Fraction Of Slurry Research Articles

Effect of chip spacing in a multichip module on the heat transfer for paraffin slurry flow

The experiments were conducted by using water and paraffin slurry to investigate the effect of a chip spacing in the multichip module on the cooling characteristics from an in-line 4 × 3 array of discrete heat sources which were flush mounted on the top wall of a channel, The experimental parameters were chip spacing in a multichip module, heat flux of simulated VLSI chip, mass fraction of paraffin slurry, and channel Reynolds number. The removable heat flux at the same chip surface temperature decreased as the chip spacing decreased at the first and fourth rows. The local heat transfer coefficients for the paraffin slurry were larger than those for water, and the chip spacing on the local heat transfer coefficients for paraffin slurry influenced less than that for water. The enhancement factor for paraffin slurry showed the largest value at a mass fraction of 5% regardless of the chip spacing, and the enhancement factors increased as the chip spacing decreased. This means that the paraffin slurry is more effective than water for cooling of the highly integrated multichip module.

Effect of the aspect ratio of rectangular channels on the heat transfer and hydrodynamics of paraffin slurry flow

The objective of the present study was to investigate the effect of the aspect ratio of rectangular channels on the cooling characteristics of paraffin slurry flow with a linear array of discrete heat sources. Four key experimental parameters were the aspect ratio of the rectangular channel, the mass fraction of paraffin slurry, the heat flux of simulated VLSI chips, and the channel Reynolds number. The influence of the aspect ratio of the rectangular channel on the local heat transfer coefficients for both water and paraffin slurry at a heat flux of 40 W cm −2 was greater than at a low heat flux. The paraffin slurry with a mass fraction of 5% showed the most efficient cooling performance in a rectangular channel with an aspect ratio of 0.20 regardless of the heat flux and the channel Reynolds number.

Experimental study on the application of paraffin slurry to high density electronic package cooling

Experiments were performed by using water and paraffin slurry to investigate thermal characteristics from a test multichip module. The parameters were the mass fraction of paraffin slurry (0, 2.5, 5, 7.5%), heat flux (10, 20, 30, 40 W/cm2) and channel Reynolds numbers. The size of paraffin slurry particles was within 10–40 μm. The local heat transfer coefficients for the paraffin slurry were larger than those for water. Thermally fully developed conditions were observed after the third or fourth row. The paraffin slurry with a mass fraction of 5% showed the most efficient cooling performance when the heat transfer and the pressure drop in the test section were considered simultaneously. A new correlation for the water and the paraffin slurry with a mass fraction of 5% was obtained for a channel Reynolds number over 5300.

Liquid cooling for a multichip module using Fluorinert liquid and paraffin slurry

The objective of the present study was to investigate the effect of phase change material on heat transfer enhancement in a multichip module application. The parameters studied in the present study include the mass fraction of paraffin slurry, the heat flux of simulated VLSI chips and channel Reynolds numbers. The size of paraffin slurry particles was within 10–40 μm. The local heat transfer coefficients for the paraffin slurry were larger than those for water. The paraffin slurry showed an effective cooling performance at high heat fluxes. The paraffin slurry with a mass fraction of 5% showed the most efficient cooling performance when the heat transfer and the pressure drop in the test section were considered simultaneously. The present experimental data at the fourth and sixth rows gave an excellent agreement with the values predicted by the Malina and Sparrow’s correlation, and a new empirical correlation for the water and paraffin slurry with a mass fraction of 5% was proposed at the first and sixth rows for a channel Reynolds number over 3000.

Convective Heat Transfer from a Multichip Module with Different Chip Spaces to PCM Slurry Flow in a Rectangular Channel.

The objective of the present study was to investigate the effect of a chip spacing in a multichip module on the cooling characteristics of phase change material slurry. The experimental parameters were chip spacing in a multichip module, heat flux of simulated VLSI chip, mass fraction of paraffin slurry, and channel Reynold number. The removable that flux at the same chip surface temperature decreased as the chip spacing decreased. The local heat transfer coefficients for the parafin slurry were larger than those for water, and the chip spacing on the local heat transfer coefficient for paraffin slurry influenced less than that for water. The enhancement factor for the paraffin slurry showed the largest value at a mass fraction of 5% rregardless of the chip spacing, and the enhancement factors increased as the chip spacing decrased. This means that the paraffin slurry is more effective than water for cooling of the highly integrated multichip module.

Effect of natural zeolite (clinoptilolite) on microbial decomposition processes in stored pig-slurry solids.

The solid fraction (SF) of pig slurry obtained in the first stage of aerobic slurry treatment was amended with 1 and 2% zeolite (clinoptilolite) and stored for 12 weeks under anaerobic conditions or with turning after 3 and 6 weeks of storage. In addition to that SF was mixed with 2% zeolite, 50% (V/V) sawdust, and both sawdust and zeolite, and stored for 6 weeks with turning after 1 and 3 weeks. Plate counts of psychrophilic, mesophilic, coliform and fecal coliform bacteria, determined during the storage, corresponded to the development of temperature in the core of the substrates. An effect of amendment of SF with zeolite and sawdust on plate counts of selected bacteria was observed, dependent on the zeolite dose. The thermophilic phase was not reached in any of the investigated substrates. The populations of fecal coliforms in the substrate amended with 1% zeolite and turned after 3 and 6 weeks decreased after 11 weeks down to 500 CFU/g substrate.

Investigation of Slime and Slurry in Cast-in-Place Concrete Piles by Resistivity Method

ABSTRACT Cast-in-place concrete piles are made by placing concrete into slurry that fills an excavated hole, and where appropriate control of the physical properties of slime and slurry is necessary. Electric resistivity of suspension generally depends on the content of the suspended substance, so that physical properties such as density, sand fraction and funnel viscosity of slurry and sand fraction of slime, are closely related to resistivity of slurry and slime. In order to control these physical properties, we must measure their depth distributions in excavated holes. Measurement of resistivity in excavated holes continuously by depth is relatively easy, so we attempted to obtain information on physical properties of slurry and slime by measuring vertical distributions of resistivity. Relationships between the resistivity and physical properties of slime and slurry were determined in the laboratory test, and the vertical resistivity distribution of the slime and the slurry in the hole of a cast-in-place pile at excavation was also studied with a sensor capable of recording in-situ resistivity continuously. As a result, it was found that changes of resistivity were widely affected by the bentonite content of slurry and the sedimentation thickness of slime can be estimated with satisfactory precision by the vertical resistivity distribution (depth profile of resistivity) in an excavated hole. The resistivity method can be an effective, promising control method for the physical properties of slurry when the relationship between resistivity and the properties is quantitatively determined.

Kinetic study of the anaerobic digestion of the solid fraction of piggery slurries

This work deals with the determination of a kinetic model in an anaerobic digestion process. It is applied to the organic stabilization of the solid fraction of piggery slurry. The substratum results after filtering the farm wastewaters through a 1 mm mesh hydraulic sieve. Two pilot scale reactors were used, one digester was working in layered way — without agitation — and other was mixed with a stirrer. The experiments were carried out in a discontinuous process, 60 days hydraulic retention time, in the mesophilic interval (35°C). Average influent concentration was 68 and 97 g l −1 COD respectively for the non-stirred and stirred reactor, whereas the achieved reduction was 61 and 65%. Organic loading rates were 0.80 and 1.45 K VS m −3 d −1 . Specific biogas output was more efficient in the stirred reactor than in the stratified one. Several kinetic models were tried out in order to represent the methane production. A first order kinetic model applied in two stages was finally adapted for both reactors. The first stage presented the microbial growing as the limiting step, whereas the second stage was limited by the substratum availability. The effect of mixing on the kinetic parameters was analyzed. Significant differences were attained in the coefficients, thus K was 0.048 and 0.75 d −1 respectively for the non-stirred and stirred reactor.

The Use of Ozone to reduce the Concentration of Malodorous Metabolites in Swine Manure Slurry

A pilot-scale ozonation system was constructed and operated to reduce the malodours emanating from fresh and stored swine manure slurry. The concentrations of the malodorous bacterial metabolites (phenol,p-cresol,p-ethylphenol and skatole) found in the liquid fraction of the manure slurry were found to increase during three weeks of storage. The fresh and stored manure slurry was ozonated at dosages of 0·25, 0·5, 0·75 and 1·0 g/l. Ozonation eliminated these metabolites from the manure slurry. On the contrary, no useful decrease in the concentration of all the above metabolites was observed after treatment with either nitrogen or oxygen. The odour intensity of the manure slurry was also significantly reduced (P<0·05) after ozonation at a dosage of 0·5 g/l. In contrast, neither stripping with nitrogen nor oxidation using oxygen had a significant effect on the odour acceptability of the mature. The use of hydrogen peroxide and ozone did not offer additional benefit over that obtained with ozone alone. Within the range of 14–25°C, temperature had no effect on the efficiency of ozonation. The ozonated manure did not regain its original malodour after one month of storage subsequent to ozonation.

Complete conversion of brown coal into distillate

The conditions for complete conversion of Victorian brown coal were investigated with an iron–sulfur catalyst in a continuous reactor system consisting of three stirred tank reactors in series. The coal was found to be completely converted into distillate (b.p.<420°C) when the gas flow rate (GFR) through the reactors was increased and the slurry-feed rate was reduced at a temperature of 450°C and a pressure of 18.6 MPa. An analysis of the composition of the liquid in the reactors under liquefaction conditions confirmed that the increase in GFR markedly enhanced the stripping of the solvent fraction in the feed slurry and the lighter fraction derived from the coal, resulting in marked increases in the actual residence time (θ RT) of the liquid consisting of the concentrated catalyst and heavy fraction. The stripping effect markedly enhanced liquefaction reactions, thus providing a higher distillate yield. However, the GFR effect was gradually saturated as the liquid remaining in the reactors (reactor liquid) became heavier with the increase in the GFR. The extension of nominal residence time (defined by the ratio of slurry-feed rate to reactor volume, θ NT) from reduction of the slurry feed rate was found to be effective in extending the GFR effects under a high GFR condition, resulting in the complete conversion of the coal. In addition, the stripping of the solvent by the increased GFR was also found to be more enhanced at 18.6 MPa than that at 14.7 MPa although its vaporization was suppressed at a higher pressure. This is due to the heavy fraction in the reactor liquid being more hydrogenated over the concentrated catalyst at a higher hydrogen pressure. However, the dependencies of the conversion rate of the heavy fraction on θ RT were almost the same for both 14.7 and 18.6 MPa. These results suggested that a complete conversion of the coal could be achieved at 14.7 MPa by using a heavier solvent.

Injection of pig slurry and its effects on dynamics of nitrogen and carbon in a loamy soil unter laboratory conditions

Dynamics of nitrogen (N) and carbon (C) were investigated in a loamy soil amended or injected with pig slurry. Treatments were with or without acetylene C2H2 (which is assumed to inhibit reduction of nitrous oxide (N2O) to dinitrogen (N2), and soil cores were conditioned for 15 days at 25°C while pH, production of CO2 and N2O, ammonia (NH3) emission and (nitrate) (NO3 –) and (ammonium) (NH4 +) concentrations were monitored. There was no significant difference in CO2 production between the injected and surface applied pig slurry treatments, and within 15 days ca. 5% of the C applied had been mineralized, if no priming effect was assumed. Neither the production of N2O nor the total gaseous production of the denitrification process (N2O plus N2) were affected by the way the pig slurry was added to the soil. NH3 volatilization, however, decreased by 90% when pig slurry was injected. The addition of C2H2 significantly increased the CO2 production and the concentration of NH4 +, but significantly decreased the concentration of NO3 –. It was concluded that the injection of pig slurry to a dry soil was an acceptable alternative to its application to the soil surface, as not only was NH3 volatilization reduced, but the production of N2O and N2 through denitrification was not stimulated. It is also suggested that the composition of the organic C fraction in the pig slurry, most likely the concentration of fatty acids, had an important effect on the dynamics of N and C in the soil.

Separation of Liquid Pig Manure by Flocculation and Ion Exchange Part 1: Laboratory Experiments

Abstract A method of treating pig manure is described, such that the necessary storage volume is reduced to 25–30% of the original volume. The manure is separated into a water fraction with a low content of dry matter and nutrients, and into a slurry fraction which contains most of the dry matter and nutrients. The water fraction can be purified to appear like pure water with a desired nitrogen concentration. The separation is made by flocculation, a process whereby a flocculation agent collects the organic matter in the liquid manure into bigger particles, which causes them to sink. The experiments showed that it is pos- sible to flocculate the volatile solids in 14 d old pig manure. For this purpose, a dosing of 0·2% of the clay mineral bentonite was sufficient to obtain adequate sedimentation. The liquid fraction can be purified by ion exchange with clinoptillolite or glauconite. It is possible to reach as low a content of ammonia as is wanted with an appropriate processing time.

Separation of Liquid Pig Manure by Flocculation and Ion Exchange Part 2: Pilot-Scale System

Abstract This paper reports the function and working results from a pilot plant in which liquid pig manure was flocculated with Geko-bentonite. The supernatant was irrigated on agricultural land throughout the year, but in the wintertime, only after ion exchange of ammonium with Agrolith. Earlier laboratory experiments showed that it is possible to purify the liquid to exactly the concentration wanted, although higher purity costs more. Hence, it is possible to use the method according to the legislation of individual countries to spray or irrigate the liquid onto fields. The thicker slurry fraction must be stored and treated as ordinary liquid manure. In order to maintain ability for pumping, the treatment should be stopped at approximately 12% dry-matter content, which represents a concentration of the liquid manure to approximately one-quarter to one-third of the original volume.

Preparing hydroxyapatite powders with controlled morphology

We developed a synthesis method for hydroxyapatite particles with different morphologies. The process involved chemical precipitation and spray drying, which produced spherical, agglomerated hydroxyapatite granules with controlled particle sizes and structures. These granules contained nanoparticles with an average crystalline size of about 10 nm. We controlled the morphologies of the granules by adjusting the spray-drying conditions, such as the volume fraction of feed slurry and the atomization pressure. The spray-dried granules were doughnut shapes, solid spheres, or hollow spheres, and their sizes were controlled by varying the atomization pressure and the concentration of the feed slurry.

Availability of manure slurry ammonium for corn using 15N-labelled (NH4)2SO4

The NH4+ fraction of animal manure slurry is often considered to be as available as fertilizer N to a crop; however, immobilization and losses via denitrification and NH3 volatilization may be higher in manured than in fertilized soil. The apparent N recovery and the 15N recovery methods were used for corn (Zea mays L.) grown in soil amended with dairy cattle slurry and NH4+ fertilizer to determine the source of the N taken up by corn plants. Manure slurry or (NH4)2SO4 fertilizer were applied at rates equivalent to 100 kg NH4+–N ha−1 in the greenhouse and the field. In the greenhouse, the apparent NH4+–N uptake by corn was 76 and 85% with animal manure slurries and NH4+ fertilizer, respectively. In the field, apparent N recovery of NH4+ from dairy cattle slurry and (NH4)2SO4 was 43 and 58%, respectively, whereas 15N recovery from the same treatments was 15 and 29%, respectively. The lower 15N recovery values compared with the apparent recovery values suggest that mineralization-immobilization turnover (MIT) occurred, and that MIT was greater in manured soil than in fertilized soil. A laboratory incubation study showed greater microbial biomass and more 15N immobilization in soil amended with dairy cattle slurry than in soil amended with fertilizer. Key words: Animal manure slurry, nitrogen, corn, N recovery, 15N microplots

Concentrations of malodorous compounds in swine wastes during storage

Abstract A study was undertaken to examine the effect of storage temperature on the malodour of swine slurry. Two storage temperatures were tested, ambient temperature (22–25°C) and 4°C. The effects of the storage on both the separated solids from the slurry and on the filtered slurry were included so as to ascertain which fraction of the slurry contained the major portion of malodorous compounds. The process was monitored by using a static headspace sampling gas Chromatograph (HS‐GC) technique which recorded the changes in the concentrations of the major malodorous compounds in swine slurry, volatile fatty acids, phenols and indoles. Results showed the effect of temperature on the storage of slurry, filtrate and solids to be significant in the initial 40 days. They also revealed that the malodorous compounds were primarily to be found in the soluble fraction of swine slurry. An initial accumulation and later depletion of the VFAs, phenols and indoles in the slurry, filtrate and solids indicated that the ...

Decomposition of the fibrous fraction of fermented slurry. Chemical reactions, collection of ammonia, and storage of the compost

Abstract Chemical analyses of the fibrous fraction of fermented slurry were performed before and after decomposition of the material. The pH in the fresh fibrous fraction was 8.7 and a smell of ammonia indicated great losses of nitrogen due to ammonia volatilization. By drying the fibrous fraction half the nitrogen content volatilized as ammonia. By decomposing the fibrous fraction half the nitrogen content volatilized and more than half the organic matter decomposed. Even then the compost was not stable for storage. The fibrous structure disintegrated whereby the evaporation of water attached to the organic matter was more or less impeded. The percentage of dry matter decreased and water containing plant nutrients leached from the pile. It is recommended to dry the fresh fibrous material and collect the ammonia volatilizing during drying. The dried fibrous material should then be used as mulch and spread on the soil surface in spring in order to protect the crumb structure of the soil against disintegration by heavy rain. Because of high solubility the content of potassium, magnesium, and phosphorus will still be satisfactory.

Study of olivines in the weathered crust of the kovdorsk massive as raw materials for refractories

A reduction in the magnesia concentration is due to the increase in the contents of AI203 and P2Os. At the same time we note a direct link between the MgO content and the amounts of CaO, FeO, Fe203, and SiO 2. An increase in the Fe0 content is accompanied by a reduction in the Fe203 content. These variations and also the relationships between them are determined by the mineral composition of the ore, as shown in Table 2 (contents of apatite and nepheline are stated after recalculation from the results of chemical analysis of samples, expressed as P20s and A1203; and the amounts of the remaining minerals are shown according to microscopic data). The main mineral is olivine which is taken to be a member of a continuous series of solid solutions formed by forsterite, Mg2SiO 4, and fayalite, PemSi0~. However, in fact, its composition is much more complex. According to chemical analysis data, the olivine contains (mass): 45.5-46.5% MgO, 7.2-8.9% FeO, 40.5-41.5% Si02, 0.2-2.2% CaO, 0.4-0.5% M_nO, 2.1-4.4% Fe203. The olivine grains are coated with a thin brittle film, yellow in color, which probably consists of serpentine [3], and is hydrated in the slurry fractions (<0.05 mm). According to DTA data, the slurry is dehydrated at II0-240~ mass loss Amcalc equals 3% (such a low Amcaic value is because the slurry, in addition to hydrated iron hydroxide Fe(OH)3"nH20, contains substantial amounts of serpentine and mica). This process is accompanied by blackening of the material, and the development of magnetic properties, probably due to the formation of magemite, ~-Fe=O 3. Thermodynamic studies were made of the possible ways that calcium and maganese could be introduced into the crystal lattice of olivine. Literature data on the thermodynamic properties of minerals was used [5, 6]. The reaction products were taken to be phases whose formation is most probable according to triangulation results in the CaO-Mg0-YeO-SiO 2 system [5], and also compounds existing in oxide systems containing Mn0 [7, 8]. Since olivines are members of a continuous series of solid solutions formed by forsterite, Mg2SiO ~, and fayaiite, Fe2Si04, we examined the reaction of these minerals with calcium and manganese oxides. Calcium oxide reacts with forsterite to form montichellite CaMgSiO~ and periclase, MgO.

Dewatering of fractionated peat slurry by ceramic microfilter and by filter press

The process where the fine fraction of peat slurry is dewatered by a special type of microfilter, and the coarse fraction by a filter press, was tested in bench scale. The effect of particle class, initial DS content, DS load, flocculants and their dosage were studied. In general, fractionation nearly doubled the capacity in the compression phase, but the final DS content did not rise significantly. The differences in the capacities between the particle classes were small in compression but high in microfiltration. The final DS contents were nearly equal in each particle class for both dewatering methods. Fractionation was not useful until the particle class was 500μm or bigger in microfiltration.

A test of a simple model of the acoustic velocity in marine sediments

A simple physical model is proposed for the dependence of the acoustic velocity of marine sediments on the porosity and lithology. The model is tested for clay-rich marine sediments using data from the Deep Sea Drilling Project, but has also been successfully used to calculate the acoustic velocity in consolidated and unconsolidated carbonate sediments. The model is a combination of the Wood [A. B. Wood, A Textbook of Sound (Macmillan, New York, 1941)] and Wyllie [Wyllie et al., Geophysics 21, 41–70 (1956)] (time average) models: Any medium may be thought of as composed of one fraction that is comparable to a slurry of particles in suspension and a second that consists of a rigid grain matrix. As the porosity decreases, so too does the fraction of slurry that makes up the sample. A slurry has essentially no shear strength, and thus the bulk compressibility is expressed as the weighted mean compressibility of the solid and fluid components. The rigid matrix velocity is determined using the time average equation. The variation of the grain (zero-porosity) velocity with lithology is similarly represented using the time average equation. The net bulk velocity is then taken to be the inverse of the weighted mean travel time for each of the component fractions. This approach could simplify the modeling of acoustic velocity variations given an independent measure of the porosity, or vice versa.