A carregar...
Publicação
Wastewater and drinking water treatment by membrane processes: from laboratory to pilot-scale
| Nome: | Descrição: | Tamanho: | Formato: | |
|---|---|---|---|---|
| 6.65 MB | Adobe PDF |
Autores
Orientador(es)
Resumo(s)
The concern with water quality problems worldwide has led to the improvement of water/wastewater
treatment processes. In this PhD project, industrial water and drinking water treatments using
membrane processes were investigated in three different case studies. The main aim of these works
was the assessment, optimisation and validation of the process’s technologies for the respective case
studies. These studies included in a laboratory stage followed by a pilot-scale stage.
The first case study contemplates residual water from a rubber industry presenting high chemical
oxygen demand (COD). The impact of retrofitting of the existent wastewater treatment process with
the replacement of the previously used evaporator with an integrate system (nanofiltration+
evaporator), was evaluated. Two modes of operation were considered, batch and continuous, depending
on the daily flowrate of water to be treated in this industry.
The second case study addresses surface water treatment, for production of drinking water with a high
chemical and microbiological quality, required by the current legislation. The research was focused on
the validation of a multibarrier system incorporating nanofiltration and UV photolysis performed at
three different locations of the surface drinking water production line.
The third case study focuses on a novel treatment process dealing with groundwater contaminated by
arsenic (in its inorganic arsenate form) with the purpose to be applied in rural areas located far from
centralised drinking water supply infrastructures. It has been a challenge worldwide to treat arsenic
contaminated drinking water in order to meet the current strict regulation standard for As. In this
research, an ion exchange membrane process, integrating Donnan dialysis with precipitation of this
target pollutant was proposed. This work explored the feasibility of arsenic removal from water streams
containing sulphate, which strongly competes with arsenate and is preferentially transported through
strong-base anion-exchange membranes. Subsequently, the optimisation of arsenic removal from
drinking water by the process proposed was performed by using a response surface methodology
(RSM).
A systematic analysis of the three case studies was carried out and is presented in this thesis in order
to provide a deeper insight into the treatment processes studied (theoretical and practical aspects),
which makes the proposed solutions also applicable to other water/wastewater treatment cases, facing
similar challenges.
Descrição
Palavras-chave
Water Treatment Nanofiltration Ion-Exchange Membrane Donnan dialysis Drinking water Wastewater