Effect of Different Filtration Materials on Removal of Selected Micropollutants from Synthetic Greywater

Fatma Öykü Cömez

Master's thesis

Abstract:

There is a risk of environmental damage if untreated greywater is used directly. Mainly due to the growing use of pharmaceuticals and personal care products (PPCP), which can have an ecotoxic effect and thus be harmful to biota. Research into the removal of these pollutants is therefore essential for the safe reuse of greywater, which is a promising solution to water shortage. The main goal of this study is to identify the role of different filter materials on the efficiency of removing pollutants from synthetic greywater (SGW). This study is based on a laboratory experiment which is testing different filtration materials for 5 weeks by a column test. The columns were filled with weekly prepared SGW and samples were measured daily after 20 resp. 72 (weekend) hours contact time. Selected micro-pollutants were PPCPs (Diclofenac, Benzotriazole, DEET, Methylparaben, Caffeine), anionic surfactants, total nitrogen (TN), total organic carbon (TOC), and trace elements (Boron, Copper, Zinc, and Nickel). The filtration bed of the columns was designed in three layers; first 3.3 cm of gravel (4-8 mm), then 13 cm of sand (0-4 mm). The top layer (28.6 cm thick) contained technogenic soil (compost, sand and soil) and an additive. Each group contained only one of the additives (wood chips, mycorrhiza, crushed bricks, crushed limestone and biochar 5 or 10% of the volume of the top layer). There were 5 replications in each treatment group. The results indicated that except benzotriazole, the other PPCP’s and anionic surfactants might undergo sorption and biodegradation. Among the biofilter materials, only biochar filters achieved high removal efficiency for all organic compounds including benzotriazole. The metal removal efficiency of all biofilter materials was more than 90%. However, boron was found to be leached. Finally, the best results of sorption and filtration efficiency was observed for 5 % biochar filters (PPCP and metal removal efficiency) and it was higher than 90 % (excluding boron). Given the results, biochar can be a potentially effective and inexpensive solution for greywater treatment, PPCP and heavy metal removal.

Keywords

Infiltration, Filtration Materials, Synthetic Greywater, Column Test, Removal Efficiency, Diclofenac, Benzotriazole, DEET, Methylparaben, Caffeine

Language used: English

Date on which the thesis was submitted / produced: 31. 3. 2021

Thesis defence

• Supervisor: prof. RNDr. Dana Komínková, Ph.D.

Czech University of Life Sciences Prague

Faculty of Environmental Sciences

Master programme / field:
Landscape Engineering / Landscape Planning