Pyrolysis continued drying

A report on the continuous flash pyrolysis of biomass at atmospheric pressure to produce Hquids iadicates that pyrolysis temperatures must be optimized to maximize Hquid yields (36). It has been found that a sharp maximum ia the Hquid yields vs temperature curves exist and that the yields drop off sharply on both sides of this maximum. Pure ceUulose has been found to have an optimum temperature for Hquids at 500°C, while the wheat straw and wood species tested have optimum temperatures at 600°C and 500°C, respectively. Organic Hquid yields were of the order of 65 wt % of the dry biomass fed, but contained relatively large quantities of organic acids. 

Titanium disulfide can also be made by pyrolysis of titanium trisulfide at 550°C. A continuous process based on the reaction between titanium tetrachloride vapor and dry, oxygen-free hydrogen sulfide has been developed at pilot scale (173). The preheated reactants ate fed iato a tubular reactor at approximately 500°C. The product particles comprise orthogonally intersecting hexagonal plates or plate segments and have a relatively high surface area (>4 /g), quite different from the flat platelets produced from the reaction between titanium metal and sulfur vapor. The powder, reported to be stable to... 

Beside continuous horizontal kilns, numerous other methods for dry pyrolysis of urea have been described, eg, use of stirred batch or continuous reactors, ribbon mixers, ball mills, etc (109), heated metal surfaces such as moving belts, screws, rotating dmms, etc (110), molten tin or its alloys (111), dielectric heating (112), and fluidized beds (with performed urea cyanurate) (113). AH of these modifications yield impure CA. 

Structure of cellulose polymer and determination of molecular weight Pyrolysis of nitrocellulose Thcrmochemical properties of nitrocellulose Mixed esters nitrates and sulphates Stabilization of nitrocellulose Knccht compound Manufacture of nitrocellulose Semi-continuous methodof Bofors-Nobel-Chematur Drying of nitrocellulose Safety in the manufacture of nitrocellulose Starch nitrates (nitrosiarch)... 

The authors had already conducted the laboratory scale study and the preliminary pilot plant study, and proposed that "drying-pyrolysis process" (pyrolysis followed by indirect steam drying of dewatered sludge cake) (Fig,-i) could be one of the most economical and feasible alternatives for conventional incineration process. The authors have further conducted the feasibility study on a continuous system of "drying-pyrolysis process to evaluate the performance of the process in pilot scale, and to demonstrate its effectiveness as a thermal processing of sewage sludge. This paper presents the results of this pilot plant study. 

Pyrolysis samples that are not soluble must be applied to the wires in some other fashion. Finely ground samples may be deposited onto the wire from a suspension, which is then dried to leave a coating of particles on the wire. Another approach is to apply the sample as a melt, which then solidifies onto the wire. To attach materials that will not melt or form a suspension, some analysts flatten the wire or create a trough in it. Some samples are held in place by bending or crimping the wire around the material, although this introduces concerns about the thermal continuity of a... 

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