Evaluation of ash related problems during sewage sludge combustion

A good function of waste-to-energy installation requires knowledge of the combustion characteristics of the fuel and fusion characteristics of the ash produced in the combustion process. Sewage sludge could be considered as renewable fuel due the high quantity of organics of sufficiently high calorific value. The combustion of sewage sludge can cause operating problems due to high ash content containing mineral compounds. This paper presents the oxide composition of three kinds of sewage sludge ashes and the influence on the slagging and fouling process in combustion. For comparation, two coal samples were selected, a low and a high rank coal. The mineral matter were investigated by the X-ray fluorescence analytical technique using the Rigaku CG X-ray Spectrofluorimeter. The evaluation of slagging and fouling process was performed on the basis of some indices: the basic oxides, the base-to-acid ratio, the slagging index and the fouling index. The conclusion based on experimental studies is that depending on mineral content the sewage sludge ash can cause high to moderate slagging and fouling hazard.

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Nanocrystalline and stacking-disordered β-cristobalite AlPO4: the now deciphered main constituent of a municipal sewage sludge ash from a full-scale incineration facility

Powder Diffraction ◽

10.1017/s0885715614001213 ◽

2015 ◽

Vol 30 (S1) ◽

pp. S31-S35 ◽

Cited By ~ 4

Author(s):

B. Peplinski ◽

C. Adam ◽

B. Adamczyk ◽

R. Müller ◽

M. Michaelis ◽

...

Keyword(s):

Sewage Sludge ◽

Fluidized Bed ◽

Large Scale ◽

Sodium Hydroxide Solution ◽

Direct Proof ◽

Municipal Sewage ◽

Municipal Sewage Sludge ◽

Sewage Sludge Ash ◽

X Ray ◽

Sludge Ash

For the first time evidence is provided that a nanocrystalline and stacking-disordered, chemically stabilized β-cristobalite form of AlPO4 occurs in a sewage sludge ash (SSA). This proof is based on a combined X-ray powder diffraction and X-ray fluorescence investigation of an SSA produced at a large-scale fluidized bed incineration facility serving a catching area with a population of 2 million. The structural and chemical characterization was carried out on ‘as received’ SSA samples as well as on solid residues remaining after leaching this SSA in sodium hydroxide solution. Thus, it was ascertained that the observed nanocrystalline and stacking-disordered cristobalite-like component belongs to the aluminum phosphate component of this SSA, rather than to its silicon dioxide component. In addition, a direct proof is presented that the chemically stabilized β-cristobalite form of AlPO4 does crystallize from X-ray amorphous precursors under conditions that mimic the huge heating rate and short retention time (just seconds at T ≈ 850°C), typical for fluidized bed incinerators.

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Quantitative determination of mineral matter in lignite by X-RAY spectrometry, using the Compton effect.

Bulletin of the Geological Society of Greece ◽

10.12681/bgsg.11008 ◽

2016 ◽

Vol 47 (4) ◽

pp. 1645

Author(s):

V. Perdikatsis

Keyword(s):

Organic Matter ◽

Absorption Coefficient ◽

Quantitative Determination ◽

Calorific Value ◽

Matter Content ◽

Compton Effect ◽

Mineral Matter ◽

X Ray ◽

Mineral Phases

For the evaluation of lignite quality, apart from the calorific value, it is necessary to determine the mineral phases, which are deposited simultaneously with the organic matter during the formation of peat or formed epigenetically during the coalification stages. The mineral matter content is usually expressed as ash, after the combustion of lignite, and its determination is a quite time consuming process. In this paper an attempt is made for a fast and easy quantitative determination of mineral matter in lignite samples with unknown concentrations, with the use of an X-ray spectrometer and in particular the Compton effect of the X-ray tube. The intensity of the Compton peak is a function of the mass absorption coefficient of the lignite sample, which in turn depends on the type and amount of the mineral matter contained. Using this property of the Compton Effect, the percentage of mineral matter of lignite was determined. The method was verified by analyzing lignites with known concentrations of inorganic mater. The results of this study showed, that the mineral matter content can be determined, by the proposed method, fast and accurately without lignite combustion.

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Hydrothermal carbonization of sewage sludge: Multi-response optimization of hydrochar production and CO2-assisted gasification performance

10.21203/rs.3.rs-954940/v1 ◽

2021 ◽

Author(s):

Shuai Guo ◽

DanDan Xu ◽

Xin Guo ◽

Xingcan Li ◽

Chenchen Zhao

Keyword(s):

Acetic Acid ◽

Sewage Sludge ◽

Activity Index ◽

Calorific Value ◽

Hydrothermal Carbonization ◽

Carbonization Temperature ◽

Waste To Energy ◽

Response Optimization ◽

C 30 ◽

Processing Techniques

Abstract The harmful effects of improper sewage sludge (SS) treatment on the environment inspire the search for more benign sludge processing techniques such as hydrothermal carbonization (HTC); the abundant organic matter in SS is used for energy recovery. Herein, response surface methodology (RSM) was used to optimize the HTC-based preparation of SS hydrochar and its gasification performance. Specifically, the hydrochar yield, higher heating value (HHV), and gasification activity index were selected as optimization goals, while carbonization temperature (160–260°C), residence time (30–150 min), and acetic acid concentration (0–1.5 M) were selected as factors influencing the HTC process and CO2-assisted gasification performance. Carbonization temperature was the dominant parameter determining hydrochar yield, HHV, and gasification activity. The hydrochar yield (82.69%) and calorific value (7820.99 kJ kg−1) were maximized under comparatively mild conditions (160°C, 30 min, and 0.07 M acetic acid), whereas the gasification activity index (0.288 s−1) was maximized under harsher conditions (211.34°C, 88.16 min, and 1.58 M acetic acid). The obtained results help to guide the HTC of SS intended for gasification, thus promoting the development of this promising waste-to-energy technology, and may facilitate the design and further optimization of thermochemical SS conversion.

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Research of Lime-Mediated Sewage Sludge Use as Metallurgy Sintering Ingredients in the Sinter Industry

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.581-582.888 ◽

2012 ◽

Vol 581-582 ◽

pp. 888-894

Author(s):

Yi Xing ◽

Fan Zhao ◽

Chen Hong ◽

Guang Wei Yu ◽

Cheng Sheng Yue ◽

...

Keyword(s):

Sewage Sludge ◽

Burning Rate ◽

Positive Impact ◽

Calorific Value ◽

Sintering Process ◽

X Ray Diffraction ◽

X Ray ◽

Utilization Coefficient ◽

Existing Form ◽

Quality Indexes

This paper discusses the feasibility of the lime-mediated sewage sludge replace the fuels and flux as metallurgy ingredients, the influence of lime-mediated sewage sludge used in metallurgy sintering process to the sinter performance. The calorific value of the sludge was 4.67MJ/kg. The X-ray diffraction (XRD) showed that the main existing form of Calcium in the lime-mediated sewage sludge is CaCO3 at 550°C, and almost is CaO at 1100°C. This provided the basis to the sludge used as sintering ingredients. Sintering cup experiment results showed that Lime dry sludge have a positive impact on sintering, the sinter quality indexes are improved. When sludge ratio is 3.00%, the vertical sintering burning rate is 21.28mm/min, the yield is 72.62%, the utilization coefficient is 1.455T/m2•h, fuel consumption from 65.65kg/T fall to 59.16kg/T, then concluded that the flux and fuel ratio replaced by lime-mediated sewage sludge were 43.3%, 13.3% respectively.

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Leaching behavior of phosphorous compounds from sewage sludge ash based on quantitative X-ray diffraction analysis

Waste Disposal & Sustainable Energy ◽

10.1007/s42768-020-00037-w ◽

2020 ◽

Vol 2 (2) ◽

pp. 113-125

Author(s):

Pinjing He ◽

Xiaotong Zhang ◽

Fan Lü ◽

Liming Shao ◽

Hua Zhang

Keyword(s):

Sewage Sludge ◽

Diffraction Analysis ◽

X Ray Diffraction ◽

Leaching Behavior ◽

Sewage Sludge Ash ◽

X Ray ◽

Sludge Ash ◽

Phosphorous Compounds

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Municipal solid waste (MSW) - competitive raw materials for combustible materials obtaining

Romanian Journal of Ecology & Environmental Chemistry ◽

10.21698/rjeec.2020.221 ◽

2020 ◽

Vol 2 (2) ◽

pp. 170-179

Author(s):

Agnes Serbanescu ◽

◽

Mona Barbu ◽

Ionut Cristea ◽

Lidia Kim ◽

...

Keyword(s):

Municipal Solid Waste ◽

Solid Waste ◽

Raw Materials ◽

Raw Material ◽

Waste To Energy ◽

Household Waste ◽

Mineral Matter ◽

X Ray ◽

Secondary Raw Material ◽

Combustible Materials

Waste-to-energy projects can be classified as a complementary technology for energy recovery from nonrecyclable municipal waste fractions and should therefore not compete with measures to reduce, reuse, and recycle materials. The article presents the characterization of some treated municipal solid wastes as competitive raw materials for combustible materials obtaining. Samples with lignocellulosic and polymeric composition were analyzed, namely 3 samples of SRFs (solid recovered fuels) used as secondary raw material in cement plants, SRF1, SRF2, SRF3; a sample of RDF, consisting of household waste; a sample of fluff (a homogeneous mixture of non-hazardous waste - selected, mechanically treated and dried) used as a secondary raw material in cement plants; 4 samples of municipal solid waste, fractions smaller than 100 mm, after a bio-drying process, with composition: paper and cardboard (70-80%), wood (6-15%), plastic (6-10%), glass and metal (3-14%), MBU1, MBU2, MBU3, MBU4. The waste samples were characterized in terms of technical and elementary characteristics and the ash (obtained by the sample incineration) behavior in the combustion process. The mineral matter was investigated by the X-ray fluorescence analytical technique using the Rigaku CG X-ray Spectrofluorimeter. The analysis of the indices used for the slagging and deposit formation risks evaluation shows that the analyzed samples present an obvious risk of melt formation and deposits, due to a high content of base oxides and silicon oxide.

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Properties of concrete containing microwaved sewage sludge ash

JOURNAL OF MECHANICAL ENGINEERING AND SCIENCES ◽

10.15282/jmes.15.4.2021.01.0667 ◽

2021 ◽

Vol 15 (4) ◽

pp. 8469-8479

Author(s):

M.A. Azed ◽

D.S. Ing

Keyword(s):

Mechanical Properties ◽

Sewage Sludge ◽

Modulus Of Elasticity ◽

Strength Test ◽

Sewage Sludge Ash ◽

X Ray ◽

Sludge Waste ◽

Water Curing ◽

Sludge Ash

Urban population of Malaysia is stated as 72.8% of its total population, and growing every year. Due to this growing number of population, the sewage sludge waste produce every year has also gradually increased. Malaysia itself produces 3.2 million m3 of sewage sludge annually. Normally all of this waste is disposed by landfill. Furthermore, usual production of cement and sewage sludge ash consumes a lot of energy by using incineration process with a very high temperature. Thus, microwave heating method was an alternatives use in this research to reduce the consumption of energy and time used to heat the sewage sludge ash. This research was conducted to investigate the optimum performances of different percentage (0%, 5%, 10%, 15% and 20%) by weight of cement of the Microwaved Sewage Sludge Ash (MSSA) concrete with different curing regime, which was air and water curing. The characteristic of MSSA was tested by X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The mechanical properties of MSSA concrete was examined by Compressive Strength test, Flexural Strength test and Modulus of Elasticity test after 180 days of curing. The MSSA samples were also tested with water absorption test to evaluate the quality of concrete in term of porosity and permeability. Water curing sample with 5% of MSSA (W5) had the best in results compared to other specimens. The mechanical properties of W5 content in concrete shows the most optimum samples due to the densification of pozzolanic reaction and filler effect of MSSA. The curing effect with better result was water curing, as it got highest value of strength in compressive test, flexural test and modulus of elasticity test. As conclusion, based on the results, it is shown the positive impact on using the MSSA as additional material to the cement mixture to improve the quality of the concrete. Thus, this will reduce the disposal of sewage sludge waste on dumping site and improves the quality performances of the concrete.

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Energetic properties of peat saturated with petroleum products

Safety and Reliability of Power Industry ◽

10.24223/1999-5555-2020-13-2-105-109 ◽

2020 ◽

Vol 13 (2) ◽

pp. 105-109

Author(s):

E. S. Dremicheva

Keyword(s):

Crude Oil ◽

Diesel Fuel ◽

Energy Use ◽

Experimental Studies ◽

Calorific Value ◽

Petroleum Products ◽

Ash Content ◽

Motor Oil ◽

Initial Sample

This paper presents a method of sorption using peat for elimination of emergency spills of crude oil and petroleum products and the possibility of energy use of oil-saturated peat. The results of assessment of the sorbent capacity of peat are presented, with waste motor oil and diesel fuel chosen as petroleum products. Natural peat has been found to possess sorption properties in relation to petroleum products. The sorbent capacity of peat can be observed from the first minutes of contact with motor oil and diesel fuel, and significantly depends on their viscosity. For the evaluation of thermal properties of peat saturated with petroleum products, experimental studies have been conducted on determination of moisture and ash content of as-fired fuel. It is shown that adsorbed oil increases the moisture and ash content of peat in comparison with the initial sample. Therefore, when intended for energy use, peat saturated with petroleum products is to be subjected to additional drying. Simulation of net calorific value has been performed based on the calorific values of peat and petroleum products with different ratios of petroleum product content in peat and for a saturated peat sample. The obtained results are compared with those of experiments conducted in a calorimetric bomb and recalculated for net calorific value. A satisfactory discrepancy is obtained, which amounts to about 12%. Options have been considered providing for combustion of saturated peat as fuel (burnt per se and combined with a solid fuel) and processing it to produce liquid, gaseous and solid fuels. Peat can be used to solve environmental problems of elimination of emergency spills of crude oil and petroleum products and as an additional resource in solving the problem of finding affordable energy.

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