Kentsel atık depolama sahalarına giden biyobozunur atıkların azaltılmasının Türkiye'deki çöp gazı (LFG) potansiyeline olan etkileri

As part of European Union acquis adaptation process, Turkey's waste management systems along with other important areas got in a fast change and development period. With the issuance of The Regulation of Sanitary Landfilling of Waste in 2010, the procedure for landfilling waste was defined, certain terms were put to motion for rehabilitation of disorderly waste dump-sites and necessary precautions were taken to prevent formation of any future disorderly waste dumping activities. These developments introduced vast changes, the disorderly waste disposal sites that reached to almost 2000 in 2009, were swiftly shut down; along with fast introduction of proper waste disposal sites, which processed ever-growing amount of urban wastes. In scope of related regulations, the landfill gas produced at the waste disposal sites was required by law to be collected and burned; and used for renewable energy in the power plants if it is financially feasible. In 2010, with the introduction of Turkish Ministry of Energy and Natural Resources' program to support renewable energy, 10 years of fixed priced purchase by the government was guaranteed for the power produced by other renewable resources as well as landfill gas and therefore production of energy with the usage of landfill gas was given incentive from the government. In keeping with acquired experience in the field, the power plants that produce energy with landfill gas that have 1 MW and more of installed capacity became financially feasible with the given incentives. In other words, it became possible to have landfill gas to electricity plants at the sites that produce approximately 500 m3/hour of landfill gas or sites that serve cities with 750,000 populations in consideration with the country's current urban waste characterization and waste produced per capita. However by scope of the Regulation of Sanitary Landfilling serious goals are set for diversion of biodegradable waste sent to landfills. According to this, biodegradable wastes that sent to landfills will be decreased at 3 stages and finally in 2025, %35 of the biodegradable wastes would be sent to landfills compared to total production biodegradable wastes it 2005. However, a decrease in biodegradable materials going to landfill sites may influence the amount of landfill gas for future years and the feasibilities may become negative which will end up with many problems like shutting down the plants which are on operation due to the financial stress of operators. The purpose of this thesis is to see the effects of biodegradable waste diversion from the landfills on Turkey's future landfill gas potential. For that purpose, first of all, current situation in MSW waste and LFG management has been evaluated. Three different scenarios are evaluated in this study in order to see the effects of biodegradable waste diversion on landfill gas production potential. The first scenario is the baseline scenario that no diversion is considered, the second scenario is the full consistence to the regulations scenario and the third one is the consistence to the regulations with a five years lag scenario. First, annual waste amounts that sent in landfills in Turkey and its characteristics were determined. Country population and waste disposal amounts come up by TUIK data, and missing data of some years derived by graphical method. For determination of waste characterization, data from Solid Waste Master Plan's final report is used. At SWMP report country divided into different regions and waste characteristics of every different area. Aforementioned waste characteristics data is critically important. Data derived 2003-2040 but region's population comparatively taken weighted mean produces different region characteristics. For determination of landfill gas amount "Central-Eastern Europe Landfill Gas Model Version 0.1" was used in this study The most important factor that selection of this model is the parameters, which based on are compatible with Middle-east countries waste characteristics and commonly usage of this model. Previously created material classification of Turkey's average waste characteristics obtained by urban mixed characterization of SWMP. Because of this, transformation and derivation of acquired different data of waste characterization at first stage used for model input. For example, at SWMP paper, cardboard and high volume cardboards categorized differently but at the model this materials gathered in one and named as "paper and cardboard". Waste characterization and total amount of waste going to landfill site was determined for each scenario for the years between 2003-2040. According to the principle of this model, a calculations are run linked with a series of following years' total waste amount together with a single waste characteristics in accordance with data formulization. For that reason the model was run for 38 times for each scenario which means that 114 times total. As an example for Scenario 1; the waste characterization of 2003 was entered to the model and "output table for 2003" was formed for 100 years between 2003 – 2102. Then, the waste characterization of 2004 was entered to the model and "output table for 2004" was formed and same process was repeated with each years' data till 2040 and 38 output table was generated. In the next step, the results of each output table was used and average LFG production amount for each year was calculated in accordance with the general formula which is formed.The same method was applied for all scenarios and potential landfill gas amounts in between 2003 – 2102 was determined. The installed LFGTE plant capacity of Turkey is approximately 180 MWe in 2015. Most of the plants use 80% of their installed capacities in whole year and keeps reserve capacity. Therefore, actual electricity from LFGTE plants in Turkey is approximately 144 MWh. It's seen in the results that, Turkey's LFGTE generation potential in 2016 is 205 MW. This means that around 70% of total LFGTE generation potential of Turkey is being used at the end of 2015. As main result, landfill gas potential in 2040 will be the half of the situation that no biodegradable waste diversion done if it's obeyed to the legislation provisions. It's possible to recover 73% of landfill gas in average conditions. It's calculated that the maximum potential electricity generation in LFGTE plants will be 376 MWh in 2040 if there is no biodegradable diversion. However it may decrease up to 187 MWh if diversion applied properly. Even if 5 years of delay seen on the application of biodegradable waste diversion, there will be approximately 30,000 m3/h more LFG production potential in 2023 in comparison with the full adaptation case, which means that 21,900 m3/h more LFG can be collected or 36 MWh more electricity can be generated. In other words, if 5 years of lag seen on the application, LFGTE generation potential of Turkey increases 15 % in 2023. It should be kept in mind that 36 MW plant can serve electricity energy for one million persons' living purposes. Biodegradable waste diversion will cause dramatic decrease on LFG recovery in accordance with the decrease of LFG potential in Turkey. However, it may also create some great opportunities if diverted organics to be handled properly. It's crucial to manage diverted organics in order to get maximum benefit. The gap which is going to be occur in LFGTE plants' electricity generation potential with the decrease of LFG can be closed by recovering the potential energy of diverted organics in anaerobic digesters, co-digesters or in other (thermal) organics recovery plants. It's certain that the degradation period in landfills takes long years which gives us the opportunity to recover its potential in a long time. However, a lot more energy can be recovered from the same amount of biodegradable material in a shorter time in closed reactors. At that point, the consequence of the residues of these anaerobic digesters must be thought on. As a brief conclusion, diversion of biodegradables will cause dramatic decrease in Turkey's cumulative landfill gas potential in future, which will especially influence the further investments on LFG recovery projects. Therefore, alternative biodegradable material recovery technologies should be developed in order to fill the gap which will occur with the decrease on LFG.