Lignocellulosic bioethanol production employing newly isolated inhibitor and thermotolerant Saccharomyces cerevisiae DBTIOC S24 strain in SSF and SHF

RSC Advances ◽  
2016 ◽  
Vol 6 (29) ◽  
pp. 24381-24390 ◽  
Author(s):  
Abhishek Mishra ◽  
Ajay K. Sharma ◽  
Sumit Sharma ◽  
A. S. Mathur ◽  
R. P. Gupta ◽  
...  

Bioethanol is a renewable alternative to fossil fuels which facilitate energy security and reduce greenhouse-gas emissions.

2021 ◽  
Author(s):  
Azhar Uddin ◽  
Rabia Liaquat ◽  
Ali Abdullah ◽  
Asif Hussain Khoja ◽  
Muhammad Muddasar ◽  
...  

Abstract Global warming has become a major concern as a result of the excessive release of greenhouse gas emissions. An important strategy for achieving carbon neutrality targets is to focus on renewable energy resources. Second generation bioethanol synthesis via sugarcane bagasse (SCB) is another promising approach for the reduction of greenhouse gas emissions. Here in, this study presents the second generation of bioethanol production from sugarcane bagasse with the pretreatment condition adjoined with basic hydrogen peroxide and pressure effect by fermentation using microorganisms Saccharomyces Cerevisiae and Bacillus Subtilis. The results revealed better production through pretreatment at different operational stages through batch fermentation. Different characterization techniques including Scanning Electron Microscopy (SEM), Fourier Transform Infra-Red (FTIR), High Performance Liquid Chromatography (HPLC), and Thermogravimetric Analysis (TGA) results confirmed the better effects of structural changes of hemicellulose, lignin, and cellulose during treatment, weight loss, thermal stability, and higher concentration of the produced bioethanol in the distillate After pretreatment, the conversion of biomass to bioethanol by using Saccharomyces Cerevisiae gives a high production yield (70%), which presents a production of 70g/L from 100g of SCB at the end of 72 h and a yield of bioethanol (0.7g/g) of SCB confirmed through gas chromatography/mass spectrometry qualitative analysis (GC/MS). The pretreatment conditions of alkaline hydrogen peroxide (H2O2) were optimized to the values 3h, 50°C, 60 psi, pH 8.6, and 150 rpm. This study sheds light on the effects of pretreatment conditions for bioethanol production from sugarcane bagasse.


2011 ◽  
Vol 46 (2) ◽  
pp. 1270-1277 ◽  
Author(s):  
Thomas O. Wilson ◽  
Frederick M. McNeal ◽  
Sabrina Spatari ◽  
David G. Abler ◽  
Paul R. Adler

2018 ◽  
pp. 1-14
Author(s):  
Stephan Klasen

Global inequality has been falling in the last 20 or 30 years, mainly because of rising incomes in China, India, and, more recently, also in Africa. That has been good for global justice and poverty reduction, but not for greenhouse gas emissions. Indeed, the majority of growth in emissions since 1990 has taken place in emerging countries. As a result, if global inequality continues to fall, we have to confront the fact that greenhouse gas emissions will continue to rise. There is no easy solution to this problem, since it is very difficult for emerging countries to drastically change their emission pathways. But there are some policies that might help, including, for example, the removal of energy subsidies and a greater focus on air pollution and energy security, both of which are co-benefits of moving away from fossil energy. The question also remains whether more unequal countries emit more or less greenhouse gases. Theoretical arguments in this regard are ambiguous. We find that in poorer countries, higher inequality actually reduces per capita emissions, mainly because it pushes poor people out of the carbon economy and forces them to lead carbon-neutral lives, relying entirely on biomass. However, in richer countries, inequality is associated with rising emissions. Therefore, if we reduce inequality in rich countries, we will also help reduce emissions. But how to think about climate policy? Economists have very much focused on the idea that there is a first best climate policy with a global carbon price, achieved either through an emission trading scheme or a carbon tax. But one should realize that climate policy in practice involves many different initiatives at many different levels. The driving forces of such policies are often the co-benefits such as cleaner air or greater energy security than emission reduction. If we recognize this, then our analysis should focus not on trying to design first best, but unrealistic policies, but rather on studying the interactions between existing policies and on trying to improve their functioning. This will be a much more promising way to tackle climate change than focusing on an unrealistic first best option.


Author(s):  
Hewitt Crane ◽  
Edwin Kinderman ◽  
Ripudaman Malhotra

Of the various alternatives to fossil energy, nuclear power is the most advanced and the best positioned to become a major source of energy. It is also essentially free of CO2 emissions, and if reducing greenhouse gas emissions is truly the highest concern, then we will have to develop nuclear power. Yet developing nuclear power would also pose challenges in terms of waste disposal, and proliferation of nuclear weapons including the risk of a terrorist organization acquiring such weapons. To some environmentalists nuclear power presents a serious, dilemma. Support or opposition to nuclear power is strongly affected by value judgments as well as lack of disseminated information on questions: What happens if there is leakage of nuclear waste someday? To what extent would people and the world be affected? Would we be trading international security for energy security—does nuclear power increase our vulnerability to terrorist attacks? The mixture of clear benefits with outstanding questions currently allows some nations to embrace nuclear power, some to accept it grudgingly, and still others choose to ignore it. Given its availability and environmental benefits, nuclear is an option that cannot be ignored if we are to tackle the energy problem in a serious way. To assume that we can store and safeguard the waste for thousands of years may be hubris, but we come out in favor of developing nuclear technology in part because we already have to store the legacy nuclear waste that has been generated over the last 50 years. Another 60 or so years of waste will represent a marginal addition to that enormous task, but it would buy us badly needed time to carefully develop other energy sources that do not entail net greenhouse gas emissions. Also, we find that many of the concerns raised against the development of nuclear power are vastly exaggerated. For example, as we describe in this chapter, safe storage of the waste does not require 10,000 years: if we use reprocessing technologies, the remaining waste could be rendered benign in a couple of centuries.


2019 ◽  
Vol 13 (3) ◽  
pp. 486-499
Author(s):  
Maryam Doroodi ◽  
Alireza Mokhtar

Purpose The purpose of this paper is to predict the amount of energy consumption by using a suitable statistical method in some sectors and energy carriers, which has shown a significant correlation with greenhouse gas emissions. Design/methodology/approach After studying the correlation between energy consumption rates in different sectors of energy consumption and some energy carriers with greenhouse gas distribution (CO2, SO2, NOX and SPM), the most effective factors on pollution emission will be first identified and then predicted for the next 20 years (2015 to 2004). Furthermore, to determine the appropriate method for forecasting, two approaches titled “trend analysis” and “double exponential smoothing” will be applied on data, collected from 1967 to 2014, and their capabilities in anticipating will be compared to each other contributing MSD, MAD, MAPE indices and also the actual and projected time series comparison. After predicting the energy consumption in the sectors and energy carriers, the growth rate of consumption in the next 20 years is also calculated. Findings Correlation study shows that four energy sectors (industry sector, agriculture, transportation and household-general-commercial) and two energy carriers (electricity and natural gas) have shown remarkable correlation with greenhouse gas emissions. To predict the energy consumption in mentioned sectors and carriers, it is proven that double exponential smoothing method is more capable in predicting. The study shows that among the demand sectors, the industry will account for the highest consumption rate. Electricity will experience the highest rate among the energy careers. In fact, producing this amount of electricity causes emissions of greenhouse gases. Research limitations/implications Access to the data and categorized data was one of the main limitations. Practical implications By identifying the sectors and energy carriers that have the highest consumption growth rate in the next 20 years, it can be said that greenhouse gas emissions, which show remarkable correlation with these sectors and carriers, will also increase dramatically. So, their stricter control seems to be necessary. On the other hand, to control a particular greenhouse gas, it is possible to focus on the amount of energy consumed in the sectors and carriers that have a significant correlation with this pollutant. These results will lead to more targeted policies to reduce greenhouse gas emissions. Social implications The tendency of communities toward industrialization along with population growth will doubtlessly lead to more consumption of fossil fuels. An immediate aftermath of burning fuels is greenhouse gas emission resulting in destructive effects on the environment and ecosystems. Identifying the factors affecting the pollutants resulted from consumption of fossil fuels is significant in controlling the emissions. Originality/value Such analyses help policymakers make more informed and targeted decisions to reduce greenhouse gas emissions and make safer and more appropriate policies and investment.


2019 ◽  
Vol 11 (5) ◽  
pp. 1234 ◽  
Author(s):  
Hee-Hoon Kim ◽  
Seul-Ye Lim ◽  
Seung-Hoon Yoo

Heat accounts for about one-third of the final energy use and it is mostly produced using fossil fuels in South Korea. Thus, heat production is an important source of greenhouse gas emissions. However, using renewable heat that is directly produced from renewable energy, such as bioenergy, geothermal, or solar heat can save energy and reduce greenhouse gas emissions, rather than transforming conventional fuel into heat. Therefore, an energy policy for renewable heat urgently needs to be established. It is such situations that this paper attempts to assess the consumers’ additional willingness to pay (WTP) or the price premium for renewable heat over heat that is produced from fossil fuels for residential heating. To that end, a nationwide contingent valuation survey of 1000 households was conducted during August 2018. Employing the model allowing for zero WTP values, the mean of the additional WTP or premium for one Gcal of heat produced using renewable energy rather than fossil fuels was estimated to be KRW 3636 (USD 3.2), which is statistically meaningful at the 1% level. This value represents the price premium for renewable heat over heat that is based on fossil fuels. Given that the heat price for residential heating was approximately KRW 73,000 (USD 65.1) per Gcal at the time of the survey, the additional WTP or the price premium corresponds to about 5% of that. When considering that the cost of producing renewable heat is still significantly higher than the cost of producing fossil fuels-based heat, more efforts to lower the production costs of renewable heat as well as financial support of the government for producing and supplying renewable heat are needed to ensure residential consumers’ acceptance of renewable heat.


Processes ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 457
Author(s):  
Sergio Peres ◽  
Eduardo Loureiro ◽  
Humberto Santos ◽  
Fabio Vanderley e Silva ◽  
Alexandre Gusmao

Due to climate change problems caused by greenhouse gas emissions generated by fossil fuels and from waste disposition, fuel alternatives for power generation are being extensively researched. Currently, in Brazil and in many countries, wood waste is disposed in landfills. However, due to lignin, one of the major constituents of biomass, which prevents wood waste from suffering microbial degradation, there is no significant mass degradation, even over decades, when landfilled. Hence, landfilling is not a solution to discard wood waste. Hence, one of the solutions to get rid of the great amount of wood waste is to use it as feedstock in waste-to-electricity (WTE) projects. WTE projects are in high demand in the world, as they can replace fossil fuels and they reduce two major environmental problems (greenhouse gas emissions due to the use of fossil fuels and the accumulation of waste in landfills), while generating biofuels and/or electricity. One of the residues that can be used in WTE projects is biomass residue from construction sites (CCbiowaste). CCbiowaste could be converted into gaseous biofuels through pyrolysis or gasification. These gaseous biofuels can be used in Otto engines connected to an electricity generator (gensets) to produce electricity and/or heat (cogeneration applications). Hence, the objective of this research was to characterize (physically, chemically, and energetically) civil construction biomass wastes (CCbiowaste), produced in a residential building construction site in Recife, Brazil, and to use these wastes in a bench-scale gasifier to produce gaseous biofuels at the temperatures of 700 °C, 800 °C, and 900 °C. The gaseous fuels were collected in the gasifier and analyzed in a gas chromatograph equipped with a thermal conductivity detector (TCD) to determine their composition and heating values. The lower heating value (LHV) results varied from 8.07 MJ∙m−3 to 10.74 MJ∙m−3 for 700 °C to 900 °C gasification temperature. These gaseous fuels were tested in an adapted Otto cycle engine connected to an electricity generator to prove the feasibility of this application. The highest total energy per ton of biomass was obtained for mixed wood and Pinus at 900 °C, with approximately 13 GJ∙ton−1. Hence, the use of CCbiowaste can become an option for the reuse of wasted wood instead of simply dumping in a landfill.


2009 ◽  
Vol 20 (4) ◽  
pp. 533-551 ◽  
Author(s):  
R Saidur ◽  
MA Sattar ◽  
H.H. Masjuki ◽  
M.Y. Jamaluddin

This paper presents an analysis of the greenhouse gas (GHG) emissions from refrigeration equipment. The refrigeration equipments use refrigerants such as chlorofluorocarbons (CFCs) and hydrofluorocarbons HFCs, which are believed to contribute the ozone depletion and global warming. Refrigeration equipment thus contributes indirectly through emission due to electricity consumption and directly due to the emission of refrigerants. Greenhouse gas emissions resulting from the burning of fossil fuels are quantified and presented in this paper. The calculation was carried out based on emissions per unit electricity generated and the type of fuel used. The direct emission of refrigerant was calculated based on emission factor and according to the procedure of Environmental Protection Agency (EPA), USA. A study was conducted to evaluate the refrigerant losses to the atmosphere and the CO2 emission from fossil fuels to generate power to run the refrigeration and air-conditioning systems. In this paper, total appliance annual energy consumption by refrigerator-freezer and air conditioner as well as emission has been estimated for a period of 19 years (1997–2015) using the survey data. Energy savings and emission reductions achievable by raising thermostat set point temperature have been calculated for a period of 10 (i.e. 2005–2015) years.


RSC Advances ◽  
2016 ◽  
Vol 6 (71) ◽  
pp. 66847-66869 ◽  
Author(s):  
L. S. Khuong ◽  
N. W. M. Zulkifli ◽  
H. H. Masjuki ◽  
E. Niza Mohamad ◽  
A. Arslan ◽  
...  

Owing to the growing concern over the depletion of fossil fuels and the rising rate of greenhouse gas emissions which will lead to global warming, many researchers are now dedicated to producing biofuels in order to solve the above-mentioned issues.


Daedalus ◽  
2013 ◽  
Vol 142 (1) ◽  
pp. 26-39 ◽  
Author(s):  
Jon A. Krosnick ◽  
Bo MacInnis

Despite efforts by some congressional legislators to pass laws to limit greenhouse gas emissions and reduce the use of fossil fuels, no such laws have yet been adopted. Is this failure to pass new laws attributable to a lack of public desire for such legislation? Data from national surveys support two answers to this question. First, large majorities of Americans have endorsed a variety of policies designed to reduce greenhouse gas emissions; second, policy support has been consistent across years and across scopes and types of policies. Popular policies include fuel economy and energy-efficiency standards, mandated use of renewable sources, and limitations on emissions by utilities and by businesses more generally. Support for policies has been price sensitive, and the American public appears to have been willing to pay enough money for these purposes to cover their costs. Consistent with these policy endorsements, surveys show that large majorities of Americans believe that global warming has been happening, that it is attributable to human activity, and that future warming will be a threat if unaddressed. Not surprisingly, these beliefs appear to have been important drivers of public support for policies designed to reform energy generation and use. Thus, it seems inappropriate to attribute lack of legislation to lack of public support in these arenas.


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