Lack of synergetic effects in the pyrolytic characteristics of woody biomass/coal blends under low and high heating rate regimes

Pyrolytic behaviours of woody biomass/coal mixtures were investigated under both low and high heating rate conditions over a range of temperatures between 200°C and 1400°C. Results obtained from this comprehensive investigation indicated that the pyrolytic characteristics of the mixtures follow those of the parent materials in an additive manner. Therefore, under inert (non-oxidising) conditions the two fuels undergo independent thermal conversion without any chemical interactions. As such, the yield of the major pyrolysis products (e.g. volatiles and char) is proportional to the percentage of woody biomass and coal in the mixture. This confirms the hypothesis made by a number of researchers about the lack of synergistic effects in the yield of pyrolysis products from blended coal and woody biomass. However, in this study, we show that even the compositions of the gaseous products from blended samples are linearly proportional to those of their parent fuels (lack of synergistic effects). These findings can potentially help to understand and predict the behaviour of woody biomass/coal blends in practical combustion systems

Pyrolytic characteristics of blended coal and woody biomass

Pyrolytic characteristics of biomass/coal mixtures were investigated under conditions pertinent to pulverised fuel boilers. It was found that the mixtures of biomass/coal follow the behaviour of their parent materials in an additive manner. The two fuels did not chemically interact under inert conditions indicating a general lack of synergistic effects. As such, the yield of the major pyrolysis products is linearly proportional to the percentage of biomass and coal in the mixture. Even the compositions of the gaseous products from blended samples are linearly proportional to those of their parent fuels. These findings can potentially help to understand and predict the behaviour of biomass/coal blends in practical systems

Online Study Satisfaction of Accounting Students in Thailand during COVID-19 Pandemic

This research aimed to examine online study satisfaction of college students in Ubon Rathchathani province, Thailand and to compare their satisfaction in online study during COVID-19 pandemic according to personal factors. The population in this research was college students accounting major from Ubon Ratchathani province, the sample group was 380 people selected by cluster sampling method. Research instrument was questionnaire with 5 level of rating scale, CVI at .86. The statistics used in research were percentage, mean, standard deviation, t-test, and f-test. The research showed that college students had high level of satisfaction on study online during COVID-19 pandemic thus consider from every aspects that contain high level of satisfaction. The average scores descending were educational aspect, utilization aspect, and technology aspect

Pyrolysis and combustion characteristics of an indonesian low-rank coal under O₂/N₂and O₂/CO₂ conditions

Pyrolysis and combustion characteristics of an Indonesian low-rank coal are studied under oxy-fuel (O₂/CO₂) and air (O₂/N₂) conditions using a drop tube furnace (DTF) and a thermogravimetric analyzer (TGA). Raw coal, dried coal, and binderless briquette samples of the same coal were used in the experiments, and the effects of drying and binderless briquetting on the reactivity of the coal under different conditions were investigated. Chars were prepared in the DTF in both N₂ and CO₂ atmospheres in the temperature range of 800−1400 °C. The reactivity of chars under oxy-fuel and air conditions was analyzed in the TGA. The coal reactivity under oxy-fuel conditions differed from that under air combustion conditions. The temperature at which significant gasification of the coal and char took place in the concentrated CO₂ gas stream was also identified. Characteristics of chars from different conditions were compared. Drying and briquetting had some noticeable influences on the reactivity of the coal under oxy-fuel conditions