Wastewater Treatment of Contaminated Aqueous Leachate

Until recently the common perception, especially in the western world, was that water was an infinite resource. There has been, however, a dramatic increase in the usage and pollution of water and a corresponding need to conserve, treat and re-use the resource. Water quality and scarcity are major global concerns and within industrial societies the treatment of waste water and aqueous leachate is of particular significance. One process that has shown promise for enabling the re-use of waste water is Fenton’s Reagent; in particular when it is combined with electrochemistry. The aim of this research is to establish the viability of one such process, electrochemical peroxidation (ECP), and to trial this in an applied setting. The study presents a review of the literature of electrochemistry for waste water treatment with an emphasis on techniques applying Fenton’s Reagent. This highlighted a limited progression from laboratory experimentation to on site application and coincided with a policy environment that had increasingly stringent quality requirements. Initial laboratory testing of ECP confirmed the potential of the process for treating aqueous leachate and highlighted the need to upscale and move from an experimental to an applied context. The findings from the laboratory informed the design and construction of a pilot plant that was installed and evaluated through two case studies. The first of these treated a range of waste waters and aqueous leachates to establish whether the system could be successfully up-scaled. The second case focused on aqueous leachate and the ability of the process to meet the required quality levels. The first case supported the laboratory studies through the achievement of reduced COD levels for the variety of waste waters trialled. The second study reinforced the potential of the ECP process for treating aqueous leachate however it also highlighted the need for additional equipment (e.g. iron filters, power supply modifications) to meet quality levels, Discharge Consent, for the site. A provisional cost analysis of the process shows that it was comparable with current treatment practices for the site (tanking off site) however the cost of hydrogen peroxide, a key component of Fenton’s Reagent, is shown to be the determining factor. This thesis is not experimental in the sense that it is a laboratory based, and iterative, process for testing the fundamental chemistry underlying electrochemical peroxidation; rather the main contribution of the study lies in designing, developing and evaluating the practical potential of this technology to be scaled up and applied in a range of working environments (e.g. landfill, composting, chemical treatment plants).

Name dc:type.qualificationname

PhD

Level dc:type.qualificationlevel

Doctoral

Grantor dc:publisher.institution

De Montfort University

Year dc:date.issued

2016

Author dc:creator

• Paton, Ian

Licence

• https://dora.dmu.ac.uk/bitstreams/0a2e394d-fb02-478a-ba5d-3f4960360112/download