Fixed-bed gasification and pyrolysis of organic fraction of MSW blended with coal samples

Buildup of vast quantities of municipal solid waste (MSW) including refuse derived fuel, organic fraction around the urban areas has negative environmental consequences. Gasification and pyrolysis of municipal solid waste could be an attractive option to utilize or convert to a valuable product. This study investigates the thermochemical properties of refuse derived fuel (RDF), organic fraction of MSW (Org MSW) and coal samples. Along with proximate and elemental analysis, calorific values were provided for RDF, MSW organic fraction, and coal samples. This followed by the thermogravimetric analysis of the same samples. In addition, Org MSW MSW and coal samples were blended in a proportion of 0.5/0.5 and 0.25/0.75 and then thermally treated in horizontal tube furnace both under air and inert gases to investigate the pyrolysis and gasification processes. TGA tests revealed that volatile content from Org MSW and RDF begin to be emitted at temperatures above 180-200 °C. Org MSW and RDF lose all their volatile contents at 500 °C and 700 °C. Pyrolysis experiments revealed that below 500 °C mostly tars are formed from Org MSW. Organic MSW and coal 0.5/0.5 blends yielded higher methane concentrations than coal or MSW alone, reaching 35-37 % at 800 °C. It could be concluded that both fixed bed and thermogravimetric method analysis have provided a good result to investigate the gasification and pyrolysis processes

Association of respiratory symptoms and lung function with occupation in the multinational Burden of Obstructive Lung Disease (BOLD) study

Background Chronic obstructive pulmonary disease has been associated with exposures in the workplace. We aimed to assess the association of respiratory symptoms and lung function with occupation in the Burden of Obstructive Lung Disease study. Methods We analysed cross-sectional data from 28 823 adults (≥40 years) in 34 countries. We considered 11 occupations and grouped them by likelihood of exposure to organic dusts, inorganic dusts and fumes. The association of chronic cough, chronic phlegm, wheeze, dyspnoea, forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1)/FVC with occupation was assessed, per study site, using multivariable regression. These estimates were then meta-analysed. Sensitivity analyses explored differences between sexes and gross national income. Results Overall, working in settings with potentially high exposure to dusts or fumes was associated with respiratory symptoms but not lung function differences. The most common occupation was farming. Compared to people not working in any of the 11 considered occupations, those who were farmers for ≥20 years were more likely to have chronic cough (OR 1.52, 95% CI 1.19–1.94), wheeze (OR 1.37, 95% CI 1.16–1.63) and dyspnoea (OR 1.83, 95% CI 1.53–2.20), but not lower FVC (β=0.02 L, 95% CI −0.02–0.06 L) or lower FEV1/FVC (β=0.04%, 95% CI −0.49–0.58%). Some findings differed by sex and gross national income. Conclusion At a population level, the occupational exposures considered in this study do not appear to be major determinants of differences in lung function, although they are associated with more respiratory symptoms. Because not all work settings were included in this study, respiratory surveillance should still be encouraged among high-risk dusty and fume job workers, especially in low- and middle-income countries.publishedVersio