Wood chips, oven

InterTechnology Corp. (7) analyzed the energy plantation concept, in which fast growing plant species are cultivated for biomass yield. For a plantation of hybrid poplar, total capital and operating costs in an unspecified U.S. location - from clearing the land to delivering wood chips - require a total revenue per oven dry tonne of 15.25 (in early 1975 dollars)(Table III). This assumes a 15% after-tax return on equity. The estimate is based on a yield of 20.2 oven dry tonnes per hectare. For a yield of 9... 

Birch (Betula papyrifera) wood chips used in this work were obtained from Scierie John Lewis, a woodmill in the province of Quebec, Canada. The sample was composed of 53.5 % of sap wood and 46.5 % of inner and outer bark. The moisture content was 8.5 % as determined by placing a known quantity of sample in an oven at 102 3 C until a constant weight was reached. The elemental composition of the sample was 51.3 % C, 6.2 % H, 0,7 % N and 41.8 % O (by difference). Its ash content was 2,0 %,... 

Soft wood chips weighing 17.2 kg are placed in an iron vessel and mixed with 150.1 kg water and 22.43 kg sodium hydroxide. A steel lid seals the vessel, which is then placed in an oven at 250°C for 6 hours. Much of the wood fiber decomposes under these conditions the vessel and lid do not react. 

Duplicate 12 mm thick three layers particleboard 600 mm x 300 mm in dimensions were prepared in the laboratory using 7 Z UF resin solids total on oven dry pine wood chips. The glue mix used was as follows ... 

Sample No. Virgin Oil Oven-aged pure oil (0 % wood chips) Oven-aged contaminated oil (2 wt % wood chips) ... 

Temperature-programmed thermogravimetry in inert gas gives a quick survey of the evaporation behavior, as shown in Fig. 4-144 for some polysiloxanes. For comparison, the TGA curves of a polyalphaolefm (sample 1) and of a perfluoroalkylether (sample 29) are also plotted. Those substances evaporate at considerably lower temperatures than the polysiloxanes despite their substantially higher viscosities. Similar behavior was observed in the isothermal gravimetry. For comparison the oven-aged samples (120 days at 220 "C both with and without wood chips) were also tested by thermogravimetry. The index numbers from those experiments are listed in Table 4-185. 

Curve 3 After Oven Aging with Addition of 2 wt% Wood chips 120 Days 220 °C... 

Table 4-187 Thermogravimetry of oven-aged silicone oils (aged with 2 wt % wood chips) in air.

Fig. 4-151 Oven Aging at 220 °C of Polylmethylphenylsiloxanes No. 13 16 % Phenyl Groups No. 24 30 % Phenyl Groups Viscosity versus Residence Time Parameter Concentration of Wood chips...

Sample Virgin oils Oven-aged without wood chips Oven-agec... 

Fig. 4-157 Correlation of the Oxidation Reaction Constant k (DSC, LTO) to the Viscosity Coefficient a(2) of the Polysiloxanes No. 11,19,20,24,26 (Samples Oven Aged with Addition of 2 wt% Wood chips)...

The starting material was spruce-chips with a mannan content of 12.9% (2). The heat-fractionation of milled spruce-chips was performed in a closed vessel in a microwave oven (MLS 1200 Microwave workstation. Milestone) with 9.1 g dry weight of wood chips in 100 ml of water solution (1, 2). Prior to the heat-fractionation, the milled spruce chips were impregnated (soaked) in either water or water solutions of sodium hydroxide (0.025-2%), potassium hydroxide (0.05%) or sulfuric acid (0.05%) (2). The heat-fractionation was performed at different temperatures and times, ranging from 170° to 220° C and 2 to 20 minutes, respectively. The solids were discarded by filtration and the filtrates were analyzed further. 

In Canada, InterGroup Consulting Economists (O estimated wood procurement costs in 62 forest zones across the country and generated cost data for the 20 zones having sufficient surplus roundwood to sustain a minimum 18,000 tonne per year methanol plant operation, based on a biomass recovery of 30%. The procurement costs shown in Table II represent the delivered chip cost, as in the Battelle study, but include capital and operating costs on an undiscounted cost basis. Unlike the Battelle study, the estimate is based on oven dry wood. The final results are very similar. 

Wood.—Sohd wood fuel prepared for the purpose, is occasionally used under boilers in the Northwest. Split fir at 3 per cord, delivered, is about equivalent economically to the local low-grade coals at 2.20 per ton. Refuse wood fuels (slab, edgings, chips and sawdust) are more frequently employed. Suitable methods of feeding must be provided fine particles may be blown long distances. If the moisture content is large, a special furnace on the Dutch oven principle may be found necessary. Woods contain very little ash. 

Mass of water in the chips Mass of water + oven - dry wood... 

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