A Transdisciplinary Approach for Water Pollution Control

Chongrak Polprasert,Warunsak Liamlaem 대한환경공학회 2014 Environmental Engineering Research Vol.19 No.3

Despite the enormous technical and economic efforts to improve environmental conditions, currently about 40% of the global population (or 2 billion people) are still lack access to safe water supply and adequate sanitation facilities. Pollution problems and transmission of water- related diseases will continue to proliferate. The rapid population growth and industrialization will lead to a reduction of arable land, thus exacerbating the food shortage problems and threatening environmental sustainability. Natural systems in this context are a transdisciplinary approach which employs the activities of microbes, soil and/or plants in waste stabilisation and resource recovery without the aid of mechanical or energy-intensive equipments. Examples of these natural systems are: waste stabilisation ponds, aquatic weed ponds, constructed wetlands and land treatment processes. Although they require relatively large land areas, the natural systems could achieve a high degree of waste stabilisation and at the same time, yield potentials for waste recycling through the production of algal protein, fish, crops, and plant biomass. Because of the complex interactions occurring in the natural systems, the existing design procedures are based mainly on empirical or field experience approaches. An integrated kinetic model encompassing the activities of both suspended and biofilm bacteria and some important engineering parameters has been developed which could predict the organic matter degradation in the natural systems satisfactorily.

ROLE OF BIOFILM ACTIVITY IN WATER HYACINTH POND DESIGN AND OPERATION

( Chongrak Polprasert,Nawa Raj Khatiwada ) 한국물환경학회 1997 제6차 국제수질보전학회 아시아 태평양지역 학술회의 Vol.1 No.-

Integrated Eco-Engineering Design for Sustainable Management of Fecal Sludge and Domestic Wastewater

Koottatep, Thammarat,Polprasert, Chongrak,Laugesen, Carsten H. Korean Wetlands Society 2007 한국습지학회지 Vol.9 No.1

Constructed wetlands and other aquatic systems have been successfully used for waste and wastewater treatment in either temperate or tropical regions. To treat waste or wastewater in a sustainable manner, the integrated eco-engineering designs are explained in this paper with 2 case studies: (i) a combination of vertical-flow constructed wetland (CW) with plant irrigation systemfor fecal sludge management and (ii) integrated CW units with landscaping at full-scale application for domestic wastewater treatment. The pilot-scale study of fecal sludge management employed 3 vertical-flow CW units, each with a dimension of $5{\times}5{\times}0.65m$ (width ${\times}$ length ${\times}$ media depth) and planted with cattails (Typha augustifolia). At the solid loading rate of 250 kg total solids (TS)/$m^2.yr$ and a 6-day percolate impoundment, the CW system could achieve chemical oxygen demand (COD), TS and total Kjeldahl nitrogen (TKN) removal efficiencies in the range of 80 - 96%. The accumulated sludge layers of about 80 - 90 cm was found at the CW bed surface after operating the CW units for 7 years, but no clogging problem has been observed. The CW percolate was applied to 16 irrigation Sunflower plant (Helianthus annuus) plots, each with a dimension of $4.5{\times}4.5m$ ($width{\times}length$). In the study, the CW percolate were fed to the treatment plots at the application rate of 7.5 mm/day but the percolate was mixed with tap water at different ratio of 20%, 80% and 100%. Based on a 1-year data of 3-crop plantation were experimented, the contents of Zn, Mn and Cu in soil of the experimental plots were found to increase with increasing in CW percolate ratios. The highest plant biomass yield and oil content of 1,000 kg/ha and 35%, respectively, were obtained from the plots fed with 20% or 50% of the CW percolate, whereas no accumulation of heavy metals in the plant tissues (i.e. leaves, stems and flowers) of the sunflower is found. In addition to the pilot-scale and field experiments, a case study of the integrated CW systems for wastewater treatment at Phi Phi Island (a Tsunami-hit area), Krabi province, Thailand is illustrated. The $5,200-m^2$ CW systems on Phi Phi Island are not only for treatment of $400m^3/day$ wastewater from hotels, households or other domestic activities, but also incorporating public consultation in the design processes, resulting in introducing the aesthetic landscaping as well as reusing of the treated effluent for irrigating green areas on the Island.

ROLE OF PLANT UPTAKE ON NITROGEN REMOVAL IN CONSTRUCTED WETLANDS LOCATED IN THE TROPICS

( Thammarat Koottatep,Chongrak Polprasert ) 한국물환경학회 1997 제6차 국제수질보전학회 아시아 태평양지역 학술회의 Vol.1 No.-

Integrated Eco-Engineering Design for Sustainable Management of Fecal Sludge and Domestic Wastewater

Thammarat Koottatep,Chongrak Polprasert,Carsten H. Laugese 한국습지학회 2007 한국습지학회지 Vol.9 No.1

Constructed wetlands and other aquatic systems have been successfully used for waste and wastewater treatment in either temperate or tropical regions. To treat waste or wastewater in a sustainable manner, the integrated eco-engineering designs are explained in this paper with 2 case studies: (i) a combination of vertical-flow constructed wetland (CW) with plant irrigation systemfor fecal sludge management and (ii) integrated CW units with landscaping at full-scale application for domestic wastewater treatment. The pilot-scale study of fecal sludge management employed 3 vertical-flow CW units, each with a dimension of 5 x 5 x 0.65 m (width x length x media depth) and planted with cattails (Typha augustifolia). At the solid loading rate of 250 kg total solids (TS)/m2.yr and a 6-day percolate impoundment, the CW system could achieve chemical oxygen demand (COD), TS and total Kjeldahl nitrogen (TKN) removal efficiencies in the range of 80 - 96%. The accumulated sludge layers of about 80 – 90 cm was found at the CW bed surface after operating the CW units for 7 years, but no clogging problem has been observed. The CW percolate was applied to 16 irrigation Sunflower plant (Helianthus annuus) plots, each with a dimension of 4.5 x 4.5 m (width x length). In the study, the CW percolate were fed to the treatment plots at the application rate of 7.5 mm/day but the percolate was mixed with tap water at different ratio of 20%, 80% and 100%. Based on a 1-year data of 3-crop plantation were experimented, the contents of Zn, Mn and Cu in soil of the experimental plots were found to increase with increasing in CW percolate ratios. The highest plant biomass yield and oil content of 1,000 kg/ha and 35%, respectively, were obtained from the plots fed with 20% or 50% of the CW percolate, whereas no accumulation of heavy metals in the plant tissues (i.e. leaves, stems and flowers) of the sunflower is found. In addition to the pilot-scale and field experiments, a case study of the integrated CW systems for wastewater treatment at Phi Phi Island (a Tsunami-hit area), Krabi province, Thailand is illustrated. The 5,200-m2 CW systems on Phi Phi Island are not only for treatment of 400 m3/day wastewater from hotels, households or other domestic activities, but also incorporating public consultation in the design processes, resulting in introducing the aesthetic landscaping as well as reusing of the treated effluent for irrigating green areas on the Island.

Hydraulic Evaluation and Performance of On-Site Sanitation Systems in Central Thailand

Thammarat Koottatep,Rawintra Eamrat,Tatchai Pussayanavin,Chongrak Polprasert 대한환경공학회 2014 Environmental Engineering Research Vol.19 No.3

On-site sanitation systems are typically installed to treat grey and toilet wastewaters in areas without sewer and centralized treatment systems. It is well known that, due to inappropriate design and operation, treatment performance of these systems in developing countries is not satisfactory in the removal of pathogens and organic matters. This research aimed to investigate the hydraulic conditions occurring in some on-site sanitation systems and the effects of hydraulic retention times (HRTs) on the system performance. The experiments were conducted with a laboratory-scale septic tank (40L in size) and an actual septic tank (600L in size), to test the hydraulic conditions by using tracer study with HRTs varying at 12, 24 and 48 hr. The experimental results showed the dispersion numbers to be in the range of 0.017-0.320 and the short-circuit ratios in the range of 0.014-0.031, indicating the reactors having a high level of sort-circuiting and approaching complete-mix conditions. The removal efficiency of BOD5 was found to be 67% and the k30 values for BOD5 was 2.04 day-1. A modified complete-mix model based on the relationship between BOD5 removal efficiencies and HRTs was developed and validated with actual-scale septic tank data having a correlation coefficient (R2) of 0.90. Therefore, to better protect our environment and minimizing health risks, new generation toilets should be developed that could minimize short-circuiting and improving treatment performance.

Performance and kinetic modeling of modified attached-growth anoxic-oxic-anoxic reactor for onsite sanitation system treating septic tank effluent

Thammarat Koottatep,Sittikorn Kamngam,Chawalit Chaiwong,Chongrak Polprasert 대한환경공학회 2022 Environmental Engineering Research Vol.27 No.3

This paper investigated a combined process of a modified attached-growth anoxic-oxic-anoxic reactor (AG-AOAR) as a sustainable and effective post-treatment system for septic tank effluent was developed. The AG-AOAR was operated by varying hydraulic retention times (HRTs) from 24 to 72 h. The results showed that the AG-AOAR achieved highest removal efficiencies of 84, 66 and 91% of chemical oxygen demand (COD), total nitrogen (TN) and ammonium nitrogen (NH₄-N), respectively, under the HRT of 72 h, resulting its effluent meeting the international and national discharge quality standards for non-sewered sanitation system. The Stover-Kincannon model was applicable to describe the kinetic constants of COD, TN, and NH₄-N removal in the AG-AOAR (R² > 0.85). Accordingly, the maximum utilization rates (μmax) were determined to be 41.1, 0.15 and 0.50 g/(L-d) for COD, TN and NH₄-N removals, respectively, while the saturation constants (KB) were 57.7, 0.12 and 0.51 g/(L-d), respectively. These constant values could be applied for the design of the AG-AOAR to produce treated effluent meeting desired standards.

Removal of acetaminophen from wastewater by constructed wetlands with Scirpus validus

Vo Hoang Nhat Phong,Thammarat Koottatep,Saroj Kumar Chapagain,Atitaya Panuvatvanich,Chongrak Polprasert,Kyu Hong Ahn 대한환경공학회 2016 Environmental Engineering Research Vol.21 No.2

Since most of the existing wastewater treatment options lack the ability to treat micro-contaminants, the increased use of pharmaceuticals and personal care products (PPCPs) and release as human waste have become a serious concern in recent years. Constructed wetlands (CWs) are a low-cost technology for wastewater treatment, however, its performance in term of PPCPs removal has not yet been fully investigated. This study aimed to characterize the removal factors and efficiency of acetaminophen (ACT) removal by CWs. The results revealed the decreased concentrations of ACT with increasing hydraulic retention times (HRT) of 0, 3, 5 days. The contribution of removal factors was found to be varied with initial ACT concentration. At the low ACT concentration (i.e. 1 ppb), plant uptake was the dominant, followed by microbial and photolytic removal. In contrast, at the high ACT concentration (i.e. 100 ppb), microbial and photolytic removal were found as dominant factors. On the other hand, hydrogen peroxide (H₂O₂) concentration was found at higher level in the plant shoot than in the root probably due to occurrence of the Fenton reaction resulting in PPCPs removal.

Media configuration and recirculation of upflow anaerobic floating filter for piggery wastewater treatment

이승환,이홍신,Seongeok Lee,Sukhuma Chitapornpan,Chart Chiemchaisri,Chongrak Polprasert,안규홍 한국화학공학회 2007 Korean Journal of Chemical Engineering Vol.24 No.6