NUTRIENTS REMOVAL FROM PARTIALLY TREATED WASTEWATER USING SOIL AQUIFER TREATMENT SYSTEM

Water reclamation through the use of soil aquifer treatment (SAT) is a sustainable water management technique with high potential for application in many regions worldwide. However, the fate of contaminants of emerging concern (CECs) during the infiltration of treated wastewater during SAT is still a matter of research. This study investigates the removal capacity of 27 CECs during SAT by means of infiltration experiments into a 6 m soil column. Additionally, the influence of the hydraulic operation of SAT systems on the removal of CECs is investigated by changing the wetting and drying cycle lengths. Sixteen out of 27 CECs are efficiently removed during SAT under various operational modes, e.g., bezafibrate, diclofenac and valsartan. For six substances (4-methylbenzotriazole, amidotrizoic acid, benzotriazole, candesartan, hydrochlorothiazide and sulfamethoxazole), removal increased with longer drying times. Removal of amidotrizoic acid and benzotriazole increased by 85% when the drying cycle was changed from 100 to 444 min. For candesartan and hydrochlorothiazide, removal improved by 35%, and for 4-methylbenzotriazole and sulfamethoxazole, by 57% and 39%, respectively. Thus, enhanced aeration of the vadose soil zone through prolonged drying times can be a suitable technique to increase the removal of CECs during SAT.

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Controlled field studies on soil aquifer treatment in a constructed coastal sandfill

Water Science & Technology ◽

10.2166/wst.2009.408 ◽

2009 ◽

Vol 60 (5) ◽

pp. 1283-1293 ◽

Cited By ~ 2

Author(s):

Lloyd H. C. Chua ◽

Melvin C. M. Leong ◽

Edmond Y. M. Lo ◽

Martin Reinhard ◽

Alexander P. Robertson ◽

...

Keyword(s):

Ultra Violet ◽

Field Studies ◽

Treated Wastewater ◽

Soil Aquifer Treatment ◽

Interstitial Oxygen ◽

Reclaimed Land ◽

Phreatic Surface ◽

Infiltration Rates ◽

Marine Sand ◽

Doc Concentration

A controlled artificial recharge experiment was conducted to investigate the effect of soil aquifer treatment during percolation of secondary and tertiary (ultrafiltered) treated wastewater through the shallow vadoze zone of a newly constructed coastal sandfill. The sandfill is a reclaimed land constructed from marine sand dredged from the seabed. To obtain 1-D flow, a stainless steel column was driven to a depth of 2.5 m, penetrating the phreatic surface. Wastewater was percolated through the column under fully-saturated and unsaturated conditions. Infiltration rates, dissolved organic carbon (DOC) and ultra-violet absorption (UVA) were monitored. The wastewaters were recharged at similar infiltration rates of approximately 5.5 m/day and 3.5 m/day under fully-saturated and unsaturated conditions, respectively. In both cases, clogging occurred 40 days after the start of recharge, under saturated conditions. For secondary treated wastewater, DOC concentration (mg/l) reduced by 28% and 13% under unsaturated and saturated conditions, respectively. The corresponding UVA reduction was 19.4% and 14.1%. Similar reductions in DOC were observed for the tertiary treated wastewater; however, the reduction in UVA was higher; 28% and 22% under unsaturated and saturated conditions, respectively. On an mass removal (mg/m2 DOC) basis, DOC reduction appeared to be more significant under unsaturated conditions. This is attributed to the presence of interstitial oxygen.

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Comparison of Organic Matter Removal from Synthetic and Real Wastewater in a Laboratory-Scale Soil Aquifer Treatment System

Water Air & Soil Pollution ◽

10.1007/s11270-013-1467-7 ◽

2013 ◽

Vol 224 (3) ◽

Cited By ~ 16

Author(s):

Mesut Ak ◽

Orhan Gunduz

Keyword(s):

Organic Matter ◽

Laboratory Scale ◽

Treatment System ◽

Soil Aquifer Treatment ◽

Organic Matter Removal ◽

Real Wastewater

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Oxidizer Demand in the Unsaturated Zone of a Surface-Spreading Soil Aquifer Treatment System

Vadose Zone Journal ◽

10.2136/vzj2015.03.0047 ◽

2015 ◽

Vol 14 (11) ◽

pp. vzj2015.03.0047 ◽

Cited By ~ 7

Author(s):

Roy Elkayam ◽

Alex Sopliniak ◽

Guy Gasser ◽

Irene Pankratov ◽

Ovadia Lev

Keyword(s):

Unsaturated Zone ◽

Treatment System ◽

Soil Aquifer Treatment ◽

Surface Spreading

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Evaluation of the efficiency of a gray water treatment system based on aeration and filtration

Journal of Water Reuse and Desalination ◽

10.2166/wrd.2021.084 ◽

2021 ◽

Author(s):

Maziar Kabiri ◽

Abolfazl Akbarpour ◽

Mohammad Akbari

Keyword(s):

Water Treatment ◽

Surface Water ◽

Total Coliform ◽

Treatment System ◽

Treated Wastewater ◽

Ultraviolet Disinfection ◽

Water Treatment System ◽

Gray Water ◽

Series Of Experiments ◽

Disinfection Unit

Abstract Gray water is a great resource for replacing fresh water to be used in standardized usages. The use of treated gray water reduces water consumption and the entry of pollutants into the environment. However, if left untreated, it can be dangerous. The present study examines the efficiency of a gray water treatment system consisting of primary filter, aeration, secondary filter and ultraviolet disinfection unit. After examining the characteristics of gray water, the efficiency of this system was analyzed to remove the pH, TSS, BOD, COD, ABS and total coliform parameters. Then, the gray water treated through this system was compared with the environmental standard of Iran. The pH of the treated gray water was 7.5–7.6. The efficiency of this system for removing the BOD and COD parameters was 98–100 and 76–100%, respectively. This system had an efficiency of 96–97% to eliminate the ABS parameter. Also, this system was able to eliminate total coliform with 100% efficiency. Results showed that in the three series of experiments performed on this system, according to the Iranian standard, the treated wastewater is suitable for irrigation and agricultural uses. However, this system could not be licensed for the COD parameter regarding the discharge to surface water and absorbent wells.

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The Effect of Soil Tillage Equipment on the Recharge Capacity of Infiltration Ponds

Water ◽

10.3390/w12020541 ◽

2020 ◽

Vol 12 (2) ◽

pp. 541 ◽

Cited By ~ 2

Author(s):

Ido Negev ◽

Tamir Shechter ◽

Lilach Shtrasler ◽

Hadar Rozenbach ◽

Avri Livne

Keyword(s):

Soil Compaction ◽

Soil Layer ◽

Infiltration Rate ◽

Treated Wastewater ◽

Soil Tillage ◽

Soil Aquifer Treatment ◽

Shallow Layer ◽

Reclamation Project ◽

Sandy Aquifer ◽

Micro Topography

The Dan Region Reclamation Project (Shafdan) reclaims ~125 millions of cubic meters per year (Mm3/year) of treated wastewater from the Tel Aviv Metropolitan area. Following secondary treatment, the effluent is recharged into a sandy aquifer for soil aquifer treatment (SAT). Over the past three years, a decrease in recharge capacity was noticed. Several operational causes were considered including reservations regarding the tillage procedure of recharge ponds. Tillage of the recharge ponds facilitates aeration, breaking surface crusts and the removal of vegetation. The procedure includes deep (40–60 cm) plowing and shallow (10–20 cm) sweep-knives (SK) cultivator or discus. In this research, the existing tillage equipment was compared to a new equipment, which includes a deep subsoiler and a chisel-knives (CK) cultivator. The effects of each tool on the infiltration rate (IR), recharge capacity, and soil compaction were examined. The results suggest a significant improvement in the recharge capacity, up to 95% and 15% on average following subsoiler and CK cultivator treatments, respectively, with respect to the existing plowing treatment. In addition, the depth of the compacted soil layer increased from ~30 to ~55 cm after subsoiler treatment. It seems that this shallow layer, developed under an improper tillage regime, played a major role in the reduction of the recharge capacity. Essential understanding of other operational factors such as drying periods, preparation of the field, and soil micro-topography was also achieved.

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