Wastewater has historically been seen as an efficient and economically alternative medium for microalgal biofuels, however, algae currently suffered from low viability and biomass productivity and required pretreatment of wastewater. Anaerobic digestion of kitchen waste (ADE-KW) was characterized as high ratio of nitrogen and phosphorus and contained ample bacteria inside. To optimize treatment methods, here, phosphate supplement, phytohormone GA3 addition and sterilization were individually or interactively employed to promote biomass production of Chlorella SDEC-11 from ADE-KW. Phosphate supplement slightly enhanced biomass production, had no impact on lipid accumulation, and trigged bacterial bloom. Compared to ADE-KW control, sterilized ADE-KW obtained less biomass, while GA3 increased biomass concentration by 1.8 times and improved lipid productivity to the same level of BG11, without bacterial bloom occurring. GA3 also decreased the polyunsaturated fatty acid C18:3 to less than 10% and matched the EN 14214 biodiesel standard. Considering the interactions between nutrient, phytohormone and sterilization, phosphate hindered the promotion of GA3 on algae in ADE-KW, concluding from less biomass when adding P and GA3 simultaneously than that in sole GA3 treatment. However, phosphate and GA3 synergistically facilitated algal growth in sterilized ADE-KW and obtained the highest biomass production. These results indicated that wastewater-borne bacteria benefited from nutrients supplemented, followed by competing with or negatively influencing on algae, which could be avoided by sterilization and be ignored by GA3 addition. Based on energy and nutrient consumption, the sole addition of phytohormone was a suitable, sustainable and economic treatment method for promoting algal growth in wastewater.
Freestanding flexible Si nanoparticles-multi-walled carbon nanotubes (SiNPs-MWNTs) composite paper anodes for Li-ion batteries (LIBs) are prepared employing a combination of ultra-sonication and pressure filtration. No conductive additive, binder or metal current collector is employed. The SiNPs-MWNTs composite electrode material achieves first cycle specific discharge and charge capacities of 2298 and 1492 mAh/g, respectively. To deal with the primary cycle irreversibility, stabilized Li metal powder (SLMP) has been utilized to pre-lithiate the composite anodes. As a result, the primary cycle irreversible capacity loss is reduced from 806 to twenty-eight mAh/g and therefore the first cycle coulombic efficiency is increased from 65% to 98%. The connection between different SLMP loadings and cell performance has been established to know the pre-lithiation process of SLMP and to optimize the development of Si-based cells. A cell containing the pre-lithiated anode is in a position to deliver charge capacity over 800 mAh/g without undergoing the initial discharge process, which enables the exploration of novel cathode materials. It was also acknowledged the SiNPs-MWNTs electrode with 3:2 Si/MWNT ratio exhibits the optimal balance between the high capacity of SiNPs and therefore the high electrical conductivity and structural stabilization quality of MWNTs, resulting in a high rate capability, high specific capacity, and cycle life surpassing the traditional slurry-cast SiNPs electrode. The reversible capacity is 1866 mAh/g (based on the entire composite weight, an equivalent below) at current density of 100 mA/g. After 100 cycles, the electrode retains capacity of 1170 mAh/g at 100 mA/g and 750 mAh/g at 500 mA/g.
Protecting our natural environment has never been more urgent than nowadays. Increase implies a rise in consumption which makes a continuing threat for nature from various pollutants. Our drinking waters indirectly and living waters are directly exposed to the effect of varied wastewaters from industrial activities. To treat these wastewaters effectively a correct method might be membrane filtration because it's a promising method in some ways though membrane fouling remains a limiting factor. During this study vibrational ultrafiltration and therefore the operating parameters were examined so as to supply an answer for reducing membrane clogging. Experiments were administered monitoring operational parameters, vibrational amplitude (Avibr.) and transmembrane pressure (TMP), with model dairy wastewater, for vibratory shear enhanced processing (VSEP) ultrafiltration. Both Avibr. And TMP were gradually adjusted at different levels, which were selected supported our previous research. Permeate fluxes, chemical oxygen demand, total dissolved solids, pH and electric conductivity were measured and membrane rejections were calculated. Analysis of variance was implemented so as to research the consequences for efficiency of each individual operational parameter. Furthermore, calculations are made for clarifying the possible change in specific energy demand as an economic outcome of applied vibration. Results show that membrane rejections might be maximised at a limiting pressure value, as a result, fine-tuning of operational parameters can eventuate far more efficient performance. Summarizing module vibration significantly decreased membrane fouling that's promising for a good wider use of the technology. Acknowledgements: Authors are grateful for the support of the Hungarian State and therefore the European Union (EFOP-3.6.2-16-2017-00010 – RING 2017) and therefore the project Hungarian Science and Research Foundation (OTKA contract number K 115691). Supported by the UNKP-19-2 New National Excellence Program of the Ministry for Innovation and Technology.
Statement of the Problem: The hydrotreating of vegetable oils is nowadays a really promising thanks to produce renewable components of engine fuels. Using reduced nickel-based catalysts for this purpose seems to be very perspective. However, these catalysts are characterized by relatively low stability during the deoxygenation of triglycerides, mainly thanks to the deposition of coke on their surface. For this reason, bimetallic nickel-based catalysts with Ag and Cu promoters were tested and their activities and stabilities were compared. Methodology & Theoretical Orientation: The hydrotreating was performed during a tubular fixed-bed reactor with the co-current flow of a feedstock and hydrogen. Commercially available rape oil was used as a feedstock and Ni, Ni-Ag and Ni-Cu catalysts with γ-Al2O3 support were prepared and tested. Temperatures within the range of 220 – 320 °C, the pressure of 4 MPa, weight hourly space velocity of 1 h-1 and hydrogen to feedstock ratio of 1000 m3•m-3 were used. Findings: For all tested catalysts, the conversion of triglycerides increased with the increasing reaction temperature and therefore the full conversion was achieved for Ni and Ni-Ag catalysts at the reaction temperature of 260 °C and at 280 °C for the Ni-Cu catalyst. The key component of all gaseous products was methane, probably thanks to the strong hydrogenolysis activity of all compared catalysts. Conclusion & Significance: If Ni-Cu/γ-Al2O3 catalyst was used, hydrogenolysis reactions were slightly suppressed and therefore the higher stability at the upper reaction temperatures was observed. For this reason, Ni-Cu/γ- Al2O3 seems to be a perspective catalyst for the hydrotreating of vegetable oils with the aim of the assembly of renewable components of engine fuels.
Background Microtubules in cells are closely related to the growth and metabolism of microalgae. To date, the study of microalgal microtubules has mainly concentrated on revealing the relationship between microtubule depolymerization and synthesis of precursors for flagellar regeneration. While information on the link between microtubule depolymerization and biosynthesis of precursors for complex organic matter (such as lipid, carbohydrate and protein), is still lacking, a better understanding of this could help to achieve a breakthrough in lipid regulation. With the aim of testing the assumption that microtubule disruption could regulate carbon precursors and redirect carbon flow to promote lipid accumulation, Chlorella sorokiniana SDEC-18 was pretreated with different concentrations of oryzalin. Results Strikingly, microalgae that were pretreated with 1.5 mM oryzalin accumulated lipid contents of 41.06%, which was attributed to carbon redistribution induced by microtubule destruction. To promote the growth of microalgae, two-stage cultivation involving microtubule destruction was employed, which resulted in the lipid productivity being 1.44 times higher than that for microalgae with routine single-stage cultivation, as well as yielding a desirable biodiesel quality following from increases in monounsaturated fatty acid (MUFA) content. Furthermore, full extraction of lipid was achieved after only a single extraction step, because microtubule destruction caused removal of cellulose synthase and thereby blocked cellulose biosynthesis. Conclusions This study provides an important advance towards observation of microtubules in microalgae through immunocolloidal gold techniques combined with TEM. Moreover, the observation of efficient lipid accumulation and increased cell fragility engendered by microtubule destruction has expanded our knowledge of metabolic regulation by microtubules. Finally, two-stage cultivation involving microtubule destruction has established ideal growth, coupling enhanced lipid accumulation and efficient oil extraction; thus gaining advances in both applied and fundamental research in algal biodiesel production.
In the developing world, rural population still depends largely on biomass for cooking. Besides, traditional rural artisans making pottery, bell-metal craft, bangles, hand-tools etc. use biomass based furnaces. Decades back, the problem of improving the traditional systems using biomass particularly cook stoves was taken up by selected researchers across the globe with the last decade seeing a sharp increase in the concern over emissions from biomass as health hazards and agents of climate change. Efforts to develop and disseminate clean cooking devices have met with limited success due to several challenges on the ground. Ironically, the impact of large scale exploitation of the forest resources and that of traditional use of biomass have been put in the same basket leading to an undue rejection of this fuel by policy makers while it qualifies to be a fuel for a sustainable future due to its renewable nature, carbon neutrality and decentralized availability. The need of the hour instead is to provide more technical inputs in close engagement with the users along with social awareness and mobilization to result in better technologies acceptable to the user. This has been the focus of work group of researchers at IIT Delhi which has been trying to use scientific methodologies for design and development of a downdraft gasifier cook stove, producer gas burner, pottery kilns, furnaces for bangle making and bell metal craft etc., and (ii) design of testing protocols for cook stoves, hood for emission measurement. Scientific rigor and interaction with the users wherever possible have been at the core of the approach followed. Despite that, there are many challenges in the adoption of the technologies which will be highlighted in this talk. Specific recommendations will be made emphasizing the need for coordinated efforts to make biomass an energy resource for sustainable development. Recent Publications: 1. Sutar K B, Kohli S and Ravi M R (2017) Design, development and testing of small downdraft gasifiers for domestic cookstoves. Energy 124:447-460. 2. Sutar K B, Ravi M R and Kohli S (2016) Design of a partially aerated naturally aspirated burner for producer gas. Energy 116:773-785. 3. Sutar K B, Kohli S, Ravi M R and Ray A (2015) Biomass cookstoves: A review of technical aspects. Renewable and Sustainable Energy Reviews 41:1128-1166. 4. Ravi M R, Dhar P L and Kohli S (2007) Energy audit and improvement of an up draught pottery kiln. SESI Journal 17:70-86. 5. Yadvika, Sreekrishnan T R, Santosh and Kohli S (2007) Effect of HRT and slurry concentration on biogas production in cattle-dung based anaerobic bioreactors. Environmental Technology 28:433-442.
Production of biogas from biomasses and organic residues by anaerobic digestion using methanogenic bacteria is an important biotechnological process for sustainable production of biofuel. One of the limiting factors of this process is the poor conversion rate into biogas of the energy contained in the biomass. This is mainly due to the difficult metabolism of the plant cell wall components by the microbial consortium present in the digestor mainly due to the complexity of cellulose, hemicellulose and lignin. Cellulose is very abundant and its full conversion into methane would increase the efficiency of the process. Biogas production from polysaccharides and other biopolymers occurs through four steps: hydrolysis, acidogenesis, acetogenesis and methanogenesis. It is evident that the importance of a more efficient hydrolysis to get more biogas produced. We developed three heterologous expression systems for production of the following enzymes like endocellulase (endo-glucanase) from Bacillus pumilus; cellobiohydrolase from Xanthomonas sp., beta-glucosidase from Bacillus amyloliquefaciens. These three enzymes are known to participate in the depolymerization of cellulose that occurs in three steps: (i) Cellulose polymer cleavage and oligomers formation; (ii) Removal of dimers (cellobiose) from the cellulose oligomers; (iii) Release of glucose from cellobiose dimers. The three genes encoding the above mentioned enzymes were amplified by PCR, cloned in pTOPO, sequenced to verify the correct amplification, then cloned in pQE, an expression vector giving 6xHis tagged proteins. E. coli M15 was the expression system. The three enzymes were then purified by a single step-affinity chromatography, thanks to the six histidine tag and used in the experiments of cellulose digestion. Considering that two enzymes were not soluble when expressed in E. coli (cellobiohydrolase and beta-glucosidase formed inclusion bodies), an alternative heterologous expression system was taken into consideration for the production of the enzymes, the yeast Pichia pastoris. The final goal of the project is the development of a pretreatment method to be used for the conversion of biomasses and industrial organic residues containing cellulose into a substrate to be fermented by methanogenic bacteria for production of biogas. While the heterologous expression in Pichia is still under development, we already have an efficient system for production of the recombinant bacterial endoglucanase. The optimal conditions for the use of this enzyme have been determined and the optimal pH is 6.0 and the optimal temperature is 400C. In these conditions, pH 6.0 and temperature of 400C, the enzyme maintained up to 50% of its activity after one week. The enzyme was tested on some substrates and was found to be able to depolymerize microfibril cellulose (Sigma), residual short fiber cellulose from paper industry, corn cob powder and corn stalk powder with a specific activity of 251, 142, 75 and 70 IU/mg respectively. The next step will be the measurement of the methanogenic potential of different cellulose-containing organic residues with and without pretreatment with the cellulolytic enzyme. Following this experiment, the economic sustainability of this process will be calculated, comparing the cost of pre-treatment and the benefit achieved in term of increased biogas production.
Biomass is all plant and animal matter on the earth???s surface. Nigeria is blessed with abundant biomass resources that are either currently untapped or inefficiently harnessed. It has been estimated that about one billion metric tons of household waste is generated annually (comprising agro-residues such as rice husks, ground nut shells, corn curbs, sugar cane trash, coconut shells and sorghum stalks). Given those virtually free available huge quantities of biomass resources in Nigeria, the potentials for the development of alternative sustainable biomass based electricity for the development of rural Nigeria is very promising. Globally 1.4 billion people live without any form of commercial energy electricity. The implication of this is due to lack of access to energy and rural economies which cannot grow and develop as expected because of the absence or inadequacies (erratic supply/distribution of conventional energyelectricity) produced by Power Holding Company of Nigeria (PHCN) which still remains an illusion. Therefore, there is an urgent need for a radically different approach to electricity generation, particularly one that appreciates the condition and environment of the poor and their indigenous technology inclusive. Access to electricity is very important because it is the prime mover of all human socio-economic activities. More importantly, the adoption and development of biomass based electricity in Nigeria will enhance the drive towards rural development, electrification and industrialization. It will also promote the development of small scale economic activities which have immense potentials for strengthening poverty alleviation programs of the government, while simultaneously serving as a strategy for promoting a safe and healthy environment and sustainable development in rural Nigeria. Besides, it will assist the states and local governments to counter power outages being experienced and create an atmosphere of competition as well as job opportunities.
This paper designs a globally smart energy frame for zero carbon emission covering electricity, transport, industry, etc. all sectors. Primarily, Carbon-free World Power Grid (CFWPG) is proposed here; converter-train as the pivotal technology is proffered, to construct Inertia-endowed Convert-station and DC Transformer for integrating remote generation, DC transmission, AC local grid and DC sub-grid into CFWPG configuration; supportive technologies including Multi-function Energy Storage are listed; the decisive factors of low-priced electricity are given. In order to prove zero carbon emission fully viable, non-carbon transport methods and carbon-free metal productions are particularly discussed as innovative improvement examples of other sectors. In the future, it is expected that more than 95% energy will be gained through CFWPG; production and energy consumption modes will be upgraded; and low-priced electricity will make carbon consumption become a luxury.
Due to the ever-increasing energy demand, fuel depletion and global climate change, investigation and development of renewable energy conversion and storage devices have increased round the world. Dyesensitized solar cells and supercapacitors are considered clean and environmentally friendly energy conversion and storage devices, thanks to their simple fabrication process and low cost. During this study, in place Ru nanoparticles (Ru-NPs) are prepared on the N-doped template-free mesoporous carbon through the stabilization and carbonization of poly (butyl acrylate)-b-polyacrylonitrile (PBA-b-PAN) block copolymer with Ru (acac)3. Ru-NPs and N-doped porous carbon are formed simultaneously, where PBA-block act as a porous template, while PANblock and Ru (acac)3 acts as semi-graphitic carbon and Ru source, respectively. The resulting Ru-NPs on N-doped mesoporous carbon shows a really high specific gravimetric capacitance of 656.25 F g−1 at a scan rate of 10 mV s−1, good rate capability, and excellent long-term cycling stability (almost 100% retention after 5000 cycles) when applied because the electrode in supercapacitors. Furthermore, it shows excellent catalytic activity toward the cobalt reduction reaction in DSSC, and optical transmittance properties within the visible wavelength (AVT, 42.25%). When Ru-NPs on N-doped mesoporous carbon were employed as CEs during a bifacial DSSC using SGT-021 sensitizer, an interesting power conversion efficiency of 10.13 % and 8.64% from the front and rear illumination, respectively, were obtained. Also, a typical DSSC with the resulting CEs shows a PCE of 11.42%.
Ribonucleic acid (RNA) is of great importance during a wide selection of laboratory tests, especially within the diagnosis of viral, bacterial and parasitic deseases, the diagnosis of hereditary disorders and tumors, also as basic research. To supply relevant and reliable results, the biology teechniques used for such purposes require pure and intect molecules of purified RNA. RNA are often extracted from prokaryotic or eukaryotic organisms, from various heterogeneous materials, such fresh or frozen tissues, cell lines, PCR products or chemically preserved samples for an extended . Therefore, RNA purification becomes a critical step, to get good quality RNA molecules (pure and intact). The primary is predicated on organic extraction using phenol: chloroform. The second group encompasses RNA purification methods through their ability to adsorb at specific salts, and therefore the third groups includes methods that exploit RNA isolation on isopynic gradients. Precisely, the adsorption methods, which are based supported the power of RNA to bind to a selected surface within the presence of chaotropic salts, are one among the foremost available kits on the market, additionally to supply RNA with top quality and purity.
This paper presents a CFD study of a fast pyrolysis process in a pilot-scale auger reactor. By providing a detailed CFD simulation of this reactor, we are capable to obtain a clearer insight into the complex physical phenomena associated with multi-phase flow dynamics, heat transfer and chemical kinetics. The three main products of the process are solid bio-char, condensable vapours and non-condensable gases. Therefore, a multi-fluid model coupled with a chemical solver is a suitable approach for the simulations. The feedstock is a lignocellulosic biomass which composed of cellulose, hemicellulose and lignin. The biomass decomposition is simplified to ten reaction mechanisms. Three different phases that are taken into account are condensable/non-condensable phase or the gas phase as the primary phase, solid reacting phase or biomass phase as a secondary phase and non-reacting solid phase (steel shots) or heat carrier as the other secondary phase. Each phase composed of different species. The results for the product yield shows a good agreement between the CFD results and the experimental data previously received for the simulated reactor. The outcome of this study provides a validated CFD model for industry and researchers that may apply to optimize the operating conditions of the auger reactors in future. Recent Publications: 1. Jalalifar S, Abbassi R, Garaniya V, Hawboldt K A and Ghiji M M (2018) Parametric analysis of pyrolysis process on the product yields in a bubbling fluidized bed reactor. J of Fuel 234:616-625. 2. Papari S, Hawboldt K A and Helleur R (2017) Production and Characterization of Pyrolysis Oil from Sawmill Residues in an Auger Reactor. Ind. Eng. Chem. 56(8):1920???1925. 3. Papari S and Hawboldt K A (2017) Development and Validation of a Process Model To Describe Pyrolysis of Forestry Residues in an Auger Reactor. Energy Fuels 31(10):10833???10841. 4. Aramideh S, Xiong Q, Kong S C and Brown R C (2015) Numerical simulation of biomass fast pyrolysis in an auger reactor. J of Fuel 156:234-242. 5. Jalalifar S, Ghiji M M, Abbassi R, Garaniya V and Hawboldt K A (2017) Numerical modelling of a fast pyrolysis process in a bubbling fluidized bed reactor. IOP Conference Series: Earth and Environmental Science 73:012032.
Numerous independent reports have shown that sustainable investments have not only been more resilient during the covid-19 pandemic, but they are expected to increase. In fact, sustainable investments using ESG (Environmental, Social, Governance) indicators become so popular that the biggest challenge for investors and reporting-solution providers is the ability to benchmark, verify, and cross-communicate this data. Ultimately, these are ‘good problems’ to have in sustainable energy: how do we make investments that yield the best alpha, while providing the most impact.
In the recent attempts to stimulate alternative energy sources for heating and cooling of buildings, emphasise has been put on utilisation of the ambient energy from Ground Source Heat Pump Systems (GSHPs) and other renewable energy sources. Exploitation of renewable energy sources and particularly ground heat in buildings can significantly contribute towards reducing dependency on fossil fuels. Geothermal Heat Pumps (GSHPs), or Direct Expansion (DX) ground source heat pumps, are a highly efficient renewable energy technology, which uses the earth, groundwater or surface water as a heat source when operating in heating mode or as a heat sink when operating in a cooling mode. It is receiving increasing interest because of its potential to reduce primary energy consumption and thus reduce emissions of the Greenhouse Gases (GHGs). The main concept of this technology is that it utilises the lower temperature of the ground (approximately <32°C), which remains relatively stable throughout the year, to provide space heating, cooling and domestic hot water inside the building area. The main goal of this study is to stimulate the uptake of the GSHPs. Recent attempts to stimulate alternative energy sources for heating and cooling of buildings has emphasised the utilisation of the ambient energy from ground source and other renewable energy sources. The purpose of this study, however, is to examine the means of reduction of energy consumption in buildings, identify GSHPs as an environmental friendly technology able to provide efficient utilisation of energy in the buildings sector, promote using GSHPs applications as an optimum means of heating and cooling, and to present typical applications and recent advances of the DX GSHPs. The study highlighted the potential energy saving that could be achieved through the use of ground energy sources. It also focuses on the optimisation and improvement of the operation conditions of the heat cycle and performance of the DX GSHP. It is concluded that the direct expansion of the GSHP, combined with the ground heat exchanger in foundation piles and the seasonal thermal energy storage from solar thermal collectors, is extendable to more comprehensive applications.
As we all know the fact that with the increasing of awareness about the threat on our nature and people are now more familiar about the risk Or danger to our nature and it’s poor condition, there are many social and economic awareness parties as well as all the authorities as well as environmentalists are in worry and Considering all the pollution related challenges and all the parameters that are responsible for this threat and for that purpose they are concerning about the nature and our earth across the globe. This is the reason that now we are looking for some environmental friendly sources and therefore, we are now more depends on renewable energy sources like wind energy, solar energy and hydro energy for the purpose to generate electricity. Now after looking all the possible sources we think that the option for wind energy is safest and best option in terms of balanced development for our Nation and our nature as well as concerning about the mother earth and in the criterion of commercial development. This source is better option than other sources because of its two reasons first are renewability and the second is availability. We need high potential for development as the world’s need for energy is far more than the world’s total consumption of energy. According to the reports across the whole Worldwide, a total need of about 60 000 MW have been installed, which produces about 100 TWH yearly. The biggest and most important challenges for further usage of energy and development and modification are connected to economy, land usage, environment and grid capacity. As we all know that the cost of installations of wind power plants are low that ultimately reduced installation costs, however there is no fuel used and hence no fuel cost and the construction is not very complicated and time consuming and need construction time less than one year, it is said to be the most economic new power plant technology. Man has used the energy in wind for many years for different purposes whether it is, used for sailing the boats or running power generation mills at land. With all the available energy sources we can say that wind energy source is the most mature and is the best option that we are looking forward to for the production of energy in our future. The total effects of wind energy on the environment and our nature it often is positive, because of the production of renewable energy and due to the fact that it has the power of replacing the mining activities that are going around our own world. An overall view, about how that energy source will displace the harm caused by other activities can be understood by more complete understanding of the environmental and economic reactions. So after checking all the criterion of the positive as well as negative sides we may choose wind energy for the generation of energy and other beneficial purposes as it is the safest one option. This research paper provides analyses and discusses all the aspects to understand those environmental effects, both positive and negative. We consider both the effects on our nature and our environment.
Nepal having huge hydro power potential of 83000 MW is using only 1% energy from hydropower (very clean, sustainable and renewable energy resources) .Despite huge potential are untapped and importing power to meet the demand. The gross installed capacity of the country is 900 MW developed within over 100 year’s period from 1911 to till this date and.653 MW is importing from India. Water resources are only one reliable source to generate income from hydropower development for Nepal and can significantly increase the national economy. But unfortunate the nation is depending on the other countries to import the energy. To reduce the economic loss in energy import, hydropower development must be given first priority and the existing plants should be in well operation conditions. To improve the performance of the plant regular performance evaluation should be carried out. With the age of plants the deterioration causes decrease in plant efficiency. To rectify the condition timely evaluation is must. Such that the evaluation enables the decision maker to take action for the improvement of the plants in effective way. This evaluation study is carried out for both existing large and medium plants on the basis of Multi Criteria Decision Analysis (MCDA) which includes energy production profile, self-sufficiency, plant factor, O/M cost, energy generation cost and staff level as evaluation criteria. From the study the energy production cost found high in case of large power plants but they are operation in better conditions than medium power plants. Medium power plants found to be repaired as soon possible.
