Investigation of ash deposition dynamic process in an industrial biomass CFB boiler burning high alkali and chlorine fuel

The circulating fluidized bed (CFB) boiler is a mainstream technology of biomass combustion generation in China. The high flue gas flow rate and relatively low combustion temperature of CFB make the deposition process different from that of a grate furnace. The dynamic deposition process of biomass ash needs further research, especially in industrial CFB boilers. In this study, a temperature-controlled ash deposit probe was used to sample the deposits in a 12 MW CFB boiler. Through the analysis of multiple deposit samples with different deposition times, the changes in micromorphology and chemical composition of the deposits in each deposition stage can be observed more distinctively. The initial deposits mainly consist of particles smaller than 2 μm, caused by thermophoretic deposition. The second stage is the condensation of alkali metal. Different from the condensation of KCl reported by most previous literatures, KOH is found in deposits in place of KCl. Then, it reacts with SO2, O2 and H2O to form K2SO4. In the third stage, the higher outer layer temperature of deposits reduces the condensation rate of KOH significantly. Meanwhile, the rougher surface of deposits allowed more calcium salts in fly ash to deposit through inertial impact. Thus, the elemental composition of deposits surface shows an overall trend of K decreasing and Ca increasing.

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Ash deposition mechanism of shoe manufacturing waste combustion in a full-scale CFB boiler

Fuel Processing Technology ◽

10.1016/j.fuproc.2021.106948 ◽

2021 ◽

Vol 221 ◽

pp. 106948

Author(s):

Yueming Wang ◽

Xinglei Qiu ◽

Zhengang Zhou ◽

Yuanqiang Duan ◽

Lin Li ◽

...

Keyword(s):

Full Scale ◽

Ash Deposition ◽

Deposition Mechanism ◽

Cfb Boiler ◽

Waste Combustion ◽

Shoe Manufacturing ◽

Shoe Manufacturing Waste

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Management of affected areas by the pollution of the slag and ash deposits of CET Mintia

MATEC Web of Conferences ◽

10.1051/matecconf/202134203014 ◽

2021 ◽

Vol 342 ◽

pp. 03014

Author(s):

Andreea Cristina Tataru ◽

Aurora Stanci ◽

Dorin Tataru

Keyword(s):

Environmental Management ◽

Air Pollution ◽

Environmental Protection ◽

Thermoelectric Power ◽

Power Plants ◽

Deposition Process ◽

Environmental Problems ◽

Environmental Management System ◽

Ash Deposition ◽

Thermoelectric Power Plants

The technological processes from the combustion of certain materials in boilers results in significant amounts of slag and ash waste. Such industries that produce waste as slag and ash as a result of the process obtain electricity in the thermoelectric power plants. The biggest environmental problems caused by the thermoelectric power plants are air pollution and landscaping. In order to reduce the pollution caused by the slag and ash deposits, they should be ecologized upon completion of the slag and ash deposition process. An environmental management system aims at finding the most effective solutions for complying with environmental protection requirements. In this case, more economic solutions are needed to comply with the legislation. In this paper we will present a method of greening the slag and ash deposits of the thermoelectric power plants Mintia and the related costs.

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Effects of temperature and additives on ash transformation and melting of high-alkali-chlorine coal

Thermal Science ◽

10.2298/tsci200313271z ◽

2020 ◽

Vol 24 (6 Part A) ◽

pp. 3501-3510

Author(s):

Jingbin Zi ◽

Daoyang Ma ◽

Zia Rahman ◽

Xuebin Wang ◽

Hao Li ◽

...

Keyword(s):

Coal Ash ◽

Ash Deposition ◽

High Sodium ◽

Melting Characteristics ◽

Ash Melting ◽

Calcium Magnesium ◽

Effects Of Temperature ◽

High Alkali ◽

Main Component ◽

High Aluminum

The high contents of sodium and chlorine in Shaerhu coal aggravate severe slag-ging ash deposition and corrosion in boilers. Adding proper additives is an effec-tive way to reduce slagging ash deposition and corrosion. Based on the experi-mental study, this paper investigated the effect of combustion temperature, types of additives, and its amount on the ash transformation and melting of high sodium chloride Shaerhu coal. The ash melting characteristics, elemental compositions and mineral compositions of the ash produced under different conditions were characterized. Results showed that the contents of calcium, magnesium, and sul-phur in the coal ash varied slightly with the temperature increasing. Chlorine and sodium released rapidly from coal at 550-815?C and 550-700?C, respectively. At 1050?C, calcium silicate was observed as the main component of the ash. The addition of different additives had no significant effect on chlorine and sodium capture. The addition of silicon species lowered the ash fusion temperatures, while the aluminum had an opposite effect. To prevent the furnace from slagging, a high aluminum additive is proposed to be adopted.

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Research on element migration and ash deposition characteristics of high-alkali coal in horizontal liquid slagging cyclone furnace

Fuel ◽

10.1016/j.fuel.2021.121962 ◽

2022 ◽

Vol 308 ◽

pp. 121962

Author(s):

Shihao Hu ◽

Yuguo Ni ◽

Qi Yin ◽

Jiankang Wang ◽

Laiquan Lv ◽

...

Keyword(s):

Ash Deposition ◽

High Alkali ◽

Element Migration ◽

Cyclone Furnace

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Ash Deposition and Slagging Behavior of Xinjiang High-Alkali Coal in a 20MWth Cyclone Combustion Test Facility

10.1007/978-981-16-1657-0_14 ◽

2021 ◽

pp. 179-188

Author(s):

Xiaojiang Wu ◽

Yigong Zhou ◽

Yezhu Sun ◽

Zhongxiao Zhang ◽

Mingqiang Li ◽

...

Keyword(s):

Test Facility ◽

Ash Deposition ◽

High Alkali

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Ash deposition and slagging behavior of Chinese Xinjiang high-alkali coal in 3 MWth pilot-scale combustion test

Fuel ◽

10.1016/j.fuel.2016.03.069 ◽

2016 ◽

Vol 181 ◽

pp. 1191-1202 ◽

Cited By ~ 54

Author(s):

Xiaojiang Wu ◽

Xiang Zhang ◽

Kai Yan ◽

Nan Chen ◽

Jianwen Zhang ◽

...

Keyword(s):

Pilot Scale ◽

Ash Deposition ◽

High Alkali

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Ash deposition behavior of a high-alkali coal in circulating fluidized bed combustion at different bed temperatures and the effect of kaolin

RSC Advances ◽

10.1039/c8ra05997g ◽

2018 ◽

Vol 8 (59) ◽

pp. 33817-33827 ◽

Cited By ~ 11

Author(s):

Yanquan Liu ◽

Leming Cheng ◽

Jieqiang Ji ◽

Qinhui Wang ◽

Mengxiang Fang

Keyword(s):

Fluidized Bed ◽

Combustion Temperature ◽

Circulating Fluidized Bed ◽

Ash Deposition ◽

Fluidized Bed Combustion ◽

Deposition Behavior ◽

Zhundong Coal ◽

High Alkali ◽

Circulating Fluidized Bed Combustion

This work reports the influence of combustion temperature on the ash deposition of Zhundong coal in a CFB, and evaluates the effect of kaolin.

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MORFOMETRI GISIK KAWASAN PANTAI WISATA BAHARI SARIO KOTA MANADO

JURNAL PESISIR DAN LAUT TROPIS ◽

10.35800/jplt.9.2.2021.34851 ◽

2021 ◽

Vol 9 (2) ◽

pp. 35

Author(s):

Zulkifli Otoluwa ◽

Rignolda Djamaluddin ◽

Royke M Rampengan ◽

Jane Mamuaya ◽

Esry T Opa ◽

...

Keyword(s):

Dynamic Process ◽

Coastal Area ◽

Deposition Process ◽

Southwestern Part ◽

Beach Morphology

Beach formation has an important role in protecting land from the action of the sea and it is useful for recreation, conservation and other uses. In “Wisata Bahari Sario” Kota Manado coastal area there is still a particular area of beach that is used for various purposes, so it is important to study its morphology. This research was conducted with the aim of describing morphology and analyzing oceanographic factors that affected the dynamic process of beach morphology. The results showed that the beach had an area of 422.69 m2, with the criteria for short slopes in the Northeast and long slopes in the Southwest. The shapes of the beach surface were in the form of gutters and shoots, their appearance was more visible towards the Southwest. In general, the deposition process took place more intensively in the Southwestern part of the beach. Keywords: Beach, Morphology, Slope, Deposition

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