Retrieving back plastic wastes for conversion to value added petrochemicals: opportunities, challenges and outlooks

Plastic production and its unplanned management and disposal, has been shown to pollute terrestrial, aquatic, and atmospheric environments. Petroleum-derived plastics do not decompose and tend to persist in the surrounding environment for longer time. Plastics can be ingested and accumulate into the tissues of both terrestrial and aquatic animals, which can impede their growth and development. Petrochemicals are the primary feedstocks for the manufacture of plastics. The plastic wastes can be retrieved back for conversion to value added petrochemicals including aromatic char, hydrogen, synthesis gas, and bio-crude oil using various technologies including thermochemical, catalytic conversion and chemolysis. This review focusses on technologies, opportunities, challenges and outlooks of retrieving back plastic wastes for conversion to value added petrochemicals. The review also explores both the technical and management approaches for conversion of plastic wastes to petrochemicals in regard to commercial feasibility, and economic and environmental sustainability. Further, this review work provides a detailed discussion on opportunities and challenges associated with recent thermochemical and catalytic conversion technologies adopted for retrieving plastic waste to fuels and chemicals. The review also recommends prospects for future research to improve the processes and cost-efficiency of promising technologies for conversion of plastic wastes to petrochemicals. It is envisioned that this review would overcomes the knowledge gaps on conversion technologies and further contribute in emerging sustainable approaches for exploiting plastic wastes for value-added products

Real time model predictive control of inverters and linear motor drive

144 p.This thesis addresses the control problems in linear motion system and parallel connected inverters system. Model Predictive Control (MPC) technique has been investigated to improve the control performance of inverters and linear motor drive. Based on the characteristics of the applications, suitable control structure and techniques are proposed and developed to solve specific problems.DOCTOR OF PHILOSOPHY (EEE

Modeling the electrical effects of metal dishing due to CMP for on-chip interconnect optimization

A dishing model is developed to investigate the electrical effects of metal dishing in the damascene process, based on experimental data and physical analysis. A metric for dishing, the Dishing Radius, has been defined. A study utilizing this model shows that the impact of dishing on performance can be mitigated at both the process and design stages. More specifically, process improvement is most effective when the dishing radius is less than 50 Mm. During design, dishing effects can be suppressed by uniformly splitting a wide line into several narrower lines; the most beneficial number of line-splitting is between two and four from both efficiency and performance considerations