Green Wood in the Bundle of Sticks

The strength and strains of the wood-cement composite primarily depend on the main technоlogical factors such as the used type of binder and wood filler, the method of wood filler preparation, the method of molding, the conditions of hardening. The aim of this work is an experimental study of the chemical additives influence on wood filler to localize the harmful effects of water-soluble wood substances on the processes of hydration and hardening of cement. Using the additives, it is possible to achieve satisfactory strength parameters even on green wood. The maximum strength was obtained when complex chemical additives were applied. The most effective additives involved calcium chloride, liquid glass, aluminum sulfate, lime and ethanolamines. The optimal consumption and ratio of the complex additives components costs also depend on the degree of preliminary wood exposure.

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THE EFFECT OF THE FILLING RATIO ON THE OPERATING CHARACTERISTICS OF AN INDIRECT DRUM DRYER

Acta Polytechnica ◽

10.14311/ap.2020.60.0049 ◽

2020 ◽

Vol 60 (1) ◽

pp. 49-55

Author(s):

Jan Havlík ◽

Tomáš Dlouhý ◽

Michel Sabatini

Keyword(s):

Specific Energy Consumption ◽

Filling Ratio ◽

Operating Characteristics ◽

Drying Time ◽

Green Wood ◽

Operational Characteristics ◽

Rotary Drum ◽

Drying Curves ◽

The One ◽

Drying Conditions

This article investigates the effect of the filling ratio of the indirect rotary dryers on their operating characteristics. For moist biomass drying before combustion, the use of indirect drum dryers heated by a low pressure steam has proven to be highly suitable. Regarding the design of new dryers, it is necessary to experimentally verify the operating characteristics for specific materials and drying conditions. For this purpose, a set of experiments on a steam heated rotary drum dryer were carried out with green wood chips containing 60 to 66 wt% of moisture. The following operational characteristics of the dryer were experimentally determined: drying curves describing the process, square and volumetric evaporation capacities and drying heat consumptions. Based on the experimental results, the effect of various drum filling by dried material on the mentioned operating characteristics was analysed. On the one hand, higher drum filling ratio increases the drying time, on the other hand, the evaporation capacity also increases, while the specific energy consumption does not significantly alter. The maximum value of the evaporation capacity was reached when the drum was filled to 20 wt%. When the filling ratio was increased to 25 wt%, the evaporation capacity experienced almost no change.

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Dual-energy X-ray absorptiometry with digital radiograph for evaluating moisture content of green wood

Wood Science and Technology ◽

10.1007/s00226-015-0726-8 ◽

2015 ◽

Vol 49 (4) ◽

pp. 713-723 ◽

Cited By ~ 4

Author(s):

Chul-Ki Kim ◽

Jung-Kwon Oh ◽

Jung-Pyo Hong ◽

Jun-Jae Lee

Keyword(s):

Moisture Content ◽

Dual Energy ◽

Green Wood ◽

X Ray ◽

Digital Radiograph

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OBITUARY. CHRISTOPHER GREEN WOOD SAMUELS, 1880-1916.

Minutes of the Proceedings of the Institution of Civil Engineers ◽

10.1680/imotp.1917.15823 ◽

1917 ◽

Vol 204 (1917) ◽

pp. 436

Author(s):

Keyword(s):

Green Wood

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Combined treatment of green pitch pine wood by heat and superheated steam and the effects on physical properties of the products

Holzforschung ◽

10.1515/hf-2013-0054 ◽

2014 ◽

Vol 68 (3) ◽

pp. 327-335 ◽

Cited By ~ 8

Author(s):

Yonggun Park ◽

Chang-Deuk Eom ◽

Yeonjung Han ◽

Jun-Ho Park ◽

Yoon-Seong Chang ◽

...

Keyword(s):

Heat Treatment ◽

Physical Properties ◽

Large Scale ◽

Superheated Steam ◽

Bending Strength ◽

Combined Treatment ◽

Decay Resistance ◽

Green Wood ◽

Heat Treated ◽

Pitch Pine

Abstract Pitch pine (P. rigida) wood was treated with superheated steam (SHS) and the subsequent effects due to drying and heat treatment (HT) were observed. The following treatment parameters were tested: 180°C air HT, 220°C air HT, 0.1 MPa–180°C SHS HT, 0.1 MPa–220°C SHS HT, 0.5 MPa–180°C SHS HT, and 0.5 MPa–220°C SHS HT. No drying checks were observed in the specimens (500×150×50 mm3) treated at 0.5 MPa–220°C SHS and with these treatment parameters, equilibrium moisture content (EMC) was the lowest. Low EMC has an effect on physical properties such as shrinkage, compressive strength parallel to the grain, bending strength, hardness, and decay resistance. Based on the results, it is expected that the green wood in a large scale is possible to be simultaneously dried and heat-treated without occurrence of checks by the SHS HT process.

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Modeling temperature effect on dynamic modulus of elasticity of red pine (Pinus resinosa) in frozen and non-frozen states

Holzforschung ◽

10.1515/hf-2014-0048 ◽

2015 ◽

Vol 69 (2) ◽

pp. 233-240 ◽

Cited By ~ 4

Author(s):

Shan Gao ◽

Xiping Wang ◽

Lihai Wang

Keyword(s):

Temperature Effect ◽

Modulus Of Elasticity ◽

Freezing Point ◽

Red Pine ◽

Analytical Models ◽

Clear Wood ◽

Green Wood ◽

Static Modulus ◽

Static Modulus Of Elasticity ◽

Increasing Temperature

Abstract The response of dynamic and static modulus of elasticity (MOEdyn and MOEsta) of red pine small clear wood (25.4×25.4×407 mm3) within the temperature range -40 to 40°C has been investigated. The moisture content (MC) of the specimens ranged from 0 to 118%. The MOEdyn was calculated based on measured ultrasonic velocity (V) and wood density. The MOEsta was measured by static bending tests in a climate chamber between -40 and 40°C. The results indicate that both MOEdyn and MOEsta were affected by temperature and the MC. Above freezing point, MOE decreased linearly at a slow rate with increasing temperature. Below freezing point, MOE increased at a rapid rate with decreasing temperature. The MC-level had a significant effect on the MOE-temperature relationships. Temperature effect was much more significant in green wood than in dry wood. Analytical models were developed to predict the change of MOEdyn relative to that at 20°C in the case of acoustic measurements under different temperature conditions.

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