RESUMO
Solid waste is considered one of the major pollutants of both water and surface worldwide. The growing global population, urban expansion, and industrial growth are the main reasons for solid waste generation. This has become a major challenge with both regional and worldwide consequences. The yearly generation of municipal solid wastes around the world is 2.01 BT (billion tons) among which about 33 % are not ecologically handled. To address this, proper solid waste management, especially recycling waste products, is crucial to achieving sustainability. High-income countries are able to recycle 51 % of their waste, while low-income countries only recycle 16 % of their waste. Inadequate solid waste management practices can only compound environmental and social problems. To handle these issues thermochemical and biochemical methods are used to convert solid waste to energy. Thermochemical method is suitable for developing countries though it is energy extensive. This review provides a detailed analysis of developing countries' solid waste management and energy recovery. It explores energy recovery technologies, including thermochemical and biochemical waste conversion processes.
RESUMO
Spatial distribution and pollution assessment of selected heavy metals such as barium (Ba), chromium (Cr), nickel (Ni), lead (Pb), vanadium (V), arsenic (As), zinc (Zn), and copper (Cu) in sediments of the Brahmaputra River watershed in Bangladesh was investigated. The mean abundances (ppm) of heavy metals in sediment samples were in decreasing order Ba (375.60) > V (67.60) > Cr (54.10) > Zn (48.20) > Ni (22.28) > Pb (20.25) > Cu (7.59) > As (4.21). Concentrations of Pb and As in the sediments are enriched relative to the average upper continental crust composition, while Ba, V, Cr, Zn, Ni, and Cu decrease considerably. A higher concentration of Pb and Ni indicates that Brahmaputra River watershed samples receive a significant contribution from anthropogenic sources of heavy metals. Chromium displays marked positive correlation with V (r = 0.91, p = < 0.01), inferring a similar source materials input into the watershed. The geo-accumulation index (Igeo) values suggest that the sediments were uncontaminated to moderately contaminated by Ni, Zn, Pb, V, and Cr, whereas moderate to heavily contaminated by As and Cu. The contamination factor (CF) confirmed that sediments in the watershed were moderate to highly contaminated by As, Cu, and Cr. The pollution load index (PLI) values for most of the samples were over one (> 1), indicating an advanced decline in the watershed sediment quality. The overall results of a multivariate statistical analysis suggest that Ba, V, Cr, and Zn contents were all-natural sources, and Pb, Ni, As, and Cu were derived from both natural and anthropogenic sources.
Assuntos
Arsênio , Metais Pesados , Poluentes Químicos da Água , Rios , Sedimentos Geológicos/análise , Arsênio/análise , Monitoramento Ambiental/métodos , Níquel/análise , Bário/análise , Cobre/análise , Vanádio/análise , Bangladesh , Chumbo/análise , Poluentes Químicos da Água/análise , Medição de Risco , Metais Pesados/análise , Cromo/análise , Zinco/análise , ChinaRESUMO
During the last years tremendous changes have occurred in the epidemiologic knowledge and the diagnostic process of the prostatitis syndrome. A new worldwide-accepted classification system has become the gold standard in contemporary literature. The aim of this study was to compare the inflammatory and infectious status of men with prostatitis syndrome with results from our study cohort from 1992. A total of 168 symptomatic men (mean age 43.2 years; range 18-79) attending the Giessen prostatitis outpatient department were included. All men underwent a standard four-glass-test including leucocyte analysis in all specimens. A routine search for Ureaplasma urealyticum and Chlamydia trachomatis was performed. Ejaculate analysis following World Health Organization (WHO) criteria has been performed including the evaluation of increased number of peroxidase-positive leucocytes (PPL). Men were classified according to the National Institutes of Health (NIH) prostatitis classification. The distribution of patients according to NIH criteria is as follows: NIH II (4.2%), NIH IIIA (31.5%), NIH IIIB (50.0%) and urethroprostatitis (14.3%). Chlamydial infection was present in one man (0.6%). Only two men with increased leucocytes in prostatic secretions demonstrated > or =106 million ml-1 PPL in semen. As compared with our cohort study 10 years ago, the proportion of the different subtypes of the prostatitis syndrome have remained stable. The aetiological spectrum of chronic bacterial prostatitis has not changed whereas, in contrast, the prevalence of C. trachomatis now is found to be strikingly reduced. Using the WHO cutpoints for leucocytospermia the inclusion of seminal leucocytes to the diagnostic process has not influenced the distribution between inflammatory (type NIH IIIA) and noninflammatory (type NIH IIIB) chronic pelvic pain syndrome.