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The use of alternative energy sources has become increasingly imperative due to the increasing demand for global energy and the depletion of fossil fuel reserves. Biomass stands as a key player in addressing both current and forthcoming energy challenges, serving as a promising solution to fulfill the heightened need for energy resources. This study focused on investigating the impact of temperature variation during the pyrolysis process on the resultant yield (syngas, bio-oil, biochar), as well as examining the physicochemical characteristics of energy, and exergy output. To accomplish this, a cylindrical pyrolysis reactor was specifically designed and utilized for the experimentation, employing wood sawdust with particle sizes ranging from 0.1 to 30 mm as the primary feedstock. The experimental investigations and subsequent thermodynamic analyses were conducted through a temperature range of 250 to 450 °C, employing a heating rate of 10 °C/min. The findings revealed a direct correlation between the increase in pyrolysis temperature and the enhanced output of bio-oil and syngas. Optimal yields were observed at different temperature values, with bio-oil peaking at 450 °C (55 %) and biochar at 250 °C (60 %). Furthermore, bio-oil yield notably reached 47 % with particle sizes below 0.1 mm. The viscosity of the produced bio-oil averaged between 2.06 and 3.55 mPa s, while the density consistently approximated 1.05 g/cm3 across all cases. Detailed analyses including chemical and physical characteristics were conducted utilizing Fourier-transform infrared spectroscopy (FTIR), gas chromatography–mass spectrometry (GC–MS), field emission scanning electron microscopy (FESEM), and energy-dispersive X-ray spectroscopy (EDX). The observation and quantification of CO, H2, CH4, and CO2 were part of the analytical process. This study shed light on the significance of temperature control in optimizing the output of valuable energy products from biomass pyrolysis, the potential for sustainable energy production, and the involved interplay of variables influencing the process.

Flat plate solar collector (FPSC) and parabolic trough solar collector (PTSC) are widely used for residential solar water heating (SWH) applications. This work studied two different solar collector systems. Nanofluid and its influence on the residential solar water heating (SWH) systems were investigated. The two SWH systems were designed, installed, tested, and compared at varying mass flow rates (mf) of 0.47, 1.05, and 1.75 kg min−1 in ambient environmental conditions. The comparative study was conducted according to thermal efficiency (ηth), useful energy gain (QU), stored energy (QS), outlet hot water temperature (To), and difference temperature (ΔT) between the cold inlet and hot outlet water from the collectors. The analysis of outcomes showed that the PTSC was more efficient than FPSC. The FPSC and PTSC systems performance were investigated using two different types of nanofluids. Carbon nanotubes in water and ethylene glycol were utilized. A remarkable improvement in the average thermal efficiency 64.1 % and 80.6 % of FPSC and PTSC systems using ethylene glycol nanofluid were obtained respectively. The total reduction in CO2 emissions was 31.26 kg/day and 39.28 kg/day for the FPSCs and PTSCs, respectively in the presence of ethylene glycol nanofluid. A significant saving in CO2 release is owing to the renewable clean energy of solar collectors.

Climate change and uncertainties in energy transition continue to increase the risk of environmental pollutions. The need fornew materials derivable from organic materials have opened several new frontiers in research and innovation. Polymer-based materials (PBMs), considering its versatility, have shown their potentials in engineering structures and, the results are promising andfar-reaching. PBMs possesses excellent thermal, mechanical and chemical properties, which necessitated significant research interest in these materials, resulting in their involvement in building and construction works. However, as their needs widened, spanning all human endeavours, it therefore important to establish how best these materials could be deplored in the face of climate change. Part of what is necessary as we explore these materials, is to report how best these materials could be applicable in building and construction works due to their low thermal conductivity’s values and their biodegradability properties. The application of natural fibres is noticeable everywhere with possibility of being used the more if containment measures are put in place to reduce its vulnerability. Thisreview paper x-rays the natural fibre materials as a reliable reinforcement in building structure and this assertion is premised on its peculiarities and thermal properties. As established in many published papers, natural fibre is of lower thermal conductivities values, compared with other materials in building reinforcements. This discussion would be all encompassing, providing details on how natural fibre could assist in energy conservation in building and equally saves considerable cost in construction works.

The staggering increase in water production, driven by population and economic growth, has consequently led to a massive increase in energy demand, particularly in countries that rely on desalination. Hence, the concept of the water-energy nexus has emerged as the best option to alleviate the gap between the demand and production of both water and power. This paper proposes a new approach for co-optimizing water and electric power systems by incorporating the energy-intensive equipment involved in water desalination and distribution. The proposed procedure leverages the energy flexibility of reverse osmosis (RO) desalination tracks. RO tracks can operate alternatively in conjunction with water network storage tanks with variable-speed pumps to optimal satisfy water demand at minimum energy and operating costs. The developed model takes into consideration the essential constraints of both the power and water systems to meet consumer demands. Further, a mixed-integer nonlinear programming model is proposed for the day-ahead operation of the two integrated systems. The simulation findings show that the suggested technique is successful in scheduling the energy-intensive equipment in the two systems to achieve a $\$ $ 26,993 per day savings compared to a 4.6% decrease in overall operating costs when compared to optimizing each system independently.

Disruption of ecosystem, following biodiversity loss, have all been attributed to climate change. Sustaining the natural cycle, amid environmental vulnerability, is a great task facing many nations today, most importantly, developing countries of the world. Several measures, earlier proposed in the literature, appear not to have mitigated the overbearing impact of climate change, in which their resultant catastrophes are now prevalent and unprecedented. The use of natural resources to produce lighter weight materials for building and automobile industries, have helped to conserve fossil fuel energy, no doubt, but this is without its shortcomings. These natural resources, which ought to be protected, are now been encroached, and in some cases, being a harbor for modern innovation. Adaptation of natural resources as a conservative measure, requires a synergy and clear-cut approach in the material value chain, in order to produce a comparative lighter component part. The use of biodegradable materials as the replacement part in many metallic materials, remains the best approach, no doubt, but how do we protect and conserve these natural resources, as they are being depleted for energy saving measures? In this scientific paper, the authors review existing practices, leading to environmental vulnerabilities and several measures fueling climate change crisis. Substantial part of the contributing factors are material composition and energy use. As human activities increase, the attendant interference on biodiversity and environment would be far-reaching and unpredictable, resulting in further disruption in the ecosystem. Natural resources, being our last resort, is now faced with extinction of large scale, and it is now of essence to bridge the identifiable gaps before the mother nature is completely destroyed. Some of these effects have already been felt in climatic weather changes, land degradation, greenhouse gas emission, contamination of underground water and biodiversity loss. The other leg of the gap is energy use, and how effective would developing and emerging countries leverage on energy transition in the face of technological and trust rivalry among nations of the world? This paper provides further measures in tandem with current realities, on how some of the existing conservation methods could be reinforced, in the light of myriad of ecological challenges threatening human existence. If natural resources, i.e., natural fibers, were to be used as energy saving measures, what would be the replenishment strategies and environmental impact assessment of such action, considering the dependence of man on these natural resources? Findings and conclusions drawn from this paper could be useful to researchers and would-be stakeholders in the climate adaptation policies and several other interest groups on preservation advocacy.

Membrane-based gas separation continues to be an area of interest that is being explored for various applications and efforts are being made to enable large-scale implementation and commercialisation. Works on techno-economic studies in areas such as carbon capture, natural gas sweetening, and biogas upgrading has been reported. Various simulation studies have reported the effect of the membrane flow pattern on permeate recovery and purity. The simulation studies in this area have been limited to single-stage and two-stage membrane processes, while many of these studies considered polymer membranes, facilitated transport has barely been investigated. In addition, optimisation studies that compared different flow patterns in the membrane module have been few. The facilitation of gas permeation decreases as pressure is increased due to carrier saturation. However, an increased pressure increases the driving force, and a trade-off should be achieved. The different membrane flow patterns also have inherent driving force potential. In this work, a superstructure-based model that also embeds a fixed site carrier permeation membrane has been developed for CO2 capture from a coal-fired power plant and three scenarios based on the different flow patterns, i.e., co-current, counter-current and crossflow, were analysed to determine the effect of the flow pattern in the membrane module. The main objective of the optimisation was to minimise the cost of capture. The counter-current flow pattern resulted in the lowest cost of capture as it resulted in the most energy-efficient process system. The co-current flow-based optimisation results in configuration result in an 18 % increase in cost compared to the counter-current flow pattern optimisation run due to a 29 % increase in energy consumption. The crossflow pattern optimisation results in a 9 % increase in the annualised cost of capture compared to the counter-current flow.

Abstract The performance of factorial designs is still limited due to some uncertainties that usually intensify process complexities, hence, the need for inter-platform auto-correlation analyses. In this study, the auto-correlation capabilities of factorial designs and General Algebraic Modeling System (GAMS) on the effects of some pertinent operating variables in wastewater treatment were compared. Individual and combined models were implemented in GAMS and solved with the trio of BARON, CPLEX and IPOPT solvers. It is revealed that adsorbent dosage had the highest effect on the process. It contributed the most effect toward obtaining the minimum silica and TDS contents of 13 mg/L and 814 mg/L, and 13.6 mg/L and 815 mg/L from factorial design and GAMS platforms, respectively. This indicates a concurrence between the results from the two platforms with percentage errors of 4.4% and 0.2% for silica and TDS, respectively. The effects of the mixing speed and contact time are negligible.

Increasing freshwater costs and environmental concerns have necessitated the adoption of strategies for reducing freshwater consumption and effluent water discharge in chemical processes. Regeneration technologies increase opportunities for water reuse and recycle, and nanofiltration has emerged as a competitive wastewater regeneration technology. However, the optimal design of nanofiltration networks has not been extensively investigated. This study presents a framework for the optimal design and synthesis of multicontaminant nanofiltration membrane regenerator networks for application in water minimization problems. Mathematical optimization technique is developed based on a superstructure containing all system components and streams, incorporating nanofiltration units, pumps, and energy recovery devices. A linear approach and the modified Spiegler-Kedem model are explored in modelling the nanofiltration, and the steric-hindrance pore model is used to characterize the membrane. The objective of the optimization is to simultaneously minimize the water consumption and the total annual cost of the network. Furthermore, the optimal size, configuration, membrane properties and operating conditions of the equipment are determined. The applicability of the model is illustrated using a case study of an integrated pulp and paper plant. It was found that detailed models with customized modules are more useful when compared to the linear “black box” approach and approaches using fixed module specifications. The customized, detailed design of the regenerator network increased freshwater savings by 24% when compared to a black-box model, 31% when compared to a detailed model with fixed module specifications and 41% when compared to a reuse-recycle system with no regeneration. Similarly, cost savings of 38, 35 and 36% respectively were obtained. A trade-off was noted between the energy costs and the other components of the objective function since more energy was required to facilitate the reduction of water consumption and capital requirements.

Energy recovery from waste materials is a herculean task in view of its impact on the environment. Waste materials are becoming increasingly cumbersome considering huge proportion of synthetic materials being used for product formation and developmental projects. The process of energy recovery from these wastes serve to reduce significant quantity that would not be naturally decomposed thereby declining their influence on the safe environment. While global fossil fuel energy is finite in nature, this process provides alternative sources of energy in an environmentally friendly manner. The treatment process of waste to energy has no doubt increase the vulnerability of environment to climate change, among other methods. Studies have shown that waste generated from urban areas globally will increase from about 3.5 million tonnes per day to 6.1 million tonnes per day by 2025. These increasing waste volumes will definitely require the application of sophisticated incinerators to evolve alternative energy that could be used for basic needs. In this paper, the authors access the environmental impact of waste-to-energy recovery taking into considering the existing approaches, as per waste volume and available incinerating plants. The paper also identifies various waste gases associated with incinerating plants which could compromise environment and increase biodiversity dislocation. All these concerns were x-rayed as part of the suggestions to improve material formation towards biodegradability. Taking into consideration how long synthetic materials would continue in industrial space, this paper proposes a countermeasure which could be useful to stabilize the existing energy recovery process while hoping for full adaptation of sustainable and eco-friendly green materials.

Global production of plastics hasincreased astronomically in the last five decades. This may not be unconnected with the rate of consumption of plastics owing to their increasing applications and good characteristics such as light weight, strength, durability, affordability, corrosion resistance and low production costs. Production of plastic materials accounts for 3 to 5% greenhouse gas (GHG) emissions globally. Reports from published works show that, as of 2015 alone, close to 6300 metric tonnes of synthetic plastic waste were generated, of which only 9% were recycled with 12% being incinerated, and a large proportion,79%,discardedin the natural environment. Further studies show that a sizeable proportion,12,000 metric tonnes, of plastic waste may annually find their way into the environment by 2050. The adoption of biodegradable materials to replace the conventional plastics has been proposed and implemented with varying environmental implications. In this paper, a sustainable approach to plastic wastes was examined, taking into consideration the emerging and developing world’s attitudes about plastic waste management. Also discussed in this paper is the projection of the plastic waste market with particular reference to United States and China as global players in the industry. The concluding part of this paper focuses on future trends in plastic innovation with the evolution of nanoscale materials, bio-refining and most importantly cradle-to-cradle packaging materials. It is expected that this paper will assist various bodies involved in plastic waste management for developing better and sustainable methods.