Showing papers on "Sawdust published in 1994"

Hydrodynamics of sawdust and mixtures of wood residues in conical spouted beds

Abstract: It has been proven that conical spouted beds allow for stable operation with sawdust and with wood residues, even with mixtures of these materials of wide particle size range and without being diluted with an inert solid. Peculiar hydrodynamic characteristics for sawdust have been observed; a great hysteresis in the pressure drop vs velocity curve, a pronounced peak of maximum pressure drop, and a difference between the velocity for which spout and fountain are formed and the velocity of the fully spouted bed. From the hydrodynamic study of sawdust, the ranges of the contactor geometric factors (cone angle, inlet diameter/base diameter ratio, inlet diameter/particle diameter ratio) for which operation is stable have been determined. Original correlations for calculation of minimum spouting velocity, of stable operation pressure drop, of maximum pressure drop, and of minimum voidage of complete spouting have been proposed.

Use of conifer volatiles to reduce injury caused by carrot psyllid,Trioza apicalis, Förster (Homoptera, Psylloidea)

Abstract: The feeding and oviposition of the carrot psyllid,Trioza apicalis, were reduced by the application of fresh spruce and pine sawdust along the seedling rows in carrot fields. Turpentine and separate monoterpene hydrocarbons, mixed into old sawdust and/or placed in polyethylene tubes, were also effective. At a dose of 0.5 liter/m, fresh sawdust reduced the damage to 18% of the plants, compared to 100% damage in untreated plants. The sawdust materials were spread on the soil surface at four- or seven-day intervals during the oviposition period. The tubes were placed along the carrot rows before the oviposition started. Turpentine and separate monoterpene hydrocarbons afforded a protective effect of the same order of magnitude as that obtained from fresh sawdust. The volatile profiles of the spruce and pine sawdust as well as of the turpentine used were determined.

Effect of environmental parameters on the degradability of polymer films in laboratory-scale composting reactors

Abstract: Previous research in our laboratory reported a convenient laboratory-scale composting test method to study the weight loss of polymer films in aerobic thermophilic (53°C) reactors maintained at a 60% moisture content. The laboratory-scale compost reactors contained the following synthetic compost mixture (percentage on dry-weight basis): tree leaves (45.0), shredded paper (16.5), food (6.7), meat (5.8), cow manure (17.5), sawdust (1.9), aluminum and steel shavings (2.4), glass beads (1.3), urea (1.9), and a compost seed (1.0) which is designated Mix-1 in this work. To simplify the laboratory-scale compost weight loss test method and better understand how compost mixture compositions and environmental parameters affect the rate of plastic degradation, a systematic variation of the synthetic mixture composition as well as the moisture content was carried out. Cellulose acetate (CA) with a degree of substitution (DS) value of 1.7 and cellophane films were chosen as test polymer substrates for this work. The extent of CA DS-1.7 and cellophane weight loss as a function of the exposure time remained unchanged when the metal and glass components of the mixture were excluded in Mix-2. Further study showed that large variations in the mixture composition such as the replacement of tree leaves, food, meat, and sawdust with steam-exploded wood and alfalfa (forming Mix-C) could be made with little or no change in the time dependence of CA DS-1.7 film weight loss. In contrast, substituting tree leaves, food, meat, cow manure, and sawdust with steam-exploded wood in combination with either Rabbit Choice (Mix-D) or starch and urea (Mix-E) resulted in a significant time increase (from 7 to 12 days) for the complete disappearance of CA DS-1.7 films. Interestingly, in this work no direct correlation was observed between the C/N ratio (which ranged from 13.9 to 61.4) and the CA DS-1.7 film weight loss. Decreasing moisture contents of the compost Mix-2 from 60 and 50 and 40% resulted in dramatic changes in polymer degradation such that CA DS-1.7 showed an increase in the time period for a complete disappearance of polymer films from 6 to 16 and 30 days, respectively.

Growth of chrysanthemum with ground automobile tires used as a container soil amendment

Abstract: A study was conducted to determine the potential for using ground automobile tires as a container medium amendment. Rooted cuttings of chrysanthemum (Dendranthema × grandiflorum (Ramat.) Kitamura) were planted in 1.56-liter pots containing 1 sand :2 sawdust (v/v) or media in which coarsely or finely ground particles of rubber substituted for 33%, 67%, or 100% of the sawdust. Amendment with the coarse material decreased total porosity and container capacity and increased air-filled porosity and bulk density relative to the sawdust control. Amending the medium with the fine material did not appreciably alter total porosity, container capacity, or bulk density, but did increase air- filled porosity. Plant height, fresh weight, dry weight, and number of open flowers were reduced significantly in rubber-amended media compared to sawdust controls. Rubber amendment reduced shoot tissue concentrations of N, P, K, Ca, Mg, and Cu, but increased Zn as much as 74-fold over control values. There was no accumulation of other heavy metals (Cd, Cr, Ni, Pb) or Na in the tissue due to rubber amendment. This study demonstrates that ground tires might be used as a component of container media in the production of greenhouse chrysanthemums. However, growth reductions and the poten- tial for Zn toxicity may limit the usefulness of ground tires as a substitute for conventional organic amendments. Horticultural container media may be for- mulated from a variety of materials, with the goal to optimize physical and nutritional char-

Bioeemediation of petroleum‐contaminated clayey soil with pretreatment

Abstract: Petroleum‐contaminated clayey soil destined for bioremediation on site requires pretreatment to change its density and its transmissibility. A feasibility study was performed to develop the conditions for the oil and grease reduction in the contaminated soil and to evaluate the influence of sawdust, nutrients and oxygen addition on the biodegradation process. The study demonstrated depletion of oil and grease concentration below 1000 mg kg‐1 (class B level ‐ Ministry of Environment Quebec) as well as the specific retardant influence of the sawdust additive.

The relationship between phenol oxidase activity, soluble protein and ergosterol with growth of Lentinus species in oak sawdust logs

Abstract: The growth of four strains of the shiitake mushroom Lentinus edodes in solid substrate fermentation in synthetic oak sawdust logs was studied over a 14-week period. Total extracellular phenol oxidase activity and soluble protein were monitored and biomass estimated as the ergosterol content of the fermented sawdust. It was observed that two of the strains had a similar pattern of phenol oxidase activity with two cycles with maxima at 2 and 8 weeks of mycelial growth prior to fruiting. With the other two strains there was a maximum at week 4. For each strain, phenol oxidase activity increased with the cold shock used to induce fruiting. Phenol oxidase activity was not found to be correlated with either soluble protein or total fungal biomass in the fermented sawdust, which were correlated for each strain. Quantification of biomass from submerged liquid culture on the basis of dry weight and ergosterol contents showed that the strains fell into the same two groups with respect to the ergosterol to biomass ratio, which was markedly lower than that for a strain of L. lepideus.

Process for treating waste materials with concentrated acid and the product produced thereby

Abstract: A process for treating wood, particularly wood wastes (such as sawdust and the like), and/or paper, particularly waste paper (such as newsprint), and/or other types of polysaccharides (matter composed essentially of cellulose and lignin), preferably available as 'wastes', with concentrated sulfuric acid (93 to 98.5 % H2SO4), or with concentrated phosphoric acid (75 to 85 % H3PO4), or various mixtures of these acids in their concentrated forms. The product of the process can be used for treating agricultural soils or as a landfill.

Effect of Amendment on Nitrogen Conservation in Wastewater Biosolids Composting

Abstract: ▪ A study was conducted on a full scale in-vessel agitated bed process to determine the influence of two common amendments on nitrogen management. Sawdust and mulch were tested for their ability as...

Effective utilization of excess sludge

Abstract: PURPOSE:To develop the effective utilization by which excess sludge of food factories and night soil or sewerage treatment plants can be recycled. CONSTITUTION:When quick lime (calcium oxide) is added to the excess sludge, the quick lime reacts highly exothermically with water in the sludge to form calcium hydroxide (slaked lime). As a result various microorganisms in the sludge is completely killed and the sludge is partly hydrolyzed by the high alkalinity and temperature. Thereafter by adding straws, sawdust, and further tuff loam and leaf mold to the sludge and by fermenting the mixture, a completely aged organic manure can be produced. At the time of applying the manure to vegetables, excellent growth promotion of the vegetables without any adverse effect on them resulting from any applied amount of the manure can be attained. On the other hand sulfuric acid is added to the excess sludge and the resulting sludge is neutralized with an aqueous suspension of slaked line and then sawdust is added to it. The mixture is sufficiently blended while stirring. At the time of using the mixture thus produced as a culture medium of Cortinellus shiitake (mushroom) and Pholiota nameko (mushroom), the growth of the hyphae of the mushrooms is remarkably promoted and also good yields and qualities of Cortinellus shiitake and Pholiota nameko can be attained.

Production of compound material of fiber and bacterial cellulose and composite material produced by the process

Abstract: PURPOSE: To provide a process for the production of paper having strength, color tone, printability with ink, feeling, etc., comparable to those of wood pulp paper by using a composition composed mainly of a vegetable-originated cellulose as a raw material. CONSTITUTION: This compound material composed of bacterial, cellulose and fibers of a cellulose-hemicellulose mixture is formed by inoculating a bacterial strain BPR200l (FERM BP-4545) belonging to the genus Acetobacter to a specific culture medium and culturing the bacterial strain at a prescribed temperature. The culture medium is composed mainly of at least one kind of vegetable- originated cellulose selected from squeezed cake of sugarcane, soybean, malt, coffee bean, fruit, etc., containing assimilable carbon source and/or nitrogen source, wheat bran, bean curd refuse, rice chaff, tea grounds, vegetable skin, fruit skin and sawdust, waste paper, etc., partially saccharified by cellulase treatment. The compound material is pulped by a paper-making double-disk refiner and paper is formed from the pulp after washing and bleaching. COPYRIGHT: (C)1995,JPO

Wood briquette for fuel

Abstract: PURPOSE:To obtain a briquette which has a calorific value equivalent to that of a high-grade charcoal made from an evegreen oak, a Japanese oak, etc., and retains a stable combustion characteristics for a long time by dispersing a carbon powder into a carbonized wood in a specified wt. ratio. CONSTITUTION:The briquette is prepd. by dispersing 2-25wt.% carbon powder, pref. a carbon black (e.g. Seast 3, a product of Tokai Carbon Co., Ltd.), into a carbonized wood pref. a carbonization product of sawdust or bark of a coniferous tree (e.g. a Japanese cryptomeria).

The effect of inoculum substrate and dew period on the pathogenicity of Sclerotinia sclerotiorum when applied as a mycoherbicide to Californian thistle (Cirsium arvense)

Abstract: Sclerotinia sclerotiorum was grown on solid substrates based on kibbled (cracked) wheat and pine sawdust with various additives to examine its potential as a mycoherbicide against Californian thistle (Cirsium awense). Mycelial growth was vigorous on wheat but very weak on sawdust. Growth was only marginally slower on a substrate of equal weights of wheat and sawdust than on wheat. The addition of vegetable oil to the substrates did not enhance the basic growth rates. The subsequent growth out of the fungus-infested particles into pure culture was faster from wheat than from sawdust particles in the wheat plus sawdust mixture substrate. The rate of lesion development on excised leaves of Californian thistle inoculated with these substrates reflected these differences. Neither vegetable oil nor oxalic acid as additives, increased the speed of infection or rate of lesion development. When plants of C. awense were inoculated in the glasshouse, the mycelium-infested sawdust plus wheat substrate gave slower disease development than the wheat substrate. Increasing the length of the dew period caused faster disease development, especially in the sawdust plus wheat substrate. These results suggest S. sclerotiorum will require a suitable energy source and free moisture when used as a mycelium-based mycoherbicide.

Management of the sawdust litter in the ‘pig-on-litter’ system of pig waste treatment

Abstract: In the ‘pig-on-litter’ system of livestock waste management, pig wastes were fermented in the sawdust litter with or without added microbial products in the substratum or to the feed. Weekly samples of the sawdust litter mere monitored for bedding temperature, moisture content, pH, urea, ammonia, nitrite, nitrate, phosphate, sulfphide, sulphate, chloride, fluoride, redox electrode potential reading, soluble and insoluble protein, CHN content, and sawdust particle sizes. It was found that for successful fermentation to take place, the moisture content must be kept low (about 50%). A bedding having good fermentation rates had higher pH due to trapped NH4+, and lower levels of urea, nitrite and nitrate, and soluble N, but had higher levels of insoluble protein and sulphate. Water-logging reduced aeration, promoted anaerobic fermentation, increased generation of sulphide, and accumulated substantial amounts of soluble nitrogen compounds which could not be accounted for as protein, urea, nitrite or nitrate. The changes in bedding composition suggested the release of volatile N products into the atmosphere while non-volatile P and Cl accumulated. F increased in proportion to the degree of moisture in the litter, suggesting that the source of water came mainly from drinking. A well managed system was found to effectively control the production of offensive odour.

Energy=producing process for accumulated raw material

Abstract: The energy-producing process involves burning the material, e.g. sawdust or wood chips, under partial vacuum in a combustion chamber (10), separating the residue (5), and taking the ash and dust particles along with the exhaust gas departing at about 1000 deg. C. The impure exhaust gas is purified at high temp. (25).This gas is then used in a Stirling engine (30) in which heat is given up in an energy conversion process. The heat from the exhaust gas can also be used for heating purposes (40), in the form of creating a flow in counter-pressure, or by a condensation process, or for use in drying plants.

Biocontrolled litter for small animals

Abstract: The invention consists of the production of a litter having components which make it possible to block the development of ammonia and of smells. It is composed of a mixture of pine or fir sawdust with an enzymatic bacterial complex compacted at low temperature (less than 60 DEG ) and immediately cooled.

Production of wood briquette for fuel

Abstract: PURPOSE:To produce a wood briquette for fuel which has high density and hardness and exhibits an excellent calorific power and a long-stable persistence of cocmbustion CONSTITUTION:A wood flour comprising sawdust or bark of a conifer is smoked at 200-400 degC, compression molded, and carbonized Pref the wood flour after the smoking is pulverized to a particle size of 300mum or lower

Silicon alloy high energy compound carbon catalyst and the process for prepn. of same

Abstract: In this invention, charcoal powder, petroleum coke, coal, and sawdust, are treated and mixed with adhesive of asphlt and tar, granulated mechanically and sintered at high temp.into granules. Due to the carbon content, water content, and grain size are optimally controlled, this invention posseses fine mechanical strength, uneasy breakage during production and application, the permeability of furnace burden increased, the reduction speed, degree, and reaction power are promoted, the quality of silicon product is increased, and the cost is reduced.

Biological deodorizing method using sawdust of needle-leave tree as carrier

Abstract: PURPOSE:To deodorize sulfur-based and nitrogen-based malodorous gases efficiently for a long duration by passing the malodorous gases through sawdust of needle-leave tree, especially, Japanese larch on which activated sludge or microbes are carried. CONSTITUTION:A malodorous gas is passed through sawdust 6 of a needle-leave tree, especially, Japanese larch on which active sludge or microbes are adsorbed to treat the gas. For the treating microbes to be used for the method, activated sludge collected from a sewage treatment site is preferably used and further in the case bacteria separated from the activated sludge is used, sulfur oxidizing bacteria, for example, thiobacillus thioparus of thiobacilli can be used suitably. For example, a malodorous gas produced out of a cattle stall is sucked by a blower 8, introduced through an inlet 3 of a deodorizing apparatus 1, introduced into the space filled with sawdust carrier of Japanese larch in a space 7 in the deodorizing apparatus 1, and discharged out of an outlet 5 as an odorless gas 4.

Packing method for living aquatic products

Abstract: The present invention relates to a packing method of living aquatic products with high survival rate. The said method is that to the inside wall of packing box dry sawdust is distributed, around aquatic product wet sawdust is spread, and dry and wet sawdust are separated with plastic film.

Apparatus for producing powdery charcoal

Abstract: PURPOSE:To provide an apparatus capable of continuously producing powdery white charcoal at a low cost using wood flour such as sawdust as a raw material. CONSTITUTION:Sawdust is heated at about 400-600 deg.C in a primary carbonization oven 1 composed of a primary combustion chamber 2 and a primary heating tube 3 to obtain low-temperature carbonized charcoal. The charcoal is heated at about 1000 deg.C in a secondary carbonization oven 8 composed of a secondary combustion chamber 9 and a secondary heating tube 10 to obtain powdery white charcoal.

Oxygen-absorbing quality-keeping agent

Abstract: Comprising iron powder, husk charcoal, sodium oxide, water, active carbon, lime and sawdust, the preserving agent has strong oxygen-absorbing capacity and thus excellent quality-keeping effect. It may be widely used in the storage of farm products, such as cereals, dry vegetable and tobacco as well as articles subject to mildew and worm-eating, such as medicine and cake.

Sawdust and hards plasticizing veneer sheet

Abstract: The said plasticized veneer sheet is produced via one-step compound plastication and by using waste sawdust, tow and plastics as main raw materials and adding low-toxicity urea-formaldehyde resin and curing agent. It has excellent physical and mechanical performance and may be widely used.

Sawdust composite board

Abstract: The composite sawdust board as a new decorative material comprises substrate board and face layer. The substrate board uses sawdust as filler, glass fibre cloth as skeleton material and magnesium oxychloride as binder and is modified by adding toughening agent and waterproofing agent. Decorative paper is then stuck onto the substrate board. It features resisting fire, moisture and ageing, smooth and bright surface and low cost.