Turning corncobs from waste into treasure, digging gold out of small waste material

Corncobs that were originally used only for burning fires and cooking are treated as treasures in Yucheng, Shandong. Walking into the townships of Yucheng, signs buying corncobs can be seen everywhere: wet corncobs 200 yuan/ton, dry corncobs 400 yuan/ton.

It is reported that going from corncobs to a processed finished product requires a very complex procedure, mainly including hydrolysis, purification, evaporation, crystallization, centrifugation, drying and more than 30 other processes, and what comes out is a sweetener called “xylitol”. Xylitol can prevent dental caries, does not raise blood sugar levels, and has a certain effect in regulating intestinal flora. Corncobs can also be processed into another kind of sugar——“xylo-oligosaccharide”, which also has the effect of regulating intestinal flora and can be added to beverages and health foods. After xylitol is extracted from corncobs, the corncob residue can be used to extract ethanol as a chemical raw material and fuel; after two extractions, lignin can still be further extracted for power generation or growing mushrooms. The author found that many local farmers grow mushrooms, and choosing waste residue to make mushroom sticks can save 50% of costs, and the quality of the mushrooms grown is also very good. The circular economy chain of corncobs has brought the people of Yucheng more than 10 billion in output value.