Manual heating, thermal cutting and gouging

Thermal combustion and oxygen chemisorption of wood exposed to low temperature long term heating 1

... during initial period of wood drying Model Model o Temperature ( C) 58 54 50 46 1. 00 1. 01 1.03 1. 04 1. 05 1. 06 1. 08 1. 09 1. 10 1. 12 Distance from centre (mm) (Graph taken from Zhang and Datta (2004), ... self -heating of wood chars 1. 3 Scope of work Taking into consideration of the above objectives, the focus of this thesis is on thermal combustion and oxygen chemisorption of preheated wood at low ... important to elucidate the kinetics of oxygen chemisorption in order to evaluate the autoignition potential of low temperature wood chars that have been pre -exposed to prolonged heating Thermal...

Thermal combustion and oxygen chemisorption of wood exposed to low temperature long term heating 2

... primary wood degradation mechanisms of such description is based on Shafizadeh and Chin (1977) work which expresses the decomposition as k1 WOOD → TAR (2. 22) k2 WOOD → GAS (2. 23) k3 WOOD → CHAR (2. 24) ... exp(− K / Ts ) pv , sat where K1 and (2. 8) K are constants which depend on the temperature range, and K1 4.143 ×1010 Pa and K = 4 822 K in the temperature range of 20 °C to 1000°C = The assumption that ... 1, 2, (2. 21) where Svj is the volatile part of component of j of wood; G ↑ denotes volatile gas produced; ∆H , E , A represent heat of pyrolysis, activation energy and pre-exponential factor...

Thermal combustion and oxygen chemisorption of wood exposed to low temperature long term heating 3

... and erratic velocity profile   S-curve temperature profile  COUPLED VELOCITY AND TEMPERATURE DEVELOPMENT IN SELF -HEATING Figure 3. 1: Salient features of porous models for low- temperature long- term ... a factor of has been applied onto the porosity of green wood to derive the porosity of preburn wood, since pre-burn wood in this study has a 50% degree of pre-burn Therefore, the pre-burn wood ... fraction of the medium According to a study by Usta (20 03) , the green wood has a porosity of 0.4; the porosity of preburn wood is determined by the degree of preburn When modelling preborn wood in...

Thermal combustion and oxygen chemisorption of wood exposed to low temperature long term heating 4

... λ s λ (4. 47) Substituting Equations (4. 46) and (4. 47) into Equation (4. 45) yields C1 as C1 = Substituting Equation (4. 48) and H =  ′′ qe (4. 48)  s  + h s k  λ  h into Equation (4. 46), then ... 10 644 6 24 640 640 636 6 24 708 652 628 6 64 External heat flux &e q′′ (kW m-2) 50a 40 a 30a 25a 20a 15b 11c 10c 9c 8c Time to ignition tig (hr:min:s) 0:0:26 0:0: 54 0:1 :48 0:5: 24 0:12 :44 0:53 :42 ... content ( M ) of green wood was found to be 13.86%, the three constants in Equation (4. 13) were taken to be A = 0.0018 64 , B = 0.1 941 and C = 0.0 040 64 according to Wood Handbook 107 Chapter 4: Spontaneous...

Thermal combustion and oxygen chemisorption of wood exposed to low temperature long term heating 5

... a ratio of 1:100 (see Figures 5. 5 and 5. 6.) Discs 12.7 mm diameter and mm thick (see Figures 5. 7 and 5. 8) were pressed in a vacuum KBr press (Perkin-Elmer) at 100,000 psi Figure 5. 5 Wood samples ... grinding the wood discs sliced from the wood blocks and sieved to the desired particle size of 200 to 300 μm The wood powders were stored at 50 %RH at 23°C in a desiccator These wood chars were ... chemisorption temperature to equilibrate and to establish the weight of the sample prior to chemisorption Chemisorption was initiated by valving air with a flow rate of 60 ml/min into the furnace...

Thermal combustion and oxygen chemisorption of wood exposed to low temperature long term heating 6

... 6. 2 Heat and mass transfer in porous slab Self -heating and spontaneous combustion of wood was studied using wood cube of critical size exposed to low- temperature, long- term heating in an isothermal ... 25 20 15 11 10 26 54 108 324 764 3222 7990 7554 463 .01 465 .70 431. 06 4 36. 06 402. 16 367 .60 315. 26 298.38 266 .5 373.4 374.9 375.9 373.9 460 .5 345.4 342.4 287.4 250.1 370.7 (-957 .68 1) (903.9584) ... ′ Incident heat flux q e′ (kW/m ) Time to flaming ignition tig (hr:min:s) 64 4 50 62 4 40 64 0 30 64 0 25 63 6 20 62 4 15 708 11 65 2 10* 62 8 66 4 * Only one out of three samples tested at 10kW/m2 ignited...

Thermal combustion and oxygen chemisorption of wood exposed to low temperature long term heating 7

... the body of knowledge on thermal combustion and oxygen chemisorption of wood in the following areas: evaporation, liquid water transport, role of moisture in thermal combustion and oxygen chemisorption ... addition to thermophysical approach to examine self -heating and spontaneous combustion of low- temperature, long- term preheated wood, targeted to minimize unwanted fires arising from the wood structures ... structures and construction in historical and modern buildings The next section presents the conclusions and contribution of knowledge to the thermal combustion and propensity of preheated wood chars exposed...

Tài liệu Manual on the Production and Use of Live Food for Aquaculture - Phần 1 pptx

... organisms as feed for the developing larvae The aim of the present manual was therefore to review and summarise the latest developments concerning the production and use of the major live food organisms ... also the production and use of live food organisms as feed for the developing larvae The present manual describes the major production techniques currently employed for the cultivation of the ... Bijnens, Magda Vanhooren and March Verschraeghen for their assistance with the layout of the manual Lavens, P; Sorgeloos, P (eds.) Manual on the production and use of live food for aquaculture FAO Fisheries...

Tài liệu Manual on the Production and Use of Live Food for Aquaculture - Phần 2 doc

... - - Urea 7.5 - 1 2- 1 5 - 1 0-1 5 Calcium superphosphate 25 15 50 - - - Clewat 32 - - - - - N:P 16 /20 fertilizer - - - 1 0-1 5 - - N:P:K 1 6 -2 0 -2 0 - - - - 1 2- 1 5 - N:P:K 1 4-1 4-1 4 - - - - - 30 2. 3.1 .2 ... 7. 92 Algal-1 4.11 32. 22 8.83 8.65 Walne 4.04 13.37 13 .22 22 .28 ES 4 .24 14.88 15.73 23 .94 F /2 4.97 13 .26 17.91 23 .67 Algal-1 8.45 18. 82 11.08 18.18 Walne 10.11 5.17 4 .28 25 .95 ES 12. 09 7 .23 5 .21 ... Malony 0.1 0.4 1 0-1 5 5-1 50 10 2- 1 05 4.103 0 .2 1 0 -2 0 5-7 5 10 4-1 07 Speirs Levy Improved Neaubouer 2. 104 0.1 2 0-4 0 (phase) 2- 3 0 10 4-1 07 Petroff Houser 2. 105 0. 02 4 0-1 00 0. 5-5 10 4-1 08 Cellular volume is...

Tài liệu Manual on the Production and Use of Live Food for Aquaculture - Phần 3 ppt

... - 150 0. 53 53 - 80 150 - 200 0.47 70 - 93 200 - 250 0.40 80 - 100 250 - 30 0 0 .37 92 - 110 30 0 - 35 0 0 .33 100 - 117 35 0 - 400 0 .30 105 - 120 400 - 450 0.27 107 - 120 450 - 500 0. 23 105 - 117 > ... Upscaling of stock cultures to starter cultures 3. 5 .3. 3 Mass production on algae 3. 5 .3. 4 Mass production on algae and yeast 3. 5 .3. 5 Mass culture on yeast 3. 5 .3. 6 Mass culture on formulated diets 3. 5 .3. 7 ... generations of offspring before they eventually die The reproduction activity of Brachionus depends on the temperature of the environment as illustrated in Table 3. 1 The life cycle of Brachionus...

Tài liệu Manual on the Production and Use of Live Food for Aquaculture - Phần 4 pptx

... A par Basra - - Dayala - - Mahmoodia - - Urmia Lake B A urm Schor-Gol - - Shurabil - - Athlit - - Eilat North P A par Eilat South - - Chang Dao - - Tamano - - Yamaguchi P A par - - India Madras ... specific and remain relatively constant, (i.e they have become genotypical as a result of long-term adaptations of the strain to the local conditions; see chapter 4. 1.2 .4) 4. 1.2 .4 Strain-specific ... Vedaranyam - - Veppalodai - - Pattanamaruthur - - Spic Nagar - - Thirespuram - - Karsewar Island - - Saltwater springs P A par Harbour - - India Kanyakumari Thamaraikulam P A par Iraq Abu-Graib,...

Tài liệu Manual on the Production and Use of Live Food for Aquaculture - Phần 5 docx

... weeks, the use of decapsulated cysts constitutes a saving of over one third in the amount of Artemia cysts used, compared to the use of live nauplii Table 4.2.4 The proximate composition (in % of ... valorization of an otherwise inferior product The cysts have the appearance and the practical advantages of a dry feed and, in contrast to Artemia nauplii (47 0 -5 50 µm), their small particle size (20 0-2 50 ... nauplii it is converted into the more stable trans-canthaxanthin 4.2 .5 Hatching 4.2 .5. 1 Hatching conditions and equipment 4.2 .5. 2 Hatching quality and evaluation 4.2 .5. 1 Hatching conditions and equipment...

Tài liệu Manual on the Production and Use of Live Food for Aquaculture - Phần 6 docx

... 2 0-2 3 3. 0-4 .3 3-1 1 5-7 2 4-2 7 1 4-1 7 7-1 0 1 7-2 0 1 0-1 5 2 8-2 9 2-5 3 0-3 4 20 1 0-1 5 1 0-1 5 3 5-3 7 20 2 0-3 0 3 8-4 1 0.05 20 3 0-4 0 Start of weaning 2 0-1 5 1 5-1 0 4 5-5 5 1 5-2 5 1 0-0 0.08 4 0-5 0 4 5-5 5 4 5-5 5 For example, ... P monodon PL-15 and the osmotic resistance of PL-10 This has recently been confirmed with the production characteristics of P monodon PL-10 and PL-20 being significantly improved when HUFA-fortified ... levels of thiamin ( 7-1 3 µg.g-1), niacin (6 8-1 08 µg.g-1), riboflavin (1 5-2 3 µg.g-1), pantothenic acid (5 6- 7 2 µg.g-1) and retinol (1 0-4 8 µg.g-1) A stable form of vitamin C (ascorbic acid 2-sulphate)...

Tài liệu Manual on the Production and Use of Live Food for Aquaculture - Phần 7 pptx

... and attractive for the predators Table 4.4.3 Artificial seawater formulations used for tank production of Artemia (ing.l-1) For the Dietrich and Kalle formulation, solutions A and B are prepared ... influence the feeding behavior of Artemia by affecting the filtration rate, ingestion rate and/ or assimilation: including the quality and quantity of the food offered, the developmental stage of the ... the food tank should be large enough to hold the highest daily food ration at a maximum concentration of 200 g food. l-1 Even at these concentrations, the food suspension is so thick that the...

Tài liệu Manual on the Production and Use of Live Food for Aquaculture - Phần 8 pptx

... copepods and is also very toxic for shrimp The degradation of rotenone, chlorine and CaO to non-toxic forms is fairly rapid (24 - 48 h) If on the other hand tea-seed cake or dipterex are used, ponds ... accumulates on the pond bottom, they should only be used for a limited period of time Recommended levels of organic manure are 0.5 to 1.25 ton.ha-1 at the start of the production season with dressings of ... analysis of the algae samples is recommended Algae composition does not only influence growth and reproduction of the Artemia, but also has an effect on the nutritional value of the biomass and the...

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