ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Tar content and composition during a low-temperature steam gasification of rice husks

Van Minh Duong, Monika Seiber, and Hermann Hofbauer

University of Chemistry and Technology Prague, Prague 6 Dejvice, Czech Republic

E-mail: Duong.Van.Minh@vscht.cz

Received: 20 April 2019  Accepted: 9 October 2019

Abstract:

The research work extends our recent empirical knowledge on the rice husks, a carbonaceous solid material. This solid biofuel option was characterized with a potential net heating value of 16–17 MJ/kg, significant high ash deformation temperature recorded above 1450 °C, capable and considerable for thermochemical conversion systems. An experimental performance on a dual fluidized bed steam gasifier using rice husks pellets was carried out at a low temperature between 600 and 650 °C and fuel power of 100 kW_th. Pure steam was used as a gasification agent in fluidization at a steam to fuel ratio of 1.2 kg/kg on dry basis. Calcite with mainly CaCO₃ in composition was used as bed material for the reactor. Tar content and composition in the product gas stream were analyzed with a gas chromatograph coupled with mass spectrometer (GC–MS). Significant high amounts of total GC–MS tar components (without benzene, ethylbenzene, and xylene) and gravimetric tar (higher molecular tar) were detected at 29.44 and 17.82 g/m³ on dry basis. Benzene content was, respectively, presented on a value of 9 g/m³ on dry basis. Obtained products consisted of relevant amount of phenol and heterocyclic aromatic tars (class 2). The specific composition of common and additional analytes presented in GS–MS tar was summarized for better understanding of tar formation and reduction phenomena of rice husk gasification.

Keywords: Solid biofuel; Rice husks; Steam gasification; GC–MS tar

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-019-00952-1

Chemical Papers 74 (4) 1123–1131 (2020)