Thermal-Catalytic Conversion of High Moisture Spent Grains to a Gaseous Fuel

Hiroyuki Okamoto, Y. Kitagawa, T.Minowa and T. Ogi. Poster presented at the MBAA 111th Anniversary Convention, Minneapolis, Minnesota, September, 1998.

Abstract
Asahi Breweries recycles spent grains as cattle feed, however, increased beer production has resulted in an increase in spent grains. We have investigated the possibility of direct conversion of spent grains to gas to deal with this surplus. A batch-type laboratory scale reactor (Volume 100 ml) was used to convert the high-moisture spent grain (77.4% moisture) to gas products of composition: carbon dioxide (49%-50%), methane (33%) and hydrogen (14%). A nickel catalyst was utilized at 623K and 18Mpa. The gas yield was approximately 85% on a carbon basis. Little residue remained after the reaction. Dilute waste-water was also generated by this process. The load of this waste-water was 3g-TOC - 12 g-TOC per 1Kg of spent grain (dry weight). TOC removal reached 89.5%. The conversion of spent grains to gas is thus a good means of producing energy with few adverse environmental effects. The gas produced will be used as a fuel cell energy source. We forecast that catalytic gasification of spent grain for energy use will become a promising method of treating spent grain.
Keywords: spent grains, thermal catalytic conversion, energy  

Sintesis
La Cerveceria Asahi recicla el afrecho, como alimento para ganado, sinembargo, un incremento en la produccion de cerveza ha resultado en un incremento del afrecho, Hemos investigado la posibilidad de la conversion directa de afrecho a gas para manejar este excedente. Un reactor por lotes de tamaflo de laboratoric, (Volumen 100m1) fue utilizado para convertir at afrecho de alto contenido de humedad (77.4% de humedad) a productos de gas de composicion dioxido de carbono (49%-50%), metano (33%) c hidrogeno (14%). Un catalista de niquel fue utilizado a 623K y 18Mpza. EI rendimiento del gas due aproximadamente 85% en base a carbon. Poco residuo quedo despues de la reaccion. Tambien se genero agua servida diluida en este proceso. La carga de estas aguas servidas fue de 3 g-TOC - 12 g-TOC por 1Kg de afrecho, (peso en seco). La remocion de TOC alcanzo 89.5%. La conversion de afrecho a gas es por lo tanto una buena manera de producir energia con pocos efectos adversos para el medio ambiente. El gas producido sera usado como una celda de fuente de energia. Pronosticamos que la gasificacion catalitica del afrecho para uso energetico se convertira en un metodo prometedor para tratar el afrecho.