carbon deposition
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GR Millward ◽  
D Cox ◽  
M Aindow ◽  
PJ Darley ◽  
HE Evans ◽  

2022 ◽  
Vol 2160 (1) ◽  
pp. 012008
He Huang ◽  
Kai Yang ◽  
Xiaomei Yang

Abstract When checking and cleaning whether there is carbon deposit in the cylinder of gasoline engine, it is often time-consuming and laborious, and the process is complicated. Once the disassembly and assembly is not in place, its service life will be affected. When cleaning with carburizing agent and cleaning agent, it is difficult to fully contact with the cylinder wall, so the cleaning effect is poor and it is easy to leave its chemical composition in the engine. In this paper, some common ways of engine cylinder cleaning are studied, and a device for detecting and cleaning carbon deposition in gasoline engine cylinder is designed. The purpose is to provide a new convenient, simple and practical method for detecting and cleaning carbon deposition in automobile engine cylinder in the current market.

В.А. Усольцев ◽  
В.Ф. Ковязин ◽  
И.С. Цепордей

В связи с глобальным потеплением климата оценка углеродного цикла в лесных экосистемах приобрела особое значение. Один из методов определения депонированного в лесах углерода основан на использовании конверсионных коэффициентов биомассы (ККБ) и данных Государственного учета лесного фонда (ГУЛФ). Путем объединения моделей ККБ с данными ГУЛФ в двух экорегионах России – таежном и лесостепном – было установлено, что за 20–25- летний период накопление органического углерода в таежной зоне значительно меньше (5%) по сравнению с лесостепной зоной (39%). Несмотря на существующие риски стихийных бедствий в лесостепном экотоне, за четверть века наблюдается значительный рост депонированного углерода. Это произошло вследствие высокой доли молодняков в начале анализируемого периода, обладающих повышенным приростом по отношению к спелым древостоям. Сопоставимые результаты были получены одним и тем же методом в разных экорегионах планеты: от 8% за 5 лет в Китае до 68% за 50 лет в Японии. Сравнение результатов, полученных предложенным методом и методом IIASA (Австрия), показало минимальное расхождение (3%), что дает основание считать полученные оценки депонирования углерода близкими к реальности. Однако сохраняется неопределенность, связанная с качеством данных ГУЛФ и депонированием углерода в почве. Due to the global warming of the climate, the assessment of the carbon cycle in forest ecosystems has become particularly important. One method for determining deposited carbon is based on the use of biomass expansion factors (BEF) and State Forest Inventory (SFI) data. By combining BEF models with SFI data in two ecoregions of Russia – taiga and forest-steppe – it was found that over a 20–25-year period, accumulating the carbon deposition in the taiga zone is significantly less (5%) compared to the forest-steppe zone (39%). Despite the existing risks of natural disasters in the forest-steppe ecotone, there is a significant increase in carbon deposition over a quarter of a century. This was due to the high proportion of young stands at the beginning of the analyzed period, which have increased growth in relation to old stands. Comparable results were obtained by the same method in different ecoregions of the planet (from 8% in 5 years in China to 68% in 50 years in Japan). A comparison of the results obtained by the proposed method and the IIASA (Austria) method showed a minimal discrepancy (3%), which gives reason to consider the above estimates of carbon deposition close to reality. However, uncertainties remain related to the quality of the SFI data and the carbon deposition in the soil.

Galina I. Martsinkevich ◽  
Iryna I. Shchasnaya ◽  
Aliaksandr A. Karpichenka ◽  
Dzmitry S. Varabyou

The problems of the formation of hazardous natural and man-made processes in industrial cities, contributing to the emergence of environmental risks, are presented. To date, an extensive literary material has been accumulated on this problem, concerning the causes of its occurrence, analysis of the patterns of development, and the possibilities of managing risks, including the environmental ones. It has been established that the list of reasons for the formation of risks in cities lacks one of the most important factors that we have discovered – the structure of urban landscapes, which are quite large objects of urban development. To identify the role of these objects in the formation of environmental risks, the cities of Orsha and Pinsk were selected. These cities were laid down almost simultaneously at the beginning of the 11th century, but they have a different history of development. Maps of urban landscapes of cities were compiled, geochemical studies of their soil cover were carried out, geochemical and thermal anomalies of the surface were revealed, the volumes of ecosystem services (carbon absorption) by green spaces were calculated. It was found that urban landscapes perform various functions in the system of environmental risks: some of them contribute to the development of hazardous processes, others – to mitigate them. So, soil pollution with heavy metals (with an excess of the content of Pb, Cr and Cu over the MPC by 1.2–5.6 times in Pinsk), the strongest heating of the surface (8–16 °C higher than the air temperature in Pinsk and Orsha) and low carbon deposition (100–500 t per year) are typical for urban landscapes of the historical center, urban landscapes with a predominance of industrial buildings, urban landscapes for complex residential multi-storey, public and industrial buildings. Urban landscapes, in the structure of which there are elements of landscape and recreational areas of public use (parks, forest parks, squares), as well as agricultural lands and water bodies, are characterised by a low content of heavy metals in soils (below the MPC in Pinsk, below the background in Orsha), low surface temperature (2–3 °C higher than the air temperature), high volume of carbon deposition (2.6–2.8 thsd t per year). An assessment of the probability of risks associated with the described processes was carried out, which helped to find out that they correspond to the categories of «acceptable» and «neglected», options for risk management were proposed.

2021 ◽  
Vol 13 (24) ◽  
pp. 13855
Naushad Ahmad ◽  
Rizwan Wahab ◽  
Salim Manoharadas ◽  
Basel F. Alrayes ◽  
Fahad Alharthi

For the commercialization of syngas production, the utilization of greenhouse gases and the fabrication of an active catalyst for the dry reforming methane (DRM) process are the biggest challenges because of deactivation by carbon deposition, oxidation, sintering, and loss of active surface sites under high temperature. In the present article, BaNiO3 perovskite was synthesized by the coprecipitation method, and its reduced form (r-BNO) was utilized for syngas production by the DRM reaction. It was found that the r-BNO showed high stability and good resistance against carbon deposition, however, the conversions (CH4 and CO2) have been found to be less than 50%. Many techniques such as TGA, XRD, FT-IR, UV-Vis, BET, SEM, TEM, XPS, TPR, TPO, and TPD were used in order to investigate the physical properties and evaluation conditions for syngas production. From the obtained results, it was revealed that BaNiO3 perovskite possessed a hexagonal crystal structure and perforated–rough surface; in addition, its structure was virtually regenerated by oxidation of the r-BNO catalyst, which provides a convenient way to regenerate the original catalyst in an oxidative atmosphere. Structural and surface alterations of the used catalyst, after the DRM reaction, were characterized by using TGA, TPO, and TEM, and it was found that there was no significant deposition of inert carbons (D and G) and deactivation of the r-BNO catalyst.

Catalysts ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1468
Ho-Ryong Park ◽  
Beom-Jun Kim ◽  
Yeol-Lim Lee ◽  
Seon-Yong Ahn ◽  
Kyoung-Jin Kim ◽  

Research is being actively conducted to improve the carbon deposition and sintering resistance of Ni-based catalysts. Among them, the Al2O3-supported Ni catalyst has been broadly studied for the dry reforming reaction due to its high CH4 activity at the beginning of the reaction. However, there is a problem of deactivation due to carbon deposition of Ni/Al2O3 catalyst and sintering of Ni, which is a catalytically active material. Supplementing MgO in Ni/Al2O3 catalyst can result in an improved MgAl2O4 spinel structure and basicity, which can be helpful for the activation of methane and carbon dioxide molecules. In order to confirm the optimal supports’ ratio in Ni/MgO-Al2O3 catalysts, the catalysts were prepared by supporting Ni after controlling the MgO:Al2O3 ratio stepwise, and the prepared catalysts were used for CO2 reforming of CH4 (CDR) using coke oven gas (COG). The catalytic reaction was conducted at 800 °C and at a high gas hourly space velocity (GHSV = 1,500,000 h−1) to screen the catalytic performance. The Ni/MgO-Al2O3 (MgO:Al2O3 = 3:7) catalyst showed the best catalytic performance between prepared catalysts. From this study, the ratio of MgO:Al2O3 was confirmed to affect not only the basicity of the catalyst but also the dispersion of the catalyst and the reducing property of the catalyst surface.

Hafnee Lateh ◽  
Juntakan Taweekun ◽  
Kittinan Maliwan ◽  
Zainal Alimuddin Zainal Alauddin ◽  
Sukritthira Rattanawilai

Tar derived from biomass gasification system needs to be eliminated before applying biomass producer gas for avoiding equipment and its gas problems. In this study, thermal and catalytic cracking methods of biomass tar along with microwave assistance in heat transfer were experimented at various temperatures during 650-1,200 °C and residence at 0.24-0.5 s. The results present that high tar removal efficiency by approximately 90 % under thermal cracking treatment and about 98 % with catalytic cracking method. It also shows that the catalytic cracking especially modified catalyst could be lowered carbon deposition on catalyst surface.

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