Showing papers on "Sawdust published in 1981"

Smokeless fuel from carbonized sawdust.

Abstract: Carbonization of sawdust at 538 degrees gave charcoal useful as smokeless fuel; yield and calorific value (CV) of the fuel gas increased when the gases, tar, and pyroligneous liquor from carbonization were subjected to thermal cracking on firebrick, semicoke, or charcoal. When semicoke or charcoal was used, the tar and pyroligneous liquor were completely decomposed and the yield and CV of gaseous products obtained were higher than those obtained by cracking over firebrick.

Continuous high-solids acid hydrolysis of biomass in a 1 1/2-in. plug flow reactor

Abstract: A continuous pipe reactor fed with a twin-ram pump capable of handling biomass, sawdust, newspaper, straw, bagasse, corncob, and potato pieces, at 20-60% solids content was developed to produce glucose (I) and furfural (II) by hydrolysis with H2SO4. The I and II were obtained in 40-42% yield of theory from oak sawdust at 250 degrees, 4.5 min residence time, and 1.5% H2SO4, starchy materials gave I yields is less than or equal to 73%, and xylose in a 75-80% yield was obtained by continuous hydrolysis. Kinetic parameters for I production were also derived.

Solubilisation and hydrolysis of carbohydrates

Abstract: A process for the modification, solubilization and/or hydrolysis of a glycosidically linked carbohydrate having reducing groups using a mixture comprising water, an inorganic acid and a halide of lithium, magnesium or calcium. The process is particularly useful for converting cellulose (derived for example from waste-paper, wood or sawdust) or starch to glucose. When cellulose is the starting material the preferred halide is a lithium halide. When starch is the starting material a magnesium halide is preferred.

Apparatus and process for drying sawdust

Abstract: A sawdust drying apparatus and process wherein sawdust passes downwardly in a sinuous fashion to and through multiple, vertically spaced dryer plates at a temperature and velocity so as to progressively dry the sawdust and render it suitable as a highly combustible wood fiber fuel.

System for drying and burning viscous aqueous liquors which contain organics

Abstract: Sawdust is mixed with partially concentrated black liquor from pulp manufacture. The sawdust, coated with the solids of the black liquor, is dried by heated air. The sawdust, coated with organic and inorganic black liquor solids, is fed to the hearth of a chemical recovery boiler. Combustion of the char formed on the boiler hearth produces heat which causes additional organic material to pyrolize. The inorganic material combines to form molten smelt. The moisture-laden, heated air from the dryer is introduced into the boiler with the secondary air and the smelt is tapped off into an aqueous solution to form green liquor.

Fertilizer from the oxidative ammoniation of sawdust

Abstract: Pine sawdust was reacted with air and ammonia over a range of temperature to incorporate nitrogen. The resulting solids contained large amounts of nitrogen in organically bonded forms. Increasing reaction time and temperature increased the nitrogen content of the product. Flow rate of air and ammonia had less effect. Maximum nitrogen content, 27% was obtained after 4 hours at 320 degrees C.

Device for the transformation of ligneous waste materials, particularly of wood waste, into combustible granules of small diameters, and granules obtained with this device

Abstract: 1. An installation for converting ligneous waste, particularly wood waste, into combustible granulated products of small diameter, consisting essentially of a boiler (1, 31) fed from a silo (2, 43) by means of a proportioning bin connected to an extractor disposed in the bottom of the silo (2, 43) and of a drier (5, 34) fed by the combustion gases of the boiler (1, 31), characterised in that the silo (2, 43) for feeding the boiler is a crushed bark silo, in that the drier (5, 34) is a static and mechanical drier (5) fed by the cooling air of the boiler (1) and with damp sawdust from a damp sawdust silo (7) or a three-path horizontal drying drum (34) connected to the boiler (31), by means of a hot-air generator (32) extended by a settling chamber (33), and which is fed with bark and damp wood waste in the form of micro-platelets, and with damp sawdust by means of a conveying and proportioning unit (35) connected to a silo (36) for bark and damp wood waste in the form of micro-platelets, and for damp sawdust, in separating cyclone (11, 37) connected to the outlet of the drier (5, 34) returning to the free atmosphere the drying air laden with residual water vapour from the dehydration, as well as the fumes, at its upper portion, and in that the lower portion of the cyclone (11, 37) feeds, either directly a dry sawdust silo (15) connected by means of a proportioning bin, of a grinder (18) and of a mixer (19) to a granulating press (20) or a rotary lock (39) for feeding a shaking screen (40) for separating the sawdust and the micro-platelets, the outlets (41, 42) for which are connected, on the one hand, for the waste of large granulometry, to the silo (43) feeding the firebox of the boiler and, on the other hand, for the sawdust, after passage through a continuous humidity checking apparatus, to a dry sawdust silo (44) connected to the granulating press (20), the outlet of which leads into a cooling-screening device (21) discharging the granulated product with the desired dimensions into a bucket elevator (22), and of storage silos (24) for said granulated products connected to the elevator by a distribution hopper (23).

Digestibility of sawdust estimated by the nylon bag technique

Abstract: Summary-The digestibilities of sawdust from one hardwood species, Spotted Gum (Eucalyptus maculata), and two softwood species, Hoop Pine (Araucaria cunninghamii) and Pinus pinaster, were estimated by the nylon bag technique. The dry matter digestibilities were 8.3, 1.7 and 4.4%, respectively. Lignin concentration was possibly a major factor affecting digestibility as the values were 16.4,32.3 and 27.8%, respectively. For each species the ruminal digestion was completed within 48 h. Sawdust and other wood products such as paper periodically attract attention as a potential source of energy for ruminants. Because untreated sawdust is never the sole component of an animal's diet, its digestibility and that of its constituent chemical fractions cannot be determined by conventional in vivo trials. Gulbransen (1977) measured the digestibility of untreated sawdust by the difference method. However, this technique suffers the disadvantage of the assumption that the addition of feed of unknown digestibility to a basal diet of known digestibility has no effect on the digestibility of the basal diet. This may be an invalid assumption with a low digestibility feed such as sawdust, which may alter the residence time of feed particles in the rumen, thereby changing the time available for microbial breakdown of the basal diet. The nylon bag technique has the advantage of not requiring that sawdust be the sole component of the diet. It also provides sufficient undigested residue to allow a number of chemical analyses to be carried out and allows estimation of the rate of degradation of test material in the rumen free from rate of passage considerations. This paper reports an experiment in which the nylon bag technique was employed to measure the digestibilities of sawdust from three species of tree.

Slide Area Stabilization with Sawdust and Bark Chips

Abstract: UNSTABLE embankments and slide areas have always been an expensive maintenance problem. The Mt. Baker-Snoqualmie National Forest has used sawdust and bark chips for replacing soil in unstable em-bankments. The substitution of sawdust reduces the unit weight by as much as 75 percent, thereby increasing the stability of the fill. Sealing the sawdust using emulsified asphalt will give a life expectancy of at least 15 yr. This application of a waste product appears to be a very economical solution to slide areas on secondary and low standard roads.

Gasification of oak sawdust, mesquite, corn stover and cotton gin trash in a countercurrent fluidized bed pilot reactor

Abstract: The Synthesis Gas From Manure (SGFM) process was designed to convert cattle feedlot manure to ammonia synthesis gas. Current work is aimed at using any biomass feedstock to produce either medium-Btu gas or chemical feedstocks. This paper presents a comparison of the experimental results compiled on gasification of oak sawdust, corn stover, mesquite, and cotton gin treash in the SGFM pilot plant. The SGFM process is based on a countercurrent, fluidized bed reactor. In this system, biomass is fed to the top of the reactor resulting in the fresh feed being partially dried by direct contact with hot product gas prior to entering the reaction zone. A weighted comparison of the product gas, hydrocarbon, and hydrogen yields, gas quality, calorific value of product gas, percentage conversion of raw feed heating value to gas heating value, and operability of each feed indicated that oak sawdust was the best feedstock. (Refs. 7).

Simple techniques for basic bio-fuels

Abstract: Waste materials can be bundled (twigs, straw, hay, leaves) or made into briquettes (paper, sawdust, fibres, crop residues, etc.) as an energy resource. Elementary processing equipment is described and illustrated. Heat values are tabulated for a range of such fuels. (Refs. 3).

Apparatus and method for operating a brick kiln

Abstract: Heated waste gases are directed from the tunnel of a brick kiln into a dryer for effective drying of sawdust which is then fed from the dryer into a grinder which reduces the sawdust to finely divided wood fibers and then delivers the ground sawdust to a storage hopper. Apparatus is provided for directing an airstream from a source into and through each of a plurality of burner units positioned along the tunnel of the kiln and extending into the tunnel for generating the desired heat for treatment of the brick, and further, means are provided for feeding the dried ground sawdust from the storage hopper into the airstream in each of the burner units so that the airstream induces the flow of sawdust from the storage means into each of the burner units for the sawdust thus being utilized as the fuel for the burners.

Dehydration method for sludge

Abstract: PURPOSE:To dehydrate the sludge produced in high load microbe treatment at high speeds and produce cake of low moisture contents by adding sawdust and/or fiber dust to the sludge discharged from a waste water treating device utilizing microbes then adding a high polymer flocculant thereto. CONSTITUTION:Sawdust and/or fiber dust of 10-200 mesh grain sizes are added as a dehydration assitant to the excess sludge discharged from a waste water treating device utilizing microbes, and further a high polymer flocculant is added thereto to allow flocs to form. Thence, these flocs are dehydrated with a filter press, a vacuum dehydrator or centrifugal dehydrator, whereby cake of low moisture contents is obtained. The amount of addition of the sawdust and fiber dust is 20- 100% based on the weight of sludge solids, more preferably around 50%. The amount of addition of the high molecular flocculant is satisfactory if it is 0.2-0.5% based on the weight of sludge solids. Thereby, the sludge is solid-liquid separated continuously, efficiently and effectively.

Method of inducing solid combustibles to gas generators - involves forming material into pellets using binder as necessary to avoid clogging generator

Abstract: Anew method is used for introduction of solid combustible materials into gas generators etc. Normally such waste materials as wood shavings, sawdust can only be introduced in small quantities without clogging the machine. In this method' the material is mixed with a suitable binder and compressed into pellets. The pellets may typically have a dia. of between 30 and 80 mm, enabling easy handling while still presenting a reasonably high surface-to-volume ratio. Sawdust' straw, crushed sugar cane and other waste materials may be used in pellet form.

Catalytic cracking of heavy oil

Abstract: PURPOSE:To utilize an industrial waste and to obtain light oil, a lower olefin gas, etc., in high yield, by catalytic cracking of a heavy oil in the presence of a specific amount of powdered lignin as a catalyst at a high temperature. CONSTITUTION:A hydrocarbon heavy oil, e.g. crude oil from China, boiling at 300 deg.C or above is mixed with 50wt% or less, preferably 5-30wt%, of powdered lignin, e.g. an industrial waste from a paper mill, sawdust and a vegetable organic substance similar to the sawdust as a catalyst, alone or in combination. The mixture is then mixed with 1-100wt% (based on the organic catalyst) of an inorganic catalyst, e.g. zeolite or allophane if necessary, and subjected to catalytic cracking at 350 deg.C or above under pressure if necessary to give a mixed gas comprising large amounts of light oil and 3-4C olefins. EFFECT:Nascent hydrogen gas from the thermal decomposition of the organic catalyst stabilizes unstable by-products and produces the desulfurization effect. By- product carbon is deposited on the porous catalyst without attaching to the pipe wall.

Moisture evaporation apparatus

Abstract: PURPOSE:To prepare fertilizer or the like by evaporating a liquid to be treated economically in high efficiency through a method wherein a self-running type apparatus for sprinkling a treating liquid which also serves as a stirring device for a drying medium moving along a side wall of a fermentation tank containing the drying medium is provided and various apparatuses are enclosed in a house. CONSTITUTION:Sawdust or the like is scattered to form a layer as a drying medium in an evaporation and fermentation tank comprising a water-proof floor 1 embedding a warm water circulating pipe 4 and a side wall 3 encircling said floor 1. The saw dust layering operation is carried out by utilizing a self-running apparatus 15 for sprinkling the treating which serves also as a stirring device for a drying medium and letting said apparatus 15 run from an optional one side of the tank 1 by selecting a rotary direction of a stirring blade. Subsequently, warm water is circulated to the pipe 4 and air is injected from an air injecting pipe 9 above the floor 1 to start an air blower 29. In this condition, a liquid to be treated such as animal excretion or the like contained in a sewage tank 18 is sprinkled over the sawdust by the apparatus 15. Fermentation is promoted by adding bacteria to said sawdust and, moreover, because solar energy can be utilized, the treatment of the treating liq. is performed economically. The fermented sawdust is utilized as a fertilizer or a feedstuff.

Sawdust burner with automatic control system for feeding

Abstract: PURPOSE:To obtain a sawdust burner with an automatic control system for feeding which is effective in oil-saving by a method wherein dust lumbers waste (sawdust) is utilized as a heat source instead of oil and feeding of the sawdust is enabled to be controlled automatically. CONSTITUTION:Sawdust delivered by a duct 4 is diffused by a centrifugal separator 3 and is dropped into a silo 2, then, is pushed by a rotary vane 21 and is dropped through a wall plate 9, thereafter, is entered into a pipe 8. Further, the sawdust is converyed by a screw-conveyor 10 rotated by an electronical stepless speed change motor 13 and is blown into a combustion chamber 11 strongly by a fan 12. The sawdust, ignited and burnt, increases a heating power and a temperature of water in a boiler 25 is risen to a predetermined high temperature, then, a thermostat incorporated in a temperature detector 26 is operated to reduce a revolution of the electronical stepless speed change motor 13.

Steam gasification of wood in the presence of catalysts

Abstract: Catalytic steam gasification of wood, including sawdust, chipped forest slash, and mill shavings, is being investigated. Results of laboratory, process development unit (PDU), and feasibility studies illustrate attractive processes for conversion of wood to methanol and a substitute natural gas (SNG). Recent laboratory studies developed a long-lived alloy catalyst for generation of a methanol synthesis gas by steam gasification of wood. Modification of the PDU for operation at 10 atm (150 psia) is nearly complete. The modified PDU will be operated at the elevated pressure to confirm yields and design parameters used in process feasibility studies. Feasibility studies were completed on wood-to-methane (SNG) and wood-to-methanol plants with capacities of 2000 and 200 oven dried tons (1800 and 180 metric t) per day using catalytic gasification. The results showed that generation of methanol on the large scale is economically viable today while SNG generation is competitive with future prices.

Method for dehydration of sludge

Abstract: Waste sludge contg. cellulose of paper manufacturing plant is dehydrated efficiently by mixing 1-10 wt. % (on the basis of 80 wt.% water contg. sludge) dehydration accelerator such as rice hull, sawdust and the bark-milled finely. When the sludge is mixed with 1-10 wt. % rice hull and 40-50 wt. % bark, the content of water is decreased to 56.0 wt. %. (If the sludge is dehydrated independently, the content of water is to be 74.0 wt. %.)

Artificial fuel logs based on coal - contg. peat, wood waste, calcium aluminosilicate, wax and oil

Abstract: Fireplace logs comprise (a) 7-12% peat with a moisture content of 25-30%, (b) 7-10% wood shavings or sawdust, (c) 35-40% coal (pref. bituminous), (d) 5-10% expanded Ca aluminosilicate satd. with water, (e) 20-25 wt.% granulated paraffin wax or stearin, (f) 7-12% paraffin oil, (g) pine-needle oil, and (h) 5-10% of oxygen-donor salts, e.g. nitrates and/or borax. The logs are inexpensive to produce, easy to ignite, and burn for longer and give off more heat then natural logs. They burn with a crackling effect and a pleasant aroma without excessive smoking.

Method and device for sewage treatment

Abstract: PURPOSE:To obtain organic manure with good nutrition balance for a small number of days, by performing stirring and aeration while cultivating protozoans in sewage, and then by adding sawdust to the obtained sludge for fermentation. CONSTITUTION:Raw sewage crushed finely by crusher 3 is fed into sewage storage tank 1, where seed sludge containing protozoans, such as paramecia and vorticellae, is added for cultivation. In adjustment tank 4, its water is adjusted and while aeration is performed is aeration tanks 6 and 7, an aerobic digestion treatment is performed. Then, the sludge is separated into concentrated sludge, to which the sewage is added from sewage tank 14 and after dehydration, sawdust 16 is mixed. Then, this mixture is fermented in fermentation tanks 17 and 18 to obtain sawdust compost 19. This compost is granular and becomes valuable organic manure containing much protein.

Fire resistant goods prodn. esp. cardboard, sheets, or panels - from fibres such as wood pulp mixed with water, boron minerals, and acid

Abstract: The fibres are made into an aq slurry, to which boron minerals (I) and mineral acids are added, esp to obtain pH 15-3, esp 20 Lhe mixt is allowed to mature, and is then fed to a fleece mfg and dewatering machine; the fleece obtd is dried Minerals (I) pref contain Ca; and the mixt may also contain expanded- vermiculite, -clay, -oil shale, or perlite; and/or gypsum The water used to make the slurry is pref recirculated, and may contain fire retardants One fleece may be formed on top of another In an example, to make 1 tonne of wood fibre thermal insulation panels, 643 kg disintegrated wood and/or sawdust was wet milled, and then 240 kg colemanite (45% boron) added, plus H2SO4 to give pH 2-25 The mixt was left to mature, so pH 45-48 was obtd, and was diluted as required, then made into a fleece and dried to ca 5% residual moisture In a similar example, waste paper, sodium-cellulose, and colemanite were mixed with water and H2SO4

Competição entre processos de amadurecimento de manga

Abstract: Mangoes, cv. Imperial, were exposed, in post harvest, to the following methods of ripening: 1) sawdust burning; 2) alcohol vaporization; 3) calcium carbide (acetylene), 4) vapour of ethylene; and, 5) immersion in ethefon. All methods resulted in acceleration of ripening, when compared to controls. Calcium carbide, ethelene and ethefon were the best, methods. Alcohol vaporization also showed good results sawdust burning method showing low efficiency.