Use of broken brick to enhance the removal of nutrients in subsurface flow constructed wetlands receiving hospital wastewater

Abstract

Eight horizontal subsurface flow pilot scale artificial wetlands were constructed to evaluate the effectiveness of broken brick to remove nutrients from hospital wastewater. The average total suspended solids (TSS), 5-day biochemical oxygen demand (BOD5), chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN), NH4-N, NO3-N, and phosphate percent removal efficiency of constructed wetlands were, respectively, 93.2%, 90.4%, 83.7%, 64%, 64.3%, 52.1% and 56.1% in the dry season and 89.7%, 85.8%, 82.9%, 66%, 62.7%, 56.1% and 59.5% in the rainy season. Broken brick bed wetlands provide better removal efficiency of TKN, ammonia, nitrate, and phosphate with an average removal rate of 73%, 71.3%, 79.6% and 77.1% in the dry season and 74.7%, 70.7%, 70.9% and 73.6% in the rainy season, respectively, and it provides better adsorption sites for ammonium, nitrate, and phosphate. Typha with the broken brick bed significantly improved (P < 0.05) the treatment performance of the constructed wetland systems for the removal of ammonia, nitrate, and phosphate. The seasonal variation could not significantly influence the removal of all the pollutants, but better performance of nitrate and phosphate was achieved in a dry season. Use of locally available broken brick as a substrate media can increase the nutrient removal efficiency of wetlands at a cheaper cost when applied in full scale constructed wetlands.

A review of emerging organic contaminants (EOCs), antibiotic resistant bacteria (ARB), and antibiotic resistance genes (ARGs) in the environment: Increasing removal with wetlands and reducing environmental impacts

“…Absolute abundances of ARB were reduced from the influent to the effluent by up to 93.2%. Dires et al (2018Dires et al ( , 2019) also highlighted the role of vegetation in CWs, as they observed that ARB removals were higher in planted CWs (81% -93%) than in unplanted wetlands (42% -74%). Plants do not seem to be directly involved in the removal efficiency of ARGs, but they are involved indirectly.…”

“…Higher relative surface area, micropores and Si-OH structures for chemical sorption and microbial attachment improve the removal of ARGs (Hu et al, 2012). Dires et al (2018Dires et al ( , 2019) evaluated the effectiveness of broken brick as filtering material in 8 HSSF-CWs (mesocosms scale) to remove nutrients and ARB from hospital wastewater in Ethiopia.…”

Towards Effective, Sustainable Solution for Hospital Wastewater Treatment to Cope with the Post-Pandemic Era

“…Dires et al [67] compared the nitrogen and P removal capabilities of planted (sugar cane) and non-planted CWs and discovered that planted wetlands had a greater capacity to eliminate nitrogen and P, which was probably due to the stimulation of the plant rhizosphere to produce more microbes. Through phytoremediation [68], plants remove contaminants such as antibiotics, heavy metals, and pathogens.…”

A review on hospital wastewater treatment: A special emphasis on occurrence and removal of pharmaceutically active compounds, resistant microorganisms, and SARS-CoV-2

“… M1, M2, M3A, M3B = 800 L/h, M4, M5 = 300 L/h M1, M2, M3A, M3B = 1.13 h, M4, M5 = 1.67 h Pilot-scale [113] Study 9 Denmark MBR followed by 450 mg/L of PAC 2.2 m 3 /day 35 days Pilot-scale [10] Study 10 Denmark MBR 2.2.m 3 /day 35 days Pilot-scale [10] Study 11 Ethiopia Waste Stabilization Ponds: 2 facultative ponds (667 m 2 ), 2 maturation ponds (401 m 2 , 396 m 2 ), and 1 fish pond (862 m 2 ) 29 days Full-scale [117] Study 12 Ethiopia 8 horizontal subsurface flow CWs (4 m length, 1.2 m width and 0.6 m depth) with gravel and broken brick media as substrate. 165.75 L/day 4 days Pilot-scale [12] , [97] Study 13 Finland Ultrafiltration followed by pulsed corona discharge (30 W was applied for 1 kWh /m 3 of pulse energy delivered) Pilot-scale [119] Study 14 Spain MBR (11 m 3 ) with 10 flat sheet (FS) chloral polyethylene membranes (0.8 m 2 each). Coarse bubble aeration was provided, MLSS- 8 g/L 100 L/h 50 h 30 days [100] Study 15 ...…”