Babak KEIVANI, Hayati OLGUN, Aysel T. ATİMTAY

Biyokömür-Soma Kömür Karışımlarının Oksiyanma Koşullarında Birlikte Yakılmasının Deneysel İncelenmesi ve Emisyonlar Üzerindeki Etkileri

Bu deneysel çalışma, kızılçam talaşından elde edilen biyokömürün Soma linyit ile birlikte yakılmasını kapsamaktadır. Deneyler 30 kW termal kapasiteli dolaşımlı akışkan yataklı yakma (DAY) sisteminde, havada ve oksijence zengin hava ortamında gerçekleşmiştir. Deneylerde akışkan yatağın içindeki yanma sıcaklığı 850 + 50 °C’de tutulmuştur. Farklı oranlarda linyit ve biyokömür karışımları oksijence zengin ortamda yanma testleri yapılmıştır Kızılçam talaşı için 300 °C ve 30 dakika işlem koşullarının soma linyit ile biyokömürün akışkan yatakta birlikte yakılması açısından en uygun üretim koşulları olacağı görüşüne varılmıştır. Linyitteki biyokömür karışımın payı %50’ye kadar artırılmıştır. Yakıt karışımlarının ağırlıkça %50’ye kadar çıktığı ve sistemde biyokömürün etkin bir şekilde yakıldı bulunmuştur. Sonuçlar kömür ve biyokömürün birlikte yanması için biyokömürün iyi bir katkı yakıtı olabileceğini göstermektedir. Ayrıca oksijence zengin ortamında birlikte yakmanın SO2, CO ve N2O’nun baca gazı emisyonlarını azaltmak için bir seçenek olduğunu göstermiştir. Havaya oksijen eklenmesi yanma verimini arttırmış ve CO emisyonlarını azaltmıştır. Biyokömürün içinde kükürt bulunmadığından SO2 emisyonlarını önemli ölçüde azaltmıştır. Bununla birlikte, NOx emisyonları, yüksek oksijen konsantrasyonları ve yüksek seviyelerde biyokömür ilavesi ile artmıştır.

Anahtar Kelimeler:

Oksijence zengin ortamda yanma, biyokömürleştirme, emisyonlar, biyokömür

Experimental Investigation of Co-combustion of Biocoal with Soma Lignite in Air and The Oxygen-enriched Air Atmospheres and Its Effects on Emissions

This experimental work includes the co-combustion of Soma lignite with biochar obtained from red pine sawdust. The experiments were carried out in a circulating fluidized bed combustion (DAY) system with a thermal capacity of 30 kW, in air and in an oxygen-rich air atmosphere. In this study, the combustion temperature in the fluidized bed was kept at 850 + 50 °C. Combustion tests of Soma lignite and biochar mixtures at different rates were carried out in an oxygen-rich medium. It was concluded that 300 °C and 30 minutes processing conditions for red pine sawdust would be the most suitable production conditions for the co-combustion of soma lignite and biochar in a fluidized. The share of biochar mixture in lignite has been increased up to 50%. by weight. It was found that the biochar was burned effectively when the mixture of biochar was up to 50%. The obtained results emphasized that biochar can be a good additive fuel for co-combustion of coal and biochar. It has also shown that co-combustion in an oxygen-rich atmosphere is a choice to decrease stack emissions of SO2, CO and N2O. Addition of oxygen to air increased the combustion efficiency and reduced CO emissions. Since biocoal does not have sulfur in it significantly reduced SO2 emissions. However, emissions of NOx increased with high oxygen concentrations and high levels of biocoal addition.

Keywords:

Oxygen enriched combustion, torrefaction, emissions, biocoal Oxygen enriched combustion, torrefaction, emissions, biocoal,

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