Eco-sustainability analysis of precast-concrete utility poles manufacturing-A case study from Pakistan.

The civil construction sector is a major contributor to the emissions of greenhouse gases (GHGs), and accounts for 40 to 50% of the total GHGs emissions produced all over the world. Concrete utility poles are considered as pillars of power distribution systems in many developing regions of the world. This study has analysed the environmental sustainability of low-tension (LT) and high-tension (HT) types of precast-concrete (PC) poles used for power distribution in Pakistan. Life cycle analysis (LCA) method is used for the assessment of environmental burdens associated with the production-manufacturing stages of these PC poles. The LCA scores are illustrated for five impact categories: climate change, acidification, eutrophication, fine-particulate matter formation and fossil resource scarcity. The significant impact scores have been depicted in climate change and abiotic resource depletion categories as; 4.60E+01 kg CO2 eq. and 1.24 E+01 kg oil eq (for LT PC pole) and 1.55E+02 kg CO2 eq and 3.00E+01 kg oil eq (for HT PC pole), respectively. The analytics further depict that the manufacturing of PC pole is a highly energy intensive process, with significant hauling of raw materials and finished product which causes significant emissions and impact towards climate change and fossil resources depletion. Overall, this research can offer several novel contributions to the field of sustainable development and civil engineering, including a comprehensive analysis of the environmental impacts of the manufacturing process, the development of sustainable practices and technologies and the identification of the links between sustainable development and economic growth.

Techno-economic and environmental sustainability analysis of filament-winding versus pultrusion based glass-fiber composite technologies.

In the era of sustainable development, glass-fiber reinforced polymer (GFRP) composites have made their way into modern engineering, construction, and building sectors due to their exponential characteristics. While considering the rapid growth and development in this sector, this research has assessed the relative environmental and techno-economic sustainability of two sorts of GFRP composite technologies: (a) filament winding and (b) pultrusion to effectively appraise their application, merits, and demerits. This study will help low-middle-income countries like Pakistan toward cleaner production, environmental management, and sustainable industrial development. The techno-economic sustainability is determined by using life cycle costing and techno-economic indicators, i.e., benefit-cost (B/C) ratio, net present value (NVP), internal rate of return (IRR), and payback period. The B/C ratio depicts the relationship between the relative cost and benefits of a technology, and NVP expresses the calculated present value of the future payback stream of a technological investment, while the IRR is an effective techno-economic indicators which can predict the efficacy of an investment, and the payback period is the time forecast for a technology to recover its investments. These techno-economic analytics showed that the net life-cycle cost performance, B/C ratio, and IRR are 5%, 7%, and 15% higher respectively for filament winding-based GFRP technology than the pultrusion-based manufacturing technology, whereas overall net life cycle benefits are about 80% greater for filament winding. Similarly, the payback time is shorter for filament winding compared to pultrusion. The environmental sustainability is determined, by employing a relative life cycle analysis (LCA) for both technologies. The system boundary for the study is "gate to gate," i.e., manufacturing phase, where these technologies are assessed for their environmental externalities. The functional unit of "1 kg finished product," i.e., manufactured by pultrusion and filament winding technology, and eight life cycle impact assessment (LCIA) categories; climate change potential (CCP), terrestrial eco-toxicity potential (TETP), ozone depletion potential (ODP), fossil resource depletion potential (FDP), acidification potential (AP), eutrophication potential (EP), particulate matter (PM) formation, and water consumption potential (WCP) have been selected. The significant ecological impact scores are determined in the categories of CCP (kg CO2 eq.) as 10.8E + 00 and 5.01E + 00 and ETP (kg. 2,4-D eq.) as 1.26E-02 and 9.47E-03 and FDP (kg Oil eq.) as 3.96E + 00 and 2.59E + 00 for filament winding and pultrusion-based GFRP technologies, respectively. These LCIA results depicted that the ecological performance of filament winding technology is specifically better than pultrusion technology in the categories of EP, PM, and WCP, while, for all other life cycle impact categories, the pultrusion technology has depicted significantly lower impact potential and is environmentally more sustainable. The outcomes of this research will be greatly assistive for researchers, developers, manufacturers, and policymakers to effectively appraise the externalities and selection of a more sustainable GFRP technology.

Analysis of environmental sustainability of e-waste in developing countries - a case study from Pakistan.

The electronic waste generation rate is increasing drastically at a rate of 3 to 5% per year in developing countries. The aim of this study is to analyze the environmental sustainability and economic benefits of such e-waste management in the developing economies like Pakistan. The life cycle assessment (LCA) method has been employed for streamlined impact analysis of the end-of-life processing of e-waste focusing mainly on laptop computers and liquid crystal display (LCD) desktop computers in Pakistan. The method of cumulative exergy extraction from the natural environment (CEENE) has also been deployed for the relative assessment of resources' consumption of e-waste recycling versus landfilling scenario. The determined impact scores are 1.79E + 03 kg CO2 eq., 7.19E-07 kg CFC-11 eq., 1.02E + 03 kg 1,4-DCB, 7.13E + 01 kg 1,4-DCB, and 3.41E-03 kg Cu eq. in climate change potential, stratospheric ozone depletion, ecotoxicity potential, human noncarcinogenic potential, and mineral resource depletion impact categories, respectively. The results of CEENE analysis reveal that approximately 80% of the impact on natural resources is reduced by the efficient recycling of e-waste. The comparative assessment of respective scores for current and target material weight recovery (MWR) indicators represented that by increasing the MWR indicator by 33.8% for laptop computers and by 27.2% for LCD computers, the country will achieve an annual economic benefit of US $191.56 million. This is greatly significant for a transitional shift towards e-waste revalorization while realizing the objectives of sustainable resource consumption. Innovative improvement measures ensuring economically feasible, energy-efficient, and environment friendly waste collection, treatment, and recycling practices present an invaluable opportunity for developing countries.

Socio-economic and environmental impacts of COVID-19 pandemic in Pakistan-an integrated analysis.

The COVID-19 pandemic has affected about 210 countries with more than 67 million confirmed cases and over 1.5 million deaths across the globe including Pakistan. Considering the population density, health care capacity, existing poverty and environmental factors with more than 420,000 infected people and about 8300 plus mortalities, community transmission of the coronavirus happened rapidly in Pakistan. This paper analyses the short- and long-term effects of COVID-19 peak on the socio-economic and environmental aspects of Pakistan. According to the estimates, an economic loss of about 10%, i.e. 1.1 trillion PKR, will be observed in the FY 2021. Certain pandemic impediment measures like lockdowns, social distancing and travel restrictions taken by the Government have been thoroughly analysed to determine how they impacted the livelihoods of nearly 7.15 million workers. Consequently, a rise of 33.7% of poverty level is projected. While many negative impacts on primary, secondary and tertiary sectors of the economy such as agriculture, education and health care are observed, a drastic improvement in air quality index of urban centres of the country has been recorded amid lockdowns. With current economic crisis, fragile health care system and critical health literacy, a well-managed and coordinated action plan is required from all segments of the society led by the public authorities. Thorough assessment of COVID-19 scenario, management and control measures presented in this study can be assistive for the provision of policy guidelines to governments and think tanks of countries with similar socio-economic and cultural structure.

Waste valorization and resource conservation in rice processing industries-an analytical study from Pakistan.

The study aims to analyze and enhance the eco-efficiency of rice processing in Pakistan while focusing on pollution prevention, waste management, and valorization opportunities. Three rice mills were selected, and physical and chemical properties of their wastewater and solid waste were analyzed. It is depicted that rice husk has the highest share in the solid waste stream and possesses a significant renewable energy potential with a calorific value of 16 MJ/kg and a much lower energy cost of about 0.4 USD/MJ as compared to diesel and furnace oil, i.e., 36.8 and 26.2 USD/MJ, respectively. Recovery of commercially valuable by-products from the effluent of parboiling process is also investigated, and about 0.25 kg of starch/L from wastewater has been effectively reclaimed by wet milling method. The effluent water is also analyzed using Streeter-Phelps model which confirmed that value of contaminants in the wastewater of two of the selected rice mills exceeds the dilution capacity of the receiving body, with dissolved oxygen values at critical level as 0.54 mg/L and -20.7 mg/L respectively. Water pinch analysis and water cascade analysis (WCA) have also been employed to monitor and manage the water footprints. While the concentration composite curve depicted that about 0.8 ton/h of freshwater is saved by an application of smart water integration and pinch point was determined as 1814 ppm. While the WCA confirms that a total water demand of 45.3 kg/s at the third purity level has been reduced to 28.0 kg/s at the lowest purity level.

Sustainability and CDM potential analysis of a novel vs conventional bioenergy projects in South Asia by multi-criteria decision-making method.

In this study, the multi-attribute utility theory model, one of the most widely utilized multi-criteria decision-making methods, is employed to analyze the relative sustainability and cleaner development mechanism (CDM) potential of a novel bioenergy project in Pakistan and four registered CDM bioenergy installations in China, India, Sri Lanka, and Thailand. Four major sustainability evaluation criteria selected for the study are technology, economy, environment, and social aspects, whereas "simple multi-attribute rating technique" (SMART) and "additive synthesis method" were utilized for the calculation of weighting factors. The most significant indicator was emission reduction, and least significant indicator was job creation with 24% and 15% respective weightages, in the sustainability scoring. Moreover, for three considered evaluation scenarios, (I) base case, (II) per kilowatt, and (III) per kilowatt hour, the bioenergy project in Pakistan has the highest comparative sustainability values of 0.735, 0.592, and 0.492 respectively. This analysis will provide an insight assistance to developing countries for establishing sustainable energy installations under CDM.