Wood logistics

Wood was the easiest fuel to use in early steam locomotives, but it was soon realized that the logistics of wood fuel were limiting. Steam engines were developed that could burn coal, peat, or (later) oil where those fuels were more abundant. For intercity railroads (especially in the Americas, Asia, Australia, and Africa), coal remained the fuel of choice for one hundred years. Despite impressive technology development, steam locomotives never could achieve thermal efficiencies greater than about 6 to 8 percent. 

John V. Venegoni, VP/Gen. Mgr.-Surfactants Robert J. Wood, VP/Gen. Mgr.-Polymers Anthony Martin, VP-Europe Debra A. Stefaniak, VP-Global Logistics F. Quinn Stepan, Chmn. 

Acknowledgments This chapter was supported by grants from the U.S. Agency for International Develop-ment, the National Science Foundation, and the A.W. Mellon Foundation to the Woods Hole Research Center. Further support was provided by the Conselho Nacional de Pesquisa (CNPq), to P. Moutinho. E. Cheng and V. Mendes Jr. assisted with data collection. K. Schwalbe and G. Carvalho assisted with data analysis and graphics. Dan Richter provided laboratory facilities. The Woods Hole Research Center and the Amazon Institute of Environmental Research (IPAM) provided institutional and logistical support. 

The utilisation of local biomass and residues (constmction and demolition wood, park and garden residues) can be decentralised in most cases, imposed by fuel availability and logistics. In this case the size of the conversion installations is generally limited to small or medium scale (15-100 MW thermal input). For these installations the cost of products distribution is a major parameter in the economics (Figure 2). 

C/min. These experiments show the considerable importance of moisture content regarding mass and energy flows the other characteristics are of secondary importance. The results lead to the development of a phenomenological modelling of mass and energy flows of the total volatile matter produced through wood carbonization in retort kilns, based on the logistic symmetric function. 

A very highly significant effect of the moisture content of wood on the symmetric logistic function is observed as would be expected (table 2 and figure 2). 

As expected, the factor M (maximal mass of matter volatilized) is significantly influenced by the moisture content of wood. The difference between anhydrous and wet wood samples is naturally explained by the quantity of water which has to be evaporated, contributing to an increase of the value of M for the symmetric logistic functions for wet wood samples (H37),... 

Table 3 Mean values and standard error (italic) of the parameters of the symmetric logistic function adjusted to the total volatile matter production from anhydrous wood samples (HO) carbonization.

The mean values of the parameters of the symmetric logistic function are given in table 6. We have identified significant effects of the shape and the species on factor a and b of the total energy production, as well as a significant interaction between shape and species. Blocks 16 of poplar are characterized by a total energy flow delayed and slowed down compared to other wood samples. 

The major fact resulting from the analysis of mass flow from wood carbonization is the general and considerable effect of moisture content on the process. The effect on the factor M of the symmetric logistic function (maximal mass of volatile matter produced at an infinite time) is expected the water present in wood is evaporated and constitutes a part of the volatile matter. It is thus natural to observe a factor M higher for wet wood samples (H37) than for anhydrous samples (HO). 

The effect of moisture content on the two other factors of the symmetric logistic function (a - time corresponding to 50 % production, b - indicator of the speed of reaction) is also noteworthy. Confirming the results of orientation experiments (moisture content dimension) [52] these results demonstrate the delaying and slowing down effects of the water presents in wood on the carbonization process. 

The adjustment of the symmetric function to the energy flows from wood carbonization is an original and dynamic (and no more static) approach. The analysis of the symmetric logistic function demonstrates again the dramatic effect of water. As for mass flows, energy flows are delayed and slowed down for wet wood samples (H37). Water intervenes through the large quantities of heat it requires to he evaporated and eliminated from the solid matrix. 

The second problem associated with the determination of wood density is strictly one of logistics that is, exactly how should the necessary measurements be made, particularly that of volume If all wood samples of interest could be easily dressed to perfect geometrical shapes, volume measurement would not be a problem. However, this is not the case, and density information is often desired for large specimens, irregularly shaped specimens, or small samples of earlywood or latewood of a single growth increment. 

Wood DF. International Logistics. Chapman Hall Materials Management/Logistics. 1994. 

Murphy Jr., P. R. and D. Wood. 2011. Contemporary Logistics, 10th edn. Upper Saddle River, NJ Prentice Hall. 

The product line is broad, with more that 100 specific items carrying manufacturer stock numbers. Each item can also be finished with multiple ophons. Many products are also upholstered with custom fabrics. TLC can choose to have e wood finish done af fhe factory or by a local (Los Angeles) finisher — a form of "postponement" described in Chapters 26 and 27. TLC preferred the factory finish for consisfency and lack of hassles in arranging the logistics of moving fhe ifem to the finisher and back — and tracking each item in the process. 

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