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The continuous and rapid growth of sewage sludge (biosolids) from wastewater treatment plants (WWTPs) poses both economic and environmental challenges. In many cities of Russia, the situation has exacerbated with time. In this study, three state-of-the-art biosolid management technologies, namely windrow composting (WC), tunnel composting (TC), and lime stabilization (LS), were evaluated for their economic feasibility to produce commercially biofertilizers from WWTP-derived biosolids. Based on an annual discharge of 22,000 m3 of dewatered biosolids from the case WWTP, about 29,785, 22,453, and 35,056 m3 biofertilizers could be produced through WC, TC, and LS, respectively. Analysis showed the selected WC, TC, and LS technological options to be feasible if the selling price of the produced biofertilizer would be maintained at 19 EUR/m3 for WC and LS, and 77 EUR/m3 for TC. The discounted payback period (DPP) of WC, LS, and TC would be 3.1, 18.1, and 25.3 years, respectively, with an IRR (internal rate of return) of 10%. The key characteristics of the treated WWTP-derived biosolids were found to be good enough to meet the existing environmental laws, standards, and regulations in Russia. From an investment perspective, this study is useful in developing WWTP-derived biosolids for biofertilizer production at enterprise level. [ABSTRACT FROM AUTHOR]

One of the most basic ingredients of fractal or multifractal is its scale-invariance or self-similar property albeit they appear seemingly disordered or apparently bewildering. In this article, we give several examples of deterministic, random and stochastic fractals as well as multifractals to show that there is always at least one conservation law behind all these systems. On the other hand, it is well-known and it has been shown here too that fractals and multifractals are self-similar which is also some form of symmetry that sends the object to itself. This is reminiscent to Noether's first theorem that states that for every continuous symmetry of an action, there exists a conserved quantity. Finding the connection between conserved quantity in fractal and multifractal with scale-invariance of self-similarity can actually be coined as an equivalent counterpart of the Noether's first theorem. [ABSTRACT FROM AUTHOR]

This study examined side-stream generation from Finnish forest industry comprising data from 19 sawmills, 1 plywood mill, 1 particleboard mill, 10 paper and board mills, 1 semi-mechanical mill, and 15 chemical pulp mills. A structured questionnaire survey was carried out for this study. The results revealed that the generation of side stream in sawmills, plywood mills, paper and board mills, mechanical pulp mills, and chemical pulp mills accounted for 42.2%, 56.1%, 23.8%, 30.7%, and 56% of round wood log input, respectively, and 91.2%, 135.5%, 42.2%, 44.7%, and 238.5% of the finished product, respectively. Woodchips, sawdust, and bark were recognized as the significant side streams in sawmills and plywood mills, whereas fiber sludge was found the main side stream in paper, board and mechanical pulp mills. In chemical pulp mills, black liquor was found the greatest side stream, which comprises 43% of the wood input and 183.3% of the finished product. The study estimated that in 2016, Finnish forest industry generated a total 27.7 million tons of side streams, consisting of 49.2% black liquor, 28.5% solid wood-based waste, 14.1% sludge, 4.4% ashes, and 3.8% others. A current use of these side streams and their future utilization potential is also discussed. [ABSTRACT FROM AUTHOR]

The article presents the case study of a young girl with sublingual dermoid. The preoperative diagnosis by Fine needle aspiration cytology (FNAC) of the lump showed that the lump was a lipoma. The lump was excised by intra-oral surgery for better cosmetic results. Histopathological study confirmed that the excised lump was a lipoma of floor of mouth.