International Journal of Global Warming (38 papers in press)
Sedge for biogas production and improving the process by
pretreating sedge prior to co-digestion
by Nusara Sinbuathong, Netechanok Sombat, Wannapa Kratay
Abstract: Sedge is an indigenous weed and produces a large amount of biomass. Co-digestion of the feedstock of sedge:cow dung:water at the ratio of 10:10:80 was investigated. The mixture of the untreated sedge and that of the pretreated sedge (with 1% sodium hydroxide for 24 hr) with cow dung were the feedstock in this study. The two reactors were supplied with feedstock of untreated and pretreated sedge with cow dung separately in a semi-continuous-flow mode with a hydraulic retention time of 40 days. The methane yield of co-digestion of the pretreated sedge reached 344 L at STP/kg chemical oxygen demand degraded and was 10.97 % greater than that of the untreated sedge or 169 L at STP/kg total solids added and was 26.12 % greater than that of the untreated sedge. The alkali pretreatment of sedge prior to co-digestion with cow dung improved the process of biogas production notably.
Keywords: anaerobic digestion; biogas; co-digestion; global warming; lignocellulosic biomass; methane; pretreatment; renewable energy; sedge.
ANALYSIS OF CARBON SEQUESTRATION BY DOMINANT TREES IN URBAN AREAS OF THANE CITY
by Aasawari Tak, Umesh Kakde
Abstract: The present investigation was conducted to estimate the total carbon sequestered by urban trees in Thane city (India). The total tree biomass, total stored carbon, and CO2 removed by urban trees was determined by with allometric model/volume equations and compared. Using random sampling plot method 50 plots with 0.04ha each, generated to facilitate measurements of trees. It was observed that, carbon sequestration (kgC/tree) was highest in Azadirachta indica, 3289.8 kgC/tree, followed by Ficus benghalensis (2375.5 kgC/tree), Tamarindius indica (1666.9 kgC/tree), Casurina equisetifolia (1530.5 kgC/tree) and Pongamia pinnata (865.9 kgC/tree). The investigation data will be helpful to evaluate the role of urban trees in reducing atmospheric the carbon dioxide. The study will also be useful in assessment of carbon storage potential of the several regions, which are under the threat of air pollution issues worldwide in near future.
Keywords: Allometric model; tree biomass; carbon sequestration; carbon storage; volume
The Assessment of Air Quality in the Port of Ambarli and Several Districts of Istanbul
by Kaan Ünlügençoglu, Fuat Alarçin
Abstract: Sea transportation is considered as an environmentally friendly transportation option compared to other freight transportation such as airway, rail and road transport. The majority of freight transportation is completed by the sea. Moreover, emissions from ships are increasing due to the increase in trade volume and sea transportation worldwide. Due to this increase, health of people living in coastal cities is affected adversely. In this study, real-time air quality measurements of PM2.5, PM10, SO2, CO, NO and NO2 emissions are performed for 3 months in the Port of Ambarli located in Marmara region that has intense sea trade. The daily average values of real-time emission data measurement are shown for June, July and August 2017. Real-time measurements are received from Air Quality Monitoring Station in Avcilar district of Istanbul for the same period and same air quality measurement device. These PM2.5, PM10, SO2, CO, NO and NO2 emission values are compared with the limit values of air quality in Europe and Turkey. As a result, PM2.5, PM10, SO2, CO, NO and NO2 measurements are under air quality limit value set by Europe and Turkey for the Port of Ambarli based on values obtained from Avcilar and Kadikoy.
Keywords: shipping emission; air quality; measurement; Port of Ambarli; EU Limits.
Methodological framework for adopting sustainable transport measures
by Maha Alsabbagh
Abstract: The term sustainable transport first appeared in the literature over two decades ago. An extensive literature has subsequently evolved, ranging from attempts to clarify the concept to explorations of its actual implementation worldwide. Yet, structured approaches for achieving sustainable transport in developing countries, where data are limited, remain rare. This paper, presents a pragmatic methodological framework for adopting sustainable transport measures related to passenger cars in Bahrain. The proposed assessment process comprises four steps: analyzing the current state, identifying potential measures, assessing these measures, and aggregating the results. The analysis revealed that while achieving sustainable transport in Bahrain is feasible using regulatory and economic measures, fiscal incentives to car technologies may be required to ensure public acceptance. While the focus of this paper is on Bahrain, the proposed methodology is readily applicable to other countries where data are limited.
Keywords: climate change; content analysis; cost-benefit analysis; DPSIR; energy modeling; multi-criteria analysis; passenger cars; probabilistic analysis; scenarios; stakeholder analysis; sustainability.
Multi-Perspective Influence Mechanism Analysis and Multi-Scenario Prediction of Chinas Carbon Emissions
by Tao Yi, Mohan Qiu, Hao Zheng, Jinpeng Liu
Abstract: Due to the mandatory push to meet the carbon emission reduction commitments proposed in the Paris Agreement, an analysis of the peak carbon emission production times in China is required. This paper focuses on the peak production times of the total carbon emissions (TCE) and carbon emissions intensity (CEI) in China. According to the development of China's carbon emissions and related targets in the 13th Five-Year Plan, the peak production times of TCE and CEI in different scenarios are predicted based on an influence mechanism analysis of China's carbon emissions from the perspectives of energy, economy, and society. Considering the development characteristics of China at this stage, this paper introduces several new indicators including the full-time equivalent of research and development (R&D) personnel and the investment in environmental pollution control. Based on the results of the study, several policy recommendations are put forward to fulfil Chinas carbon emission reduction commitments.
Keywords: carbon emissions; peaking time; influence mechanism; scenario prediction; Paris Agreement.
Social selection analysis for a role of nuclear power generation by evolutionary game theory (EGT) in the aspect of global warming assessment
by T.A.E. H.O. WOO
Abstract: The evolutionary game theory (EGT) is introduced for the simulations of the global warming incorporated with energy consumptions in which the life evolution is analyzed by the game theory for the energy sector selection. It is easy to see that each energy sector has the pros and cons as the environmental factor as well as economic factor. The fossil fuels such as oil or coal have severe pollutions to the atmosphere, although it is comparatively simple to make energy productions. There are the models of electricity generations as EGT and cumulating EGT. The highest values are 329.715 in 99th month and 2749.590 in 96th month for evolutionary and cumulating EGT, respectively. Comparing two graphs, the trends are similar to be stabilized in later time where the priority of nuclear energy as the aspect of the global warming factor increases to be paralleled.
Keywords: Nuclear; Global warming; Evolution; Game; Energy.
Assessment of thermo-economic performance based on heat recovery preference of air conditioning systems
by M.Ziya Sogut, Hamit Mutlu, T.Hikmet Karakoc
Abstract: Thermal comfort demand in modern buildings is provided by mostly usage central air conditioning and ventilation systems. In these applications, the comfort parameters of the structure are directly related to control of air velocity, blowing temperature, air quality and energy consumption. In these processes, reduction of energy consumption considering thermal comfort conditions and system management with energy efficiency in buildings should be evaluated together with the heat recovery potential in the air conditioning systems. In this study, the thermo-economic analyses of four different application including the heat recovery systems in the air conditioning systems, which was designed for an office building, were made. In these thermo-economic analyses, it is seen that up to 72% energy saving can be achieved with the heat recovery preference according to standard conditions. At the end of the study, system preference in a centralized air conditioning system based on air conditioning processes and its contribution to sustainable energy management were assessed
Keywords: Air conditioning Unit; Heat Recovery; Energy Management; Efficiency; Sustainability.
Hydrometeorological Trend Analysis using the MannKendall and Innovative?en Methodologies: A Case Study
by Dang Nguyen Dong Phuong, Vo Ngoc Quynh Tram, Tran Thong Nhat, Tran Dinh Ly, Nguyen Kim Loi
Abstract: This paper analyzed temporal trend possibilities of hydrometeorological records in Vu Gia Thu Bon watershed during 19792014 by employing the recently innovative?en trend methodology in combination with the classical/modified MannKendall tests. The outcomes show that most of statistically significant increasing trends were found in annual rainfall, extreme temperatures, relative humidity and stream flow, whereas opposite trend direction was predominantly observed in evapotranspiration and sunshine duration over the 36year period. Particularly, the greatest warming trends in maximum and minimum temperature were 0.019 and 0.024
Keywords: hydro–meteorological trend; Innovative–?en; Mann–Kendall test; sub–trend; Vu Gia Thu Bon watershed.
Progress on Carbon Dioxide Capture, Storage and Utilization
by Malek Mohammad, Rima J. Isaifan, Yemane Weldu, Mohammad Aziz Rahman, Sami G. Al-Ghamdi
Abstract: The negative impacts of global warming on climate have been witnessed worldwide, and therefore global efforts to decrease the emission of greenhouse gases (GHGs), particularly carbon dioxide, have increased. Carbon capture (CC) strategies can effectively reduce the quantity of CO2 being released into the atmosphere by various industries. In this study, several characteristics of CC technologies are analyzed, the negative environmental impacts of CO2 emissions are highlighted, policies that have recently been adopted to decrease GHG emissions are discussed, and state-of-the-art post-combustion CC, pre-combustion CC, and oxyfuel combustion CC technologies are reviewed. Furthermore, this study investigates and compares the three most common carbon separation techniques, namely, absorption, adsorption, and membrane methods. Through the investigation of the CC technologies, we discuss the practicality of implementing such methods and discuss specific case studies that have implemented CC technologies. Furthermore, we summarize ways of utilizing the end-product (the captured carbon) of these technologies. Much research has gone into investigating the negative environmental impacts that are currently arising. This paper stresses the importance of taken measures that go from theory to implementation and how such measures can be approached.
Keywords: Carbon dioxide; Carbon capture and storage (CCS); CO2 separation; CO2 utilization; Environmental impacts.
Probabilistic Innovative trend analysis (PITA)
by Zekâi ?en
Abstract: The impact of trend and variability embedded in the composition of hydro-meteorological time series records from past stationary character to present and future non-stationary forms must be identified in a refined manner for better engineering, social, economy and environmental mitigation, adaptation and management purposes. There are various methodologies from the most frequently used Mann-Kendal (MK) trend test, Sen slope method, regression approach to recently innovative trend analysis (ITA) methodologies, which are at the focus of recent trend assessment researches in applications, but all these methodologies do not take into consideration the underlying probability distribution function (PDF) of time series concerned. Apart from the ITA method others depend on restrictive assumptions such as the normal (Gaussian) PDF and independent serial correlation structure. Especially in the practical applications these two points are not cared for in applied research papers in the literature, and consequently their final conclusions are rather biased. This paper proposes another new innovative methodology, whereby not statistical parameters but actual PDFs play the major role. The methodology is named as the innovative probabilistic trend analysis (IPTA), which has the most convenient climate change basic definition without any restrictive assumption. Its application is presented to temperature, precipitation and river discharge data from different parts of world.
Keywords: climate change; climate variability ; innovation; probability; trend; time series.
The evidence of recent Canadian Arctic climate change: A case study, the Baffin Island
by Farahnaz Fazel-Rastgar
Abstract: The evidence of the climate change in Baffin Island, the largest island in Canadian Arctic, is examined by analyzing the meteorological datasets from NARR (The North American Regional Reanalysis Model) and NCEP (National Center for Atmospheric Research). The yearly mean time series data analysis (from 1948 to 2017) of the near-surface air temperatures, the vertical velocity at 700mb, precipitation rate and specific humidity show the rapid changes during recent decade over the Baffin Island region. The yearly mean of the near-surface air temperature has the highest value in 2010 corresponded to the lowest value of the North Atlantic Oscillation (NAO) index for the same year. This research also shows that the mean yearly vertical velocity at 700mb linearly decreases (at a significant level with a very small p-value of 0.000235) with the 1000mb air temperatures from 1948 to 2017 causing to increase the vertical motion (negative omega) and a possible increased the local instability over Baffin Island region. Monthly anomalies of the physical and meteorological data such as near-surface air temperature, surface albedo and the average precipitation on the surface are also investigated from 2007-2017. The results show that the region has been getting warmer over the past 10 years with the higher maximum values during January and February months (rather warmer winters). Also, the surface albedo has been decreased mostly in the coastal boundaries especially during October around 10-30%. This study also shows that the average precipitation at the surface also has been increased in some parts of Baffin Island with the remarkable changes during June, July, September and November mostly in the south part of the Baffin Island region. Whereas during the months of April and May (except over the topographical areas in the south-east with higher values) the precipitation has been decreased respect to climatology mean.
Keywords: Climate change; near surface air temperature; surface albedo; precipitation; specific humidity.
Energetic valorization of waste tires by pyrolysis: Catalyst effect on tires derived oil and gases
by Hiba REJEB, Emna BERRICH BETOUCHE, CHAHBANI Mohamed Hachemi, Fethi ALOUI
Abstract: Used tires wastes represent health, environmental and ecological problems because of their composition, storage and degradation difficulties. To solve this problem and to upgrade this waste, several technologies are adopted such as pyrolysis. This process allows the production of liquids which could replace fuels. In this paper an experimental investigation is carried out to study the effects of zeolite catalyst ZSM5 on pyrolysis Tires Derived Oil and gas. Two percentages of zeolite catalyst have been chosen i.e. 10% and 20%. Experiments were carried out in a semi-batch reactor under inert atmosphere. The Tires Derived Oil properties measured are the density, the viscosity, the higher calorific value and the acid value. It is found that the tires wastes pyrolysis without catalyst gives a Tires Derived Oil yield equal to 30.53 wt.%. This yield remains constant while using 20% of ZSM5. However, it increases to 32.77 wt.% while using 10% of the catalyst. The Tires Derived Oil obtained presents characteristics close to those of diesel and kerosene. For example, its viscosity is nearly 1 (cP) at 40
Keywords: Wastes; Energetic valorization; Pyrolysis; Catalyst; Fuel; Gas; Micro-gases Chromatography and Calorimetric analysis.
Investigation the insights between health expenditure and air quality
by ZEYNEP CEYLAN
Abstract: In this study, models have been developed for predicting health expenditures of Turkey associated with greenhouse gas (GHG) emission levels using 27-year dataset between the years 1990 and 2016. The annual GHG emissions data consisting of carbon dioxide, methane, nitrous oxide, and fluorinated gases have been used as inputs. In order to increase the accuracy and reliability, three different models namely, the Bayesian-optimization based support vector regression (BO-SVR), three-layered feed-forward back-propagation neural network (BPNN) and multivariate linear regression (MLR) models were employed. The coefficient determination (R2) for the BO-SVR, BPNN and MLR models were determined as 0.9893, 0.9796, 0.9766 in the training phase and 0.9795, 0.9629, and 0.9529 in the testing phase, respectively. The results showed that the BO-SVR model is found to be superior for the estimation of Turkeys health expenditures.
Keywords: GHG emissions; Bayesian optimization; SVR; health expenditure; forecasting; ANNs.
How to benefit from the food waste in the era of global warming
by S. Kaan Gökbulak, Serap Nazir, Mustafa Özilgen, Sena Tuncel
Abstract: Food wastes causes 4.4 GtCO2 eq, or about 8% of total anthropogenic GHG (greenhouse gas) emissions annually. Thermodynamic analyses showed that 1 t of FFRW (fast food restaurant waste), after pressing its water out and pre-drying, would be capable of producing approximately 3.5 GW electricity. There is a common belief among the chefs that finding a way for the consumption of the kitchen waste may reduce the environment burden. After testing this hypothesis with eighteen foods, it is concluded that although it would be possible to recover 7.2 GJ y-1 of energy in Turkey. This would be equivalent to that of electric power production with the FFRW in Rankine cycle in less than three seconds. Analyses indicated that electric power generation from the FFRW in a Rankine cycle would be feasible, and reduce its global warming potential, but trying to find a secondary use for the kitchen waste is not.
Keywords: Fast food restaurant waste; kitchen waste; energy and exergy savings; cumulative degree of perfection; global warming potential.
Environmental sensitivity of printed circuit board (PCB) manufacturing to Cu recycling rate, transportation and various energy sources
by Elif Ozkan, Bilge Bas, Nilay Elginoz, Fatos Germirli Babuna
Abstract: This study concentrates on environmental impacts of PCB manufacturing. The objective is to examine the effect of Cu recycling rate, transportation, energy sources and end-of-life (EoL) on global warming (GWP), marine aquatic ecotoxicity (MAEP), terrestric ecotoxicity (TETP), freshwater aquatic ecotoxicity (FAETP), human toxicity (HTP), ozone layer depletion (ODP), photochemical ozone creation (POCP), eutrophication (EP), acidification (AP) and abiotic depletion (ADP fossil, ADP elements) potentials. Increasing Cu recycling rate from 30% to 47%, reduce the impacts by 10 to 103%. The most significant reduction is for HTP. Transportation elevates AP and POCP by 29%, ADP fossil by 23% and GWP by 21%. Obtaining energy from renewable sources causes 56, 40 and 39% reductions in HTP, ADP fossil and GWP, namely. Apart from GWP where PCB manufacturing and EoL has equal impacts, for the other categories PCB manufacturing has more than 75% contribution.
Keywords: printed circuit board; life cycle assessment; manufacturing; electronics industry; Cu recycling; transportation; energy source.
Empirical models for estimating the daily and monthly global solar radiation for Mediterranean and Central Anatolia region of Turkey
by Ismail Ustun, Cuma Karakus, Huseyin Yagli
Abstract: Climatology and geoengineering studies in literature clearly identify the relationship between solar radiation and global warming. These studies generally try to predict progress in global warming. To do that, it is essential to predict solar radiation rate, which is directly proportional to global warming. By the obtained solar radiation models in present study, researcher will be adequate to estimate solar radiation rate accurately for future prediction analysis. In this study, data imported from measurement stations were used to develop and validate radiation models by using regression and multi-regression models to estimate daily and monthly global solar radiation for Urgup, Karaman, Nigde, Isparta, Iskenderun and Adana regions. The statistical parameters (MBE, MPE, RMSE and R2) carried out to evaluate the performance of obtained estimation models. In addition, climatic properties of selected regions had been deeply examined to analyse usability of obtained estimation model for other regions where have similar climate characteristics.
Keywords: Climate analyses; regression and multi-regression analyses; daily and monthly solar radiation; estimation models; solar radiation.
Carbon footprint as an environmental sustainability indicator for a higher education institution
by Ihsan Ullah, Islam Uddin, Uzma Naoreen, Majid Hussain
Abstract: This study aimed to quantify carbon footprint of the University of Haripur (UoH), Pakistan for one fiscal year (July 2016Jun 2017). Primary data was collected through questionnaire surveys, interviews, personal observations and measurements by visiting concerned offices, departments, laboratories, library, canteens, and agriculture fields. The UoH carbon footprint was calculated according to the IPCC 2007 greenhouse gas (GHG) protocol for 100 years time horizon using environmental impacts modelling software SimaPro v.8.4. The results showed that UoH emitted around 578,898 kg CO2-eq emissions to environment during 2016-2017. The largest GHG emission (38%) from single source to the total carbon footprint was from the purchased electricity. Up to our knowledge, there is no published literature available for any other Pakistani universities who conducted their carbon footprint.
Keywords: Higher Education Institution; Carbon footprint; Students; GHG emissions; UoH; Pakistan.
Effect of Addition CNTs in Passive Sampler for Ammonia Measurement in Outdoor Air
by Andac Akdemir
Abstract: It was determined that the adsorption capacity of nano materials was higher than that of conventional adsorbents. In this study based on this topic, It is aimed to improve the performance of classical passive samplers for measuring high concentration of ammonia. Ammonia was measured at 6 different points in the industrial zone. The CNT addition sampler was also used in the measurements together with the conventional ammonia passive sampler. Thus, the effect of CNT addition on ammonia concentration was investigated. It was observed that the low CNT addition correlated with the conventional passive sampler but the correlation was decreased in the addition of high CNT.
Keywords: MWCNT; Air Quality; Ammonia; Fertilizer production plant.
Research on food carbon emissions of consumers based on restaurant investigations in Shenyang, China
by Yue Wang, Ruxi Liu, Bo Wu, Nan Wang, Yang Liu
Abstract: China became has become the largest carbon emitter. This study aimed at examining The aim of this study was to examine the food greenhouse gas emissions emissions (GHGs) of consumers based on restaurant investigations in Shenyang, China. The food GHGs per capita per meal of consumers at restaurants in Shenyang were 4.07 times more than the national average in 2016. The percentage of meat GHGs was 77.06%. The food GHGs of consumers of medium-sized restaurants were the highest. The food GHGs of consumers of buffets were 1.5 times higher than those of consumers of table meals. The consumption of meat was 6.06 times than the upper limit of the recommended amount. The food GHGs per capita per meal of consumers at restaurants in Shenyang were markedly higher than the national average in 2016. The dietary patterns of eating out were unreasonable. Therefore, guidance must be provided for regarding the behaviorbehaviours of people who dine out and of restaurant owners.
Keywords: food; restaurant; greenhouse gas emissions (GHGs); dietary pattern.
Color and COD Removal from Aqueous Solutions of Direct Yellow 86 Textile Dyestuff by Electro-Fenton Method
by Nevzat BEYAZIT
Abstract: In this study, COD and color removal were investigated by the electro-Fenton method from aqueous solutions of direct Yellow 86 commercial textile dyes. The effects of electrolyte concentration (250-3000 mg/l), H2O2 concentration (250-3000 mg/l), initial dye concentration (50-500 mg/l), distance between anode and cathode (0.5-1.5 cm) on COD and colour removals were investigated. Under optimal experimental conditions (NaCl: 1500 mg/l, H2O2: 1500 mg/l, initial dye concentration: 50 mg/l, anode-cathode distance: 1.5 cm), the maximum COD and color removal efficiencies were 95.3% and 99.5%, respectively. It was determined that H2O2 concentration and dye concentration had the highest effect on removal efficiencies. It was determined that removal efficiencies increased with increasing H2O2 concentration, and decreased with increasing initial dye concentration. The results show that the electro-Fenton method can be effectively applied in COD and color removal from aqueous solutions of direct Yellow 86 commercial textile dyestuff.
Keywords: COD removal; color removal; direct yellow 86; electro-Fenton; removal efficiency.
Meteorological Analysis of a Fatal Istanbul Helicopter Accident on Mar 10, 2017
by Emrah Tuncay Özdemir, Oguzhan Kolay
Abstract: On Mar 10, 2017, a helicopter belonging to a private company departed Atat
Keywords: Istanbul Atatürk International Airport; Helicopter Accident; Stratus; Fog; Satellite Products.
Enviromental performance of the wastewater treatment plants: Green Index
by Pelin Yapicioglu, Özlem Demir
Abstract: The Green Index as a new indicator to determine the environmental performance has been developed in order to reduce the unfavorable environmental of the wastewater treatment plants. The main aim of this study is to reveal the environmental performances of the wastewater treatment plants. An industrial and a municipal wastewater treatment plant in Turkey have been compared in terms of the Green Index. The results revealed that in August, for the municipal and the industrial wastewater treatment plants, CO2 emission values were 0.972 and 0.42 kg/h, respectively. N2O emissions were also 8.7 and 1.53 kg/h, respectively. CO2 emissions in September were with the values of 0.507 and 0.657 kg/h for the municipal and the industrial wastewater treatment plants, respectively and N2O emissions were 5.4 and 1.2 kg/h, respectively. The Green Index of industrial wastewater treatment plant was lower than the municipal with the values of 1.29 and 1.33, respectively.
Keywords: Green index; wastewater treatment; environmental performance; greenhouse gases; global warming.
Impact of urban heat island effect on building heating intensity in Tianjin, China
by Fanchao Meng, Mingcai Li, Jun Guo, Lei Zhang, Jingfu Cao, Yuehao Chen
Abstract: In this study, the hourly variation characteristics of the urban heat island (UHI) and its impact on heating intensity of buildings were analyzed based on the observed hourly temperature data during the heating periods from 2009 to 2017 in Tianjin, a large city in Northern China. The results showed that the heating intensity considerably decreased due to the obvious increase in temperature over the past 9 years. The average annual heating intensity decreased by 8.08% and 10.30% with the increase of 1.46
Keywords: UHI effect; degree-hours; heating intensity; Tianjin city.
Measurement and Modeling of the Solubility of Dodecylcyclohexane in Supercritical Carbon Dioxide
by Xin Yang
Abstract: In developing the application of using supercritical carbon dioxide (sc-CO2) to extract fresh base oil from waste lubricant oil, the equilibrium solubility data is very valuable. In this study the equilibrium solubilities for one of the single lubricant oil component, dodecylcyclohexane, were determined in the temperature T=313.2 K, 328.2 K, 343.2 K, 358.2 K, 373 K and at pressures up to 17.76 MPa. Oil solubility is strongly dependent on the density of carbon dioxide (CO2), which increased with pressure at constant temperature while decreased with temperature at same pressure. The Adachi and Lu model provided the best regression analysis (R2) and the lowest average absolute relative deviation (AARD) in the examined experimental range, indicating the nonlinear equation of Adachi and Lu model best agreement with the experimental data.
Keywords: Supercritical carbon dioxide; Waste oil; Dodecylcyclohexane; Equilibrium solubility; Density-based model.
Global CO2 emissions mathematical modelling to
meet the 2015 Paris agreement on climate change
by Nizar Jaoua
Abstract: Future global carbon dioxide (CO2) emissions, consistent with the
2015 Paris Agreement on Climate Change, are explicitly predicted by using a
mathematical approach. Optimal designed models could serve as control tools
for the emissions to meet the climate accord. First, two categories of models are
produced: piece-wise linear, indicating the zero-emission time; and exponential,
for faster reduction of the emissions, which asymptotic behaviour allows their
long-term stabilisation slightly above zero. Further, suitable interpolations are
performed to get more developed versions; either to improve the UN climate
target or to add a smooth transition. A free parameter is involved in this
smoothing, therefore, providing an uncountable collection of models with short,
mid, or long transition. A common basis to the designed models is the remaining
budget of CO2 emissions. An explicit formulation of this global budget is
established in terms of the climate target. The graphical confrontation with UN
climate simulation models; the RCPs and no- and low-overshoot 1.5
Keywords: carbon dioxide; CO2; climate mitigation; global CO2 emissions;
mathematical modelling; Paris agreement; remaining CO2 budget; UN climate
Improving the stability and simultaneously capturing CO2 during biogas production under controlled internal pressure using NaOH
by Ishmael Matala Ramatsa
Abstract: The impact of operating parameters plays a very crucial role during anaerobic digestion, especially for the well being and healthy stability of the digester. The current phenomena in research is the coupling together of the digestion process and cleaning stage in one compartment with an aim of suppressing costs and energy involved in cleaning the gas. According to henry law, dissolution of carbon dioxide in the liquid water is directly proportional to its partial pressure. In the case of amount of biogas that was produced it was established in one of our published paper that as more of carbon dioxide dissolved the pH of the internal digester dropped and ultimately compromised the stability of the digester. To improve the stability of the digester two concentrations of NaOH were tested in a batch pressure digester at the pressure of 6bar. A significant amount of biogas and methane gas were recorded, both cumulative and daily biogas. The highest amount of biogas was recorded when the system was buffered with 2.66M NaOH solution, followed by the one without NaOH in daily productions. Cumulatively the amount of biogas produced when the system was buffered with 5.33M NaOH appeared to be higher that amount of biogas produced with buffer. In this current study, the methane composition at 0M NaOH, 2.66M NaOH and 5.33NaOH were 71.2%, 76.9 and 78.8% respectively. The results indicate that using a pressure digester and a buffer might be a promising approach when cleaning the gas. The results showed that at the buffer (2.66M NaOH) the system was more stable as evidenced by the amount of biogas produced. Furthermore at the same buffer more of carbon dioxide was captured as depicted in Fig 6.
Keywords: batch pressure digester; pH; ammonia-nitrogen; methane; carbon dioxide; NaOH; biogas.
Pros and Cons of Stratospheric Aerosol Injection
by Alberto Boretti
Abstract: Solar radiation management (SRM) geoengineering method of stratospheric aerosol injection (SAI) has been proposed to control global warming. The effect of sulphur injections at various locations in the stratosphere are studied by using climate models. These climate models have well-known limitations that are non-adequately addressed in the manuscript, specifically overrating the effect of the SO2 concentration. Examination of global temperatures reveals a smaller than assumed sensitivity to sulphates emissions, as well as to carbon dioxide emissions, and added phenomena missed in the models. Moreover, all the negative effects that the sulphur injections may have on the environment are neglected. Injection of sulphate particles into the stratosphere may thus have more downfalls than benefits, increasing environmental pollution without delivering significant warming reduction.
Keywords: Climate models; sulphate injections; CO2; temperatures.
Kinetic Based Extrapolating of Methane Production Potential for Seaweed/Food Waste Matrixes
by Hulya Civelek Yoruklu, Ahmet Demir, Bestami Ozkaya
Abstract: Seaweed accumulation result in undesirable environmental problems along the coastline of Istanbul. In this study, methane production potential of food/seaweed waste matrix was evaluated to explore how much of waste seaweed could be fed with food waste to an anaerobic digester at what rates of substrate to inoculum (S/X). Methane production potential data was modeled to describe the digestion kinetics by modified Gompertz, first-order, logistic function, and transference equation models. The anaerobic digestion was optimized as the S/X ratio up to 6 g VSsubstrate/g VSinoculum with the food/seaweed waste mixture of 2/3, in spite of observed inhibition when only food waste fed to batch reactors. The results indicated that seaweed was a useable agent with a good buffer capacity to improve performance of digesters arising from substrate inhibition. Transference function among applied models gave best fit to describe the kinetics of methane production potential at practical applications.
Keywords: Seaweed; The Marmara Sea; Food waste; Kinetics; Anaerobic digestion.
Interpretation of Alternative Environment-Friendly Gaseous insulator for SF6
by Hafiz Shafqat Abbas Kharal, Muhammad Kamran, Rahmat Ullah
Abstract: This work presents the testing of a unique composite gaseous insulating material using comparative evaluations with the properties of existing insulating materials. Main objectives of this research include the investigation of a novel composite insulating material with superior insulating properties, reduced cost, and less environmental hazard. Sulphur hexafluoride (SF6) is commonly used in current electrical insulation network but having recognized disadvantage of Global Warming Potential (GWP) 23,800 times larger than CO2. Due to this, it is an urgent need to find alternative of SF6 which is environment friendly. R12 and its mixture with different concentration of carbon dioxide with varying pressure are tested. Gaseous mixtures containing R12 gas demonstrate good dielectric properties with low-temperature usage possibilities. The insulation properties of SF6 and R12/ CO2 Gas mixtures with other merits and experimental set up are comprehensively discussed in this paper. The experimental study of power frequency breakdown voltage is also analyzed for a proposed gaseous mixture of R12/CO2.
Keywords: CCl2F2/CO2; global warming potential; environment-friendly; insulating material; power frequency; SF6 alternatives; insulation properties.
Toward understanding 1.5
by Yanyu Lu
Abstract: Limiting the global average temperature increase to 1.5
Keywords: climate extreme; global warming limit; long-term impact; model agreement; population.
Biogas and methane production efficiency of sewage sludge supplemented with conductive materials
by Yagmur Uysal, Burcu Mut
Abstract: Biogas production is one of the methods used in the recycling of sewage sludge which is a major problem for wastewater treatment plants to dispose. Methane is the most valuable content of biogas obtained from an anaerobic digestion (AD) process for energy production and accounts its 60-70% when the AD process is operated efficiently. Recently, researches have focused on accelerating this process and obtaining much more methane content from different wastes. For this purpose, various conductive materials are used in the AD process to accelerate electron transfer between bacteria populations. In this study, granular activated carbon (GAC) and magnetite (Fe3O4) nanoparticles coated with pectin were used to determine their effects on the biogas and methane production from sewage sludge. Laboratory-scale fermentation reactors were used, and the highest biogas production and its methane content (%) were determined in the sample containing of 2.0 g-PNC/gVSS as 554.3
Keywords: activated carbon (AC); biogas; Fe3O4; magnetite; methane; pectin.
Detrended fluctuation analyses of rainfall intensities: A case study
by Utku Zeybekoglu, Asli Ulke Keskin
Abstract: The main source of the irregularity in the rainfall regimes is global climate change. These irregularities in the precipitation regime cause sudden and heavy rains, which increases the risk of flooding especially in cities. Therefore, the investigation of the change in precipitation intensities over time has great implications in terms of hydrology, water resources and urbanization. In this study, rainfall intensity of Artvin meteorological station which is located in the Black Sea Region of Turkey is investigated. This station differs from the other stations in the Black Sea Region with extreme rainfall characteristics. Data of 14 standard duration rainfall intensity series with durations of 5 min to 24 h were used. First of all, two methods were applied for homogeneity control and then trend analysis was performed. Assuming that the factor destabilizing the homogeneity is the trend, a Detrended Fluctuation Analysis (DFA) was performed. After the implemention of DFA, homogeneity and trend analysis were re-applied to the data. In conclusion, it was determined that the main reason for the deterioration of rainfall intensity was the trend.
Keywords: global warming; rainfall intensity; homogeneity; DFA; trend; Artvin; Turkey.
Impact of substations equipment to the environment
by Cezar POPA
Abstract: The paper examines the main technologies used for the production of primary circuits for substations, average seasonal temperature fluctuations for primary circuits due to load and ambient factors variations correlated with the cost price and environmental impact in terms of space required for installation, CO2-equivalent emissions of equipment and other pollutants. An accurate assessment during the design stage, of environment risks and benefits of using a technical-economical solution can be a decisive factor in the strategy adopted to construct new substations or rehabilitate the existing ones.
Keywords: substation; greenhouse gases leakage; energy losses; environment pollution; CO2 equivalent emissions.
Gate-to-gate environmental life cycle assessment of hardwood lumber production
by Tanveer Ahmad, Uzma Noreen, Adam Taylor, Majid Hussain
Abstract: The objective of this study was to conduct a gate-to-gate life cycle assessment of hardwood lumber production in selected districts (Haripur and Abbottabad) of the Hazara region, Pakistan. Primary data regarding inputs and outputs from sawmills were collected through questionnaire surveys of twenty-two (22) sawmills in the Haripur district and eighteen (18) sawmills in the Abbottabad district of Hazara region, Pakistan during the year 2017-2018. Gate-to-gate life cycle assessment was conducted for a reference unit of 1.0 m3 of planed dry hardwood lumber. Production-weighted average data were modeled in SimaPro v.8.5 for ten environmental impact indicators. Diesel consumption in the transport of raw materials, purchased electricity consumed at the sawmills and urea formaldehyde resin used for filling cracks in the hardwood lumber product had the highest contributions to all the environmental impact categories evaluated. The total cumulative energy demand for 1.0 m3 hardwood lumber production was 5,842 MJ, with most of the energy (>80%) acquired from non-renewable fossil fuel sources such as petrol, CNG and diesel. The total carbon stock of 1.0 m3 hardwood lumber equals 1,047 kg carbon dioxide, whereas the carbon footprint of 1.0 m3 finished hardwood lumber equals 88 kg CO2e. Therefore, the carbon stock can be used to offset the carbon footprint by providing a net carbon flux of -959 kg CO2e per m3 of hardwood lumber production in Pakistan.
Keywords: Carbon stock; Environmental impacts; Hardwood; Lumber; LCA; Pakistan.
The effect of temperature on the development of immature stages of Aedes spp. against breeding containers
by Nazri Che Dom
Abstract: Temperature is often identified as the main environmental factor affecting the growth of the mosquito population. In this study, we examined the effect of constant temperatures on the developmental period of local Aedes albopictus and Aedes aegypti strains using environmental chambers. Based on the developmental data, it was found that the increase in temperature reduced the developmental period of the mosquito except for the first instar larvae. In addition, both strains were found to be able to develop and survive at all selected temperatures up to 33
Keywords: temperature; climate; Aedes; albopictus; aegypti; development; survival; humidity; breeding container.
ZERO WASTE MANAGEMENT: A CASE STUDY
by Ozge Koksal, Bilge Aydin Er, Yuksel Ardali
Abstract: Waste characterization is shown as the first step of a successful waste management policy. Many stages such as reduction of waste at source, separation according to property, collection, temporary storage, recovery, transportation, disposal and control must be carried out regularly and effectively. The studies were carried out to determine the amount of solid wastes generated and the characterization of the wastes produced in Ondokuz May?s University (OMU). According to the data, the total amount of solid waste production per week was calculated as 8597 kg/week. According to the waste characterization of the university, distribution rates are 51% for packaging wastes, 10% for non-recyclable wastes and park and garden wastes, 9% for construction waste, 9% for waste, 2% for organic waste, 2% for e-waste, 8% medical waste and 6% hazardous waste. After one year of monitoring at Ondokuz May?s University, studies have been initiated to manage the waste generated and the recycling potential and minimization of the existing wastes.
Keywords: Waste; management; characterization; zero waste; sustainability.
Special Issue on: GCGW-2019 Studies Associated with Global Warming
An Experimental Evaluation of Indirect Direct Evaporative Cooling Unit for Hot Climate
by Bourhan Tashtoush, Nelson Chilengwe, Mohammad Musthafa, Yousef Al Horr
Abstract: Direct and indirect evaporative cooling system is experimentally investigated using a plate heat exchanger for hot climate conditions. The effects of chilled water and ambient temperatures, water flow rates, humidity, and the operating cooling mode on the supply air temperature was investigated for three configurations. The system dry bulb and wet effectiveness was estimated for all conditions under consideration. It was found that the dry bulb effectiveness approached 17%, while it was in the range of 72-98% for the wet bulb effectiveness. In addition, the secondary air saturation efficiency was calculated with varying water flow rates. It was found that the increase of water quantity in the heat exchanger would increase the cooling capacity and lead to a higher secondary air temperature difference. This resulted in higher saturation efficiency for the system. These results were compared with available numerical data for calibration and validation purposes.
Keywords: Direct Cooling; Indirect Cooling; Cross flow; Wet Bulb Effectiveness; Dry Bulb Effectiveness; Saturation Efficiency.
Statistically Downscaling Climate Change Projection of Precipitation and Temperature over the semi-arid Yarmouk Basin- Jordan
by Fayez Abdulla
Abstract: The statistical downscaling model (SDSM) skills have been addressed in downscaling the climate over the Yarmouk Basin, which is a semi-arid trans-boundary basin between Syria and Jordan. The scenarios used to drive SDSM are GHGs Representative Concentration Pathways (RCPs) using CanESM2 GCM. The study findings illustrate that there is a good statistical confidence in the downscaling based on the uncertainty analysis results that have been performed. SDSM showed a good ability to simulate the mean characteristics of precipitation and temperature but a poor capability for capturing the daily precipitation pattern and extreme precipitation events. In addition, SDSM was found to tend to underestimate the precipitation amounts and the number of wet days. During the 21st century, all scenarios have agreed that the mean annual rainfall will continue to decrease while the temperature will continue to increase. The projected time series can be adopted with satisfying confidence for any intended climate change impact studies within the Yarmouk Basin.
Keywords: Climate change; Downscaling; SDSM; Semi-arid basin; Yarmouk Basin and Uncertainty.