scholarly journals Parameter Biokinetika dari Degradasi Limbah Kol dan Tomat Menggunakan Sistem Bioreaktor Anaerobik

2021 ◽  
Vol 10 (2) ◽  
pp. 82-89
Author(s):  
Maya Sarah ◽  
Erni Misran ◽  
Seri Maulina ◽  
Ika Pertiwi ◽  
Nahlionny Ritman ◽  
...  

The world's energy supply is very dependent on non-renewable energy in the form of fossil fuels. This causes fossil fuels depletion and the need for alternative energy sources such as biogas. Biogas is produced from the fermentation process of organic matter with the help of anaerobic bacteria in free oxygen absence. This study aims to produce biogas from cabbage and tomato waste separately. Biogas production was carried out by varying feed concentrations of 100 g/L, 200 g/L, and 300 g/L for cabbage waste and 81.6 g/L; 215 g/L; and 237 g/L for tomato waste. This study consisted of 10 days seeding and acclimatization process, followed by a start-up stage using insulated anaerobic bioreactors. The largest methane from cabbage and tomato waste was 60% at a feed concentration of 200 g/L and 50% at a feed concentration of 237 g/L, respectively. The maximum growth rates (µm) for biogas from cabbage and tomato waste were 0.122 day-1 and 0.121 day-1, respectively.

Author(s):  
Kau-Fui Vincent Wong ◽  
Guillermo Amador

As society continues advancing into the future, more energy is required to supply the increasing population and energy demands. Unfortunately, traditional forms of energy production through the burning of carbon-based fuels are dumping harmful pollutants into the environment, resulting in detrimental, and possibly irreversible, effects on our planet. The burning of coal and fossil fuels provides energy at the least monetary cost for countries like the US, but the price being paid through their negative impact of our atmosphere is difficult to quantify. A rapid shift to clean, alternative energy sources is critical in order to reduce the amount of greenhouse gas emissions. For alternative energy sources to replace traditional energy sources that produce greenhouse gases, they must be capable of providing energy at equal or greater rates and efficiencies, while still functioning at competitive prices. The main factors hindering the pursuit of alternative sources are their high initial costs and, for some, intermittency. The creation of electrical energy from natural sources like wind, water, and solar is very desirable since it produces no greenhouse gases and makes use of renewable sources—unlike fossil fuels. However, the planning and technology required to tap into these sources and transfer energy at the rate and consistency needed to supply our society comes at a higher price than traditional methods. These high costs are a result of the large-scale implementation of the state-of-the-art technologies behind the devices required for energy cultivation and delivery from these unorthodox sources. On the other hand, as fossil fuel sources become scarcer, the rising fuel costs drive overall costs up and make traditional methods less cost effective. The growing scarcity of fossil fuels and resulting pollutants stimulate the necessity to transition away from traditional energy production methods. Currently, the most common alternative energy technologies are solar photovoltaics (PVs), concentrated solar power (CSP), wind, hydroelectric, geothermal, tidal, wave, and nuclear. Because of government intervention in countries like the US and the absence of the need to restructure the electricity transmission system (due to the similarity in geographical requirements and consistency in power outputs for nuclear and traditional plants), nuclear energy is the most cost competitive energy technology that does not produce greenhouse gases. Through the proper use of nuclear fission electricity at high efficiencies could be produced without polluting our atmosphere. However, the initial capital required to erect nuclear plants dictates a higher cost over traditional methods. Therefore, the government is providing help with the high initial costs through loan guarantees, in order to stimulate the growth of low-emission energy production. This paper analyzes the proposal for the use of nuclear power as an intermediate step before an eventual transition to greater dependence on energy from wind, water, and solar (WWS) sources. Complete dependence on WWS cannot be achieved in the near future, within 20 years, because of the unavoidable variability of these sources and the required overhaul of the electricity transmission system. Therefore, we look to nuclear power in the time being to help provide predictable power as a means to reduce carbon emissions, while the other technologies are refined and gradually implemented in order to meet energy demand on a consistent basis.


2021 ◽  
Author(s):  
Zeynu Shamil Awol ◽  
Rezika Tofike Abate

Abstract Biomass energy is renewable energy source that comes from the material of plants and animals. Forms of biomass energy are bio-ethanol, bio methanol, and biodiesel. Bio-ethanol is one of the most important alternative energy sources that substitute the fossil fuels. The focus of this research is to produce bio-ethanol from waste office paper. Five laboratory experiments were conducted to produce bio-ethanol from wastepaper. The wastepaper was dried in oven and cut in to pieces. Then it passed through dilute acid hydrolysis, fermentation and distillation process respectively. High amount of ethanol was observed at 20 ml/g (liquid to solid ratio) and at the time of 2hr. Cost and economic analysis for ethanol production from wastepaper was performed. Results from the analysis indicated a paper to ethanol plant was feasible from the economic point of view with rate of return (RR) 38.61% and the payback period of 2.2 years.


2016 ◽  
Vol 19 (3) ◽  
pp. 96-109
Author(s):  
Phung Thi Kim Le ◽  
Viet Tan Tran ◽  
Thien Luu Minh Nguyen ◽  
Viet Vuong Pham ◽  
Truc Thanh Nguyen ◽  
...  

Finding alternative energy sources for fossil fuels was a global matter of concern, especially in developing countries. Rice husk, an abundant biomass in Viet Nam, was used to partially replace fossil fuels by gasification process. The study was conducted on the pilot plant fixed bed up-draft gasifier with two kind of gasification agents, pure air and air-steam mixture. Mathematical modeling and computer simulations were also used to describe and optimize the gasification processes. Mathematical modeling was based on Computational Fluid Dynamics method and simulation was carried by using Ansys Fluent software. Changes in outlet composition of syngas components (CO, CO2, CH4, H2O, H2) and temperature of process, in relation with ratio of steam in gasification agents, were presented. Obtained results indicated concentration of CH4, H2 in outlet was increased significantly when using air-steam gasification agents than pure air. The discrepancies among the gasification agents were determined to improve the actual process.


2018 ◽  
Vol 182 ◽  
pp. 01018
Author(s):  
Sławomir Wierzbicki ◽  
Michał Śmieja

The limited resources of fossil fuels, as well as the search for a reduction in emissions of carbon dioxide and other toxic compounds to the atmosphere have prompted the search for new, alternative energy sources. One of the potential fuels which may be widely used in the future as a fuel is biogas which can be obtained from various types of raw materials. The article presents selected results as regards the effects of the proportion of biogas of various compositions on the course of combustion in a dual-fuel diesel engine with a Common Rail fuel system. The presented study results indicate the possibility for the use of fuels of this type in diesel engines; although changes are necessary in the manner of controlling liquid fuel injection.


2017 ◽  
Vol 22 (4) ◽  
pp. 805-836 ◽  
Author(s):  
Gerard van der Meijden ◽  
Sjak Smulders

The energy transition from fossil fuels to alternative energy sources has important consequences for technological change and resource extraction. We examine these consequences by incorporating a nonrenewable resource and an alternative energy source in a market economy model of endogenous growth through expanding varieties. During the energy transition, technological progress is nonmonotonic over time: It declines initially, starts increasing when the economy approaches the regime shift, and jumps down once the resource stock is exhausted. A moment of peak-oil does no longer necessarily occur, and simultaneous use of the resource and the alternative energy source will take place if the return to innovation becomes too low. Subsidies to research and development (R&D) and to renewables production speed up the energy transition, whereas a tax on fossil fuels postpones the switch to renewable energy.


Author(s):  
Jude Iyinbor ◽  
Ogunrinde Abayomi

Negative environmental effects, diminishing fossil fuel sources and soaring oil prices are some of the pertinent factors militating against the long term usage of fossil fuels. These make the introduction of alternative energy sources an integral part of our global energy plan. On the contrary, established fossil fuel infrastructures, flexibility of fossil fuels and economic gains from the oil sector are a few reasons why there is a global attitude of ‘drill the last drop before developing sustainable alternatives’. There are various energy sources that have little environmental effects and are sustainable (e.g. wind, geothermal, solar, hydro, biomass, e.t.c.), but the potentials they do have when it comes to the major energy utilization forms (heat, electricity and liquid and gaseous fuels) will be a key determinant of how alternative energy sources will be able to match the seemingly invincible presence of fossil fuels. The biomass option is examined in this report considering its potential with respect to heat, electricity and liquid and gaseous fuels market. Factors that may favour or hinder its potential and suitable solutions on how the potential can be increased are also discussed.


2017 ◽  
Vol 8 (2) ◽  
pp. 47
Author(s):  
Kris Hariyanto ◽  
Benedictus Mardwianta

Biogas is an alternative energy sources as a substitute for fossil fuels in household activities daily, but there are obstacles in the use of biogas, namely the difficulty of arranging a flame that is stable and fuel consumption relatively less efficient biogas. So it takes a design development system that will produce a burning stove produces biogas-fueled stove fits the purpose of research, on the other hand biogas stove should be simple, cheap production price, maximum efficiency and safe to use. Stages in the study include: desk assessment, creation of objective requirements design, manufacture conceptual and basic design, manufacture real stove. As for knowing the performance of the stove carried stove performance tests are: test flame stability and efficiency. The results showed that the efficiency of the biogas stove design results in only 31 percent higher than the efficiency of biogas stoves old design, while the fuel consumption of biogas stoves new design is 16 percent lower when compared with fuel consumption of biogas stoves old design. In terms of manufacture and ease of repair and maintenance of gas cookers new design is more easily repaired and easy to make and simple in form compared with the old design biogas stoves.


2020 ◽  
Vol 181 ◽  
pp. 01006
Author(s):  
Ambar Pertiwiningrum ◽  
Ratih Kusuma Wardani ◽  
Joko Wintoko ◽  
Rachmawan Budiarto ◽  
Margaretha Arnita Wuri ◽  
...  

The energy needs in Indonesia are mainly fulfilled by fossil fuels based energy. Since there is the rise of fuel price, Indonesia government considers seeking alternative energies from renewable resources. Biogas becomes one of the alternative energy that supplies energy needs and manages cow manure waste in Indonesia. To increase adoption of biogas technology, biogas production through methane enrichment is required. The experiment was conducted with return sludge system. These instruments consist of a series portable bio-digester, gas holder and return sludge unit. There were three treatments on biogas production without and with sludge addition or re-use bio-digester sludge that produced after biogas production as raw material for next biogas production. Biogas that produced was observed every two days during 40 days. The results showed that the addition of bio-digester sludge increased biogas production and methane concentration. The optimum retention time of biogas production with sludge addition was 20 days with accumulation biogas volume of 156.38 liters or increased of 38.75 from biogas production without bio-digester sludge). The optimum retention time to increase methane level was 15 days with methane enrichment from 0.8% to 29.41%.


2021 ◽  
Vol 311 ◽  
pp. 05003
Author(s):  
Yulia Anatolyevna Antokhina ◽  
Galina Yuryevna Peshkova ◽  
Elena Grigoryevna Bondar

The authors analyzed the current situation related to the global consumption of fossil fuels, as well as environmental problems caused by their extraction, production and consumption. The official statistical data were used, reflecting the volumes of export of fossil raw materials from the Russian Federation, the directions of raw materials flows, characterizing the demand for oil, gas, peat coal in international trade. The authors note that negative factors caused by currency fluctuations, pandemic and other factors did not lead to global changes in the fossil fuel market. The article presents the provisions of international documents adopted in order to prevent climate warming by reducing greenhouse gas emissions. In addition, attention is focused on distribution of responsibility between the developed and developing countries of the world. The authors analyzed the measures implemented in the territory of the Russian Federation, and identified positive trends to reduce emissions of pollutants into the atmosphere. Wherein, the article reflects the environmental risks associated with use of alternative energy sources and nuclear facilities, the assessment of which must be carried out during commissioning the corresponding facilities.


2013 ◽  
pp. 261-278
Author(s):  
Abdeen Mustafa Omer

In the recent attempts to stimulate alternative energy sources for heating and cooling of buildings, emphasis has been put on utilisation of the ambient energy from ground source 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. This paper highlights the potential energy saving that could be achieved through use of ground energy source. It also focuses on the optimisation and improvement of the operation conditions of the heat cycles and performances of the DX GSHP. It is concluded that the direct expansion of GSHP are extendable to more comprehensive applications combined with the ground heat exchanger in foundation piles and the seasonal thermal energy storage from solar thermal collectors. This article discusses the principle of the ground source energy, varieties of GSHPs, and various developments.


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