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- Urban water reuse in tourism areaPublication . Albuquerque, António; Matos, J.Over the past decades, treated wastewater (reclaimed water) has been used as an alternative to potable water for a range of uses such as irrigation (landscapes, golf courses, and agricultural fields), aquifer recharge, industry applications, stream flow feed- ing, and nonpotable urban applications. In that period, there have been significant advances in reuse technologies, and an increase in the implementation of either rules or guidelines for water reuse. Tourism generates one of the biggest pressures on water needs that coincides with the necessity to manage decreasing water resources more efficiently. As tourism areas continue to grow, pressure on local water sources will continue to increase and significant environmental, economic, and social impacts can arise where local freshwater supplies are limited or are available only with large capital investment. The integration of water reuse in water management strategies will contribute to reducing discharges to receiving waters and reducing reliance on natural water sources to meet water demands. In tourism areas, there are several opportunities for reusing reclaimed water produced from domestic wastewater, stormwater, and graywater. Urban waters can be treated through a variety of physical, chemical, and biological processes in order to produce final reclaimed water for dis- charging into a water stream or for reuse.
- The influence of evapotranspiration on wastewater constructed wetland treatment efficiencyPublication . Albuquerque, António; Bialowiec, Andrzej; Randerson, PeterOwing to low investment and maintenance costs, there has been a growing interest in applying plants in wastewater treatment. Plants commonly used in constructed wetlands (CW) include: cattail, reed, rush, yellow flag, manna grass, and willow. In a CW, application of plants brings several benefits: creating aerobic conditions in the otherwise anaerobic rhizosphere, providing carbon compounds into the rhizosphere, uptaking pollutants (e.g. nutrients and heavy metals) from treated wastewater; improving the hydraulic conditions of wastewater flow through CW beds, and also increasing the available surface for growth of microbial biofilms. Hydrophytes also have great transpiration potential. Numerous studies have shown the importance of evapotranspiration during hot periods in natural wetlands and also in constructed wetlands. Evapotranspiration affects treatment efficiency in CWs: it increases the concentration of dissolved compounds due to decreasing water volume. Therefore, having regard to the mode of operating (VSSW or HSSW), temperature and influent characteristics (e.g. HLR and wastewater influent loads), the removal efficiency calculated as a comparison between initial and final concentration is lower, than expected from mass balance. Given results from systems in colder (Poland) and warmer (Portugal) climate conditions shows that the difference in methodology of removal efficiency calculation is significant, even if the CWs are operating in different modes. Usually, in the literature removal efficiency is expressed on the basis of concentrations, mostly due to lack of flow rate monitoring. Unfortunately, this may seriously underestimate treatment performance of CWs. This study suggests the need for routine monitoring of flow rate, or evaluation of potential evapotranspiration, to estimate removal efficiency of a CW based on mass balance.
- Hydroponic System: A Promising Biotechnology for Food Production and Wastewater TreatmentPublication . Prazeres, Ana R.; Albuquerque, António; Luz, Silvana; Jerónimo, Eliana; Carvalho, FátimaSeveral regions of the world are suffering from water scarcity and available water pollution. Mediterranean countries (such as Portugal, Spain, Italy, Greece, Tunisia, Israel, and Jordan) do not meet the requirements in terms of quantity that have been increasing in the last decades for the various sectors, due to lack of water resources, winters with low rainfalls, and summers with hot and dry conditions. Agriculture is the leading water-consuming sector (70%–80%), followed by industry and domestic use. However, industrial and domestic uses are considered priorities, conditioning the amount of accessible water for the agriculture sector. the use of reclaimed water should be considered in the integrated water management system to avoid damages to the environment (surface and underground water, soil, fauna, and flora) and public health. The use of wastewater for irrigation should be carefully investigated and planned in terms of proper treatment, treated wastewater quality, volume of treated wastewater used, application method, physicochemical characterization of soil, nutritional needs of plants, distance to existing water sources, risk of animal and human contamination, and others. Environmental and economic gains can be achieved by reusing wastewater if the study, planning, and application are performed in a sustainable basis.
- Cork Boiling Wastewater Treatment in Pilot Constructed WetlandsPublication . Gomes, A.C.; Stefanakis, Alexandros; Albuquerque, António; Simões, Rogériomost studies published on the topic of cork boiling wastewater (CBW) treatment or valorization used physico-chemical treatment options rather than biological processes. However, the related costs are high and above those of the biological treatment alternative for wastewaters with similar organic loads but from different sources. Thus, con- structed wetland systems (CWs) can be an alternative to conventional biological treatment systems, namely to activated sludge systems, with the prominent virtues of low construction and operation costs. Until today, there is no study or research published for the treatment of CBW using CW systems. Thus, this investigation is a novelty and included the monitoring over a period of four years of the operation of a horizontal subsurface flow constructed wetland (HSF CW) microcosm-scale system planted with common reeds (Phragmites australis) and filled with light expanded clay aggregates (LECA), as support media for the plants and for biofilm development. The contribution of plants to the treatment was assessed by the comparison with an identical wetland unit without plantation (control bed). After this extended period of operation intended to maximize biomass development and acclimatization, which included stepwise increase of the organic load rate (OLR) up to 8.9 g COD/m2/d, the assessment of the treatment capacity of the system was done by doubling the OLR to 16.4 g COD/m2/d during 200 days.