-
Process Optimization of Bioethanol Production by Stress Tolerant Yeasts Isolated From Agro-Industrial Waste
Md. Fakruddin,
Md. Ariful Islam,
Monzur Morshed Ahmed,
Nayuum Chowdhury
Issue:
Volume 2, Issue 4, July 2013
Pages:
133-139
Received:
15 May 2013
Published:
10 July 2013
Abstract: The need of Bioethanol or biofuel is increasing worldwide day by day due to renewable resources and ease of production form cheap raw materials. There are several factors that affect on bioethanol production by using yeast. The main objective of this research work was to isolate stress tolerant yeast from agro industry and optimize a process for ethanol production by considering all the factors. Several fermentation batches were carried out by 3 stress tolerant strains varying temperature, pH, sugar concentration, aeration, immobilization and metal ions. From different experiments it was found that temperature 30°C, reducing sugar concentration ranged between 5-6%, pH between 5.0 - 6.0 and shaking condition were optimum for maximum yield of ethanol by strains Saccharomyces unisporous (P), Saccharomyces cerevisiae (C) and (T).The Bioethanol production capacity of yeasts were found P -15.00%, C -12.50% and T – 10.15%at pH 6.0, 30oC temperature in media with 5.5% initial reducing sugar concentration in shaking condition (115 rpm).Pilot scale ethanol production by P strain was 13.10%, C strain 11.15% andT strain 9.80% at 60 hours. Immobilized cells were produced more ethanol than free cells with same culture conditions. Effect of potassium, magnesium, chromium and boron was investigated on ethanol production. Potassium, Magnesium was shown stimulatory effect on ethanol production.
Abstract: The need of Bioethanol or biofuel is increasing worldwide day by day due to renewable resources and ease of production form cheap raw materials. There are several factors that affect on bioethanol production by using yeast. The main objective of this research work was to isolate stress tolerant yeast from agro industry and optimize a process for et...
Show More
-
Temperature Dependence on the Photovoltaic Properties of Selected Thin-Film Modules
Issue:
Volume 2, Issue 4, July 2013
Pages:
140-146
Received:
30 May 2013
Published:
10 July 2013
Abstract: An important requirement in the employment of the different existing PV technologies is the understanding of the performance exhibited by each technology, once installed outdoors. Such records are necessary since the outdoor PV electrical characteristics are different from those corresponding to STC (which rarely occurs outdoors) information listed in manufacturer data-sheets. Therefore the PV monitoring and evaluations, under different environmental conditions, are indispensable for the architects and PV systems installers, in order to accurately size the installations. In this paper the influence of temperature on the photovoltaic parameters of amorphous silicon (a-Si) and copper indium diselenide (CIS) thin film modules has been investigated, as well as the energy produced under actual operating conditions. The cur-rent-voltage characteristics and maximum power have been recorded at regular intervals, for one year in the Mediterranean climate city of Patras, Greece (latitude 380). Patras averages over 4.2 peak sun hours (PSH) per day and module working temperatures between 16 0C and 600C. Our results have shown that, the percentage reduction of the open circuit voltage with temperature increase is greater for the CIS than for the a-Si modules. The short circuit current temperature coefficient for the CIS modules is positive at low and medium temperatures, though over the entire range of working temperature remains approximately constant with a slight tendency to reduce. The maximum power decreases almost linearly, while the efficiency for temperatures higher than 50oC reduces sharply. It is remarkable that with respect to the temperature increase the a-Si modules efficiency remains very near to the rated value, and the short circuit current temperature coefficient and the power coefficient are positive. The fill factor for these modules decreases linearly and equally as a function of temperature. The series and parallel resistance for the a-Si decrease slightly with temperature increase, whereas for the CIS the series resistance increases and the parallel resistance decreases in a more pronounced way. Maximum year-round energy production corresponds to the tilt angles of about 20 and 50 degrees in the summer and winter respectively.
Abstract: An important requirement in the employment of the different existing PV technologies is the understanding of the performance exhibited by each technology, once installed outdoors. Such records are necessary since the outdoor PV electrical characteristics are different from those corresponding to STC (which rarely occurs outdoors) information listed...
Show More
-
Study of Biodigester Design for Fuel and Fertilizer
Omprakash Sahu,
Yasabie Abatneh
Issue:
Volume 2, Issue 4, July 2013
Pages:
147-152
Received:
13 May 2013
Published:
10 July 2013
Abstract: Design of a biogas plant supplying energy for the students’ cafeteria while utilizing the abundant human waste has been done with an aim of significantly reducing wood consumption. Major fuels used in the cafeteria to prepare three meals per day for 3500 student’s electricity, Naphtha, and fuel wood. Three years data have been examined to study the pattern of the energy demand, amounts, and price of the energy sources with emphasis on wood. Feed stock potentials, its compositions, nearness to the cafeteria, and various other criteria have been considered in the site selection. It has been found that technically possible to produce as much as 30 cu/m/day biogas in the selected site contributing to 44.5% reduction in wood consumption. Performance of digesters in the climate and weather condition of the region for similar feedstock has been assessed to determine the appropriate digester model. Chinese fixed dome and Deenbandhu models are common and have shown good performance. Detail design and dimensioning of the digester have been done. Financial feasibility has been evaluated using NPV (net present value), internal rate of return (IRR) and simple payback method. Positive NPV, 18.5% IRR and a payback period of 6.27 years have been calculated indicating the financial feasibility.
Abstract: Design of a biogas plant supplying energy for the students’ cafeteria while utilizing the abundant human waste has been done with an aim of significantly reducing wood consumption. Major fuels used in the cafeteria to prepare three meals per day for 3500 student’s electricity, Naphtha, and fuel wood. Three years data have been examined to study the...
Show More
-
A Self Sufficient Energy Model for Poultry Farms in Bangladesh to Reduce Greenhouse Gas Emission and Increase Energy Efficiency
Mohammad Shariful Islam,
Asif Islam,
Enamul Basher
Issue:
Volume 2, Issue 4, July 2013
Pages:
153-162
Received:
24 June 2013
Published:
10 August 2013
Abstract: There are over two hundred thousand of poultry farms in Bangladesh. With the annual growth rate of twenty five percent, the number is increasing rapidly. Most of these poultry farms draw their required electricity from the national grid; few of them use natural gas or diesel generators as the sources of energy. Very small numbers of them use poultry droppings for producing biogas to generate electricity and for cooking. But these biogas plants barely run at the peak of their capacity. The over reliance on national grid and fossil fuels aids to the emission of greenhouse gases and it is going to spiral up every year. But the poultry farms can produce their own energy from the poultry droppings which will reduce annual costs, greenhouse gas emission and they can even produce fertilizer from the biogas plant which will add to the generated revenue. The aim of this study is to divulge the possibility of self sufficient poultry farms using their poultry droppings only. A comparison is made among the annual costs, energy efficiency and greenhouse gases emissions from different sources of energy or different mix of them. It has been found that co-production of electricity and fertilizer optimizes the mentioned constraints.
Abstract: There are over two hundred thousand of poultry farms in Bangladesh. With the annual growth rate of twenty five percent, the number is increasing rapidly. Most of these poultry farms draw their required electricity from the national grid; few of them use natural gas or diesel generators as the sources of energy. Very small numbers of them use poultr...
Show More
-
Tidal and Wind Energy Conversion Duo
Issue:
Volume 2, Issue 4, July 2013
Pages:
163-166
Received:
18 July 2013
Published:
10 August 2013
Abstract: The idea that is being explained in the paper is to harness tidal energy and to convert it into electrical energy. The idea is simple but is implemented in a very unique way. The prime mover that is installed is a wind turbine. The atmospheric air will be used to generate electricity but the driving factor which will act as an air pump is tides. It deals with required piping design and the specifications of components required to generate electricity. Here in this paper analysis has been carried out to explain and justify all the proposed aspects and also the advantages and shortcomings are listed.
Abstract: The idea that is being explained in the paper is to harness tidal energy and to convert it into electrical energy. The idea is simple but is implemented in a very unique way. The prime mover that is installed is a wind turbine. The atmospheric air will be used to generate electricity but the driving factor which will act as an air pump is tides. It...
Show More
-
Evaluation of Binders in the Production of Briquettes from Empty Fruit Bunches of Elais Guinensis
Kenechukwu Ugwu,
Kevin Agbo
Issue:
Volume 2, Issue 4, July 2013
Pages:
176-179
Received:
9 July 2013
Published:
10 August 2013
Abstract: Briquettes were produced from empty fruit bunches of oil palm plant using starch and asphalt separately as binders. The briquettes were compared based on their physical and chemical properties. The briquettes made with starch as binder had higher calorific value, higher burning rate and higher heat output. It also produced less smoke and ignited within a shorter time than the briquettes made with asphalt as binder. From the results, it will be easier to choose the binders for briquette making between asphalt and starch, though other parameters may be considered.
Abstract: Briquettes were produced from empty fruit bunches of oil palm plant using starch and asphalt separately as binders. The briquettes were compared based on their physical and chemical properties. The briquettes made with starch as binder had higher calorific value, higher burning rate and higher heat output. It also produced less smoke and ignited wi...
Show More
-
An Approach towards Sustainable Energy Performance by Green Building: A Review of Current Features, Benefits and Barriers
Molla Shahadat Hossain Lipu,
Taskin Jamal,
Tahia Fahrin Karim
Issue:
Volume 2, Issue 4, July 2013
Pages:
180-190
Received:
1 July 2013
Published:
20 August 2013
Abstract: Buildings are estimated to account for more than a third of the world’s resources in construction, 40 percent of global energy (including embodied energy), 12 percent of fresh water use, and generate 40 percent of greenhouse gases (GHGs) emissions and make up 40 percent of waste to landfill. The worldwide concerns for the impending resource crunch and the dangers of global warming, and the understanding of the role that buildings can play to contribute positively to the economy, energy security, human health and the environment have led to a quiet green building revolution around the globe over the last decade. Energy plays a vital role over the life cycle of a building, hence sustainable buildings and energy refurbishments in buildings hold enormous potential for energy saving and a reduction of greenhouse gas emissions. The main target of this paper is to find out the effectiveness and sustainability in green building design implementations which evaluates energy performances. In addition, the paper explains the key feature of the green building as well as its usefulness, current challenges and barriers.
Abstract: Buildings are estimated to account for more than a third of the world’s resources in construction, 40 percent of global energy (including embodied energy), 12 percent of fresh water use, and generate 40 percent of greenhouse gases (GHGs) emissions and make up 40 percent of waste to landfill. The worldwide concerns for the impending resource crunch ...
Show More