level (HIL), medium-income level (MIL), and low income separately. No composition determination were done and all the wastes were han-dled as mixed collection for this study. A total of 180 samples were used in this work. In 2005, another study was performed in DEU as an individual project. Three central re-gions namely Güzelyali, Gaziemir, and Buca were selected for sampling. In every region, two districts of each income group was were chosen for sample collection. By this way, domestic solid wastes of 18 districts were sampled in Izmir city for 14 days. Sampling areas for the studies 2005 and 2014 In 2014, another individual study was performed in DEU. Sampling has been conducted by taking solid wastes from three districts of each county Karşıyaka, Bornova and Konak with respect to incomes of residents. Three consecutive days of sampling colllected by county municipalities were brought to the laboratory for this study. The composition and characterization works were done for each district.

2005 2014 HIL Biodegradables, % 56.6 65.1 Recyclables, % 36.9 25.6 Other, % 6.5 9.4 MIL Biodegradables, % 60.9 57.6 Recyclables, % 23.2 33.4 Other, % 15.9 9.0 LIL Biodegradables, % 40.3 65.4 Recyclables, % 20.0 29.7 Other, % 39.7 4.8 The domestic solid wastes were separated as biodegradables, recyclables, and other wastes in the 2005 and 2014 studies. The average values for each income level areas were calculated and presented. There is a significant decrease in the recyclables for the high income level areas. Separate collection of domestic solid wastes is not prevalent in the city and as a result, there is an increase in the scavenging activities, and most of them are employed by the scrap companies, recently. The decrease in the recyclables may be because of the increase in the scavenging activities which are dominant in the high income districts.

For the middle income level areas, the ratio of recyclables increase in these areas. This can be explained by the high migration rate of Izmir (5% lately), and most of the immigrants settle in the middle and low income level areas. Depending on the extension of population in these areas, the amount of recyclables which is an indicator of high population, also increase. For the low income level areas, a significant change is observed for the other type of wastes which include trashes, unusable stuff and mainly ash residues. In Izmir, the use of natural gas started in 2002 for the industrial areas and in 2007 for the houses At current, most of the city is surrounded by natural gas distribution pipelines, even the low income level districts. Also the use of electric heaters have been common in the city recently. The high amount of other wastes deter-mined in LIL in 2005, depends on the use of wood-coal burning stoves that produce high amounts of ash.

1996 2005 2014 Water content, % HIL 62.3 80 60 Organic matter content, % MIL 60 74 67 LIL 56 81 65 HIL 71 88 63 MIL 58 82 67 LIL 49 89 67 The solid wastes were analyzed for their water content, organic matter content, calorific value, and total organic carbon concentrations. In the earliest study (1996), there was no separation of recyclables and other wastes and the analyses were conducted for the bulk samples. For the studies conducted in 2005 and 2014, recyclables were separated from the waste mass, and the remaining part was analyzed. Mixed collection in 1996 is the reason for the lower water content when compared with 2005 results. Water content once again decreases in 2014 for all the areas. This can be explained by the increasing use of packaged food which produces less fruit-vegetable peelings. There is also a decrease in the organic matter content, this reason is the same with the water content decrease.

Calorific value, kcal/kg Total organic carbon, %dry weight 1996 2005 2014 MIL 3040 3036 3322 LIL 3227 3200 3252 HIL 14.0 29.5 MIL 14.5 35.9 LIL 10.4 34.9 For the calorific value (low heat value), there is not much change in the years and no significant changes in the income level areas. The values are around 3000-3500 kcal/kg which is suitable for further investigations of RDF production. But yet, incineration will not be feasible for the solid wastes of Izmir depending on the high water content. On the other hand, there is a significant change in the total organic carbon content of the wastes in 2014, especially for the middle and low income level areas. This situation makes the waste appropriate for anaerobic digestion prior to methane production.

The fluctuations in the solid waste characteristics and composition of domestic solid wastes of Izmir are presented in the content of this study. It is clear that solid wastes of Izmir are mainly composed of biodegradables which include kitchen wastes, garden trim-mings, etc. On the other hand, more than 60% of the waste is the water content which makes the waste inappropriate for incineration process. High organic content and total organic carbon concentration should be considered, since these values are proper for the microbial activity to produce methane. The variations in the sampling districts and areas can also be the reason of the differences as well as other factors described above. It is for sure that characterization studies for the domestic solid wastes of Izmir should be maintained permanently to keep the contemporary data.