Showing papers on "Sawdust published in 1984"

Laccase production and wood degradation by Trametes hirsuta

Abstract: The laccase production byT. hirsuta was better in lignin as compared to malt extract media. Tannic acid gave the best laccase yield out of different lignins, phenolic compounds and sugars tested as substrates. The sugars proved to be good substrates for growth only. The role ofT. hirsuta in semisolid fermentation of sawdust was studied with reference to its capacity to degrade lignin in its native form. During two months of decay an overall weight loss of 22.2% along with a lignin loss of 13.6% was recorded.

New aspects in cationization of lignocellulose materials. I. Preparation of lignocellulose materials containing quarternary ammonium groups

Abstract: TMAHP derivatives were prepared by the reaction of beech sawdust with CHMAC in alkaline medium. The examination of the reaction conditions showed that the most suitable molar ratio was NaOH/CHMAC = 1.8 (1 ml 17.5% NaOH/1 mL 50% CHMAC). At this ratio the maximum degree of substitution expressed by the exchange capacity of 0.35 mmol/g of modified sawdust was obtained by using 1.5–2mL of 50% aqueous solution of CHMAC/g sawdust. The optimal reaction time at 60°C was 2 h. This condition gave yields of modified sawdust above 90% and soluble derivatives mainly consisting of hemicelluloses up to 12%.

Laboratory Evaluation of Malathion-Treated Sawdust for Control of Stored-Product Insects in Empty Granaries and Food Warehouses

Abstract: Spruce sawdust impregnated with malathion was assayed by chemical and biological methods to determine whether it was an effective and economical formulation to control stored-product insects in empty storage structures. The size of sawdust particles (fine: 0.250–0.425 mm; medium: 0.425–0.840 mm; coarse: 0.840–2.0 mm) did not affect the residual activity of malathion on a given surface during 8 weeks at 25°C and 50% RH. However, malathion on the sawdust decomposed more rapidly on concrete surfaces than on wood surfaces. Sawdust containing 0.4, 0.8, and 2.0%(AI) malathion was stored on concrete, wood, or galvanized steel for 16 weeks at 25 and 50% RH. The sawdust and surface beneath the sawdust were bioassayed with Tribolium castaneum (Herbst) adults for exposure periods of 1, 3, or 24 h. Sawdust initially treated with 0.4% malathion (4,148 ppm) was relatively effective for up to 4 weeks after a 3-h exposure of insects only on steel; wood and steel surfaces under the treated sawdust were very toxic to insects for 8 to 12 weeks, respectively. Sawdust initially treated with 0.8% malathion (7,430 ppm) was ineffective on concrete surfaces, and gave 100% mortality of T. castaneum exposed for 24 h for 12 weeks on steel and 16 weeks on wood. Sawdust initially treated with 2% malathion (20,442 ppm), gave nearly 100%mortality for 4 weeks (3-h exposure) on concrete and 16 weeks (3-h exposure) on wood and steel. For up to 12 weeks, sufficient malathion had been transferred to the concrete surface to kill 100%of insects in 24 h; 100% mortality occurred on wood and steel surfaces for up to 16 weeks.

Fuel mixt. useful as coal substitute - comprising coal dust, paper pulp, filler and coating of tar, etc., has calorie cost lower than coal

Abstract: Fuel comprises: (i) 30-60% coal dust; (ii) 5-20% paper pulp; (iii) one or more of the fillers (iiia) 20-60% (relative to dry fuel) of clay, sand or earth, (iiib) 0-15 wt.% sawdust, (iiic) 5-20 wt.% water, and (iiid) 0-60% further organic materials and combustible materials from industrial and domestic refuse; and (iv) tar, pitch or asphalt, which protects the prod. facilitates its handling and gives it a pleasing appearance. The coal dust may be a byprod. of coal mining, or may be obtd. by grinding. The paper pulp may be replaced by similar pulp from e.g. straw or wood: this component acts as binder and provides some calories on combustion. Component (iv) may be applied as emulsion, soln. or melt. USE/ADVANTAGE - Useful as a coal substitute. The properties are similar to those of coal, but the cost per calorie is 25-35% less, and heat liberation lasts longer. Under-utilised and waste materials are used.

Alternative methods for using organic materials composting vs. adding directly to soil

Abstract: Composting organic wastes before applying them to the soil helps to produce a relatively homogeneous, odor‐free, easy‐to‐handle material. Also, it may destroy or deactivate weed seeds and many plant and animal pathogens. Decomposition of residues before they are added to the soil will presumably have different effects than allowing them to decompose in the soil, but effects on soil fertility and microbiology have been little studied. This paper describes research on the influence of composting on soil nitrogen availability, cation exchange capacity, organic matter content, and structure. Sewage sludge was added to the soil either directly, or first mixed with sawdust, or first composted with sawdust, in each case at rates equivalent to 150, 300, and 900 ppm N. The amended soils and a no treatment check soil were placed in pots that were either planted to ryegrass or allowed to incubate. Ryegrass yields were greatest for the direct application of sludge, while either composting or mixing with sawd...

Natural woodlog of prepared waste wood

Abstract: The invention relates to a completely novel recycled wood product which can be used as firewood or as an energy medium in industry. It is independent of shape and can be compressed to give any shape. The composition of the invention is variable in a range of: Residual wood Additives Auxiliaries Wood chips Waxes, Paraffins Essential oils, Sawdust Adhesives Flame-colouring Shavings agents Fragrancies % by weight in each case 50 - 100 0 - 50 10 Printed films, thin-walled materials or natural structures are used for covering. Treatment of the outer surfaces can also be effected by printing, immersion or spraying methods.

Manufacture of molded activated carbon using wood as principal starting material

Abstract: PURPOSE:To manufacture molded activated carbon having superior mechanical strength and adsorbing performance by adding a small amount of tar and pitch to wood flour, pelletizing them, and carbonizing and activating the pellets. CONSTITUTION:Scrap wood, sawdust, etc. are crushed into wood flour, and the flour is sieved with a sieve of 4-6mm. size and dried to <=10% water content. The dried flour is mixed with 5-20wt% coal tar and pitch. The mixture is extruded from the hole of dies and cut to form cylindrical pellets, and the pellets are cooled by forced ventilation. The cooled pellets are fed to a carbonization furnace, where they are carbonized by heating at 500-600 deg.C in a nonoxidizing atmosphere for about 30min. Carbohydrate in the pellets is thermally decomposed, and water and volatile matter are evaporated. The pellets are provided with a porous structure by the carbonization. The pellets are then activated by heating to about 850 deg.C in the absence of oxygen in a rotary kiln to obtain molded activated carbon having superior mechanical strength.

Cellulolytic activity of white, brown and gray wood rot fungi.

Abstract: Culture fluids obtained from submerged cultures of white, brown and gray wood rot fungi were assayed for the presence of cellulolytic activity complexes against the model substrated carboxymethylcellulose-Na and Standard Whatman cellulose and natural substrates, i.e. celluloses isolated from pine bark and sawdust. The cellulolytic activity of the examined fungal species was highly differentiated. The use of model and natural substrates allowed determination of the high substrate specificity of the cellulase complexes produced by the fungi. Not all the fungi were found to produce EC 3.2.1.4. endo-1, 4-beta-glucanase under the culture conditions employed. All the fungi were, however, able to produce a complex of EC 3.2.1.4. exo-1, 4-beta-glucanases. All the examined fungi were also able to degrade, although to a varied extent, such higher forms of cellulose as Standard Whatman cellulose or natural celluloses isolated from pine bark and sawdust. Determination of the cellulolytic activity of fungi against the above-mentioned specific natural substrates affords the possibility of their practical use.

Anti-deflagration device and its adaptation to central heating in a sawdust burning stove with direct fuel-loading and a central flue.

Abstract: The invention relates to a method which makes it possible to eliminate deflagrations produced by vertical sawdust burning stoves in the course of operation The anti-deflagration device consists of a combination of a central venturi cylinder which is frustoconical (3) at the top and flared at the bottom, provided with notches (6) and placed in the central flue (9) consisting of the sawdust and of an elbowed tube (4) which connects the edge of the nozzle hole of the hearth (2) to the edge of the smoke pipe (5) The method according to the invention makes it possible to eliminate the deflagrations of vertical sawdust-burning stoves, and a venturi variation makes it possible to adapt it to central heating It is intended to make possible the incineration of dry sawdust and green resinous sawdust, and the production of direct heat or of hot water