Türk Linyitlerinin Çeşitli Biyokütleler ve Atık Manyezit Tozu ile Pulverize Yanma Özelliklerinin Düşey Borulu Fırında İncelenmesi

TÜBİTAK MAG Proje15.10.2018Bu projede, düsey borulu fırın kullanılarak iki adet biyokütle (zeytin kalıntısı ve bademkabugu) ile Türk linyitinin birlikte yakılmasının yanma verimliliginin artırılması ve gerekliverilerin endüstriye saglanması amaçlanmıstır. Partikül büyüklügünün etkisini arastırmak içinyakıtlar farklı boyut aralıklarına ögütülmüstür ve yakıtlar arasındaki etkilesimleri analiz etmekiçin farklı biyokütle / kömür oranlarında mekanik olarak karıstırılmıslardır. Düsey borulu fırındeneyleri yüksek sıcaklık (1000 ºC), yüksek ısıtma hızı (~ 104 ºC s-1) ve kısa kalmasürelerinde (~ 3 s) gerçeklestirilmistir. Deney düzenegi düsey borulu fırın, besleme ünitesi vepartikül toplama ünitesinden olusmaktadır. Yakıt, sırınga pompası kullanılarak düsük kütlebesleme hızında (10 g/saat) fırına püskürkülmüstür. Kül parçacıkları reaksiyon alanınınsonundan kademeli impaktör ve vakum pompası kullanılarak toplanmıstır. Toplananpartiküller impaktörün farklı kademelerinde partikül madde (PM) çaplarına göre (PM2.5,PM2.5-10 ve PM büyüktür 10) kategorize edilmistir. Elde edilen sonuçlar yakıtların ve yakıtkarısımlarının, yanma verimini, yanma kinetiklerini, ve partikül madde konsantrasyon vekarakterizasyonu içermektedir. Büyük parçacıkların yanma verimi aynı kalma sürelerindeküçük parçacıklara kıyasla daha düsük bulunmustur. Küçük parçacıkların yanma verimi ise ~2 s' den daha uzun kalma sürelerinde degisiklik göstermemistir. PM emisyonu büyük ölçüdeyakıtın cinsine ve yakıt karısım ise karısım oranına baglı olmustur. Kullanılan biyokütleler,linyit ile karsılastırıldıgında daha düsük PM2.5 olusumuna neden olmaktadırlar. Yakılanbiyokütlenin boyutundaki artıs PM büyüktür 10 emisyonunda artısa neden olurken PM2.5emisyonunda benzer sonuçlar vermistir. Linyitin tek basına yakılması, biyokütle ile birlikteyakılmasına kıyasla daha düsük PM2.5 emisyonuna neden olmustur. PM2.5 emisyonundagörülen bu düsüs her iki biyokütle- kömür karısımında da gözlenmistir. Hesaplamalıakıskanlar dinamigi (HAD) kullanılarak yapılan analizler, katı yakıt yanmasını etkileyen her birtermo- fiziksel islemin karakterizasyonu ve deneysel çalısma için tamamlayıcı verilersaglamıstır. Deney sonuçları HAD analizleri ile karsılastırılmıstır ve veriler arasında uyumbulunmustur.In this project, it is aimed to provide the necessary data for the industry to increase thecombustion efficiency through co-firing of Turkish lignite with two biomasses (olive residueand almond shell), in a drop tube furnace experimental system. Fuels pre-processed todifferent size ranges to investigate the influence of the particle size, and blended in differentratios of biomass / coal to analyze the interactions between fuels. Tests were performed in adrop tube furnace (DTF) at high temperature (1000 ºC), high heating rate (~104 ºC s-1), andshort residence time (~3 s). The experimental setup consisted of a drop tube furnace, afeeding system, and a collection unit. Fuel was fed into the furnace at a low mass rate of 10g.saat-1 using the syringe pump. Ash particles were collected using a stack impactor and avacuum pump. Particle collection was either total or categorized according to differentparticulate matter (PM) diameters, namely, PM2.5, PM2.5-10, and above PM10 (PM>10).The results obtained included particle burnout, particulate matter concentration andcharacterization, and combustion kinetics. Particle burnout was lower for larger particles(same residence time), and constant for the smallest particles for residence times longerthan ~2 s. PM emission greatly depended on the fuel and blend. Biomass fuels presentedlower values of PM2.5 compared to lignite. Larger biomass particles resulted in similarPM2.5 emissions, and in an increase of PM>10. Co-firing of biomass with lignite resulted inlower PM2.5 emission for either olive residue – lignite or almond shell – lignite blends, ascompared to coal firing. Numerical methods provided an additional characterization of eachthermo-physical process that affects solid fuel combustion, and supplemental data for theexperimental trials. The experimental results were used to validate the numerical models,and a good agreement between the data was found

Development and Analysis of the Novel Hybridization of a Single-Flash Geothermal Power Plant with Biomass Driven sCO2-Steam Rankine Combined Cycle

This study investigates the hybridization scenario of a single-flash geothermal power plant with a biomass-driven sCO2-steam Rankine combined cycle, where a solid local biomass source, olive residue, is used as a fuel. The hybrid power plant is modeled using the simulation software EBSILON®Professional. A topping sCO2 cycle is chosen due to its potential for flexible electricity generation. A synergy between the topping sCO2 and bottoming steam Rankine cycles is achieved by a good temperature match between the coupling heat exchanger, where the waste heat from the topping cycle is utilized in the bottoming cycle. The high-temperature heat addition problem, common in sCO2 cycles, is also eliminated by utilizing the heat in the flue gas in the bottoming cycle. Combined cycle thermal efficiency and a biomass-to-electricity conversion efficiency of 24.9% and 22.4% are achieved, respectively. The corresponding fuel consumption of the hybridized plant is found to be 2.2 kg/s.This research is funded by EU H2020 Project GeoSmart: Technologies for geothermal to enhance competitiveness in smart and flexible operation under Grant Agreement number 818576 website: geosmartproject.eu.Publisher's Versio

Atık manyezit tozu ve çeşitli biyokütlelerin Türk linyitlerinin yanması üzerindeki etkisi

Bu projede Türk linyitinin daha önce araştırılmamış farklı biyokütlelerle (üzüm küspesi, ve badem kabuğu) ve bir endüstri atığı olan atık manyezit tozu ile birlikte deneysel bir sistemde yakılarak yanma veriminin artırılması için gerekli dataların endüstriye sunulması amaçlanmıştır. Kömürün bahsedilen atıklarla karıştırılarak homojen yeni bir yakıt haline gelmesi için melas adı verilen bir şeker pancarı atığı bağlayıcı olarak kullanılacaktır. Bu sayede hem Türk linyitinin kullanılabilirliği artırılacak hem de biyokütle, manyezit tozu ve melas gibi atıklar değerlendirilerek ülke ekonomisine katkıda bulunulacaktır. Bu projede, Türkiye'nin çeşitli yerlerinden elde edilen farklı kimyasal ve fiziksel özelliklere sahip Türk linyitleri ile çeşitli biyokütlelerin (üzüm çubuğu ve badem kabuğu) ve atık manyezit tozunun farklı oranlarda melas yardımı ile karıştırılıp TGA ile yanma karakteristiğinin incelenmesi hedeflenmiştir. Bu bağlamda projenin odak noktası karışımın yanma kimyasal kinetik datasını elde etmek, yanmada farklı karışımların (kömür + melas + biyokütle, kömür + melas + manyezit tozu) gaz emisyonları (SO2, CO, and NOx) oluşumuna etkisini araştırmaktır. Deneysel olarak elde edilen veriler Chemkin-Pro adlı kimyasal kinetik modelleme yazılımı kullanılarak elde edilen verilerle karşılaştırılacaktır. Kömürün bu çalışmadaki atıklarla beraber yanma karakteristiğinin daha iyi anlaşılması halinde kazan ve brülör tasarımlarında değişiklikler yapılabilecektir

PARTICULATE MATTER FORMATION DURING CO-COMBUSTION OF AGRICULTURAL RESIDUES WITH TURKISH LIGNITE USING A DROP TUBE FURNACE

This study investigates the particulate matter formation during combustion of olive residue, almond shell, and Tunçbilek lignite. Selected fuels (olive residue and Tunçbilek lignite) were also co-fired to evaluate the influence on particulate matter emission. Olive residue was ground to different size ranges (< 125 µm and 212–300 µm) to investigate the influence of the particle size and blended in different ratios of biomass / coal to analyse the interactions between fuels. Tests were performed in a drop tube furnace at high temperature (1000 ºC), with a high heating rate (~104 ºC/s), and short residence time (~3 s). Fuel was fed into the furnace at a low mass rate of 10 g/h using a syringe pump. Particulate matter was collected using a 3-stage stack impactor and categorized according to the aerodynamic diameters, PM2.5, PM2.5-10, and PM10. The results obtained included particle burnout, and particulate matter concentration. Particle burnout was above 95% for all studied fuels. Particulate matter emission depended greatly on the fuel and the blend. Olive residue presented the lowest values of PM2.5 (176 mg/g ash in fuel fed) compared with both almond shell (214 mg/g ash in fuel fed) and Tunçbilek lignite (286 mg/g ash in fuel fed). PM10 emission was particularly low for olive residue (~200 mg/g ash in fuel fed), whereas almond shell and Tunçbilek lignite showed similar values (~400 mg/g ash in fuel fed). Larger biomass particles resulted in unchanged particulate matter emissions. Co-firing of the olive residue with the Tunçbilek lignite resulted in lower PM2.5 (as compared to neat olive); higher PM2.5-10 (as compared to neat lignite); and lower PM10 (as compared to lignite). Blends of OR-TL in 25-75 ratio showed lower values of both PM2.5 and PM10 as compared with the 50-50 blends of the same fuels

Influence of biomass thermal pre-treatment on the particulate matter formation during pulverized co-combustion with lignite coal

© 2021 Elsevier LtdThis work investigated the particulate matter formation during co-combustion of thermally pre-treated biomass with coal. Olive residue was chosen as agricultural waste biomass, and Tunçbilek lignite as the coal. The biomass was thermally pretreated to assess the influence of the pretreatment temperature on particulate matter formation during co-combustion. Specifically, the olive residue was torrefied (at 275 °C) and pyrolyzed (at 500 °C) using a tubular oven. The biomass-coal blends in a 50:50 wt% ratio were co-fired in a drop tube furnace operated at 1200 °C, heating rate of ∼ 104 °C/s, residence time of ∼ 3 s, and dry air atmospheric conditions. The particulate matter was collected at the bottom of the reactor using a three-stage stack impactor which allowed to quantify the relevant levels of PM2.5, PM2.5-10, and PM10. The results showed that co-combustion resulted in clear reduction of PM2.5 emission to values close to those of the biomass fuel. Specifically, combustion of blends of Tunçbilek lignite with olive residue, torrefied olive residue, and olive residue char resulted in 646, 408, and 559 mg/MJ input, respectively. Moreover, the mechanisms responsible for the formation of PM2.5 during biomass and coal combustion were found applicable to biomass-coal blends. The shift from fine to coarser particles with co-firing is likely to allow the capture of PM from biomass-coal co-firing by conventional coal-PM traps in existing coal power plants

Combustion Behavior and Kinetics of Turkish Lignite Blended with Biomass/Magnesite Dust

The effect of blending on the combustion behavior of a Turkish lignite blended with biomass or magnesite dust using a thermogravimetric analyzer (TGA) coupled with a Fourier transform infrared spectrometer (FTIR) under air atmosphere has been investigated. The lignite used in this study is Tuncbilek lignite (TL), which is blended with two biomasses, olive residue (OR) and almond shell (AS), and the inorganic industrial waste, magnesite dust (MD). The blends are composed of various weight fractions of fuels, with a constant weight fraction of molasses (10% by weight) as a binding agent. TGA weight loss trends are used to obtain characteristic temperatures and to define weight conversion stages. Experimental results show three distinct stages of conversion during combustion of biomass fuels and two stages for lignite. Burnout temperature increases and the combustibility index decreases for lignite when blended with molasses. On the other hand, blending of biomass with lignite results in approximately 40 degrees C lower ignition temperatures and an increase in combustibility index and reactivity. FTIR results of biomass blend combustion indicate a positive effect in reducing the CO and SOx emissions when blended with lignite. Magnesite dust addition causes a decrease in gaseous emissions for all blending ratios having the maximum reduction at 10% by weight of magnesite. Moreover, kinetic parameters (apparent activation energy, pre-exponential factor) for each fuel are obtained using a model-fitting method (Coats-Redfern). Addition of biomass/magnesite dust to the lignite caused a decrease in apparent activation energy. Specifically, apparent activation energy of lignite decreases from 105.6 to 81.6 kJ.mol(-1) by adding molasses and reaches approximately 20 kJ.mol(-1) by adding 70% by weight of olive residue and almond shell, respectively. (C) 2018 American Society of Civil Engineers