International Journal of Global Warming (31 papers in press)
Thermodynamic assessment of information transmission in squids giant axon may explain why squid populations thrive with global warming
by Mustafa Özilgen, Bahar Hazal Yalcinkaya, Bayram Yılmaz
Abstract: Thermodynamic analyses are performed with two alternative sodium pump models to determine the effects of the global warming on information transmittance in the giant squid neuron. Squids are preferred in neuron studies since their giant axons allow easy experimentation. They are also highly susceptible to the effects of the global warming, since their organs function at the environmental temperature. One of the mathematical models showed that at 6.3 oC energy cost, exergy destruction and entropy generation were 1.77x10-11 kJ/cm2, 3.49x10-9 kJ/cm2 and 1.25 x10-11 kJ/K cm2, respectively. As temperature increases from 6.3 to 18.5 oC entropy generation is estimated to decrease by half, from 1.25x10-11 to 0.64x10-11 kJ/K cm2, implying that living becomes easier for the squid as temperature increases. The results were similar also with the other mathematical model. Outcomes of the thermodynamic analysis performed in this study may help to explain why the squid populations thrive with global warming.
Keywords: Global warming; neuronal energy; entropy generation; exergy destruction; activation entropy; sodium pump; Fermi energy.
Estimation of Shipping Emissions via Novel Developed Data Collecting and Calculation Software: A Case Study for the Region of Ambarli Port
by Kaan Ünlügençoğlu, Görkem KÖKKÜLÜNK, Fuat ALARÇİN
Abstract: It is known that emissions from ships always have higher values around port regions and made shipping one of the polluting industries in the world. The impact of shipping on global warming has recently received significantly more attention owing to a growing demand for decreasing global emissions. In this context, emissions from ships have been limited in accordance with the international shipping regulations such as EU-MRV (Monitoring, Reporting and Verification) and IMO DCS (Data Collecting System). In this study, web-based data collection software was developed to monitor emissions from ships. Furthermore; NOx, CO2, SO2, VOC, CO and PM emissions for June, July, August of 2017 has been calculated and monitored in real-time by considering year of construction, gross tonnage (GRT), main engine power, revolution and power of auxiliary engines, number of arrivals and cruising, manoeuvring and berthing time of all the ships. Moreover, emissions are categorized according to ship types, tonnage and flags. As a result, NOx, SO2, CO2, VOC, PM and CO emissions from main and auxiliary engines were calculated as 538.8 tons, 376.14 tons, 27332.03 tons, 33.11 tons, 53.68 tons and 22.1 tons, respectively with 1032 movement of 323 different ships that arrived in Ambarlı Port between the dates of 25.05.2017 and 22.08.2017.
Keywords: global warming; port emissions; green shipping; ship emissions.
CO2 adsorption performances of amine hybrid silica aerogels synthesized via in-situ polymerization of hybrid precursors
by Jiayue Zhang, Yong Kong, Xiaodong Shen
Abstract: Amine hybrid silica aerogels (AHSAs) were synthesized via a one-step sol-gel method under room temperature, using N-(2-aminoethyl)-3-aminopropyltriethoxysilane (AEAPTES) and tetraethyl orthosilicate (TEOS) as precursors. AHSAs with different amine loadings were synthesized by changing the TEOS/AEAPTES ratio. The specific surface area decreases with amine loading. The highest CO2 adsorption capacity was achieved when the amine loading was 11.90 mmol/g. The corresponding CO2 adsorption capacities with simulated air (417 ppm CO2), 1% CO2 and flue gas (9.68% CO2) are 1.86, 3.78 and 5.51 mmol/g, respectively. The amine efficiency of AHSA is up to 0.32. The as-prepared sorbent shows excellent cycle stability. The CO2 adsorption kinetics were also discussed.
Keywords: aerogel; sol-gel; CO2 adsorption; hybrid precursor; kinetics.
Thermodynamic Analysis of Solid Waste and Energy Consumption to Reduce the Effects of an Electric Arc Furnace (EAF) on the Environment
by Yildiz Koc, Huseyin Yagli, Enver Onur Ozdes, Ertugrul Baltacioglu, Ali Koc
Abstract: In this study, thermodynamic analysis of an EAF was made to reduce solid wastes and energy consumptions. Then, the slag formation, quicklime consumption and daily energy consumption of the EAF were optimised for different basicity ratios at constant silicium ratios (1.42%). Finally, the system is re-optimised for varying silicium ratios at constant basicity ratio (1.87). As a result of the study, it was seen that the energy consumption was reduced by about 153.26 GJ per day and the mass efficiency of the system was increased from 92.60% to 95.33%. This energy saving is equal to 1987016.11 kWh, which is equivalent to the nearly 1152 tones CO2 reduction per day.
Keywords: Electric arc furnace (EAF); waste management; thermodynamic analysis; optimisation; chemical-based mass balance; energy saving.
Determination of Spatial Distribution of Topsoil Organic Carbon Stock Using Geostatistical Technique in a Karst Ecosystem
by Turgay Dindaroglu, Recep Gundogan, Mustafa Omer Karaoz
Abstract: This study aimed to determine the spatial distribution of total soil organic carbon (TSOC) content in surface soils in the karst ecosystem located in the Mediterranean region of Turkey. Land use types and depression areas were determined using Landsat8 and Shuttle Radar Topography Mission (SRTM) data, respectively. Topsoil samples (0-10 cm) were collected in 108 sites and analysed for soil pH, SOC, bulk density (BD), total nitrogen content (N) and particle size distribution. The exponential model was the best model to describe SOC contents, stable model for BD and circular model for TSOC. The SOC content in different land uses ranked as forest (4.10%)>rangeland (2.60%)>cropland (1.41%) areas. Mean TSOC content was identified as 27.22 MgCha-1 in non-depressed areas and 48.71 MgCha-1 in depressed areas. TSOC dramatically changed from none-depressed areas to depressed areas were identified in cropland (ΔTSOCcropland=68.05%). Forest areas were more stable in view of the change of carbon sequestration compared to the other areas (ΔTSOCforest3= 28.24%). Depression areas play very important role in terms of carbon storage capacity in the Karst ecosystem.
Keywords: soil carbon; sequestration; depression area; environmental modeling; geostatistics; karst area; land use; topsoil; spatial analyses; carbon stock.
A Review of CO2 Emission Reductions due to Wind Turbines Using Energy Benchmarks; a focus on the Irish Electrical Energy Market
by Tony Kealy
Abstract: The installed capacity of wind turbines in Ireland increased from a value of 2,250 MW in 2014 to 3,318 MW in 2017, a 43% increase in the four years, supported through climate mitigation policies. The main aim of this study is to determine if the increase in wind turbine installed capacity is impacting on efforts to reduce CO2 emissions. The study utilises a review methodology. The findings show that the steady rise in wind turbine installed capacity year-on-year is not reflected in the Irish CO2 g/kWh energy benchmark. The benchmark value was 457 g CO2/kWh in 2014 and 437 g CO2/kWh in 2017, an improvement of just 5%. There is no consistent correlation between the increase in wind turbine capacity and a reduction in CO2 emissions. Future research into the quality of the wind turbine power output is recommended, in particular, the variability aspect in the power output signal.
Keywords: Wind Turbines; Stakeholders; Energy Benchmarks; CO2 Emissions; Review; Ireland.
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.
Impact of climate change on cultural heritage: a simulation study to assess the risks for conservation and thermal comfort
by Guilherme Coelho, Hugo Silva, Fernando Henriques
Abstract: Artefacts are prone to various types of decay depending on the indoor conditions of the building in which they are kept. Moreover, due to climate changes, the indoor climate of these buildings may significantly change, which can endanger their preservation. Hence, this paper studies the effects of climate changes on the indoor climate of heritage buildings and on the conservation of artefacts and thermal comfort of visitors. For this purpose, a validated hygrothermal model of a naturally ventilated historic church Saint Christophers in Lisbon coupled with climate change weather files were used to obtain future indoor conditions. Additionally, four other climates were simulated using the building model: Seville (Mediterranean climate), Prague and Oslo (Continental climate), as well as London (Oceanic climate). The obtained indoor climates were assessed using a statistical analysis based in several known indices, a risk-based analysis and an adaptive thermal comfort model.
Keywords: climate change; preventive conservation; church; historic building; computational model; risk-based analysis; artefacts conservation; thermal comfort; hygrothermal behaviour; cultural heritage.
Characterization of Spatio-Temporal Trend in Temperature Extremes for Environmental Decision Making in Bangladesh
by Md. Mohsan Khudri, Md. Shaddam Hossain Bagmar, Asef Mohammad Redwan
Abstract: Spatial and sequential variability of extreme temperature events enthral the scientific community owing to their significant impact on global climate change and cataclysmic consequences on human sustenance and socio-economic development. This study analysed trends in monthly data of minimum and maximum temperature of 23 meteorological stations of Bangladesh. Mann-Kendall test was applied to characterize the trends in temperature extremes with their spatial and temporal patterns. The minimum and maximum temperature of the country ranged from 0
Keywords: Temperature; Climate Change; Trend Analysis; Environment; Bangladesh.
Special Issue on: GCGW2018 Special Issue for Potential Energy Solutions for a Better Environment
A time-varying carbon intensity approach for demand-side management strategies with respect to CO2 emission reduction in the electricity grid
by Can Coskun
Abstract: The main aim of this study was to determine electricity utilisation based on the hourly distribution of CO2 emissions. Turkey was chosen for this case study because of the CO2 intensive characteristics of electricity generation. This study aims to be a pioneer in the spread of a time-varying carbon intensity approach for the calculation of carbon foot prints. Electricity generation-based hourly emissions are calculated by utilising actual data. It varies from 418.6 g CO2/kWh to 824.6 g CO2/kWh, or 597.8 g CO2/kWh on average. According to hourly basis analyses, the highest CO2 intensity of electricity generation occurs between 06:00 and 07:00. The highest CO2 intensity of electricity generation occurs on a Sunday despite this being the time of lowest electricity demand. An annual total of 162.84 metric tons of CO2 is released into the atmosphere as a result of electricity generation. Electricity generation-based CO2 emission per capita is calculated as 2.04 ton CO2.
Keywords: electricity generation; CO2 intensity of electricity generation; CO2 emission per capita; global warming; demand-side management; time-varying carbon intensity; Turkey.
Biogas production from sunn hemp
by Nusara Sinbuathong, Roj Khun-Anake, Suriya Sawanon
Abstract: Sunn hemp at a cutting age of 50 days was investigated for biogas production by studying the anaerobic digestion of sunn hemp alone and the co-digestion of sunn hemp with cow dung at a concentration of 20% by fresh weight but with various proportions. The single-stage, semi-continuous reactors were operated at a hydraulic retention time of 40 days. Mixed ruminal microorganisms from cows were used as inoculum. The results indicated that the CH4 content from the digestion of sunn hemp alone was 47.57% and the CH4 produced per area of cultivation was 9,231 m3/hectare.year. Co-digestion could increase the CH4 content to greater than 50%. Proportion of sunn hemp:cow dung:water of 10:10:80 by fresh weight was optimal for co-digestion. At this recommended ratio, the CH4 yield reached 412 L/kg total volatiles solids degraded. Sunn hemp could be a very good renewable energy source for biogas production.
Keywords: anaerobic digestion; bioenergy; biogas; co-digestion; cover crop; cow dung; global warming; green manure; methane; renewable energy; sunn hemp.
Waste management and determination of carbon footprint of a marine port: a case study from Izmir, Turkey
by Neval Baycan, Yiğit Pehlivan
Abstract: Greenhouse gas reduction, development of renewable energy sources, and energy efficiency represent the main supports of sustainable development. There is a growing interest for the quantification of corporate level carbon footprints as a result of the international climate policy and emerging consumer awareness. First objective of this study mentions to environmental effects of harbours and ports. What kind of waste is given by ships, amount of wastes, their disposal processes are studied. The second objective of this work is to calculate the carbon footprint of the port that is located in the city centre based on emission sources of ships. The inventory analysis mainly uses primary data collected from the port. The number of ships coming to the port and their types of engines and amount of fuels were taken into account in the calculation of the carbon footprint. Every type of engine has different operation modes. The results of this study show that the port has a carbon footprint 65043 tonnes CO2 equivalent per year.
Keywords: waste management; global warming; greenhouse gases; carbon footprint; ports; Turkey.
The effect of phase change material incorporated building wall on the CO2 mitigation: a case study of Izmir, Turkey
by Mustafa Asker, Ersin Alptekin, Ayça Tokuç, Mehmet Akif Ezan, Hadi Ganjehsarabi
Abstract: Buildings are considered to be one of the considerable energy consuming systems and greenhouse gas emissions sources, and 14% of this energy is used for cooling. This paper evaluates the energetic benefits and CO2 emissions of incorporating phase change materials (PCMs) on the facade of an office building under real weather data conditions for Izmir, Turkey for cooling. For this purpose, two situations, specifically the effect of the melting temperature (27°C, 32°C and 37°C) and the location of PCM (interior, middle and exterior of the wall) have been investigated for five months, from May to September. The results indicate that integration of PCM with a melting temperature of 32°C at the interior section of the wall in the hottest months of the year, namely June, July, and August reduce the related CO2 emissions by 50.15, 122.339 and 121.727 kg CO2 respectively, compared to the baseline configuration without PCM.
Keywords: building energy consumption; building wall; CO2 mitigation; phase change material; PCM; thermal energy storage; TES; Turkey.
Addressing environmental implications of crop stubble burning in Pakistan: innovation platforms as an alternative approach
by Waqas Ahmed, Qingmei Tan, Sharafat Ali, Najid Ahmad
Abstract: Pakistan's eastern provinces are very badly affected by haze and smog caused by burning of rice straw and stubbles after reaping season. This practice causes emission of greenhouse gases and pollutant materials which not only has severe health consequences but also the main source of traffic disturbance and accidents due to poor visibility. A ban on burning of crop residue deems to be ineffective without alternative means and consultation of farmers. Previous studies were aimed to figure out causes, contributing factors and impacts of stubble burning, but largely ignored farmers choices and market environment. In this study, a survey-based farmers' preference order was obtained through hybrid AHP-TOPSIS model. The analysis traces out why most of the farmers prefer open field burning. The present study proposes a national residue management service (NRMS) platform based on preferences of the alternatives and considering market externalities. This research provides an appropriate mechanism and policy suggestions to policy makers and practitioners that may help in minimising the environmental impacts due to improper management of the crop residue.
Keywords: climate change; global warming; environmental protection; crop residue; burn; analytical hierarchy process; AHP; TOPSIS; innovation platform; Pakistan.
Estimation of emissions from crop residue burning using remote sensing data
by Kubra Bahsi, Betul Salli, Doğushan Kılıç, Elif Sertel
Abstract: Approximately one-fourth of the population in Turkey works in the agricultural sector. One common problem in agricultural waste removal is the adverse effects of crop residue burning (CRB) on public health and environment, after the harvest. In this research, a pilot study area of 225 km2 (15 km × 15 km) in the Southeastern Anatolia Region of Turkey was selected where CRB is a common practice. Sentinel-2 satellite images of the pilot area were obtained and processed in order to monitor the spatial distribution and the total area of the agricultural parcels where crop residues were burned in the field. The analysis was extended to find out the crop-specific emissions from residue burning by identifying the crop type for each agricultural parcel. Total emissions of CO2, CO, CH4, NMHC, N2O, NH3, SO2 and NOX from the study area as a result of CRB were calculated based on the previously reported emission factors and their implication for air quality and the atmosphere was assessed.
Keywords: crop residue burning; agriculture; remote sensing; air quality.
Photodegradation of olive mill wastewater with sunlight using nano-ZnO-SiO2 composite, its reusability and the quality of treated water
by Çağlar Ulusoy, Delia Teresa Sponza
Abstract: In this study, nano-ZnO-SiO2 was used to treat pollutants from olive mill industry wastewaters (OMW) by photo-degradation. The effects of increasing nano-ZnO-SiO2 concentrations (0.5 g/L, 1 g/L 3 g/L, 5 g/L and 10 g/L), photooxidation times in sunlight (8, 16, 24 and 36 hours) and different pHs (4, 7 and 10) were evaluated in the treatment of OMW pollutants. The maximum pollutant yields for chemical oxygen demand (COD), total phenol and total solids (TS) were 77%, 73% and 64% with a nano-ZnO-SiO2 concentration of 3 g/L after 24 hours of sunlight irradiation at pH 4.It was found that the treated olive mill wastewater (OMW) can be used again after eight sequential treatments with total COD and total phenol yields as high as 99%. The treated water was evaluated based on irrigation purposes. The total cost to treat 1L of OMW containing the seven nano composite expenses is 1.95 euro.
Keywords: ZnO-SiO2; photocatalytic degradation; olive mill wastewater; OMW; sunlight irradiation; reuse; recovery.
Biodesign as an innovative tool to decrease construction induced carbon emissions in the environment
by Onur Kırdök, Tutku Didem Altun, Deniz Dokgöz, Ayça Tokuç
Abstract: Around 40% of the Earth's carbon emissions are caused by the construction sector, mainly related to materials extraction and energy requirements. Therefore, architects and engineers are looking for solutions to achieve zero carbon emissions with their designs and production methods. This paper aims to investigate innovative construction methods, which are possible by linking the fields of biology and architecture; hence, use them to decrease carbon emissions during construction activities. Although using biomaterials and learning from the examples of and imitating nature is not a new idea, contemporary technological advances and scientific understanding made it possible to emulate more complex ideas from nature. This paper studies three biodesign projects; Neri Oxman's silk pavilion, Wolf Hilbertz's sea-autopia ampere and Biodesign Team Turkey's (TBT) sand architectures to investigate if a low carbon architecture and construction that makes use of biodesign is possible. The innovative construction methods in the cases make use of creatures and natural processes to decrease the amount of raw materials in architectural production, decrease the need for transportation by environmentally friendly onsite production and reduce many steps in the construction process; thus, make it possible to decrease carbon emissions compared to conventional construction methods.
Keywords: bio-architecture; bio-based material; biodesign; eco-construction; sustainability; Neri Oxman; silk pavilion; Biodesign Team Turkey; TBT; sand architectures project; Wolf Hilbertz; sea-autopia ampere; future architecture; bio-calcification; bio-rock; bio-fabrication.
Bioremediation of minkery wastewater and astaxanthin production by Haematococcus pluvialis
by Yu Liu, Ilhami Yildiz
Abstract: A two-stage system was designed for culturing and induction processes of H. pluvialis. H. pluvialis was cultivated in minkery wastewater and compared with the conventional Bold's basal medium, and grew better in diluted (1.5%) minkery wastewater, yielding a biomass production of 906.3 ± 34.0 mg L−1. Total nitrogen and total phosphorus were also removed successfully. In the following induction stage, nitrogen-deprived vegetative cells were exposed to high light intensity for astaxanthin production, and the resultant production was 39.72 ± 1.69 mg L−1. Employing the diluted wastewater, a mixotrophic induction strategy was also tested by using a series of acetate and NaCl concentrations. The findings indicated that the optimal combination for astaxanthin production was 38.14 mM acetate and 0.58% (w/v) NaCl. And the optimal astaxanthin concentration was 67.95 ± 3.93 mg L−1 after a 12-day induction period. This study concludes that H. pluvialis offers a potential opportunity for treating minkery wastewater and producing high-value astaxanthin.
Keywords: bioremediation; minkery wastewater; water pollution; wastewater treatment; Haematococcus pluvialis; algal biomass; astaxanthin; photoautotrophy; mixotrophy; nutrient deprivation; nutrient stress; light stress; surface response methodology; Nova Scotia.
Investigation of lipid, carbohydrate and protein production from Chlorella vulgaris in controlled environment minkery wastewater
by Yuchen Ji, Ilhami Yildiz
Abstract: In an effort to incorporate a novel bioremediation technology into minkery wastewater treatment systems, this study aimed to investigate the effect of light cycles on the simultaneous production of Chlorella vulgaris biomass, lipid, carbohydrate, and protein in controlled environment minkery wastewater. Diluted minkery cage-washing wastewater used in the experiments, which were designed as a completely randomised design with a single factor (light cycle) experiment. The single factor had four levels: six-day continuous light (photoautotrophic), 48-h light/24-h dark (mixotrophic), 24-h light/48-h dark (mixotrophic), and six-day continuous dark (heterotrophic) cycle, which were randomly assigned to the 2.25-litre vertical column controlled environment photobioreactors (PBR), each equipped with an independent cool-white fluorescent light (8 W, 6,700 K) operated at room temperature. The pH in each PBR was monitored and controlled using independent pH meters and air pumps. During six-day cultivations, continuous light and 48-h light/24-h dark cycles achieved the largest biomass (82.50 mg L−1 day−1 and 79.50 mg L−1 day−1, respectively) and protein productivities (42.62 mg L−1 day−1 and 38.79 mg L−1 day−1, respectively) out of Chlorella vulgaris in minkery wastewater; however, using 48-h light/24-h dark cycle instead of continuous light cycle would reduce the energy cost of cultivation. The light cycles of continuous light, 48-h light/24-h dark, and 24-h light/48-h dark achieved the highest lipid (15.06 mg L−1 day−1, 16.03 mg L−1 day−1, 12.82 mg L−1 day−1, respectively) and carbohydrate (11.15 mg L−1 day−1, 11.89 mg L−1 day−1, 8.08 mg L−1 day−1, respectively) productivities, and there was no statistically significant difference in between; however, using 24-h light/48-h light cycle would again reduce the energy cost of cultivation compared to the other two cycles. Overall, for the cultivation of Chlorella vulgaris in minkery wastewater, the most appropriate light cycle for the production of microalgae biomass and crude protein seems to be the mixotrophic growth under 48-h light/24-h dark cycle, while the mixotrophic growth of 24-h light/48-h dark cycle was the most appropriate system for the production of lipid and carbohydrate. Providing a supplemental organic carbon source, preferably from another waste stream, has a potential to change the story with respect to the competitiveness of continuous dark (heterotrophic) cycle, and studying other microalgae strains may make minkery wastewater even more competitive compared to traditional culture mediums.
Keywords: bioremediation; minkery wastewater; water pollution; Chlorella vulgaris; microalgae; lipid; protein; carbohydrate.
Investigation of microbial communities in the field-scale co-composting of sewage sludge and organic municipal solid wastes
by Şenol Yıldız, Emre Oğuz Köroğlu, Ahmet Demir, Bestami Özkaya, Osman Atilla Arikan
Abstract: The alternative methods should be used to treat sewage sludge and municipal solid wastes which are mostly landfilled in Turkey. Therefore co-composting of these waste streams is a suitable disposal method yielding a useful product. The aim of this study was to investigate the microbial community during the field scale co-composting of sewage sludge and organic municipal solid wastes with addition of bulking agents. Aerated static pile of approximately 26 m3 was used for composting process during 56 days. Investigations of diversity dynamics depending on the temperature were determined by denaturing gradient gel electrophoresis and sequencing of bacterial 16SrDNA-PCR products. The variations of physicochemical parameters and biodegradability during the process were also monitored. The results showed that most of microbial group's role in composting process was temperature dependent and composting was designated by its characteristic thermal profile.
Keywords: aerated static pile; composting; microbial community; organic municipal solid wastes; sewage sludge.
Development of seasonal solar radiation estimation models for Dokuz Eylul University campus area for controller of a two-axis solar tracker
by Tuğçe Ünver, Aytaç Gören
Abstract: In urban locations, it is generally hard to find enough spaces for solar power plants. However, micro-energy generation systems like solar trackers can be located even in crowded cities and becoming a significant technology in solar energy systems. In this study, the measured global solar radiation data for the research area, Tinaztepe/Izmir (38°22'15.3"N 27°12'28.5"E), were logged, then analysed using statistical methods and seasonal daily global solar radiation mathematical models of Tinaztepe/Izmir were developed. The results of these mathematical models give more precise daily average solar radiation value for Tinaztepe/Izmir than previous Izmir global solar radiation models.
Keywords: renewable energy; solar radiation; solar tracker.
Techno-economic evaluation of a residential roof-mounted solar system and its power generation: a case study in Canada
by Azzam Abu-Rayash, Ibrahim Dincer
Abstract: In this paper, a case study is presented where a residential solar system in Kitchener, Ontario is analysed economically as its annual performance is also assessed. The recorded data for this system are investigated further to better assess its technical performance. Optimal annual performance is observed when the temperature is at 18°C and when the wind speed is at 3.8 m/s. The modelled system without the battery correlates closely with the actual installed system. In fact, the actual return on investment (ROI) for the system is 19.75% while the modelled ROI is 23.5%. The payback time of 5 years is another major highlight of this system. Finally, the greenhouse gas (GHG) emissions of the current system total up to 38,000 kgCO2e/kWh.
Keywords: solar energy; photovoltaics; thermoeconomics; battery storage; performance assessment; cost analysis.
Impact of thermal mass for future energy consumption: case study in adobe house
by Zeynep Durmuş Arsan, Ekin Gamze Yöney
Abstract: This paper examines thermal mass quality of building envelope as passive preventive phenomena for future energy consumption. It questions how much and what type of thermal mass is required for decreasing energy consumption according to future climate change. Summer energy performance of adobe house in Konya, Turkey is studied in terms of thermal mass characteristic by using dynamic simulation software. Measured and predicted microclimate data for 2017 and 2050s are used to compare passive impact of wall material choices, i.e. adobe, limestone, vertical hollow brick and volume of wall without night-time ventilation. In conclusion, the study reveals that thermal mass with lower density and thinner materials show higher energy performance for summers. Energy consumption is minimum with vertical hollow brick wall in 50 cm for 2017 and 30 cm for 2050s. It is deduced that thermal conductivity will still have higher impact than thermal mass on energy consumption.
Keywords: thermal mass; energy consumption; adobe brick; climate change; dynamic simulation.
Special Issue on: IEEES-10 Environmentally Benign Solutions for Better Sustainability
DEPTH FUNCTION OF STORED AND SEQUESTERED CARBON IN COTTON GROWING SOILS OF SOUTH GUJARAT IN INDIA
by Sureshkumar Bambhaneeya, Amresh Das
Abstract: Mean SOC stock at 0-15, 15-30, 30-60, 60-90 and 90-120 cm soil depth of irrigated profiles were 15.0, 12.6, 21.5, 19.3 and 15.3 t ha-1, respectively. Similarly, mean SOC stock at an above various soil depth of rainfed profiles were 12.2, 10.0, 19.3, 15.6 and 12.7 t ha-1, respectively. SOC stored/sequestered in micro-WSA (< 0.25 mm) in irrigated profiles varied widely from 1.7 to 11.7 tha-1, while the same in rainfed profile soils varied from 1.4 to 20.5 t ha-1. Mean of irrigated profiles with respect to carbon stock associated with micro-WSA < 0.25 mm was found slightly lower (5.7 tha-1) than that of rainfed profiles (6.0 tha-1). Thus, WSA < 0.25 mm size acts as storing/ sequestering C within it for long periods.
Keywords: Carbon; Cotton; Sequestered carbon; Depth function; South Gujarat.
Multiscale interaction between energy and food quality in the super cold chain for sustainable agriculture
by Yi-Sai Gao, Guan-Bang Wang, Ya-Ting Xiao, Jia-Qi Sun, Qiu-Yun Zheng, Xin-Rong Zhang
Abstract: For the cold chain of fresh agricultural food, a good balance between energy and quality must be carefully considered. Most of previous researches focused on macroscale and mesoscale, while neglecting the significance of microscale. In the present study, the super cold chain is extended to multiscale studies on the interaction between energy and food quality by illustrating four representative cases. At microscale and mesoscale, such methods as X-ray computed tomography and stochastic reconstruction are adopted to analyse the multi-phase and multi-component porous structure. At macroscale, the dissipation factor is applied to evaluate the heterogeneity and optimize the system. Besides, representative volume element (RVE) method is a bridge between different scales, and heat and mass transport are solved simultaneously. Therefore, based on the special focus on sustainable agriculture, super cold chain has the potential to achieve less food quality loss and lower energy consumption, thereby decreasing effects on global warming.
Keywords: Super cold chain; energy; food quality; sustainable agriculture; multiscale studies.
Comparative analysis of various refrigerants used in transport refrigeration based on thermodynamics and environmental performances and cold chain management
by Enver Yalcin, M. Ziya Sogut, Onder Altuntas, T. Hikmet Karakoc
Abstract: In cooling systems, besides the refrigerant preferences, the probability of leakage due to dynamic conditions increases energy consumption and emissions directly or indirectly. In this study, thermodynamics and environmental performances of transport refrigeration systems using different and alternative refrigerants were examined. Leakage effects of refrigerants on the environment were investigated in terms of energy consumption and emission loads based on the coefficient of performance, exergy efficiency and improvement potentials. R152A stands out between the refrigerants taken as a reference with aspects of cooling capacity, environmental effects and refrigerant charge amount.
Keywords: transport refrigeration; COP; exergy analysis; leakage rate; CO2 emission.