Search results for " Monitoring"
showing 10 items of 3129 documents
Microalgae-bacteria consortia in high-rate ponds for treating urban wastewater: Elucidating the key state indicators under dynamic conditions
2020
[EN] On-line performance indicators of a microalgae-bacteria consortium were screened out from different variables based on pH and dissolved oxygen on-line measurements via multivariate projection analysis, aiming at finding on-line key state indicators to easily monitor the process. To fulfil this objective, a pilot-scale high-rate pond for urban wastewater treatment was evaluated under highly variable conditions, i.e. during the start-up period. The system was started-up without seed of either bacterial or microalgal biomass. It took around 19 days to fully develop a microalgal community assimilating nutrients significantly. Slight increases in the biomass productivities in days 26-30 sug…
Internal leachate quality in a municipal solid waste landfill: Vertical, horizontal and temporal variation and impacts of leachate recirculation
2008
The aim of this study was to monitor and characterise internal leachate quality at a Finnish municipal solid waste landfill (Lahti, Kujala, in operation for approximately 50 years) to provide information about its horizontal and vertical variation as well as effects of leachate recirculation on leachate quality. The study area (approximately 4h) of the landfill had 14 monitoring wells for leachate quality monitoring over a 2-year period. The leachate was monitored for COD, BOD, TKN, NH4-N, Cl, pH and electric conductivity. The results showed high horizontal and vertical variability in leachate quality between monitoring wells, indicating that age and properties of waste, local conditions (e…
Greening MSW management systems by saving footprint: The contribution of the waste transportation.
2018
Abstract Municipal solid waste (MSW) management constitutes a highly challenging issue to cope with in order of moving towards more sustainable urban policies. Despite new Standards call for recycling and reusing materials contained in the urban waste, several municipalities still use landfilling as a waste disposal method. Other than the environmental pressure exerted by these plants, waste transportation from the collection points to the landfill needs a specific attention to correctly assess the whole burden of the waste management systems. In this paper, the Ecological Footprint (EF) indicator is applied to the actual MSW of the city of Palermo (Sicily). Results show that the effects pr…
Efficiency of wastewater treatment facilities: The influence of scale economies.
2018
The water cycle, from catchment to discharge, is a sector that involves an important investment and operation and maintenance costs. In particular, sewage treatment is a challenge for governments because they are having to consider economic, environmental, and social aspects. Within the European Union, implementation of Directive 91/271/EEC is responsible for the location of wastewater treatment facilities in the territory, due to the requirement that all urban areas must have this infrastructure to reduce the environmental impact of treated water in water bodies. Different sizes of municipalities affect the design of each wastewater treatment plant (WWTP) and cause variations in the operat…
Economic development and agriculture: Managing protected areas and safeguarding the environment
2017
Abstract The establishment of protected areas has been one of the most important interventions to protect biodiversity from the threat of human activities and in particular from the agricultural traditional activities where they have been restricted at the expense of the economy of the territory sparking in literature a heated debate between those who argue the these hinder the socio-economic development and on the other hand are those who argue that is able to advance social welfare. On the basis of these considerations, the weight of agricultural sector of a country is highly linked to the percentage of protected areas even though the trend of the weight of agriculture in the overall econ…
The influence of solid retention time on IFAS-MBR systems: Assessment of nitrous oxide emission
2017
The aim of the present study was to investigate the nitrous oxide (N2O) emissions from a moving bed based Integrated Fixed Film Activated Sludge (IFAS) - membrane bioreactor (MBR) pilot plant, designed according to the University of Cape Town (UCT) layout. The experimental campaign had a duration of 110 days and was characterized by three different sludge retention time (SRT) values (â, 30 d and 15 d). Results highlighted that N2O concentrations decreased when the biofilm concentrations increased within the aerobic reactor. Results have shown an increase of N2O with the decrease of SRT. Specifically, an increase of N2O-N emission factor occurred with the decrease of the SRT (0.13%, 0.21% …
Determination and assessment of mercury content in calcareous soils.
2009
Abstract This paper provides the first available information on the determination of the total mercury content in different Mediterranean calcareous soils by thermal decomposition, amalgamation and atomic absorption spectrophotometry. Fifty-three samples from five soil use groups (natural, dry land, greenhouse, irrigated and rice farming soils) were analysed. The results show that the levels of mercury in these soils were 9.4–1585 μg kg −1 . Soil organic matter and the zinc equivalent index have been related to Hg content in soils, suggesting that Cu, Ni, Zn and Hg are of a similar origin. The background level (BL), geochemical baseline concentrations (GBC) and the reference value (RV) were…
The distribution of phthalate esters in indoor dust of Palermo (Italy).
2013
In this work, phthalic acid esters (PAEs): dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate, benzyl butyl phthalate, bis(2-ethylhexyl) phthalate, and di-n-octyl phthalate in indoor dust (used as passive sampler) were investigated. The settled dust samples were collected from thirteen indoor environments from Palermo city. A fast and simple method using Soxhlet and GC–MS analysis has been optimized to identify and quantify the phthalates. Total phthalates concentrations in indoor dusts ranged from 269 to 4,831 mg/kg d.w. (d.w. = dry weight). The data show a linear correlation between total PAEs concentration and a single compound content, with the exclusion of the two …
Polychlorinated biphenyls and some pesticides in perch (Perca Fluviatilis) from inland waters of Latvia
1999
Polychlorinated biphenyls (PCBs), DDT - related substances, hexachlorocyclohexane (HCH) isomers and hexachlorobenzene (HCB) were analysed in perch (Perca fluviatilis) from Latvian lakes and rivers. DDE is present in the highest concentrations in all samples; 62–170 ng/g lipid weight in perch from rural areas and 460 ng/g in perch from the Riga area. Individual dominating PCB congeners were in the range 16–45 ng/g and 200–210 ng/g, respectively. The degree of contamination of rural areas in Latvia of these organohalogen substances is in the same range as in background areas in Sweden. Riga, the major urban area in Latvia, is shown to be more polluted with PCBs than other areas in Latvia.
Strawberry fields forever: That is, how many grams of plastics are used to grow a strawberry?
2020
Abstract In important areas of the agricultural sector, plastic is one of the most important tools for improving the managerial and economic performance of companies. Horticultural production under protected cultivation, in particular, makes abundant use of plastic polymers—polymers that mostly turn into waste. This study aims to identify similar organisational models among farmers operating in the strawberry production sector in relation to their intention to recycle plastic material and which factors characterize these models (attitudes, subjective norms, perceived behavioural control, and socio-demographic characteristics) and to quantify the plastic used in relation to the different typ…