02114 Modification method of coal ash and application of modified coal ash

02114 Modification method of coal ash and application of modified coal ash

04 By-products related to fuels lmprovlng lightweight concrete with bottom ash 9ai02104 Nisnevich, M. Concr. Inr., 1997, 19, (12) 56-60. The paper ...

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04

By-products

related to fuels

lmprovlng lightweight concrete with bottom ash 9ai02104 Nisnevich, M. Concr. Inr., 1997, 19, (12) 56-60. The paper investigates the effect of fly ash volume on the porosity, density and strength of lightweight concrete made with portland cement, fly ash and coarse and fine aggregates of bottom ash. Lightweight concrete with decreased cement-fly ash paste porosity and increased concrete strength, through low cement content, could be made.

compacted in situ by rolling. Type-F and Type-C fly-ash are preferred. The final product aggregate has compressive strength ~2000 psi and is suitable for use as fill in concrete and pavements.

Injection powder as filler

9wo2112

9wo2105

molding of thermoplastics.

Anthracite

Hupfer, B. and Kretzschmar, B. KunstsrofJberater, 1997, 42, (l/2), 25-29. (In German) The paper investigates the injection moulding of polyolefin compounds containing 40-60% anthracite powder and the possibility of changing the material properties. The compound was processed on a conventional injection moulding machine using a standard plasticizer. Processing parameters slightly influenced the mechanical properties of the compound. Relatively low and isotropic shrinkage behaviour was displayed by the compound.

Kinetics of hydroprocessing cuum residues

98iO2106

of coal-derived va-

Wane. S. et al. Preor. Pao. Am. Chemical Sot., Div. Fuel Chem., 1997, 42, (l), Z-131. ’ ’ The reactivity of coal-derived residues varied widely towards breakdown into lower boiling products. High catalyst activity and solubilization appeared necessary for the conversion of these materials.

98102107

Manufacture of artificial aggregate from fly ash

Kawamoto, K. et al. Jpn. Kokai Tokkyo Koho JP 10 29,841 [98 29,841] (Cl. C04B18/08), 3 Feb 1998, Appl. 961186,450, 16 Jul 1996, 6 pp. (In Japanese) Mixtures of fly ash with bentonite and other materials at suitable ratios give a composition containing 20-80 wt% SiOr and 10-35 wt% CaO, pulverized, pelletized and fired to obtain artificial aggregate. The other materials are selected from, as a source of SiOZ, silica sand, potter’s clay, feldspar, kaolin, Kibushi clay, and incinerator ash and, as a CaO source, limestone, Ca(OH)z, and quicklime.

Manufacture of building blocks from coal combustion waste and related products

98lO2108

Weyand, T. E. et al. PCT Int. Appl. WO 98 01,404 (Cl. C04B28/02), 15 Jan 1998, US Appl. 674,699, 9 Jul 1996, 28 pp. Having a mineralogical crystal phase, the building blocks are manufactured by moulding a mixture containing coal combustion products, such as fly ash and bottom ash, as the major component, with a calciferous additive and water. The mixture is subsequently cured under a controlled pressure and temperature for a pre-determined time. The paper discloses the preferred ratios of fly ash to bottom components.

Manufacture of high-quality isotropic graphite from solvent-soluble fraction of coal powder

9wo2109

Stiller, A. H. et al. U.S. US 5.705139 (Cl. 423-445R; ClOC1/18), 6 Jan 1998, US Appl. 949,985, 24 Sep 1992, 8 pp. Cont. of US Ser. No.949,985, abandoned; Solvent extraction is used to process bituminous coal powder-the soluble organic fraction is recovered from the solution and heated for carbonizing. This produces isotropic calcined coke suitable for conventional manufacture of isotropic graphite not based on conventional petroleum coke. The coal powder is typically processed in N-Me pyrrolidone (I) or similar solvents to dissolve 25-80 wt% of the coal feed. The solids recovered from the solvent arc heated at 400-6Oo”C to obtain green coke, then calcined at 900-13OO”C, and milled to coke powder by the final heat treatment at 280035OO”C, which can be used for pitch-bonded preforms for the manufacture of graphite. The porous coke preforms are optionally impregnated with pitch for increased density prior to the final graphitization. Powdered bituminous coal containing 61.3% carbon and 26.4% ash was leached with refluxed I for 1 h at 202°C under N2 atmosphere, and the solution was processed to recover the dissolved organic fraction as the low-ash solids with 74.2% yield based on coal. The organic fraction was calcined and milled to obtain the coke powder containing 99.0% carbon, suitable for mixing with coal-tar pitch for manufacture of preforms processed by baking and graphitizing. The rod specimens extruded with diameter of 0.75 i;ches were graphitized at -2800°C and showed bulk d;nsity of 1.506 g/cm and thermal expansion coefficient axially at 4.3 x lo- /degree and transverse at 5.10 x lo- /degree near room temperature. 9wo2110

Manufacture of high-strength

lightweight aggre-

gates Ivkovich, D. P. U.S. US 5,704,972 (Cl. 106-710; C04B18/02), 6 Jan 1998, Appl. 787,605, 23 Jan 1997, 7 pp. A mixture containing fly ash 68-95, hydrated lime 2-10, and alkali metal hydroxide NaOH, 3-12, and adding water to the mixture at lo-25 wt%. The resulting slurry is compacted, rotated and heated in a rotary kiln to form pellets. The pellets are removed from the rotary kiln and they are allowed to hydrolyse and form a hard material that may be crushed and, optionally, screened to form an aggregate having a particular size or a range of sizes. The resulting slurry may alternatively be spread on a level surface and then

Manufacture of impregnating pitch from high-boiling fractions of coal tar

98/02lll Pity&r,

I. N.

Koks Khim., 1997, (8) 21-24.

Method for solidification use in concrete composition

(In Russian)

of incinerator ashes to

Tsutsui, T. and Tsutsui, M. Jpn. Kokai Tokkyo Koho JP 09,314,092 [97,314,092] (Cl. B09B3/00), 9 Dee 1997, Appl. 96/138,904, 31 May 1996, 9 pp. (In Japanese) The incinerator ashes containing AI/AI alloy with alkali aqueous solution are treated to form hydroxide of aluminium (alloy), then dewatered to obtain dewatered cake. Cement is then added for solidification and heavymetal stabilizing agent for immobilization of heavy metals.

Method of preparing phenolamlne resins by poly condensation of liquid products of coal thermal treatment with hexamethylenetetraamine

98102113

Kornejchuk, G. K. et al. Russ. RU 2,089,562 (Cl. C08G8/08), 10 Sep 1997, Appl. 95,113,865, 16 Aug 1995. From Izobreteniya 1997, (25), 259. (In Russian)

9wo2114 Modification method of coal ash and application of modified coal ash Maeda, K. et al. Jpn. Kokai Tokkyo Koho JP 09,290,234 [97,290,234] (Cl. B09B3/00), 11 Nov 1997, Appl. 96/126,308,24 Apr 1996, 5 pp. (In Japanese) The paper reports a method for modifying coal ash generated from coal combustion. It involves spray treating the coal ash with a spray apparatus in a furnace, which comprises spray burner, lance, utility controller, and powdered ash feeder, and jetting the coal ash with carrier gas through spray flame by the spray burner. The modified coal ash can be used to substitute the sand of concrete.

Non-destructive evaluation of fly ash-rich high9wo2115 performance concrete (HPC) Hwang, C. L. and Jann, I. Y. Proc. Int. Congr. Chem. Cem., IOth, 1997, 3, 3~021, 4 pp. Edited by Justnes, H., Amarkai AB, Goeteborg, Sweden. Containing a large amount of pozzolan, high-performance concrete (HCP) has been developed. Due to use of the densified mixture proportion algorithm (DMDA) and strict quality control, bleeding and segregation problems have disappeared. The strength at the designed age of 56 days could be predicted using non-destructive testing. Large variation of pulse velocity and electric resistivity showed the deficiency in the conventional rich-mix concrete, and were harmful to long-term durability.

9WO2116 One powder-type polymer cement compositions for semi-resilient pavements Anazawa, M. er al. Jpn. Kokai Tokkyo Koho JP 10 01,345 [98 01,345] (Cl. C04B28/02), 6 Jan 1998, Appl. 96/156,615, 18 Jun 1996, 6 pp. (In Japanese) Cement, limestone micropowder, silica sand, emulsifiable polymer powder and powdered additives comprise the compositions. They may contain fly ash or blast furnace slag instead of limestone micropowder, limestone aggregate instead of silica sand, or powdered asphalt instead of emulsifiable polymer powder. The compositions have high fluidity and good white colour.

9wo2117 The oxldative reactivity of coal chars in relation to their structure

Chan, M.-L. et al. Prepr. Pap. Am. Chemical Sot., Div. Fuel Chem., 1997, 42, (1) 222-226. The internal surface area of highly porous carbons can increase as a function of conversion during oxidation due to pore growth and the opening up of sealed internal pores or cavities. Consequently, rate expressions for carbon oxidation are more accurately described in terms of the intrinsic reactivity, where differences in surface area and porosity are accounted for. The oxidative reactivity of coal chars is complicated by a number of different factors which are explored in this paper. These include: (1) the development of the pore structure during devolatilization of the coal, (2) the ash content and its distribution in the carbon matrix, (3) the hydrogen and nitrogen functional groups present on the solid matrix and the interrelation with volatile species present and (4) the graphitic nature of the carbon surface and the active surface area available for reaction.

9WO2116 mass tars

Phenol-formaldehyde

resin substitutes from bio-

Himmelblau, D. A. Proc. Biomass Conf. Am.: Energy, Environ., Agric. Ind., Znd, 1995, 1141-1150. Discusses the production of adhesive resins from biomass to reduce reliance on raw materials derived from commodity petrochemicals and to lower resin costs. A simple fluidized-bed reactor system can be used to produce tars that can substitute for a major portion of the phenol and formaldehyde in phenol-formaldehyde (PF) resin adhesives. This can be done in an airfluidized, single-bed reactor; no inert gas or dual-bed system is required. A wide range of phenols, aldehydes and other compounds capable of polymerization are produced. Any wood waste larger than sander dust is

Fuel and Energy Abstracts

May 1998

191