The CO2 gasification kinetics of olive residue

The CO2 gasification kinetics of olive residue

09 Combustion (burners, combustion systems) meohanisms of NO 03/01369 ImpWMWeof heterogen-us reduction duMg rdbwning,M pulvwfied coefs Zhong, B. et al...

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09 Combustion (burners, combustion systems) meohanisms of NO 03/01369 ImpWMWeof heterogen-us reduction duMg rdbwning,M pulvwfied coefs Zhong, B. et al. Ranshao Kexue Yu Jishu, 2002, 8, (1), 6-8. (In Chinese) Two kinds of lignite and bituminous coal, and their chars are selected as rebuming fuel in the experiment to study the NO reduction in the rebuming environment. The importance of heterogeneous mechanism on the NO reduction is analysed by comparing the difference in NO reduction of pulverized coal and its char. Experimental results indicate that lignites and their chars are effective reburning fuels. In the reburning zone using lignites as reburning fuels, the heterogeneous mechanisms may be an important contributor to NO reduction. The NO reduction can be catalysed metal oxide in coal. 03101370

Modeling char combustion with fractal pore

effects He, R. et al. Combustion Science and Technology, 2002, 174, (4), 19-37. The effect of char pores on char combustion was studied with fractal theory. The fractal properties of different char samples were derived from mercury porosimetry measurements. Gas diffusion in pores affects combustion in char pores and this diffusion is affected by the geometrical complexity of pores. To explore gas diffusion and combustion in fractal pores, a fractal geometrical factor p is defined with pore fractal dimensions and other fractal geometrical factors. It was found that both apparent activation energy and pre-exponential factor have linear relations with the factors p and the char combustion can be modelled with the fractal geometrical factor.

03/01371

Pollutant emissions from modern incinerators

Lima, R. and Bachmann,

R. T.

ht.

J. Environment

and Pollution, 2002,

18, (4). 336-346.

Emissions of dioxins are mainly from incinerators, domestic and industrial coal combustion, and traffic. However, the major public concern and research effort are associated with the emissions of organic micropollutants from waste incinerators. This paper gives a brief overview of the more recent research and development for the removal of dioxins and heavy metals from flue-gas streams. Special attention is devoted to the origin and control of emissions from incinerators. It appears that flue-gas cleaning systems in modern incinerators are very reliable in removing almost all polluting emissions from flue-gas streams. However, the fly ash residues generated pose a significant disposal problem, as they are enriched with heavy metals and organic micropollutants.

municipal solid waste through on-spot sampling and testing by classifying such waste into proper categories in the three main wastedischarging spots of Huanggu District, Shenyang. The investigation results indicate that the content of organic waste amounts to 90%, which shows an increase in proportion as compared with statistics of 1994. Thus, it can be concluded that it is necessary to change the old way of waste-disposal, otherwise it would be a failure in making a full re-use of all its energy potential. Secondly, a pyrolysis experiment was done in an externally heated fixed-bed furnace to test the typical components of the municipal solid waste with gas analysis. The authors analysed the rate of the gas production, the curve of the instantaneous gas production, the curve of the total gas production, the contrastive data of pyrolysis efficiency, the quotient of gas transform as well as the curve of the calorific value with different waste materials. It is essential to control the pyrolysis temperature in order to increase pyrolysis efficiency. Finally, it can be summarized that the properties of gas produced with different materials and in different conditions may influence the yield of pyrolysis gas components and calorific value. In addition, based on the apparent-kinetics model, the authors established a calculation model with the pyrolysis gas made by different particular materials. The curve of the experimental results helps the prediction of total gas production in a particular case of the municipal waste disposal.

03/01374 Slagging-bed electric-arc coal combustion In oxygen for power generation with thermal decomposition of water to hydrogen Schlueter, C. Ger. Offen. DE 10,112,873 (Cl. HOSB31/08), 19 Sep 2002, Appl. 10,112,873. (In German) Coal is burned under pressurized slagging-bed high-temperature combustion conditions in O2 in an electric arc furnace for steam generation, in which the product water and steam undergo hightemperature cleavage to Hz and Oz. Coal is burned as a consumable negative electrode. Production of steam and power occurs with simultaneous production of 02, for return to the combustion zone, and Hz, which can enter an energy distribution grid as either synthesis gas or can be stored as a fuel for use in power generation during peak demand periods. The CO2 produced from combustion is separated from water and steam mixtures and can then be removed and stored (to prevent atmospheric emissions).

03101375 Study of detached plume in coke oven Pyrolysis as a technique for separating heavy metals from hyperaooumuiators. Part I: Preparation of synthetic hypemccumulator biomass

03101372

Koppolu,

K. and Clements,

L. D Biomass and Bioenergy.

2003, 24, (l),

69-79.

Phytoremediation involves removing metals from soil or water for environmental reasons and phytomining implies extraction of metals from soils rich in metal content, using hyperaccumulators for economic gain. ‘Synthetic hyperaccumulator biomass’ (SHB) was prepared to mimic the metal concentration and/or chemistry found in actual hyperaccumulators. The purpose for developing a technique to produce SHB was to prepare sufficient quantities of samples for use in lab-scale and pilot-scale pyrolysis experiments. Bench scale experiments were conducted at 27°C to incorporate metals like Ni, Zn, Cu, Co, and Cr into 3 g of SHB (milled corn stover) using metal acetate and metal citrate salt solutions. Two parameters, namely concentration of metal salt and soaking time were studied. Suitable acetate and/or citrate feed concentrations and soaking times were then selected for preparing the SHB, containing a particular heavy metal, for lab-scale and pilot-scale pyrolysis experiments. For the lab-scale pyrolysis experiments, 160 g of the SHB was prepared using the five heavy metal acetate and citrate feeds. About 500 g of the SHB was prepared for the pilot-scale experiments using the Ni, Zn, and Cu acetate feeds. Except for lab-scale/Cu acetate feed (6% higher), lab-scale/Cr acetate feed (20% higher), lab-scale/Ni citrate feed (8% lower), and pilot-scale/Cu acetate feed which was 2.2 times higher than the literature value, concentration of metal in the other nine types of SHB prepared for the lab-scale and pilot-scale pyrolysis experiments was within the hyperaccumulator metal concentration ranges found in the literature. The final goal of this work, which is presented in a series of four parts, is to demonstrate the use of pyrolysis as a first step towards the recovery of heavy metals from hyperaccumulators used for phytoremediation 03/01373

or phytomining.

Research of municipal solid waste pyrolysis gas

Chu, H. and Li, A.-.M. Anyuan Yu Huaqjing Xuebao, 2002, 2, (2). 2227. (In Chinese) Municipal Solid Waste has becoming a more and more serious concern for all the cities nowadays both at home and abroad. Based on the investigation into the related departments in Shenyang municipality, this paper has made a detailed account of the following problems. Firstly, an analysis was made of the basic chemical composition of the

Huang, T.-X and Liu, Y.-.C. Kuangye lTa+i, Taiwan), 2002, 46, (l), 123-130. (In Chinese) The detached white plume in coke oven has been existing for a long time. The object of this study is to find the causes of plume formation through the observation of plume opacity and the component analysis of flue dust. Finally by the modification of operation mode it is hoped that the opacity of plume can be decreased. After overall analysis of in-stack opacity, out-stack opacity and operation condition, it is found that the plume has been existing in the stack, so the in-stack and outstack opacities are changing in the same direction and the concentration of flue dust is linearly related with in-stack opacity. The major component of flue dust is NH4HSOd. It is deduced that SO* is catalysed to SO3 and finally converted into NHdHSOd when the flue is flowing through the hot regenerative chamber built with refractory block which contains catalyst-oxidized metal. Now the coke oven is operated with 20 min reversal cycle. If the reversal cycle is shortened to 10 min, the temperature of refractory block is not so high to raise the SO3 conversion rate so the opacity of plume can be decreased within the 20% EPA regulation value.

03/01376

The CO2 gasification klnetlcs of olive residue

P. rt al. Biomass and Bioenergy, 2003, 24, (2), 151-161. Orujillo, sometimes called wood matter from pressed oil-stone (WPOS) is a residue from the olive oil mill industry. The generation of this biomass residue is concentrated in small areas allowing its use as fuel for medium size gasification and combustion plants. Rates of gasification of WPOS char were measured in a TGA at various temperatures (80&85&875-900_95O”C), CO2 partial pressures (0.2& 0.35-0.50 bar) and CO partial pressures (O.&O.20 bar). The experiments were carried out with a monolayer bed of very fine particles well exposed to the gas so as to minimize mass and heat transfer resistances. Two kinetic models, the nth order model and Langmuir-Hinshelwood model, have been used to lit with the reactivity data. For pure CO2 experiments the kinetic parameters of nth order model were E= 133 kJ/ mol and n=0.43. The Langmuir-Hinshelwood kinetic model clearly describes the observed CO inhibition effect on the CO2 gasification.

Ollero,

03/01377 The potential for adding plastic waste fuel at a coal gasification power plant Campbell,

P. E. et al. Waste Management

& Research,

2002,

19, (6),

526m~532.

Fuel and Energy Abstracts

July

2003

245