Evaluation of irrigation suitability potential of brewery effluent post treated in a pilot horizontal subsurface flow constructed wetland system: implications for sustainable urban agriculture

Abstract Background Agro-industrial wastewaters in Ethiopia cause severe environmental pollution problems. Research evidence showed that anaerobic reactors are good options for the treatment of these wastewaters. But, their final effluent does not meet the discharge standards. Conversely, a series stage horizontal subsurface flow constructed wetland (HSSFCW) system is encouraging for the polishing of anaerobic reactor effluents. However, its treatment efficiency is dependent on hydraulic residence time (HRT). Cyperus alternifolius and Typha latifolia-based wastewater treatment showed good removal efficiencies individually. However, data on their combined treatment effectiveness is negligible. Therefore, this study assesses HRT influences on the treatment effectiveness of a two-stage HSSFCW system planted with these two macrophytes for the polishing of anaerobic reactor brewery effluent. A series connected two-stage HSSFCW unit planted with Cyperus alternifolius and Typha latifolia was built to treat Kombolcha brewery anaerobic reactor effluent. Then, the macrophytes were endorsed to grow with continuous application of diluted brewery effluent from a reservoir tank using gravity force. After dense stand formation, the experiment was initiated to determine the influence of HRTs on the removal efficiency of a complete wetland system. The system was operated sequentially by supplying fixed influent inflow rates of 2791, 1395, 930, 698, and 558 L day−1, respectively, for 1, 2, 3, 4, and 5 days HRT. Both the influent and effluent of the two-stage HSSFCW system were analyzed following common procedures for main brewery pollutants. Result Results showed that as HRT increased from 1 to 5 days, the effluent pH and temperature were decreased along with enhanced pollutant removals ranging from 47.8–87.2%, 29.2–90.1%, 32.9–77.7%, 16.8–75.4%, and 18.4–76.8% with decreased influent mass loading rates ranging from 26.4–2.1, 64.5–7.3, 11.5–0.8, 5–0.6, and 3.8–0.4 gm−2 day−1, respectively, for total suspended solids, chemical oxygen demand, total nitrogen, total phosphorous and orthophosphate. However, better and steadier pollutant removals were achieved at higher HRTs. Conclusion For better nutrient removals, the 4 and 5 days HRT can serve as a good benchmark.

Download Full-text

Construction and maintenance cost analyzing of constructed wetland systems

Water Practice & Technology ◽

10.2166/wpt.2011.043 ◽

2011 ◽

Vol 6 (3) ◽

Cited By ~ 9

Author(s):

K. Gunes ◽

B. Tuncsiper ◽

F. Masi ◽

S. Ayaz ◽

D. Leszczynska ◽

...

Keyword(s):

Wastewater Treatment ◽

Constructed Wetlands ◽

Constructed Wetland ◽

Rural Areas ◽

Subsurface Flow ◽

Maintenance Cost ◽

Operational Costs ◽

Subsurface Flow Constructed Wetland ◽

Wetland System ◽

Horizontal Subsurface Flow

Nowadays, use of constructed wetlands for wastewater treatment especially in rural areas has become increasingly preferable. The most important reason behind this fact is its relatively low investment cost over other treatment options depending on economical conditions of the country. Nonetheless, due to lower operational costs of constructed wetlands than other conventional wastewater treatment systems, investment costs could be regarded secondary as of importance. Investment costs could show differences even at regional scale in a country. Choosing a constructed wetland system among “Subsurface Horizontal Flow”, “Subsurface Vertical Flow” or “Free Water Surface Flow”; or designing a hybrid system using concurrent systems plays important role when defining costs of the constructed wetland systems. Due to increasing interest for constructed wetlands since 2003, so many constructed wetland systems have been built in rural parts of Turkey and most of these systems have been designed as horizontal subsurface flow constructed wetland system. As a fact, the cost of horizontal subsurface flow constructed wetlands is comparatively higher than other wetland systems. When different applications in the world are examined, it is observed that mostly horizontal subsurface flow constructed wetland systems are preferred in rural areas. According to the studies within the extent of this work, different constructed wetland types which are built in different regions of Turkey and their expected and realized costs are analyzed and compared with other countries. Moreover, operational costs have been calculated. Consequently, a work to be taken as reference for further scientific studies has been prepared with presented wetland analyses which could be used by especially decision makers and researchers.

Download Full-text

Nitrogen removal in a combined vertical and horizontal subsurface-flow constructed wetland system

Desalination ◽

10.1016/j.desal.2009.03.003 ◽

2009 ◽

Vol 247 (1-3) ◽

pp. 466-475 ◽

Cited By ~ 51

Author(s):

B. Tunçsiper

Keyword(s):

Nitrogen Removal ◽

Constructed Wetland ◽

Subsurface Flow ◽

Subsurface Flow Constructed Wetland ◽

Wetland System ◽

Horizontal Subsurface Flow

Download Full-text

Coliform removal in a constructed wetland system used in post-swine effluent treatment

Ambiente e Agua - An Interdisciplinary Journal of Applied Science ◽

10.4136/ambi-agua.2402 ◽

2019 ◽

Vol 14 (5) ◽

pp. 1 ◽

Cited By ~ 1

Author(s):

Fabiana De Amorim ◽

Jaíza Ribeiro Mota e Silva ◽

Ronaldo Fia ◽

Luiz Fernando Coutinho de Oliveira ◽

Cláudio Milton Montenegro Campos

Keyword(s):

Constructed Wetland ◽

Subsurface Flow ◽

Experimental System ◽

Effluent Treatment ◽

Swine Wastewater ◽

Subsurface Flow Constructed Wetland ◽

In Series ◽

Wetland System ◽

Horizontal Subsurface Flow ◽

Stage 1

This study evaluated the efficiency of a constructed wetland system (CWS) in removing total coliforms (TC) and thermotolerant coliforms (ThC) of swine wastewater, as a complementary treatment to an anaerobic system. At Stage 1, the experimental system was combined using a vertical flow constructed wetland system (VFCWS) cultivated with Tifton 85 grass in series with a horizontal subsurface flow constructed wetland system (HFCWS1) cultivated with Taboa. In HFCWS1, the hydraulic detention times (HDT) were 4.7, 3.1 and 2.3 days and the surface application rates (SAR) were 294, 319 and 397 kg ha-1 d-1 of COD, in Phases I, II and III, respectively. At Stage 2, the experimental system was combined using a horizontal subsurface flow constructed wetland system (HFCWS2) cultivated with Tifton 85 grass, HDT were 6.1, 2.0 and 0.5 days and the SAR were 850, 656 and 6.34 kg ha-1 d-1 of COD, in Phases I, II and III, respectively. In Stage 1, it was verified that the VFCWS was more efficient in coliform removal when compared to HFCWS1. When only HFCWS were compared, coliform removal in Stage 1 was between 1 and 2 log units in HFCWS1. In the stage 2, the HFCWS2 was more limited, with the highest removal efficiencies during Phase I of 1.6 and 0.8 log units for TC and ThC, respectively. In general, the association resulted in efficiencies that ranged from 96.4 to 99.0% for TC, 94.2 and 97.6% for ThC, equivalent to the average removal of 1.2 to 2 log units, considered satisfactory.

Download Full-text