Valorization of horse manure through catalytic supercritical water gasification
WASTE MANAGEMENT, cilt.52, ss.147-158, 2016 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 52
- Basım Tarihi: 2016
- Doi Numarası: 10.1016/j.wasman.2016.03.049
- Dergi Adı: WASTE MANAGEMENT
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Sayfa Sayıları: ss.147-158
- Orta Doğu Teknik Üniversitesi Adresli: Hayır
Özet
The organic wastes such as lignocellulosic biomass, municipal solid waste, sewage sludge and livestock manure have attracted attention as alternative sources of energy. Cattle manure, a waste generated in surplus amounts from the feedlot, has always been a chief environmental concern. This study is focused on identifying the candidacy of horse manure as a next generation feedstock for biofuel production through supercritical water gasification. The horse manure was gasified in supercritical water to examine the effects of temperature (400-600 degrees C), biomass-to-water ratio (1:5 and 1:10) and reaction time (15-45 min) at a pressure range of 23-25 MPa. The horse manure and resulting biochar were characterized through carbon-hydrogen-nitrogen-sulfur (CHNS), inductively coupled plasma-mass spectrometry (ICP-MS), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy and scanning electron microscopy (SEM). The effects of alkali catalysts such as NaOH, Na2CO3 and K2CO3 at variable concentrations (1-2 wt%) were investigated to maximize the hydrogen yields. Supercritical water gasification of horse manure with 2 wt% Na2CO3 at 600 degrees C and 1:10 biomass to-water ratio for 45 min revealed maximum hydrogen yields (5.31 mmol/g), total gas yields (20.8 mmol/g) with greater carbon conversion efficiency (43.1%) and enhanced lower heating value of gas products (2920 kJ/Nm(3)). The manure-derived biochars generated at temperatures higher than 500 degrees C also demonstrated higher thermal stability (weight loss <34%) and larger carbon content (>70 wt%) suggesting their application in enhancing soil fertility and carbon sequestration. The results propose that supercritical water gasification could be a proficient remediation technology for horse manure to generate hydrogen-rich gas products. (C) 2016 Elsevier Ltd. All rights reserved.