Integrated methods to improve efficiency of furnace burning recovered tail gas

Replacing nature gas (NG) by recovered hydrogen-rich tail gas to fuel a full-scale furnace has been proved to improve furnace efficiency and reduce NO_x formation. Adjusting residual O₂ concentration in flue gases, air preheat temperature and furnace damper angle will further improve the efficiency of the furnace burning the recovered hydrogen-rich tail gas. Prolonging the residence time of the hot gas flow increases the heat release time and reduces the time for the fuel to reach burning temperature so that the furnace efficiency can be improved. On-site test results using a full-scale furnace show that reducing the residual O₂ concentration in flue gases from 4.0 to 3.0 vol.% raises the furnace efficiency by 0.6%. Raising the pre-heated incoming air temperature from 200 °C to 240 °C and reducing furnace damper opening angle from 45° to 39° save 2.4 × 10⁶ and 1.9 × 10⁶ m³ of natural gas, respectively. Integrating the adjustment of flue gas residual O₂ concentration, temperature of incoming air temperature, and furnace damper opening angle will assist industries in achieving higher overall furnace efficiency and reducing carbon dioxide emission.     

Reduction of energy cost and CO2 emission for the furnace using energy recovered from waste tail-gas

In this research, the waste tail gas emitted from petrochemical processes, e.g. catalytic reforming unit, catalytic cracking unit and residue desulfurization unit, was recovered and reused as a replacement of natural gas (NG). On-site experimental results show that both the flame length and orange-yellowish brightness decrease with more proportion of waste gas fuel added to the natural gas, and that the adiabatic temperature of the mixed fuel is greater than 1800 °C. A complete replacement of natural gas by the recovered waste gas fuel will save 5.8 × 10⁶ m³ of natural gas consumption, and 3.5 × 10⁴ tons of CO₂ emission annually. In addition, the reduction of residual O₂ concentration in flue gases from 4% to 3% will save 1.1 × 10⁶ m³ of natural gas consumption, reduce 43.0% of NO_x emission, and 1.3 × 10³ tons of CO₂ emission annually. Thus, from the viewpoint of the overall economics and sustainable energy policy, recovering the waste tail gas energy as an independent fuel source to replace natural gas is of great importance for saving energy, reducing CO₂ emission reduction, and lowering environmental impact.     

Disaggregate energy consumption and industrial production in South Africa

This paper tries to assess the relationship between disaggregate energy consumption and industrial output in South Africa by undertaking a cointegration analysis using annual data from 1980 to 2005. We also investigate the causal relationships between the various disaggregate forms of energy consumption and industrial production. Our results imply that industrial production and employment are long-run forcing variables for electricity consumption. Applying the [Toda, H.Y., Yamamoto, T., 1995. Statistical inference in vector autoregressions with possibly integrated processes. Journal of Econometrics 66, 225–250] technique to Granger-causality, we find bi-directional causality between oil consumption and industrial production. For the other forms of energy consumption, there is evidence in support of the energy neutrality hypothesis. There is also evidence of causality between employment and electricity consumption as well as coal consumption causing employment.     

Development of method for estimation of world industrial energy consumption and its application

The energy balances published by the International Energy Agency (IEA) are one of the most valuable sources of energy statistics covering world energy supply and demand. However, some issues arise when these data are analyzed or used directly. Even when industrial energy consumption alone is examined, at least three types of issues are encountered: missing data, large amounts of misallocated data in some countries, and numerous unrealistic outliers in the time-series variations. When we deal with only a few regions, we can look at data one by one and modify them. In this case, we are going to overcome these issues with a systematic method because the data covers world including more than a hundred regions.This paper proposes a data reconciliation method to treat these issues, and describes its application to world industrial energy consumption. As a result of its application, we found that the three issues mentioned above seemed to be overcome. The degree of the reconciliation by region showed that OECD countries' degree tends to be smaller than those of non-OECD countries. However, not all of the OECD countries have low values and some countries, such as the United States, have high values.     

An energy development strategy for the USSR Minimizing greenhouse gas emissions

The second largest national consumer of commercial energy in the world, the USSR also emits large quantities of energy-related CO₂. This study uses four long-term scenarios of energy use and related emissions to investigate opportunities for reducing the USSR's greenhouse gas emissions over the next 30 years. This paper shows that if no measures are taken to control these emissions, CO₂ and methane will increase by 1.5 to 2 times the 1990 level by the year 2020. However, this growth can be restrained dramatically through structural changes in the Soviet economy, improved energy efficiency and interfuel substitutions. Abating emissions of carbon in the USSR would entail the widespread implementation of energy policies and, for more substantial reductions, higher investments from the Soviet economy. Achieving these goals would also require broad support from the international community.     

Future energy consumption and greenhouse gas emissions in Jordanian industries

Most, i.e. 85%, of greenhouse gas (GHG) emissions in Jordan emanate as a result of fossil fuel combustion. The industrial sector consumed 23.3% of the total national fuel consumption for heat and electric-power generation in 1999. The CO₂ emissions from energy use in manufacturing processes represent 12.1% of the total national CO₂ emissions. Carbon dioxide is also released as a result of the calcining of carbonates during the manufacture of cement and iron. Electricity, which is the most expensive form of energy, in 1999 represented 45% of total fuel used for heat and power nationally. Heavy fuel oil and diesel oil represented 46% and 7%, respectively, of all energy used by industry. Scenarios for future energy-demands and the emissions of gaseous pollutants, including GHGs, have been predicted for the industrial sector. For these, the development of a baseline scenario relied on historical data concerning consumption, major industries’ outputs, as well as upon pertinent published governmental policies and plans. Possible mitigation options that could lead to a reduction in GHG emissions are assessed, with the aim of achieving a 10% reduction by 2010, compared with the baseline scenario. Many viable CO₂ emission mitigation measures have been identified for the industrial sector, and some of these can be considered as attractive opportunities due to the low financial investments required and short pay back periods. These mitigation options have been selected on the basis of low GHG emission rates and expert judgement as to their viability for wide-scale implementation and economic benefits. The predictions show that the use of more efficient lighting and motors, advanced energy systems and more effective boilers and furnaces will result in a significant reduction in the rates of GHG emissions at an initial cost of between 30 and 90 US$ t⁻¹ of CO₂ release avoided. However, most of these measures have a negative cost per ton of CO₂ reduced, indicating short pay-back periods for the capital investments needed.     

Reduction of greenhouse gas emission on a medium-pressure boiler using hydrogen-rich fuel control

The increasing emission of greenhouse gases from the combustion of fossil fuel is believed to be responsible for global warming. A study was carried out to probe the influence of replacing fuel gas with hydrogen-rich refinery gas (R.G.) on the reduction of gas emission (CO₂ and NO_x) and energy saving. Test results show that the emission of CO₂ can be reduced by 16.4% annually (or 21,500 tons per year). The NO_x emission can be 8.2% lower, or 75 tons less per year. Furthermore, the use of refinery gas leads to a saving of NT$57 million (approximately US$1.73 million) on fuel costs each year. There are no CO₂, CO, SO_x, unburned hydrocarbon, or particles generated from the combustion of added hydrogen. The hydrogen content in R.G. employed in this study was between 50 and 80 mol%, so the C/H ratio of the feeding fuel was reduced. Therefore, the use of hydrogen-rich fuel has practical benefits for both energy saving and the reduction of greenhouse gas emission.     

Reduction potentials of energy demand and GHG emissions in China's road transport sector

Rapid growth of road vehicles, private vehicles in particular, has resulted in continuing growth in China's oil demand and imports, which has been widely accepted as a major factor effecting future oil availability and prices, and a major contributor to China's GHG emission increase. This paper is intended to analyze the future trends of energy demand and GHG emissions in China's road transport sector and to assess the effectiveness of possible reduction measures. A detailed model has been developed to derive a reliable historical trend of energy demand and GHG emissions in China's road transport sector between 2000 and 2005 and to project future trends. Two scenarios have been designed to describe the future strategies relating to the development of China's road transport sector. The ‘Business as Usual’ scenario is used as a baseline reference scenario, in which the government is assumed to do nothing to influence the long-term trends of road transport energy demand. The ‘Best Case’ scenario is considered to be the most optimized case where a series of available reduction measures such as private vehicle control, fuel economy regulation, promoting diesel and gas vehicles, fuel tax and biofuel promotion, are assumed to be implemented. Energy demand and GHG emissions in China's road transport sector up to 2030 are estimated in these two scenarios. The total reduction potentials in the ‘Best Case’ scenario and the relative reduction potentials of each measure have been estimated.     

Life-cycle energy consumption and greenhouse gas emissions for electricity generation and supply in China

The Well-to-Meter (WTM) analysis module in the Tsinghua-CA3EM model has been used to examine the primary fossil energy consumption (PFEC) and greenhouse gas (GHG) emissions for electricity generation and supply in China. The results show that (1) the WTM PFEC and GHG emission intensities for the 2007 Chinese electricity mix are 3.247 MJ/MJ and 297.688 g carbon dioxide of equivalent (gCO_2,e)/MJ, respectively; (2) power generation is the main contributing sub-stage; (3) the coal-power pathway is the only major contributor of PFEC (96.23%) and GHG emissions (97.08%) in the 2007 mix; and (4) GHG emissions intensity in 2020 will be reduced to 220.470 gCO_2,e/MJ with the development of nuclear and renewable energy and to 169.014 gCO_2,e/MJ if carbon dioxide capture and storage (CCS) technology is employed. It is concluded that (1) the current high levels of PFEC and GHG emission for electricity in China are largely due to the dominant role of coal in the power-generation sector and the relatively low efficiencies during all the sub-stages from resource extraction to final energy consumption and (2) the development of nuclear and renewable energy as well as low carbon technologies such as CCS can significantly reduce GHG emissions from electricity.     

Reduce energy use and greenhouse gas emissions from global dairy processing facilities

Global butter, concentrated milk, and milk powder products use approximately 15% of annual raw milk production. Similar to cheese and fluid milk, dairy processing of these products can be energy intensive. In this paper, we analyzed production and energy data compiled through extensive literature reviews on butter, concentrated milk, milk and whey powder processing across various countries and plants. Magnitudes of national final and primary specific energy consumption (SEC) exhibited large variations across dairy products; in addition, the final SEC of individual plants and products exhibited significant variations within a country and between countries. Furthermore, we quantified national energy intensity indicators (EIIs) accounting for dairy product mixes and technological advancement. The significant variations of SEC and EII values indicate a high degree of likelihood that there is significant potential for energy savings in the global dairy processing industry. Based upon the study samples, we estimate potential energy savings for dairy processing industry in selected countries, and estimates annual reduction of 9–14 million metric-ton carbon-equivalent¹ could be achieved if measures are implemented to lower SEC values by 50–80% in half of global dairy plants. The paper calls for publication of more energy data from the dairy processing industry.     

Reduction of energy consumption in biodiesel fuel life cycle

Essential requirements for biofuel are that (a) it should be produced from renewable raw material, and (b) it should have a lower negative environmental impact than that of fossil fuels. Apart from direct assessment of the engine emissions, environmental impact is also determined by performing life cycle analysis. Life cycle energy balance depends on specific climatic conditions and the agro- and processing technologies used. Rapeseed oil methyl ester life cycle energy ratios in Lithuanian conditions have been calculated as a function of rapeseed productivity, oil pressing and transesterification technologies used.Opportunities to improve biodiesel fuel life cycle energy efficiency, by implementing new technologies in agriculture as well as in industrial processing, were reviewed. The effectiveness of new technologies was evaluated on the basis of energy balance comparison.     

Profiting from negawatts: Reducing absolute consumption and emissions through a performance-based energy economy

Current energy and GHG emissions policies either focus directly on emissions or promote renewable production and the implementation of specific efficiency measures. Meanwhile, the fundamental structure of the energy market based on profits through energy throughput remains largely unchallenged. This policy oversight prevents the transition to an energy economy in which profits are based on energy services delivered at the lowest energy cost: a performance-based energy economy (PBEE). The PBEE applies the combined concepts of the performance economy and energy services to the energy sector. Energy Service Companies (ESCOs) are discussed as an example of PBEE practices. The implications for energy suppliers and consumers as well as the conditions for PBEE diffusion and consequences for technological change are also explored. The expected environmental, social and economic benefits are described. However, absolute consumption and emissions reductions may prove elusive due to the rebound effect. In order to forestall rebound-led increases, complementary policy measures likely to lead to absolute reductions are required.     

Prospects of India's energy and emissions for a long time frame

For any nation, sector-wise forecasts of energy demand and emissions are becoming valuable elements in devising its national and international policies relating to energy security, local environment, and global climate change. It is in this context that this work attempts to forecast India's possible energy demands and emissions adopting a key indicator approach on least cost generation expansion optimization methodology for a long time frame. This study developed key indicators for useful-energy demand for end-use sectors such as industry, commerce, and residence. Key indicators for transport sector and non-energy use sectors were developed on transport mobility demand and end-use fuel demand. The main drivers of these key indicators are socio-economic parameters. This work was conducted in a linear programmed (LP) TIMES G5 model on TIMES modeling framework for model horizon of 1990–2100. By the end of the 21st-century, India's energy demands are projected to be about 1825 Mtoe of primary energy, 1263 Mtoe of final energy consumption, 4840 TWh of electricity generations, 723 Mtoe of energy import, and 4414 Mt of CO₂ emissions.     

Analysis of scenarios for the reduction of energy consumption and GHG emissions in transport in the Basque Country

Fossil energy depletion and fight against climate change force humanity to decarbonize the economy. By year 2050 CO₂ emissions will have to reduce globally at least 85%, and probably over 95% in developed countries.The modeling of the transportation of people and commodities in the Basque Autonomous Community (Spain) in year 2008 has allowed us to draw some conclusions about the challenges ahead. The exploration of several scenarios modeled in order to reduce energy consumption in transport shows that mobility in a decarbonized world will have to be more efficient, electrified when moving people and freight on land, based on renewable generation, and organized in such a way that guarantees very high occupancies of vehicles. All these elements will be indispensable, and even not sufficient if they are still not complemented with a reduction of mobility in absolute terms, so that economic transportation intensity—the ratio between transportation and whole economic activity—recovers to levels seen in the world four decades ago, prior to the development of present hypermobility.     

Effect of refuse-gas fuel use on energy consumption in an industrial pusher furnace

To save natural gas (NG) in heating steel slabs, a heat-recovery device (HRD) is used in a metallurgical pusher furnace together with refuse blast-furnace gas (RBFG) and O₂. These NG-saving techniques are evaluated by using finite-time thermodynamics. The results indicate that mixing a higher percentage of RBFG with NG does not necessarily save NG. However, a higher percentage of O₂ in air and a larger HRD do save NG.     

Steam gasification of energy crops of high cultivation potential in Poland to hydrogen-rich gas

In the paper energy crops of considerable cultivation potential in Poland, namely: Salix viminalis, Helianthus tuberosus, Sida hermaphrodita, Spartina pectinata, Andropogon gerardi and Miscanthus X giganteus were tested in terms of steam gasification reactivity of biomass chars, as well as yields and composition of product gas in steam gasification and lime-enhanced steam gasification in a laboratory scale fixed bed reactor at 650 °, 700 ° and 800 °C.The highest value of reactivity for 50% of carbon conversion, R₅₀, was observed for Sida hermaphrodita, regardless the process temperature.Application of CaO for in-situ CO₂ capture in steam gasification of biomass chars resulted in hydrogen content increase at 650 °C to the levels comparable with the ones reached at 800 °C without carbonation reaction. Also hydrogen and total gas yields increased in tests of lime-enhanced gasification.     

Indicators for industrial energy efficiency in India

India accounts for 4.5% of industrial energy use worldwide. This share is projected to increase as the economy expands rapidly. The level of industrial energy efficiency in India varies widely. Certain sectors, such as cement, are relatively efficient, while others, such as pulp and paper, are relatively inefficient. Future energy efficiency efforts should focus on direct reduced iron, pulp and paper and small-scale cement kilns because the potentials for improvement are important in both percentage and absolute terms. Under business as usual, industrial energy use is projected to rise faster than total final energy use. A strong focus on energy efficiency can reduce this growth, but CO₂ emissions will still rise substantially. If more substantial CO₂ emissions reductions are to be achieved then energy efficiency will need to be combined with measures that reduce the carbon intensity of the industrial fuel mix.     

Analysis and forecast of the Tianjin industrial carbon dioxide emissions resulted from energy consumption

This paper analyses the carbon dioxide emissions caused by industrial energy consumption of Tianjin from 2005 to 2012. The carbon emissions decomposition illustrated that the scale of production factor played a major role in the growth of Tianjin industrial carbon emissions and the average contribution of carbon emissions is up to 220.8975% in the statistical period; the intensity of energy factor played an important role in slowing down the growth of industrial carbon dioxide emissions. The average contribution of carbon emissions was ?136.1994% in the statistical period. The prediction model based on carbon emissions data from industrial energy consumption from 2003 to 2012 reached a high accuracy, with an average error of 1.78% for stochastic impacts by regression on population, affluence, and technology (STIRPAT) model, 2.41% for the Logistic regression model and an average error of 1.54% for the grey model. This research can contribute to predict the carbon emission and through it some suggestions can be made.     

CO2 emissions,energy consumption,and output in France

This paper examines the dynamic causal relationships between pollutant emissions, energy consumption, and output for France using cointegration and vector error-correction modelling techniques. We argue that these variables are strongly inter-related and therefore their relationship must be examined using an integrated framework. The results provide evidence for the existence of a fairly robust long-run relationship between these variables for the period 1960–2000. The causality results support the argument that economic growth exerts a causal influence on growth of energy use and growth of pollution in the long run. The results also point to a uni-directional causality running from growth of energy use to output growth in the short run.     

Life cycle analysis of energy use and greenhouse gas emissions for road transportation fuels in China

Life cycle analysis is considered to be a valuable tool for decision making towards sustainability. Life cycle energy and environmental impact analysis for conventional transportation fuels and alternatives such as biofuels has become an active domain of research in recent years. The present study attempts to identify the most reliable results to date and possible ranges of life cycle fossil fuel use, petroleum use and greenhouse gas emissions for various road transportation fuels in China through a comprehensive review of recently published life cycle studies and review articles. Fuels reviewed include conventional gasoline, conventional diesel, liquefied petroleum gas, compressed natural gas, wheat-derived ethanol, corn-derived ethanol, cassava-derived ethanol, sugarcane-derived ethanol, rapeseed-derived biodiesel and soybean-derived biodiesel. Recommendations for future work are also discussed.