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In this study, the potential textile dye biosorption capacity of a low-cost biosorbent (P. animale) was tested as functions of pH, biosorbent type, initial dye concentration, temperature, contact time and biosorbent dosage at batch scale level. The optimal conditions are 2, dried biosorbent, 93.16 mg/L, 45 ◦C, 1440 minutes and 4 g/L for pH, biosorbent type, initial dye concentration, temperature, contact time and adsorbent dosage, respectively. Dried P. animale removed 99.66 % of Remazol Black B (RBB). The isotherm and kinetic models were analyzed for biosorption mechanism and characteristic. According to the results, Langmuir isotherm and pseudo second order kinetic models were compatible with the experimental data obtained for RBB biosorption on algal biosorbent. Also FTIR and elemental analysis were done and resulted that the functional groups on the surface of algae had significant role in biosorption process. The results of this study supported that P. animale is an effective, inexpensive and eco-friendly biosorbent for treatment of textile dye wastewater.

This study was conducted to investigate the effect of different types of organic wastes (grass and newspaper wastes, cow dung and their combination) on physicochemical properties during vermicomposting using Eisenia fetida. Three set-ups were conducted in which three experiments were for composting (controls) indicated as C1 for newspaper waste, C2 for grass waste and C3 for cattle dung and the corresponding replicates for vermicomposting processes for grass and cattle dung were T1 to T7 and mixed of newspaper, grass and cattle dung were T8-T13. A significant difference was detected among weight and number of Eisenia fetida in treatments, which the highest weight and population growth of worms occurred in T7 (60% of newspaper, 30% of cattle dung and 10% of grass waste). Compared to control treatment (without earthworms), vermicomposting treatment resulted in a decrease of organic carbon and C/N ratio after 30 days. Vermicomposting caused significant reduction in organic carbon (3.9-32.8% ) and C/N ratio (7.9–33.6%). The heavy metals degradation was evaluated after 90 days and at the end of the experiment the concentration of As, and Cd significantly decreased. This study clearly indicates that vermicomposting is a suitable technology for bioconversion of newspaper waste, grass clipping and cow dung to valuable material.

The distribution, stocks and fluxes of Mo were examined in a mountainous fir forest in Greece in two hydrological years. In both years, the fluxes of Mo in throughfall were lower than those in bulk deposition implying Mo retention and probably uptake by tree canopies. The Mo concentration was appreciable in soil solution but its fluxes were lower than those in throughfall. The Mo fluxes in both bulk and throughfall deposition were higher than those in litterfall, a finding that stresses the importance of the hydrological cycle for this metal. The Mo concentration in the older twigs in the standing trees were higher than the current year ones most probably due to the existence of dry deposition. The concentrations of total Mo in soils reflected the nature of the sedimentary rocks underlying the soil and increased with depth following the clay concentration gradient. The available (oxalate extractable) Mo in soils ranged from 3% to 14% of the total Mo. In terms of the stocks of Mo, the soil had by far the highest values in both total and available Mo. The needs of the fir plants for Mo uptake are covered by the available Mo in the mineral soil layers, whereas the Mo content in the organic horizon may not be adequate for this purpose.

Wastewater from textile industry is considered one of the major environmental challenges due to the large volume of highly colored, polluted and toxic effluent. This study investigated the treatability of real textile wastewater by pilot-scale anoxic-aerobic Membrane Bioreactor (MBR) system without sludge wasting for operation period of 100 days. The proposed system was investigated under different Internal Recycle (IR) ratios and the impact of IR ratio on Total Organic Carbon (TOC), Total Nitrogen (TN) and Color removals were examined. Under IR ratios between anoxic and aerobic tanks of 0.0, 0.5 and 2.0, the respective average removal efficiency of TN was 20.9%,53.4% and 71.7%, whereas average color removal of 81%, 85% and 88%, respectively was noted. The results indicated that increase of recycle ratio from 0.5 to 2.0 enhanced TN removal to about 71% and color removal to above 85%. The IR between anoxic and aerobic tanks has a significant role in TN and color removal due its effect on the development of bacterial communities. On the other hand, the results indicate over 93% TOC removal, which was independent of IR ratio.