There is a need for the development of on-site wastewater treatment technologies suitable for “dry-process industries,” such as the wood-floor sector. Due to the nature of their activities, these industries generate lower volumes of highly polluted wastewaters after cleaning activities. Advanced oxidation processes such as Fenton and photo-Fenton, are potentially feasible options for treatment of these wastewaters. One of the disadvantages of the Fenton process is the formation of large amounts of ferrous iron sludge, a constraint that might be overcome with the use of nanoscale zero-valent iron (nZVI) powder. Wastewater from a wood-floor industry with initial COD of 4956 mg/L and TOC of 2730 mg/L was treated with dark-Fenton (nZVI/H2O2) and photo-Fenton (nZVI/H2O2/UV) applying a 2-level full-factorial experimental design. The highest removal of COD and TOC (80% and 60%, resp.) was achieved using photo-Fenton. The supply of the reactants in more than one dose during the reaction time had significant and positive effects on the treatment efficiency. According to the results, Fenton and mostly photo-Fenton are promising treatment options for these highly recalcitrant wastewaters. Future investigations should focus on optimizing treatment processes and assessing toxic effects that residual pollutants and the nZVI might have. The feasibility of combining advanced oxidation processes with biological treatment is also recommended.

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In the present study, we investigated the possibility of treating oak wood leachate with a combined ozone and biological treatment. Wood leachate is characterized by high amounts of organic carbon and is reported as being toxic to aquatic organisms. Ozone was used as a pre‐treatment before using aerobic degradation. The biological treatment was applied for seven days and evaluated using head‐space respirometry. Target pollutant in this investigation was polyphenols in combination with more general parameters, such as chemical oxygen demand (COD), total organic carbon (TOC) and colour. A custom made bubble column reactor was used, 1.5 L of wood leachate was exposed to 0–4 g/L of ozone, corresponding to a specific ozone dose between 0.7–7 g/L O3/g of initial COD. Oak wood leachate was found to be easily degraded by ozone, with >90% of polyphenols degraded. COD was degraded by 73%, TOC by 61% and colour by 97% by ozone. Furthermore, a positive correlation between biodegradation and ozone pre‐treatment was found.

The efficiency of biological treatment systems in degrading organic matter is affected by both the available nutrients and the efficiency of the microbial organisms that carry out the degradation. This study assesses whether a wetland treatment system treating stormwater from a wood industrial site faced nutrient deficiency or lacked efficient microbes, and whether addressing these possible problems could enhance the degradation of organic matter in the system. The stormwater was a mix of industrial stormwater, irrigation water and leachate from woodchip piles. The industry mainly processes pedunculate oak, which is known to create a leachate high in polyphenols. This water is currently treated in a pilot-scale wetland system and an aerated lagoon. To study whether the treatability could be enhanced by addition of nutrients (phosphorus, nitrogen, micronutrients), headspace respirometry was used. The effect of adding microbes from a paper mill activated sludge system was also evaluated. Our results showed that all nutrient additions had a positive effect on the treatability of the stormwater. In particular, the addition of nitrogen showed a 12% rise in chemical oxygen demand reduction over 336 h. However, addition of paper mill activated sludge did not enhance the degradation of organic matter; instead, a toxic effect of the stormwater was shown.

The increasing quantity of solid waste is one of the serious environmental problems in Sagarmatha National Park trekking route. Tourists, trekkers and mountaineers litter the route with plastics, cans, bottles, papers etc. on trails. The lodges, hotels and restaurants also do not have better solutions. The trekking routes from Lukla to Everest Base Camp are littered by more than 30,000 visitors coming to the region within a year. The main reason is due to the concentration of the studies of solid waste mainly in urban areas, lack of environmental awareness and public as well as local participation, lack of understanding of the complex mountain ecosystem and negligence of long term impact to tourism industry.´There have been various initiatives and researches carried out by Sagarmatha National Park (SNP), Sagarmatha Pollution Control Committee (SPCC), Nepal Mountaineering Association (NMA), Ev-K2-CNR and various other agencies including NGOs despite which the situation still remains to be resolved and demand further improvement. This paper describes the observations study on SWM carried out during the trekking by Nepalese and Swedish researchers in April 2010 and recommendations drawn out from the study. The issues raised and the problems identified during the study would need to be properly addressed, which would be instrumental in finding way forward and augment the planning of the daunting tasks of Solid Waste Management in the region.