Even though corn or maize is not one of the most economic crops in Thailand, there has been an increasing utilization of corn cob in power generation and solid fuel in order to achieve zero-waste philosophy in corn processing industry. The figure below shows the 2006 production of maize around the world, where USA is accounted for almost half of the world
production and also with the highest yield in the world. Although China has a similar amount of land for maize plantation to USA, the lower yield in China makes its production only half of the USA figure.

Fig. 2.17.4. World leading countries in maize
production in 2006.

For the past 10 years in Thailand, the yield has been gradually increasing but not fast enough to compensate the decreasing plantation land, resulting in a decreasing maize production, as shown in Fig. 2.17.6. In 2006, the yield is 411 g/m2 (4.11 t/ha) averaged over whole 9,000 km2 (0.9 million ha) harvested area. Most of maize production in Thailand goes to food and feed industry; both of which corn cob is left as solid waste in the plants. In 2006, 33 Gg (0.33 Mt) of corn cob is reported, where 200 Gg (0.2 Mt) comes from the lower North part in Thailand especially Phetchabun (76 Gg (0.076 Mt)), Tak (35 Gg (0.035 Mt)) and Nakorn-sawan (33 Gg (0.033 Mt)). This corn cob is usually dried before putting in the boiler to generate steam for power generation, e. g. 10 MW power generation unit in the ethanol plant Pornvilai International Group Co.

Another value-added product for corn cob is corn charcoal, where corn cob is first heated to about 900-1000oC before being palletized with proper binder. Then, the final drying at 120oC for 12 h is conducted to obtain charcoal with less than 5% moisture.