Browsing by Author "Sakar, Hacer"

Now showing 1 - 3 of 3
  • Thumbnail Image
    ItemOpen Access
    Gaps in regulation and policies on the application of green technologies at household level in the United Kingdom
    (MDPI, 2022-03-29) Bortone, Imma; Sakar, Hacer; Soares, Ana
    ited Kingdom (UK) government established a Ten-Point Plan and over GBP 5 billion to support Green-Tech to lay the foundations for a green industrial revolution and reduce emissions by 180 million tons of carbon dioxide equivalent (CO2e) by 2032. Households and buildings contribute around 40% of the UK’s total GHG emissions, which implies that key actions are needed in all areas around the building sector (Point 7). This study provides an overview and analysis of the existing regulation and standards in the UK building/household sector, to understand the current state-of-the-art and identify gaps preventing Green-Tech wider implementation and use. Discrepancies in regulation and standards were identified. Given that households bring together and adhere to numerous standards and regulations, the analysis highlighted that it is critical to formulate relevant actions starting from the individuals with engagement and information. Complete and clear guidelines addressing environmental awareness, the performance and economical convenience of Green-Tech implementation and related regulations, are required to come to a consensus on the best way to move forward to achieve sustainability and NET-ZERO targets.
  • Thumbnail Image
    ItemOpen Access
    Investigation of pre‑treatment techniques to improve membrane performance in real textile wastewater treatment
    (Springer, 2022-03-22) Özgün, H.; Sakar, Hacer; Ağtaş, M.; Koyuncu, İ.
    Membrane technology has a significant role in textile wastewater treatment considering the modular design of the membrane processes that enables to conceive a complete treatment scheme. The study presents a comparative study of microfiltration (MF) (0.2 µm and 0.05 µm), ultrafiltration (UF), ozonation (0.1, 0.2 g/L ozone), ultraviolet (UV) irradiation and titanium dioxide (TiO2) (0.05, 0.15, 0.3, 0.5 g/L TiO2) and zeolite adsorption (125, 250, 500 mL/min flow rates) processes as pre-treatment prior to nanofiltration (NF) and reverse osmosis (RO) membranes for the treatment of real textile washing wastewater (WW). Experiments demonstrated that the applied pre-treatment methods enhanced the flux performance of NF270 and RO membranes except zeolite adsorption. By evaluation of all pre-treatment alternatives, it was seen that the best chemical oxygen demand (COD) removal efficiency (41%) was achieved with MF0.05 membrane. The highest conductivity removal efficiencies were obtained by UV/TiO2 application and with ozonation process the colour of the wastewater was removed at a performance of 80.5%, that was the highest among all pre-treatment applications. Based on the permeate flux and quality, the best pre-treatment method was selected as MF membrane with a pore size of 0.05 µm. Best conductivity removal efficiency was obtained by MF0.05 + XLE membrane combination at 93.6%. Also, considerably high COD removals were achieved with pre-treated NF and RO combinations together with a significant colour elimination (> 98%). In this study, it is aimed to create an efficient system that can be applied in real textile wastewater treatment by creating a combined treatment process.
  • Thumbnail Image
    ItemOpen Access
    Removal of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) by coagulation: influence of coagulant and dosing conditions
    (Elsevier, 2025-03-01) Wang, Pin; An, Guangyu; Carra, Irene; Hassard, Francis; Campo Moreno, Pablo; Sakar, Hacer; Jodkowska, Monika; Wang, Dongsheng; Jefferson, Bruce; Chu, Wenhai; Jarvis, Peter
    Per- and polyfluoroalkyl substances (PFAS) pose significant risks to the environment and human health. Perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) are two of the most frequently detected PFAS in the environment. In most surface water drinking water treatment works (WTW), coagulation is the first processes exposed to a range of contaminants, including PFAS. While not designed to be a process for removal of micropollutants, it is important to understand the fate of PFAS in coagulation processes, intended or otherwise, to determine whether water treatment sludge can be a significant sink for this group of micropollutants. This work advances understanding of PFAS removal in coagulation processes by comparing the removal of PFOA and PFOS by four metal coagulants (Zr, Zn, Fe, and Al) from real water matrices. The coagulant performance followed the order Al > Fe > Zr > Zn. Al was taken forward for further evaluation, with significant removal of PFAS (>15 % for PFOA and > 30 % for PFOS) being observed when the pH<5.5 and the dose was > 5 mg Al·L-1. The adsorption of PFOA and PFOS onto flocs through hydrophobic interaction was the primary removal route. The impacts of background matrix on the mechanisms of coagulation for PFAS were explored using five organic compounds. Macromolecular organic compounds contributed to an increase in removal due to the sorption of PFAS and subsequent removal of the organic-PFAS aggregate during coagulation. Low molecular weight organic matter inhibited the removal of PFAS due to the ineffective removal of these compounds during coagulation.