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Agricultural biomass has some drawbacks such as high moisture content, low energy density and wide distribution and as a result, the cost of transport and storage are high. Moreover, raw biomass has poor grindability so its use in a pulverized boiler or entrained flow gasifier is difficult. Torrefaction is a mild pyrolysis process carried out at temperatures ranging from 200°C to 300°C to deal with these problems. The cotton stalk and wheat straw were torrefied in a fix-bed reactor at moderate temperatures (200°C, 230°C, 250°C, 270°C and 300°C) under N 2 for 30 min. The biomass chars after torrefaction had higher energy density and improved grindability characteristics compared with raw biomass and they also showed hydrophobic characteristics. The volatiles consist of a condensable fraction and a non-condensable fraction. The former mainly contained water and tar (organic products but mainly acetic acid). The non-condensable products are typically comprised of CO 2 , CO and a small amount of CH 4 and even trace H 2 . The volatiles increased with an increase in the torrefaction temperature but the solid yield and the energy yield decreased. However, the grindability and energy density of the biomass char showed great improvement. A kinetic study on the generation of the main non-condensable gases was undertaken and we conclude that the gases are formed by parallel independent first-order reactions. Characteristic kinetic parameters for the generation of each gas were determined.

In view of existing situation of Green Supply Chain (GSC) and the control issues of coordinate management with large scale systems for GSC, the control channels of large scale systems for coordinate development of GSC are discussed by applying the theory and method of large scale systems based on large system cybernetics. The theoretical basis and available means for the scientific design and effective application of GSC management are provided by establishing relevant mathematical models. It is a vital technology for promoting GSC management.

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W-flame combustion technology was developed for ignition and burn out of the coals with low volatile. Numerical simulation was carried out for the combustion process of a W flame boiler in certain 600MW power station. Using steam temperature inside the waterwall and thermal resistance of the waterwall as the thermal boundary conditions, simulation was completed based on the commercial software platform FLUENT. The results show that the heat flux of the waterwall below furnace arch varies little under different loads, and NOx formation in W-flame boiler is relative high at various loads. Besides, since the flame center moves upwards in the furnace in practical operation of W-flame boiler, condition opposite to the normal regularity occurs, namely NOx formation increase with the ratio of the overfire air.

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