Study on deposition tendency of coal ash under various gasification environments through DTF

The co-combustion of fossil fuels with CO2-neutral fuels is an attractive way both to decrease CO2 emissions in energy production and to use fuel synergies which decrease each other’s undesirable properties. This paper presents a new approach to understand and predict the chlorine deposition tendency in the co-combustion of coal with biomass and RDF. This novel approach combines the results from deposit analysis with flue gas emission measurement and advanced fuel characterization methods. The experiments were carried out in a 0.1 MW circulating fluidized bed reactor. Two different types of bituminous coal (South African and Polish) were co-fired with RDF, demolition wood and bark. The traditional way to predict risk for chlorine deposition, the fuel S/Cl molar ratio, and the safe limit molar ratio > 4 for biofuels were shown to be inadequate. The mineral kaolinite in coal ash was found to be able to capture alkalis and, in most cases, more effectively than sulphur compounds. The alkali capture capability of coal sulphur is quickly consumed due to reactions with calcium compounds. Furthermore, the ability of SO2 to sulfate alkali chlorides were found to be weaker than presented in the literature. Thus in many cases it is only kaolinite that keeps Cl away from the deposit. New index to predict chlorine deposition tendency were introduced: the reactive (Al+Si)/fuel Cl molar ratio. The results showed a good correlation between the chlorine concentration in the deposit and the new index. The reactive (Al+Si)/fuel Cl molar ratio higher than 8–10 was found to prevent chlorine to deposit. The new approach for better understanding and preventing of chlorine deposition promotes the co-combustion of coal with biomass and RDF by introducing new synergy benefits.

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Solid mineral fuels. Major and minor elements in hard coal ash and coke ash. Wavelength dispersive X-ray fluorescence spectrometric method

10.3403/30232590 ◽

2012 ◽

Keyword(s):

Coal Ash ◽

Hard Coal ◽

Spectrometric Method ◽

X Ray ◽

Minor Elements

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Pengaruh Penggunaan Batu Basalt Lampung dan Batubara dalam Bahan Baku terhadap Karakteristik Klinker

Jurnal Teknologi Bahan dan Barang Teknik ◽

10.37209/jtbbt.v10i1.167 ◽

2020 ◽

Vol 10 (1) ◽

pp. 49

Author(s):

Suharto Suharto ◽

Muhammad Amin ◽

Muhammad Al Muttaqii ◽

Syafriadi Syafriadi ◽

Kiki Nurwanti

Keyword(s):

Experimental Study ◽

Raw Materials ◽

Coal Ash ◽

Heating Time ◽

Raw Material ◽

Silica Sand ◽

Cement Clinker ◽

Duration Of Heating

Experimental study on the use of basalt stone originated from Lampung has been conducted to evaluate its potential for a partial substitute of raw material in production of cement clinker. The basalt stone contains minerals of anorthite, augite, and albite phases that are required for clinker formation. In this study, the main raw materials were 80% limestone, 10% silica sand, 9% clay and 1% iron sand. The raw material in these experiments were mixtures 90% or 80% of the main raw material and 10% or 20% of basalt stone. The effect of adding coal to raw materials was also studied to see the possibility of an increase in clinkerization temperature inside the raw material mixture, and at the same time to see the effect of coal ash on clinker composition. Clinker obtained from heating of raw materials at a temperature of 1100oC had LSF of 94.1% and 95.1% (heating time of 1 and 3 hours). If heating is carried out at 1200oC, the clinker had LSF of 97.7% and 98.0% (heating time of 2 and 3 hours, respectively). Depending on the temperature and duration of heating, the clinker mostly had SM in the range of 2.18-2.40% , and AM in the range of 0,78-1.80%. Characterization using XRD showed that the clinker consisted of larnite and gehlenite phases, and dominated by CaO.Batu basalt Lampung telah diuji potensinya sebagai pengganti sebagian bahan baku utama pembuatan klinker semen. Batu basalt tersebut memiliki mineral-mineral dalam fase anorthite, augite, dan albite yang diperlukan pada pembentukan klinker. Pada penelitian ini, bahan baku utama adalah batu kapur 80%, pasir silika 10%, tanah liat 9% dan pasir besi 1%. Campuran bahan baku klinker adalah 90% atau 80% bahan baku utama dan 10% atau 20% batu basalt. Efek penambahan batubara ke dalam bahan baku klinker juga dipelajari untuk melihat kemungkinan kenaikan temperatur klinkerisasi di dalam campuran bahan baku, dan sekaligus untuk melihat efek abu batubara terhadap komposisi klinker. Klinker hasil pemanasan bahan baku pada temperatur 1100oC memiliki LSF 94,1% dan 95,1% (lama pemanasan 1 dan 3 jam). Jika pemanasan dilakukan pada 1200oC, klinker memilik LSF 97,7% dan 98,00% (lama pemanasan 2 dan 3 jam). Tergantung pada temperatur dan lama pemanasan, klinker hasil percobaan ini umumnya memiliki SM 2,18-2,40%, dan AM antara 0,78-1,80%. Karakterisasi dengan XRD menunjukkan bahwa klinker terdiri dari fase larnite dan gehlenite, dan didominasi CaO.

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Sustainable Concrete Application in the Manufacture of University Urban Furniture

MATEC Web of Conferences ◽

10.1051/matecconf/201930305001 ◽

2019 ◽

Vol 303 ◽

pp. 05001

Author(s):

Mónica Bedoya ◽

Federico Rivera ◽

María Rico ◽

David Vélez ◽

Andrés Urrego ◽

...

Keyword(s):

Finite Elements ◽

Mechanical Characteristics ◽

Coal Ash ◽

Sustainable Concrete ◽

Waste Production ◽

Construction And Demolition Wastes ◽

The World ◽

Sustainable Materials ◽

The University ◽

Community Diagnosis

It is clear that construction and demolition wastes (CDW) are constantly increasing throughout the world and these wastes can be used effectively to minimize the consumption of natural resources in the manufacture of more sustainable concrete. The CDW occupy an important segment of world waste production and its generation reached approximately 3 billion tons in 2012 in 40 countries [1]. Although this topic has been studied in the world, it is still valid for the reuse of waste that is constantly increasing, and although in many countries there are already examples of its use this type of concrete in Colombia and in the Medellìn city lacks applications. This project proposes the application of a sustainable concrete made with CDW and coal ash in the Medellín city for its implementation in the construction of urban furniture. A university community diagnosis of the needs in terms of furnishing was made. With the design reached, a modular chair was proposed to enable spaces within the university. The mechanical characteristics of the concrete and the design of the chair are evaluated and a simulation is done through finite elements to evaluate the viability of the proposed concrete, finding that with these properties is possible to manufacture durable and sustainable furniture that serves as an example for the application of sustainable materials

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