• Energy Research
• 2016-2025close
• 6. Clean water close
• Energy Procedia close

Abstract The impact of CO 2 leakage from underground storage formations on shallow water resources is a concerning aspect in CO 2 capture and storage (CCS) risk assessment. In Campo de Calatrava region (Spain), natural CO 2 fluxes from the Earth’s mantle interact with shallow aquifers, resulting in significant changes in their physical and chemical properties. The resultant water is slightly acidic (pH 5.9-6.4), oxidizing, and enriched in iron (up to 6.1×10 -4 mol·L -1 ) and other metals usually found at trace concentrations. Thermodynamic calculations reveal that aqueous Fe(III) carbonate complexes play an important role in the persistence of this high concentration of iron and trace metals in solution.

Abstract Evaluating and monitoring the CO 2 behavior in the reservoir, understanding the mechanism of CO 2 flow and distribution in the water-CO 2 mixture state is essential. In this study, measurement of the complex electrical impedance ( Z ) and P-wave velocity ( V p ) is conducted during the CO 2 injection into the rock core under the reservoir condition. Specimen is low permeable sandstone and injection rate is ultra-low (in the low capillarity number (C n ) area) to high. In addition to measuring Z and V p , differential pressure on the both sides of the specimen and CO 2 saturation (S CO2 ) of the entire specimen are measured. The change of Z and V p are observed according to the change of differential pressure and S CO2 . After the injection test, S CO2 in cross-section of the specimen is estimated using Archie's law and Gassmann's equation (Patchy saturation model) to the experimental results.

Underground Pumped Storage Hydropower (UPSH) is an alternative to manage the electricity production in flat regions. UPSH plants consist of two reservoirs of which at least one is underground. For this last reservoir, abandoned mines could be considered. UPSH related activities may induce hydrochemical variations, such as the increase of the oxygen (O2) partial pressure (pO2), which may entail negative consequences in terms of environment and efficiency, especially in coal mined areas where the presence of sulfide minerals is common. This work assesses the main expected environmental impacts that UPSH using abandoned coal mines may induce. © 2017 The Authors. Published by Elsevier Ltd. E. Pujades and A. Jurado gratefully acknowledge the financial support from the University of Liège and the EU through the Marie Curie BeIPD-COFUND postdoctoral fellowship programme (2014/16 and 2015/17 fellows from “FP7-MSCA-COFUND, 600405”). This research has been supported by the Public Service of Wallonia – Department of Energy and Sustainable Building. Peer reviewed

Abstract Municipal solid waste (MSW) disposal is one of the main issues towards sustainable development in Malaysia. Current practices for MSW disposal such as landfilling and incineration poses a serious problems on the environment and health. Therefore a significant efforts have been made to utilize MSW for energy source by employing gasification process. However, the MSW is characterized by its high moisture content and low high heating value (HHV) which lowering the energy efficiency. In order to overcome this problems, torrefaction can be used as pretreatment method to remove the moisture content and upgrading MSW properties. The objective of this work is to study the effects of torrefaction temperatures ranging from 240 to 330°C for residence time of 30 minutes on two types of MSW namely food waste and wood waste. The torrefied MSWs are characterized in terms of ultimate analysis, proximate analysis and HHV. The mass and energy yields are also performed for both MSW. Based on the torrefaction, it was found that both food waste and wood waste show an increment on the weight percentage of C contents and decrement on the weight percentage of H and O content which resulting into reduce O/C ratio as the temperature is increased. The HHV for both food waste and wood waste are also increased after torrefaction between 240 and 330°C. The mass yield and energy yield were found to decrease with an increase in the torrefaction temperature. This suggests that torrefaction can be used as an effective MSW pretreatment and the torrefied MSW is more suitable to be used as fuel in gasification process.

Much effort has been put in tightening the building regulations. Though, the energy usage for domestic hot water stayed unchanged constituting a bigger share of the energy pie over the years. Due to the cost, timeframe, and workload associated with instrumentation and installation, the vast majority of the DHW measurements are limited to the household level. This paper introduces a high resolution measuring technique for DHW consumption and its application in a single family house. By applying this technique, we are able to measure the duration, flow and temperature of each water draw event in the house and thus create both the temporal and spatial DHW consumption profiles. The results indicated that the duration of draws varies significantly between tapping places, i.e. the draws in the shower and in the kitchen have an average duration of 300 sec. and 20 sec., respectively. The high resolution metering system was able to record the inefficient use of DHW, at periods when the water temperature was not meeting the users’ requirements, e.g. the wasted energy at the shower depending on the usage patter varies between 25% and 42%. The measured temperature range of DHW in the household is between 52°C (kitchen) and 21°C (sink in utility room).

Abstract A feasibility study was conducted on using solar energy in a conventional tri-generation system for sewage treatment plant application. Generally conventional CHP/CCHP systems can improve the biogas utilization efficiency, however, the waste heat from the power engines is limited for the digester thermal insulation most time in some colder areas, and the additional natural gas is consumed for supplement. This paper proposes a biogas and solar energy-assisted tri-generation system that upgrades the caloric value of biogas before combustion by introducing a thermochemical conversion process. The hourly dynamic energy performances of the proposed and reference systems were simulated by the established mathematic models under Tibet Lhasa weather data. Using solar energy not only reduces the dependence on the external fossil fuel, but also increase the output electric power and cooling energy. The saved natural gas in the whole year can reach 142,757 Nm3. This study may provide a new way to efficiently use the solar energy to improve the energy performance of tri-generation systems.

Abstract The presented technology is aimed on the one hand at purifying the effluents from fermented sludge to the quality enabling their discharge to a river, and on the other hand at ensuring the production of high concentrations of algae biomass. The produced algae biomass will be used as a substrate in the process of methane fermentation. The main factor which minimizes the possibility of introducing crude effluents into photobioreactors is a high content of organic compounds and the suspension. The removal of these contaminants from wastewater will proceed with both physical methods via floatation and biological methods with the use of a biofilm. It is expected that biogenes will be effectively removed from effluents through the growing biomass of microalgae.

Abstract The aim of this study was to verify the effect of Ag and Pt with different loadings (0.1 and 0.5wt.%) as dopants on TiO2for the degradation of a mixture of five parabens through photocatalytic ozonation. The effect of the treatment on the mixture toxicity over different species was also analyzed. The best catalyst in terms of parabens degradation was 0.5%Ag-TiO2.The decrease of metal loading on TiO2 decreased the parabens degradation efficiency as well as COD and TOC removal. Also this decrease has a slight effect over the treated solution toxicity over the different species tested.