Composition of the liquid product by pyrolysis of dried distiller's grains with solubles

Presently, dried distiller's grains with solubles (DDGS) are mainly used as the livestock feed. However, the high fiber content in DDGS limits its use as the diet for animals. Therefore, with increasing production of DDGS in recent years, it is desirable to find some new uses of DDGS for fuels and/or for high value chemicals. In this paper, experiments on pyrolysis of DDGS by spouted-entrained bed and by fixed bed are carried out, and the pyrolytic liquids are analyzed by GC/MS. It was found that the composition of the liquid by pyrolysis of DDGS in 490–570 °C by spouted-entrained bed is rather complex, and varies with pyrolytic temperature. However, the pyrolysis of DDGS material is not quite suitable to the process by spouted-entrained bed, due to a severe clogging problem inside the reactor. By fixed bed, the composition of the oil phase of the liquid obtained in 490–610 °C is much simpler, mainly phenol derivatives, fatty acids and their esters. When pyrolyzed at 570 °C with catalyst of CaO, aliphatic and aromatic hydrocarbons are generated more, while fatty acids and their esters are much reduced.

► Compositions of the liquid products from pyrolysis of DDGS were analyzed by GC/MS. ► Components in pyrolytic liquid by spouted-entrained bed are rather complex. ► Oil phase by fixed-bed is simpler as phenols, fatty acids and their esters. ► Spouted-entrained bed is not proper for frequently clogging problem. ► Aliphatic and aromatic hydrocarbons are more generated under catalysis of CaO.