In the present work, the ash transformation and deposition behavior during wheat straw and wood waste combustion were investigated by combustion experiments in an entrained flow reactor. The influence of sewage sludge addition on ash chemistry and deposition tendency was also studied. During combustion wheat straw, fine fly ash particles smaller than 2.5 μm are mainly formed due to vaporization...

The research comprised of studying the effect composting sewage sludge with sawdust and vermicomposting with earthworm Eisenia fetida has on the degradation of 16 polycyclic aromatic hydrocarbons (PAHs). Raw rural sewage sludge prior composting was more contaminated with PAHs than urban sewage sludge, in both cases exceeding EU cutoff limits of 6 mg/kg established for land application. Dibenzo[...

The recycling of organic wastes is required from the viewpoint of environmental issues. Sewage sludge makes up about 30% of the organic wastes in Japan, and at present, the ratio is increasing (Study group on bio-waste recycling, 1999); therefore, it is important to treat and utilize the sewage sludge. Conventional treatment methods such as land filling and ocean dumping have been regulated to ...

Heavy metals (HMs) in sewage sludge have become the crucial limiting factors for land use application. Samples were collected and analyzed from 32 waste water treatment plants (WWTPs) in the Shanxi Province, China. HM levels in sewage sludge were assessed. The multivariate statistical method principal component analysis (PCA) was applied to identify the sources of HMs in sewage sludge. HM pollu...

The step of maturation (around 60 days) appeared less active as compared to the first step of pre-fermentation (around 90 days) since the values of temperature, recorded during the second step of maturation, are found generally less important than those recorded during the first step. A similar tendency of C/N ratio values decrease is generally observed in the two piles of wastes during the two...

Biosolids are solid, semi-solid, or liquid materials resulting from the treatment of domestic sewage sludge. The term “biosolids” was introduced by the wastewater treatment industry in the early 1990’s and has been adopted by the United States Environmental Protection Agency (U.S. EPA) to distinguish high quality, treated sewage sludge from raw sewage sludge and from sewage sludge containing la...

the effects of waterlogging, sewage sludge and animal manure on the concentrations of dtpa extractable copper, iron, manganese and zinc were investigated in two different types of soil. a factorial experiment based upon a completely randomized design of two replications containing duration of waterlogging at six levels (0, 1, 3, 7, 15, 30 days), source of organic fertilizer at three levels (con...