The study deals with the utilization of organic Rankine cycle (ORC) to recover waste heat from compression ignition (CI) engines and produce additional power output. A review on the potential of ...waste heat recovery from exhaust gas, water jackets and intake charge air of CI engines was carried out. Research challenges associated with engine-ORC technology such as selection of organic working fluid, type of evaporator/condenser, back pressure due to additional ORC components in the exhaust line are discussed. The evaporator for the engine-ORC needs to be designed by keeping a view of variable exhaust gas heat source (variable temperature and mass flow rate profiles). It is explored from the literature study that engine-ORC system could operate with the maximum thermal efficiency range about 10–25%. The main reason for low thermal efficiency could be due to lower operating temperatures in the ORC. However, the overall efficiency of combined system (engine and engine-ORC with exhaust gas/water jackets/intake air/use of hot water from condenser for heating/refrigeration application) is significantly higher (60–90%) than the conventional standalone ORC system (10–25%). It is also found that R245fa is the better organic working fluid for engine-ORC application based on better performance, availability, economic and environmental aspects.
•Engine exhaust gas has highest potential of heat recovery than EGR and cooling water.•Thermal efficiency of standalone engine-ORC system is about 10–25%.•Overall combined efficiency of engine and engine-ORC system is about 60–90%.•R245fa is the best suitable working fluid for engine-ORC application.•Shell & tube heat exchangers and Scroll expanders are suitable for engine-ORC.
•Solar thermal bio-refinery technology was demonstrated for biofuels production.•All three pyrolysed products were assessed for their feasibility as fuel candidates.•Pyrolytic zone for Jatropha seed ...biomass was in the range of 203–508°C.•Presence of alkane, ester, alkene, & alkyne groups were confirmed in products.•Maximum of 20% bio-oil, 51% bio-char and 29% pyrolytic gas were obtained.
The present study is focused on conversion of non-edible Jatropha seeds biomass to biofuels i.e., liquid, solid and gaseous fuels via solar thermochemical pyrolysis process. All the three products namely; (i) bio-oil (liquid) (ii) biochar (solid) and (iii) pyrolytic gas were characterized by means of TG (Thermo-gravimetric), FTIR (Fourier transform infrared), GC–MS (Gas chromatography mass spectroscopy), proximate and ultimate analysis; and assessed their feasibility as fuel candidates. It is explored that 20% maximum bio-oil yield was obtained with the average reactor temperature of 250–320°C. The pyrolytic zone for the biomass was identified in the range of 203–508°C. The ultimate analysis of the bio-oil revealed that the oil is rich in carbon (58.3%) and hydrogen (8.7%) with an average chemical composition of CH1.79N0.05O0.40. Relatively lower oxygen content in the bio-oil favors for high heating value. Higher H/C ratio (1.79) and lower O/C ratio (0.4) of the bio-oil indicates its suitability as petroleum fuel for engine applications. The carbon compounds present in the bio-oil are from C7 to C28 which may represent the mixture of diesel and gasoline fuels. Finally, it is emerged from the study that all the three products are exibiting various favorable conditions to be employed as fuel candidates for different applications such as engines and boilers.
•Pyrolysed oil diesel blends (PODB20, PODB40, PODB60) used in a diesel engine.•Efficiency of the engine increased from 32% to 34% & 35.6% with PODB20 and PODB40.•HC, CO and smoke reduced with PODB20 ...& PODB40 whereas slight penalty with PODB60.•NOx initially increased and then decreased with higher share of pyrolysed oil.•In-cylinder peak pressure was higher with PODB20 and PODB40 as compared to diesel.
The paper is aimed to utilize pyrolysed oil (PO) as a fuel candidate in a direct injection diesel engine. Concentrated solar energy was used to produce pyrolysed oil from Jatropha biomass. The pyrolysed oil was upgraded and blended with diesel at 20%, 40%, and 60% shares (PODB20, PODB40, and PODB60). Experimental tests were conducted on a 3.7kW single cylinder compression ignition (CI) engine at different loads with base diesel and PO blended fuels. Experimental results showed the improvement in thermal efficiency of the engine with low percentage of PO shares (PODB20 and PODB40) as compared to base diesel however, it was decreased slightly with high percentage of PO share (PODB60). In-cylinder pressure was increased initially with addition of PO until 40% due to the dominant effect of inherent oxygen content, and then declined with further addition of PO due to the dominant effect of lower heating value and higher density of PO. Ignition delay and combustion duration were increased continually with increasing percentage of PO share. Unburnt hydrocarbons, carbon monoxide and smoke emissions initially decreased with lower PO shares (20% and 40%) due to high combustion temperature and later increased with higher PO share (60%), whereas oxides of nitrogen emission was followed the reverse trends. A clear insight obtained from the study is that blending of PO with diesel to a certain extent (until 40%) is beneficial in terms of higher thermal efficiency and lower emissions (all carbon based emissions) beyond which a slight penalty in the engine performance and emission characteristics was explored.
Contaminants of emerging concern (CECs) are a new class of pollutants that may pose environmental and human risks. Such contaminants are prevalent in the environment as they can't be easily ...eliminated completely by traditional processing of wastewater discharge due to their obstinate nature. Adsorption is one such technique that is efficient, straightforward, convenient, comparatively inexpensive and sustainable for removing CECs from water on a large scale. Many review articles have been published recently on biochar and its composites derived from several agricultural waste sources for the removal of organic contaminants from water by adsorption. However, a detailed mechanistic aspect of adsorption of CECs on various bio-based adsorbents is scarcely reported. Additionally, the regeneration and stability of bio-based adsorbents need specific consideration. The present work collates studies reported in the last couple of decades on bio-based adsorbents and their composites for CEC removal with the aim to provide insights into the mechanism of adsorption, regeneration and stability of bio-based adsorbents to enable researchers to design a bio-based adsorbent for sustainable removal of CECs from water. The advantages and disadvantages of bio-based adsorbents are also argued. In the end, some key recommendations are made to improve CEC removal from water using bio-based adsorbents.
Review of classification, application, the advantages and disadvantages of bio-based adsorbents, possible mechanisms of CECs adsorption, regeneration & stability of bio-based adsorbents. Key recommendations on CEC removal using bio-based adsorbents.
Abstract
The present investigation reviews the potential causes of the novel Corona virus (COVID-19) spread based on various parameters studied. At the onset of COVID-19 pandemic there were number of ...parameters that were believed to be the dominating factor, and the demand of present scenario is to determine the potential variables that enhances the virus transmission. The social distancing is the main weapon to fight against the coronavirus, keeping this in mind the impact of mobility is analyzed. In addition to this the population density and the effect of temperature and humidity is studied on the present pandemic.
Purpose
This study aims to meticulously evaluate the public service value-generation process facilitated by collaborative e-governance services within the framework of the National e-governance Plan ...(NeGP).
Design/methodology/approach
The study formulates a comprehensive research model through a combination of literature review, insights from domain experts and hands-on experience gained from the e-governance project. A conceptual research model was meticulously structured, validated, and interpreted by using a reflective measurement theory. The analytical tool SmartPLS3 was used to assess the proposed model rigorously.
Findings
The analysis of collected data reveals a statistically significant positive correlation between the implementation of collaborative e-governance strategies and the creation of public service value. This relationship is further reinforced by a strong alignment between the perceived aspects of collaborative e-governance, such as responsiveness, transparency and service delivery and their substantial contribution to the enhancement of public service value.
Originality/value
This study contributes to the scholarly discourse by introducing an innovative methodology for assessing public service value through analyzing empirical data from citizen-centric collaborative e-governance projects. It is noteworthy that no prior studies have examined the nuanced concept of public service value in the context of collaborative e-governance.
•Microwave enhanced alcoholysis of algal, jatropha and pongamia oils were achieved.•Chemically activated waste egg shell derived CaO was used as heterogeneous catalyst.•Effect of aliphatic chain of ...alcohol on biodiesel yields was observed.•ZnO-CaO(cesp) was found the best among all.•ZnO-CaO(cesp) has shown good reusability up to 4 cycles without significant loss of catalytic activity.
Microwave enhanced fast and efficient alcoholysis (methanolysis and ethanolysis) of non-edible oils (algal, jatropha and pongamia) is achieved using chemically activated waste egg shell derived CaO (i.e. CaO(cesp)) as heterogeneous catalyst. CaO(cesp) was extracted from waste chicken egg shell and further activated chemically by supporting transition metal oxide. The maximum conversion was achieved using 3wt% catalysts under 700W microwave irradiation and 10:1 alcohol/oil ratio in 6min. Alcoholysis using ZnO activated CaO(cesp) catalyst has shown higher reaction yields in comparison to other modified catalysts. Methanolysis has shown better biodiesel conversion in comparison to ethanolysis. The catalyst has shown longer lifetime and sustained activity after being used for four cycles. Due to more saturated fatty acid content; algal biodiesel has shown improved fuel properties in comparison to other biodiesels.
•3D printed microchannels were fabricated and loaded with synthesized hematite (α-Fe2O3) nanoadsorbent.•The synthesized α-Fe2O3 nanoadsorbent was tested for the removal of fluoride from ...water.•Fluoride removal efficiency of the microchannels was analysed.
3D printed microchannels were loaded with α-Fe2O3 nanoparticles for fluoride removal from water. Devices having 35 microchannels of 2 and 1.5 mm diameter were fabricated and loaded with 4 and 3 g of nanoadsorbent respectively. Hematite nanoadsorbent used shown good fluoride removal efficiency with a defluoridation capacity of 2.5 mg/g (3 mg/L fluoride concentration, 4 g adsorbent, 1 mL/min flow rate at 25 °C and 7 pH). The customized and compact 3D devices could be an alternative for traditional columns being used for effective fluoride removal from water.
Polymer nanocomposites have attracted great attention world wide from both academic and industrial points of view. The material properties of polymers can be enhanced dramatically by incorporating ...layered silicates at fairly low concentrations. The durability of any material depends upon several factors e.g. light, heat, microwaves, mechanical abrasion etc. The study and the effect of these factors on the performance are essentially required to extend the application limits. The durability of polymer nanocomposites has been evaluated under different environments. The present review describes the durability of different polymer nanocomposites mainly under thermal- and photoageing. Biodegradable nanocomposites of different polymers are also discussed briefly.
Coal fires are common and serious problem in most of the coal producing countries of the world. In India, Jharia Coalfield (JCF) has one of the dense surface–subsurface coal fires in the world. The ...paper presents a case study of fire mapping and its propagation dynamics of JCF during 2001 to 2016 using Landsat data at consecutive 5 year interval. The study reveals that there are three distinct zones of fire in JCF viz., Eastern zone (Rajapur, Lodna, Kustore, Eastern Jharia, Bastacola, Chasnala (IISCO) and Bhowrah), Western Zone (Barora area of Shatabdi, Muraidih open cast mines) and Central zone (Kustor, Tisra, Bhulanbarari, Gonudih Khas Kusunda Colliery (GKKC), Sijua and Modidih colliery). The maximum temperature observed from Landsat data in JCF for years 2001, 2006, 2011 and 2016 is 50 °C, 53 °C, 57.5 °C and 56.5 °C, respectively. In the year 2016, the eastern part of JCF was relatively more affected by coal fire than the western part, showing prevalence of major surface and subsurface coal fire. The same trend was maintained from 2001 to 2016. The total fire area is 8.85 km
2
, 9.34 km
2
, 9.78 km
2
, 8.42 km
2
in the years 2001, 2006, 2011 and 2016, respectively. The total fire area is reduced by 0.43 km
2
(from 8.85 to 8.42 km
2
) from 2001 to 2016.
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