00953 Applications of combustion technologies of micropulverized coal

08

familiarity is a critical link in predicting interest toward photovoltaics for the non-adopter group, while technical knowledge figures much more prominently for the adopters. Photovoltaics have been heralded widely as the future of electricity generation, and commercialization efforts to date have over-emphasized factors that affect early adopters while ignoring softer influences that may incite non-adopters to invest. By invoking programmes that promote small scale experiments and risk reduction by following the lead of other successful trials, the chances of long term success are much improved.

00100946 materials

Manufacture

Kosaka, H. et al. FACT (Am. Sot. Mech. Eng.). 1998, 22, (Proceedings of the 1998 International Joint Power Generation Conference, Vol. I. 1998), 483-488. Entrained bed and fixed pebble bed are combined to form a new concept in coal and wastes gasifiers. The main features of this pebble bed gasifier are its high efficiency in molten slag capture and gasification. as well as its compactness. Coal and refuse derived fuel (RDF) combustion experiments using the pebble bed gasifier demonstrated high efficiency capture and continuous extraction of molten slag. Further, complete char combustion with extra ordinarily short residence time of pulverized coal and crushed RDF at the temperature level of about 1500” within the pebble bed was achieved. Durability tests in a high temperature electric furnace has shown that high density alumina is a good candidate for pebble material.

OOlOO946 Kannada

Hydroelectric resource assessment District, Karnataka State, India

of cement

using combustible

waste

Nakajima, M. Jpn. Kokai Tokkyo Koho JP 11 60,296 [99 60,296], (Cl. CO4B7/44), 2 Mar 1999. Appl. 971209,525, 4 Aug 1997. 5 pp. (In Japanese) Cement can he manufactured using comhustihle waste materials. The process involves volume-reduced solid materials of combustible waste materials such as compacted waste plastics heing crushed to
Method and device for gasification

00/00949

00l00945 High efficiency power generation from coal and wastes utilizing high temperature air combustion technology. (Part I: Performance of pebble bed gasifier for coal and wastes)

Steam raising (boiler operation/design)

of waste

materials Marschner, S. and Halang, S. Ger. Offen. DE 19,735.153. (Cl. CIOJ3/08), 18 Feb 1999, Appl. 19,7X,153, 13 Aug 1997. IO pp. (In German) Wastes such as municipal refuse and PVC arc treated by incineration in a molten rotating slag hath. Waste gases, such as hydrochloric acid and fuel gas, are collecred and recycled, and the excess slag i\ removed. 00100950 Oil conversion technology from waste plastics Matsudori, H. Sarl(No /o Kankyo. 199X. 27. (I I ). 9X-100. (In Japanese) Described in this paper is a pilot plant for oil conversion from waste plastics. The discussion focuses on various stages of pre-treatment and thermal decomposition systems. The procedures u\ed to process the waste plastics to obtain flake-or particle-shaped feedstock for oil conversion process, include magnetic separation, grinding and air-assisted gravity separation. For plastics containing PVC, the gas produced during thermal decomposition process is first introduced to a dechlorination column before it is fed into the catalytic reforming column. The system is capable of converting general municipal wastes to clean. high quality fuel oil without pollution.

in Uttara

Ramachandra. T. V. et al. J. Cleaner Producfion, 1999, 7. (3). 195-211. The amount of power available at a given site is decided by the volumetric flow of water and the hydraulic head or water pressure. In hydro schemes, the turbines that drive the electricity generators are directly powered either from a reservoir or the ‘run of the river’. The large schemes may include a water storage reservoir providing daily or seasonal storage to match the production with demand for electricity. These schemes have been producing power in Karnataka for many years, with the first hydroelectric station built in 1942. The majority of them are in Uttara Kannada district. Due to environmental constraints, further construction of storage reservoirs is limited and attention has been focussed towards developing environmentally friendly small-scale hydro schemes to cater for the needs of the region. In this paper, potential schemes carried out in the streams of Bedthi and Aghnashini river basins in Uttara Kannada district of Western Ghats are discussed. Five feasible sites are assessed based on stream gauging carried out for a period of 18 months. Computations of discharge on empirical/ rational method based on 90 years of precipitation data and the subsequent power and energy values computed are in conformity with the power calculations based on stream gauging. It is estimated that, if all streams are harnessed for energy, electricity generated would be in the order of 720 and 510 million units in Bedthi and Aghnashini basins. respectively. This exercise provides insight into meeting the regional energy requirement like harnessing hydro power in a through integrated approaches, decentralized way during the monsoon season, and meeting lean season requirements through small storage, solar or other thermal options. Net energy analyses incorporating biomass energy lost in submergence show that maximization in net energy at a site is possible if the hydroelectric generation capacity is adjusted according to the seasonal variations in the river’s water discharge.

00/00951

in gasification

Power geperation by using gas and steam obtained of waste plastics and melting of incinerator

Kajihata. Y. et a/. Jpn. Kokai Tokkyo Koho JP I I 29,779 [99 29,779] (Cl. ClOJ3/00), 2 Feh 1999. Appl. 971200.X77, 9 Jul 1997. 7 pp. (In Japanese) The title process is described in this paper. Waste incinerator ash and waste plastic are fed into apparatus which gai;ifies the waste plastics and melts the ash. The process takes place at a temperature higher than the m.p. of the ash to decomposes dioxins in the ash, to ohtain fused slag, for elution prevention of heavy metals and to obtain gas from which corrosive components are removed. Sensible heat generated by combustion of the purified gas is used to superheat the steam generated at the downstream of waste incineration furnace, this in turn is used to drive a steam turbine for power generation. In this process power generation is carried out efficiently without generation of toxic gas. 00/00952 Use of industrial wastes in cement production Kopeliovich. V. M. er al. Ttement, 1998. (3), 35-39. (In Russian) This review is concerned with the experience? encountered by Ukrainian cement producers in utilizing industrial waste for the process. The effectiveness of specific types of waste as alternative fuels is demonstrated.

08

STEAM RAISING Boiler Operation/Design

00/00947 solvents

Liquefaction of scrap automobile and solvent mixes

tyres in different

Money, D. M. and Harrison, G. Fuel, 1999, 78, (14), 1729-1736. Tyre crumb samples from two sources, one UK and one Spanish, were liquefied using a process derived recycle solvent (PDRS) or tyre pyrolysis oil (TPO) or a mixture of the two solvents. For PDRS, experiments were carried out at different temperatures (360, 380, 400°C) and for different times (4OO”C, I or 2 h). For TPO and mixed solvent systems experiments were carried out for 1 h at 360 and 380°C only. Dissolutions were calculated as dichloromethane solubles (DCMS) and tetrahydrofuran solubles (THFS). The DCMS material from experiments at 360 and 380°C with either PDRS or TPO as solvent were subjected to hydrocracking using sulfided NiMo as catalyst. Conversions in the hydrocracking experiments were calculated by quantitative gas chromatography using biphenyl, acenapthene and fluorene as compounds to mark specific boiling point ranges. Experiments in PDRS showed effective dissolution even at the mildest of conditions. Adsorption of oils by carbon black caused problems, necessitating long filtration times and extensive extraction to remove adsorbed oil. Dissolution in TPO was lower and the appearance of retrograde reaction was apparent because of the lower H-donor content but problems with adsorption of oil were not as great, and values similar to those for PDRS were achieved when NiMo catalyst and HZ pressure were introduced. Conversions in the hydrocracking experiments were higher for the TPO extracts, suggesting some breakdown of the TPO itself. For the experiments with PDRS and TPO mixtures, the addition of up to 25 wt% TPO did not reduce the extent of dissolution compared with PDRS alone.

00100953 pulverized

Applications coal

of combustion

technologies

of micro-

Nakamura, M. et al. IHI Eng. Rev., 1999, 32, (l), 7-12. Normally, for combustion in boilers, coal is pulverized to 40-50 ,Lrn mean particle diameter. However, combustion of micro-pulverized coal of -20 ,hrn mean particle diameter achieves decreased NO, emissions and unburnt combustibles, and makes lower excess air ratio operation possible. These effects of micro-pulverized coal combustion were confirmed at the Hekinan Thermal Power Station No.3 Unit of Chubu Electric Power Co. Inc. It has been found, based on the results of economic evaluation, micro-pulverized coal combustion also reduces running costs of the unit. In conclusion, the pulverizer for micro-pulverized coal in a domestic industrial boiler has achieved good performance for the fineness of pulverized coal and capacity. 00/00954 Ash chemistry firing in utility boilers

aspects

of straw and coal-straw

co-

Frandsen, Flemming J. et al. Proc. Ann. Int. Pittsburgh Coal Co&, 1998, 15, 638-651. Deposits formed in straw-fired grate-boilers were shown to contain wt%) and KCI-coated Ca-Si-rich significant amounts of KCI (40-80 particles. CFB co-firing of straw and coal caused deposits to form in the convective pass containing predominantly KzS04 (50-60 wt%) with small quantities of KCI close to the metal surface. In pulverized coal-straw cofired boilers, deposits almost free of KCI were detected. The majority of the

Fuel and Energy Abstracts

March 2000

105