Pyrolytic urban mining of waste printed circuit boards: an enviro-economic analysis.

E-waste, a global environmental concern resulting from supply chain inefficiency, also offers the opportunity to recover valuable materials, including general and rare earth metals. Waste printed circuit boards (WPCBs) are integral components of e-waste that contains substantial amounts of precious metals, making them a valuable waste category. Pyrolysis has emerged as a promising method for material recovery from WPCBs. Hence, pyrolytic urban mining of WPCBs offers an excellent avenue for resource recovery, redirecting valuable materials back into the supply chain. Under the current study, experimental investigation has been conducted to explore the recovery of materials from WPCBs through pyrolysis followed by process simulation, economic analysis, and life cycle assessment (LCA). An Aspen Plus simulation was conducted to model the pyrolysis of WPCBs and subsequent product recovery using a non-equilibrium kinetic model, which represents a unique approach in this study. Another distinct aspect is the comprehensive assessment of environmental and economic sustainability. The economic analysis has been carried out using Aspen economic analyzer whereas the LCA of WPCB pyrolysis has been conducted using the SimaPro software. The experimental investigation reveals yield of solid residues are about 75-84 wt.%, liquid yields of 6-13 wt.%, and gas yields of 4-21 wt.%, which is in well agreement with the Aspen Plus simulation results. The economic analysis for an e-waste pyrolysis plant with an annual feed rate of 2000 t reveals that the total capital cost of a pyrolysis plant is nearly $51.3 million, whereas the total equipment cost is nearly $2.7 million and the total operating cost is nearly $25.6 million. The desired rate of return is 20% per year and the payback period is 6 years with a profitability index of 1.25. From the LCA, the major impact categories are global warming, fossil resource scarcity, ozone formation in human health, ozone formation in terrestrial ecosystems, fine particulate matter formation, and water consumption. The findings of this study can serve as a guideline for e-waste recyclers, researchers, and decision-makers in establishing circular economy.

Resource Resurgence from COVID-19 Waste via Pyrolysis: a Circular Economy Approach.

Since the end of 2019, COVID-19 pandemic has affected 220 countries and currently majority of the world is facing the wrath of the second wave. One of the outcomes of the ongoing pandemic is the generation of huge amount of solid polymeric "COVID-waste" comprising medical waste, personal protective equipment (PPE) waste, packaging waste, and other household waste with potential infectious components residing on it. Thermochemical route is the preferred treatment and effective way of disposal of such infectious polymeric waste. Typically, incineration is employed to ensure complete destruction of the pathogens which is not a resource-efficient method. Pyrolysis is a sustainable alternative which can handle the present COVID-waste stream in short-term and long-term yielding valuable fuel and material products. Recently published literature in this avenue have clearly shown the versatility of this technology in efficiently handling both mono and mixed stream of polymers. Based on facts, we propose a resource resurgence framework that utilizes pyrolysis as the core conversion route for effectively handling COVID-waste streams. Our framework suggests how these plants can be operational and helpful in generation of revenue in post-pandemic times as well. We expect that the conscientious adoption of pyrolysis will certainly lead us towards a circular economy paradigm.

Design of a multivariable stimulus for Emotional-Learning based control of a 2-DOF laboratory helicopter.

Emotional-Learning based controllers are becoming increasingly popular due to their non-parametric and flexible design approach. However, most of the existing Emotional-Learning based control strategies are designed specifically for individual loops and are not suitable for superior performance in a strongly coupled MIMO system. In this technical note, a multi-variable Emotional-Learning based strategy for trajectory tracking in a strongly coupled MIMO system is proposed. This strategy incorporates an improved stimulus design that deals with tracking, regulation, disturbance-rejection and coupling effects in a systematic way. The strategy also addresses the deleterious effects of mechanical resonance associated with flexible structures from the perspective of stimulus design. The proposed strategy is validated through simulations and hardware based experiments on a 2-DOF laboratory helicopter. Effectiveness of the proposed strategy is illustrated through comparisons with an optimized multi-variable LQG controller.

Supply chain analysis of e-waste processing plants in developing countries.

e-Waste is generated at the staggering rate of 6.1 kg per person. In 2016, 44.7 million tonnes was generated globally, and the amount is estimated to reach 52 million tonnes annually by 2021. The management of this huge quantity of e-waste is a major problem across the world, primarily in developing countries. An effective e-waste management system is linked to the sustainability of e-waste processing plants, and currently it is plagued with different supply chain network (SCN) issues. To address the issues and challenges of SCN, there is a need to prioritize and address the constructs. The study thus combines two multiple criteria decision making (MCDM) tools, the analytical hierarchy process (AHP) and quality function deployment, to prioritize the constructs identified from literature and supported by field studies. The house of quality (HOQ) has been used for analyzing different stakeholders' requirements. The degree of importance for HOQ-1 has been derived using the AHP tool. The study revealed the most intriguing issues and challenges of e-waste processing plants considering the requirements of different stakeholders. The results showed formal collection, storage, semi-informal collection, and e-waste quality to be the major issues of processing plants. The findings obtained from MCDM analysis have been validated though two case studies in India and China. If the results obtained are applied to the existing e-waste SCN, a holistic e-waste management system can be achieved for developing countries.

Waste electrical and electronic equipment management and Basel Convention compliance in Brazil, Russia, India, China and South Africa (BRICS) nations.

Brazil, Russia, India, China and South Africa (BRICS) nations account for one-quarter of the world's land area, having more than 40% of the world's population, and only one-quarter of the world gross national income. Hence the study and review of waste electrical and electronic equipment management systems in BRICS nations is of relevance. It has been observed from the literature that there are studies available comparing two or three country's waste electrical and electronic equipment status, while the study encompassing the BRICS nations considering in a single framework is scant. The purpose of this study is to analyse the existing waste electrical and electronic equipment management systems and status of compliance to Basel convention in the BRICS nations, noting possible lessons from matured systems, such as those in the European Union EU) and USA. The study introduced a novel framework for a waste electrical and electronic equipment management system that may be adopted in BRICS nations and revealed that BRICS countries have many similar types of challenges. The study also identified some significant gaps with respect to the management systems and trans-boundary movement of waste electrical and electronic equipment, which may attract researchers for further research.