Performance of slow rate systems for treatment of domestic wastewater

2007 ◽  
Vol 55 (1-2) ◽  
pp. 139-147 ◽  
Author(s):  
V.E. Tzanakakis ◽  
N.V. Paranychianakis ◽  
A.N. Angelakis
Keyword(s):  
Soil Solution ◽  
Plant Species ◽  
Slow Rate ◽  
Soil Depth ◽  
Domestic Wastewater ◽  
Septic Tank ◽  
Treatment Efficiency ◽  
Application Rates ◽  
N Removal ◽  
Acacia Cyanophylla

The performance of slow rate (SR) systems in terms of treatment efficiency, environmental and health risks, and land sustainability was investigated over a three-year period in a rural community close to Iraklio, Greece. Four plant species (Acacia cyanophylla, Eucalyptus camandulensis, Populus nigra and Arundo donax) were used in order to investigate the role of vegetation in the treatment of wastewater and in biomass production. Wastewater effluent was pre-treated in a septic tank before its application to land. Applied hydraulic loading rates were based on crop water requirements which were determined separately for each plant species. The evaluation of treatment performance was accomplished by measuring COD, TKN, NH3-N, NO3-N, total and reactive P, TC and FC in soil solution samples taken at different depths (15, 30 and 60 cm). SR systems showed great potential for COD, TKN and NH4-N removal which reached 89, 90 and 94%, respectively at a depth of 15 cm. An outstanding removal was also observed for TC and FC which reached 99.99%. The concentration of both P and NO3-N in soil solution increased with the passage of time, but it was lower in winter. Despite the differences in the application rates among the SR systems planted with different plant species, the treatment efficiency was not affected. Moreover, increasing the soil depth from 15 to 60 cm had no effect on the treatment efficiency of the SR systems.

scholarly journals Nutrient removal from septic effluents as affected by soil thickness and texture

2006 ◽  
Vol 4 (2) ◽  
pp. 177-195 ◽  
Author(s):  
A. D. Karathanasis ◽  
T. G. Mueller ◽  
B. Boone ◽  
Y. L. Thompson
Keyword(s):  
Soil Depth ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Health Department ◽  
Separation Distance ◽  
Treatment Efficiency ◽  
Undisturbed Soil ◽  
Soil Thickness ◽  
Total N ◽  
Total P

This study evaluated the effectiveness of soils with different textures and thickness to treat BOD, N and P eluted from household septic effluent. The assessments were accomplished by leaching undisturbed soil monoliths of 30, 45 and 60 cm thickness and 25 cm in diameter, representing the four different textural groups and hydraulic loadings recommended by the Kentucky Health Department, with domestic wastewater effluent collected regularly from a household septic system. Effluent concentrations were monitored daily over a 15 d period for biochemical oxygen demand (BOD), total-N, NH4–N, NO3–N and total-P concentrations. The results of the study indicate an alarming frequency of failure to comply with EPA criteria for BOD, total-N and NH4–N concentrations when using a 30 cm vertical separation distance between the bottom of the drain field and a limiting soil interface. The treatment performance was particularly poor in coarse-textured soils, apparently due to insufficient reactive surface area. Although biomat development over time is expected to improve the treatment for some of these parameters, the high influent levels of BOD pose great concerns for surface and groundwater contamination during the early stages of operation. Fine-textured soils generally provided better treatment efficiency and more consistent compliance with EPA standards for BOD, total-N, NH4–N and total-P, as well as greater nitrification/denitrification potential. Treatment efficiency and compliance usually improved with increasing soil depth, with the 60 cm thickness providing the most consistent performance and compliance with MDL requirements. Considering that increasing soil thickness requirements may be impractical in many marginal soils, complementary or alternative treatment technologies should be adopted to improve treatment efficiency and prevent further deterioration of the quality of water resources.

Wastewater treatment and biomass production by slow rate systems using different plant species

2003 ◽  
Vol 3 (4) ◽  
pp. 185-192 ◽  
Author(s):  
V.E. Tzanakakis ◽  
N.V. Paranychianakis ◽  
S. Kyritsis ◽  
A.N. Angelakis
Keyword(s):  
Wastewater Treatment ◽  
Rural Communities ◽  
Plant Species ◽  
Biomass Production ◽  
Slow Rate ◽  
Soil Depth ◽  
Appropriate Technology ◽  
Natural Treatment Systems ◽  
Poplar Trees ◽  
Natural Treatment

Natural treatment systems especially those based on land treatment, remain the only viable choice for wastewater treatment and reuse in small rural communities. In order to develop the appropriate technology required a slow rate (SR) systems were established at Skalani, a small village close to Iracklio, Greece. The SR systems were planted with four plant species eucalyptus, acacia, poplars and reeds to evaluate their effects on wastewater treatment and produced biomass. Systems performance were evaluated by monitoring BOD, COD, TSS, TKN, NH3-N, NO3-N, FC, and TC in soil solution and soil samples taken from the 15, 30 and 60 cm of the soil depth. The SR systems, displayed a good performance as regards COD BOD, TKN, NH3-N and bacteria removal (TC and FC). However, relatively increased values of NO3 were detected in 60 cm. In terms of plant species used, there were no significant differences in treatment efficiency among the four SR systems. Although, significant differences were observed in biomass production with acacia trees producing the greatest amount of biomass followed by reeds, while the lowest one produced by eucalyptous and poplar trees.

The Performance of the Rotating Disc System under the Tropical Conditions in Taiwan

1986 ◽  
Vol 18 (7-8) ◽  
pp. 177-183 ◽  
Author(s):  
Pak-Shing Cheung
Keyword(s):  
Pilot Scale ◽  
Septic Tank ◽  
Design Criteria ◽  
Organic Loading ◽  
Treatment Efficiency ◽  
Rotating Disc ◽  
Detention Time ◽  
Biological Sludge ◽  
N Removal ◽  
Tropical Conditions

In this investigation, the discharge from a septic tank and community wastewater were treated in a pilot scale rotating disc system (RDS) to evaluate the performance of this system under the tropical conditions in Taiwan, with the intention of developing design criteria useful for this region. It was found that by varying the organic loading to the system, different degrees of treatment could be obtained. Results of this study indicated that with an organic loading of 8-10 g B0D/(m2, d), 90% removal of BOD as well as NH4-N removal could be achieved. Ambient temperature was found to have no significant effect on the treatment efficiency, and the optimum hydraulic detention time was within 3 hours. Biological sludge production amounted to 0.6-0.8 kg/kg BOD removed.

scholarly journals Effect of soil depth and texture on fecal bacteria removal from septic effluents

2006 ◽  
Vol 4 (3) ◽  
pp. 395-404 ◽  
Author(s):  
A. D. Karathanasis ◽  
T. G. Mueller ◽  
B. Boone ◽  
Y. L. Thompson
Keyword(s):  
Environmental Protection Agency ◽  
Soil Depth ◽  
Domestic Wastewater ◽  
Health Department ◽  
Separation Distance ◽  
Fecal Bacteria ◽  
Vertical Separation ◽  
Treatment Efficiency ◽  
Undisturbed Soil ◽  
Improve Treatment

This study evaluated the effectiveness of soils with different texture and depth to treat fecal bacteria eluted from a house-hold septic effluent. The assessments were accomplished by leaching undisturbed soil monoliths of 30, 45, and 60 cm thickness and 25 cm in diameter, representing the four different textural groups and hydraulic loadings recommended by the Kentucky Health Department, with domestic wastewater effluent collected regularly from a house-hold septic system. Eluent concentrations were monitored daily over a 15 day period for fecal coliform and fecal streptococci concentrations. The results of the study indicate an alarming frequency of failure to comply with United States Environmental Protection Agency (USEPA) criteria for depth to groundwater, when using a 30 cm vertical separation distance between the bottom of the drain-field and a limiting soil interface. The treatment performance was especially poor in coarse-textured soils. Although biomat development over time is expected to improve treatment, the high influent levels of fecal bacteria pose great concerns for surface and groundwater contamination. Fine-textured soils generally provided better treatment efficiency and more consistent compliance with EPA standards. Treatment efficiency and compliance usually improved with increasing soil depth, with the 60 cm thickness providing the most consistent performance and compliance with maximum discharge limit (MDL) requirements. The findings of this study document a general inadequacy of the 30 cm vertical separation distance to provide effective treatment of septic effluents in Kentucky soils, particularly in coarse-textured soils. Considering that increasing the soil depth thickness may be impractical in many marginal soils, complementary or alternative treatment technologies should be adopted to improve treatment efficiency and prevent further deterioration of the quality of water resources.

scholarly journals Woven-Fiber Microfiltration (WFMF) and Ultraviolet Light Emitting Diodes (UV LEDs) for Treating Wastewater and Septic Tank Effluent

Water ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1564
Author(s):  
Sara Beck ◽  
Poonyanooch Suwan ◽  
Thusitha Rathnayeke ◽  
Thi Nguyen ◽  
Victor Huanambal-Sovero ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Light Emitting Diodes ◽  
Domestic Wastewater ◽  
Septic Tank ◽  
Uv Disinfection ◽  
Small Community ◽  
Photochemical Process ◽  
Light Emitting ◽  
Decentralized Wastewater Treatment ◽  
Septic Tank Effluent

Decentralized wastewater treatment systems enable wastewater to be treated at the source for cleaner discharge into the environment, protecting public health while allowing for reuse for agricultural and other purposes. This study, conducted in Thailand, investigated a decentralized wastewater treatment system incorporating a physical and photochemical process. Domestic wastewater from a university campus and conventional septic tank effluent from a small community were filtered through a woven-fiber microfiltration (WFMF) membrane as pretreatment for ultraviolet (UV) disinfection. In domestic wastewater, WFMF reduced TSS (by 79.8%), turbidity (76.5%), COD (38.5%), and NO3 (41.4%), meeting Thailand irrigation standards for every parameter except BOD. In septic tank effluent, it did not meet Thailand irrigation standards, but reduced TSS (by 77.9%), COD (37.6%), and TKN (13.5%). Bacteria (total coliform and Escherichia coli) and viruses (MS2 bacteriophage) passing through the membrane were disinfected by flow-through UV reactors containing either a low-pressure mercury lamp or light-emitting diodes (LEDs) emitting an average peak wavelength of 276 nm. Despite challenging and variable water quality conditions (2% < UVT < 88%), disinfection was predictable across water types and flow rates for both UV sources using combined variable modeling, which enabled us to estimate log inactivation of other microorganisms. Following UV disinfection, wastewater quality met the WHO standards for unrestricted irrigation.

scholarly journals A Preliminary Study on the Use of Xylit as Filter Material for Domestic Wastewater Treatment

2021 ◽  
Vol 11 (11) ◽  
pp. 5281
Author(s):  
Marcin Spychała ◽  
Tadeusz Nawrot ◽  
Radosław Matz
Keyword(s):  
Quality Indicators ◽  
Initial Period ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Filter Material ◽  
Stage I ◽  
Stage Ii ◽  
Septic Tank ◽  
Preliminary Stage ◽  
Wastewater Quality

The aim of the study was to verify two morphological forms (“angel hair” and “scraps”) of xylit as a trickling filter material. The study was carried out on two types of polluted media: septic tank effluent (STE) and seminatural greywater (GW). The basic wastewater quality indicators, namely, chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total suspended solids (TSS), ammonium nitrogen (NNH4), and total phosphorus (Ptot) were used as the indicators of treatment efficiency. Filtering columns filled with the investigated material acted as conventional trickling filters at a hydraulic load of 376–472 cm3/d during the preliminary stage, 198–245 cm3/d during stage I, and 184–223 cm3/d during stage II. The removal efficiency of the two morphological forms of xylit did not differ significantly. The average efficiencies of treatment were as follows: for COD, over 70, 80, and 85% for preliminary stage, stage I and stage II, respectively; for BOD5, 77–79% (preliminary stage); for TSS, 42% and 70% during the preliminary stage, and 88, 91, and 65% during stage I; for NNH4, 97–99% for stage I and 36–49% for stage II; for Ptot, 51–54% for stage I and 52–56% for stage II. The study demonstrated that xylit was a material highly effective in wastewater quality indicators removal, even during the initial period of its use.

scholarly journals Impact of green roof plant species on domestic wastewater treatment

2021 ◽  
pp. 100059
Author(s):  
Lijiao Liu ◽  
Junjun Cao ◽  
Mehran Ali ◽  
Jiaxin Zhang ◽  
Zhaolong Wang
Keyword(s):  
Wastewater Treatment ◽  
Plant Species ◽  
Green Roof ◽  
Domestic Wastewater ◽  
Domestic Wastewater Treatment

Nitrite reduction and methanogenesis in a single-stage UASB reactor

2015 ◽  
Vol 72 (12) ◽  
pp. 2236-2242 ◽  
Author(s):  
L. I. Borges ◽  
C. M. López-Vazquez ◽  
H. García ◽  
J. B. van Lier
Keyword(s):  
Domestic Wastewater ◽  
High Strength ◽  
Single Stage ◽  
Nitrite Reduction ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Organic Loading Rate ◽  
Anaerobic Sludge ◽  
N Removal

In this study, nitrite reduction and methanogenesis in a single-stage upflow anaerobic sludge blanket (UASB) reactor was investigated, using high-strength synthetic domestic wastewater as substrate. To assess long-term effects and evaluate the mechanisms that allow successful nitrite reduction and methanogenesis in a single-stage UASB, sludge was exposed to relatively high nitrite loading rates (315 ± 13 mgNO2−-N/(l.d)), using a chemical oxygen demand (COD) to nitrogen ratio of 18 gCOD/gNO2−-N, and an organic loading rate of 5.4 ± 0.2 gCOD/(l.d). In parallel, the effects of sludge morphology on methanogenesis inhibition were studied by performing short-term batch activity tests at different COD/NO2−-N ratios with anaerobic sludge samples. In long-term tests, denitrification was practically complete and COD removal efficiency did not change significantly after nitrite addition. Furthermore, methane production only decreased by 13%, agreeing with the reducing equivalents requirement for complete NO2− reduction to N2. Apparently, the spatial separation of denitrification and methanogenesis zones inside the UASB reactor allowed nitrite reduction and methanogenesis to occur at the same moment. Batch tests showed that granules seem to protect methanogens from nitrite inhibition, probably due to transport limitations. Combined COD and N removal via nitrite in a single-stage UASB reactor could be a feasible technology to treat high-strength domestic wastewater.

Removal Efficiency of Three Cold-Climate Constructed Wetlands Treating Domestic Wastewater: Effects of Temperature, Seasons, Loading Rates and Input Concentrations

1999 ◽  
Vol 40 (3) ◽  
pp. 273-281 ◽  
Author(s):  
Trond Mæhlum ◽  
Per Stålnacke
Keyword(s):  
Organic Matter ◽  
Constructed Wetlands ◽  
Domestic Wastewater ◽  
Cold Climate ◽  
Treatment Efficiency ◽  
Loading Rates ◽  
P Sorption ◽  
Percentage Points ◽  
Effects Of Temperature ◽  
Pre Treatment

This paper outlines the influence of temperature, flow rate and input concentrations on the treatment efficiency of organic matter and nutrients in constructed wetlands (CWs). Three integrated 10 PE systems with horizontal subsurface flow (HSF) treating domestic wastewater are described. Particular attention is devoted to: (1) aerobic pre-treatment in vertical-flow filters, (2) filter media with high phosphorus (P) sorption capacity, and (3) the treatment efficiency during winters. Aerobic pre-treatment followed by CW units including P sorption media removed most organic matter (BOD&gt; 75%), P (&gt; 90%) and total and ammonia N (40-80%). P retention was relatively stable in wetland filters, both with lightweight aggregates and ferruginous sand during 3-6 years of monitoring. Iron-rich sand from Bsh and Bs horizons of ferro-humic podzols was efficient for P sorption, but removal efficiencies of COD, TOC and SS were negative. The differences in efficiency between cold and warm periods were less than 10 percentage points for all parameters. It is anticipated that temperature effects are partially compensated by the large hydraulic retention time. The findings suggest that HSF systems do not require vegetation.

scholarly journals PLANNING OF DOMESTIC WASTEWATER FACILITIES (CASE STUDY: BABAKAN VILLAGE, CIPARAY DISTRICT, BANDUNG REGENCY)

2021 ◽  
Vol 5 (2) ◽  
pp. 73-82
Author(s):  
Deni Rusmaya ◽  
Evi Afiatun ◽  
Muhammad Al Hadad
Keyword(s):  
Domestic Wastewater ◽  
Primary Data ◽  
Septic Tank ◽  
Planning Stage ◽  
Priority Area ◽  
Community Needs ◽  
Technical Requirements ◽  
Domestic Wastewater Treatment ◽  
Treatment Facilities ◽  
Wastewater Infrastructure

Babakan Village has a problem that there is still a lack of facilities for wastewater. This condition can be seen from the access to the toilets of 2436 households; only around 1506 families have access to family/ shared latrines and 625 households that meet technical requirements. For this reason, this plan is useful for increasing access and meeting community needs for domestic wastewater treatment facilities in the study area. This planning stage begins with a survey and sanitation inspection to determine 3 priority areas for handling. Determinants of this priority area use the method of scoring and weighting the risk. The weighting results put sub village 02 with a score of 2.3, sub village 05 with a score of 2.25, and RW 10 with a risk value of 2 as the priority area for planning handlers. Primary data collected will be used as a consideration for determining the technology to be applied. The technology chosen for processing is the communal septic tank for people who do not have treatment. In contrast, for the washing bath, toilet with a biofilter unit for people who do not have wastewater infrastructure.

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