scholarly journals Evaluation of Pollutant Removal Efficiency by Small-Scale Nature-Based Solutions Focusing on Bio-Retention Cells, Vegetative Swale and Porous Pavement

Water ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 2361
Author(s):  
Anik Dutta ◽  
Arlex Sanchez Torres ◽  
Zoran Vojinovic
Keyword(s):  
Suspended Solids ◽  
Pollutant Removal ◽  
Water Quantity ◽  
Small Scale ◽  
Natural Phenomena ◽  
Rapid Urbanization ◽  
Quality Aspects ◽  
Porous Pavement ◽  
Aging Infrastructure ◽  
Rainfall Patterns

Rapid urbanization, aging infrastructure, and changes in rainfall patterns linked to climate change have brought considerable challenges to water managers around the world. Impacts from such drivers are likely to increase even further unless the appropriate actions are put in place. Floods, landslides, droughts and water pollution are just a few examples of such impacts and their corresponding consequences are in many cases devastating. At the same time, it has become a well-accepted fact that traditional (i.e., grey infrastructure) measures are no longer effective in responding to such challenges. Nature-based solutions (NBS) have emerged as a new response towards hydro-meteorological risk reduction and the results obtained to date are encouraging. However, their application has been mainly in the area of water quantity management with few studies that report on their efficiency to deal with water quality aspects. These solutions are based on replicating natural phenomena and processes to solve such problems. The present paper addresses the question of three NBS systems, namely, bio-retention cells, vegetative swales and porous pavements, for the removal of total suspended solids (TSS), total nitrogen (TN) and total phosphorus (TP) when applied in different configurations (single or networked). The results presented in this paper aim to advance the understanding of their performances during varying rainfall patterns and configurations and their potential application conditions.

Field-Scale Studies of Subsurface Flow Constructed Wetlands for Stormwater Quality Enhancement

1997 ◽  
Vol 32 (1) ◽  
pp. 101-118 ◽  
Author(s):  
Q.J. ROCHFORT ◽  
W.E. Watt ◽  
J. Marsalek ◽  
B.C. Anderson ◽  
A.A. Crowder
Keyword(s):  
Organic Carbon ◽  
Constructed Wetlands ◽  
Suspended Solids ◽  
Nutrient Loading ◽  
Subsurface Flow ◽  
Reaction Rates ◽  
Pollutant Removal ◽  
Order Kinetic ◽  
Dissolved Metals ◽  
Subsurface Flow Constructed Wetlands

Abstract Two subsurface flow constructed wetlands were tested for pollutant removal performance in conjunction with an on-line stormwater detention pond, in Kingston Township, Ontario. The 4.9 m2 wetland cells were filled with 9 mm limestone gravel, and planted with cattail, common reed and spike rush. Changes in nutrient (total organic carbon, PO43- and NH4+), suspended solids and metal (Cu, Pb, Zn) concentrations were used to assess performance. Contaminant removal occurred through a combination of physical, chemical and biological means. As with any biological system, variation in performance of stormwater wetlands can be expected to occur as a result of fluctuations in contaminant loading, contact time and ambient environmental conditions. Storm pond effluent was delivered in continuous flow through the wetlands (during baseflow and event conditions), with a detention time of 1 to 3 days. The wetlands were able to maintain removal rates of up to 39% for orthophosphate even during the more severe conditions of fall dieback. Average removal of suspended solids (46%) and dissolved metals (Cu 50%) remained similar throughout all tests. Organic carbon was reduced by less than 10% during these tests. Low nutrient levels in the pond effluent were supplemented by spiking with sources of carbon, nitrogen and phosphorus during pulsed loading conditions. Daily sampling produced a time series, which illustrated the rates of decline in concentration of nutrients. First order kinetic assimilation rates ranged from 1.7 d-1 for NH4002B to 0.12 d-1 for organic carbon, which were noticeably lower when compared with municipal and industrial wastewater treatment rates. Three methods of sizing stormwater wetlands (impervious surface area, volumetric load and kinetic reaction rates) were compared using the same design storm and data from this study. From this comparison it was seen that the kinetic sizing approach proved to be the most versatile, and allowed for adaptation to northern climatic conditions and anticipated nutrient loading.

Performance Analysis of the Rotating Biological Contactor Process Based on Particle Fraction and Improvement of Final Effluent Quality

1991 ◽  
Vol 23 (7-9) ◽  
pp. 1457-1466 ◽  
Author(s):  
Kazuhiro Tanaka ◽  
Minoru Tada ◽  
Mitsuo Ito ◽  
Noritugu Shimizu
Keyword(s):  
Suspended Solids ◽  
Fine Particles ◽  
Wastewater Treatment Plants ◽  
Small Scale ◽  
Particle Fraction ◽  
Effluent Quality ◽  
Rotating Biological Contactors ◽  
Activated Sludge Processes ◽  
Fraction Method ◽  
Final Effluent

Biofilm processes are, in general, suitable for small-scale wastewater treatment plants. However, final effluent qualities of biofilm processes are not as good as those of activated sludge processes due to fine particles remaining in the effluents. To improve the effluent qualities of the Rotating Biological Contactors (RBC) process, the behavior of fine particles through the process and the removal of fine particles with solids-liquid separation methods, rapid filtration and coagulation-filtration, were investigated using the particle fraction method. The results are as follows:–An increase of the hydraulic retention time (HRT) in the RBC reactor reduced the amount of fine particles and increased the amount of coarse suspended solids of 44 µm or more in diameter, which are easily removed by clarification. Thus, the final effluent qualities were improved by the increase of HRT.–Suspended solids in effluent from the RBC process at the standard loading are so fine that improvement of the quality is not expected by only lowering the overflow rate of a final clarifier. In contrast, rapid filtration or a coagulation-filtration process is effective. The supended solid concentration and transparency of the effluent from the final clarifier was improved by a factor of two to four, and then BOD of the final effluent was removed by 40-85%.

scholarly journals Quality aspects of pepino dulce fruits in distinct ripening stages, packaging forms and storage conditions

2020 ◽  
Vol 23 ◽  
Author(s):  
Neide Botrel ◽  
Raphael Augusto de Castro e Melo
Keyword(s):  
Fruit Quality ◽  
Block Design ◽  
Titratable Acidity ◽  
Storage Conditions ◽  
Matter Content ◽  
Soluble Solids ◽  
Small Scale ◽  
Dry Matter Content ◽  
Ripening Stages ◽  
Quality Aspects

Abstract Pepino dulce (Solanum muricatum Aiton) or Pepino has been growing to produce edible, juicy and attractive fruits. The imported fruits and national small scale of Pepino dulce production are currently stored and commercialized under the absence of postharvest handling recommendations. Therefore, this work aimed to evaluate the quality aspects of Pepino dulce fruits in distinct ripening stages, forms of packaging and conditions of storage. The trial was conducted in a 2x2x2 factorial scheme - 2 ripening stages (ripe and immature) x 2 forms of packaging (with and without wrapping in plastic film) x 2 conditions of storage (room: 25 °C ± 2 ºC and 57% ± 5% of relative humidity (RH); cold: under refrigeration 10 °C ± 2 °C and 85% ± 5% of RH) – in a complete randomized block design. Fruit quality attributes, such as vitamin C, chemical and phenolic content, fruit color (mesocarp), firmness, dry matter content, total titratable acidity (TA), total soluble solids and pH, were evaluated. Fruits showed a centesimal composition with low calories and a significant content of potassium (K), phosphorus (P) and magnesium (Mg), which can contribute to the daily supply of these elements. For commercialization purposes, the association of packaging (plastic wrapping film) and refrigerated storage (cold: 10 °C ± 2 °C and 85% ± 5% of RH) to maintain the characteristics of fruit quality after a 15 days period is more important than its individual use.

scholarly journals Evaluation of Low Impact Development and Nature-Based Solutions for stormwater management: a fully distributed modelling approach

2019 ◽  
Author(s):  
Yangzi Qiu ◽  
Abdellah Ichiba ◽  
Igor Da Silva Rocha Paz ◽  
Feihu Chen ◽  
Pierre-Antoine Versini ◽  
...  
Keyword(s):  
High Resolution ◽  
Stormwater Management ◽  
Low Impact Development ◽  
Peak Discharge ◽  
Small Scale ◽  
Spatial Distributions ◽  
Land Uses ◽  
Runoff Volume ◽  
Total Runoff ◽  
Porous Pavement

Abstract. Currently, Low Impact Development (LID) and Nature-Based Solutions (NBS) are widely accepted as sustainable approaches for urban stormwater management. However, their complex impacts depend on the urban environmental context as well as the small-scale heterogeneity, which need to be assessed by using the fully distributed hydrological model and high resolution data at small scale. In this paper, a case study (Guyancourt), located in the South-West of Paris, was explored. Three sets of high resolution X-band radar data were applied to investigate the impact of variability of spatial distribution of rainfall. High resolution geographic information has been processed to identify the suitable areas that can be covered by the LID/NBS practices, porous pavement, green roof, and rain garden. These individual practices, as well as the combination of the three, were implemented as scenarios in a fully distributed and physically-based Multi-Hydro model, which takes into consideration the variability of the whole catchment at 10 m scale. The performance of LID/NBS scenarios are analysed with two indicators (total runoff volume and peak discharge reduction), with regards to the hydrological response of the original catchment (baseline scenario). Results are analysed with considering the coupling effect of the variability of spatial distributions of rainfall and land uses. The performance of rain garden scenario is better than scenario of green roof and porous pavement. The most efficient scenario is the combination of the three practices that can reduce total runoff volume up to 51 % and peak discharge up to 53 % in the whole catchment, and the maximum values of the two indictors in three sub-catchments reach to 60 % and 61 % respectively. The results give credence that Multi-Hydro is a promising model for evaluating and quantifying the spatial variability of hydrological responses of LID/NBS practices, because of considering the heterogeneity of spatial distributions of precipitation and land uses. Potentially, it can guide the decision-making process of the design of LID/NBS practices in urban planning.

scholarly journals Preliminary Research on Planning of Decentralizing Ancient Towns in Small-Scale Famous Historic and Cultural Cities with a Case Study of Tingchow County, Fujian Province

2019 ◽  
Vol 11 (10) ◽  
pp. 2911 ◽  
Author(s):  
Min Yin ◽  
Jiangang Xu ◽  
Zhongyuan Yang
Keyword(s):  
Land Use ◽  
Urban Landscape ◽  
Small Scale ◽  
Rapid Urbanization ◽  
Resident Population ◽  
Administrative Functions ◽  
Residential Land Use ◽  
Resource Space ◽  
Historic Cities

The urban planning industry has always been concerned about conserving and developing historic cities in a sustainable and balanced way. However, unreasonable planning and accumulative effects brought by rapid urbanization prevent the conservation of small-scale famous historic and cultural cities. Taking Tingchow county as an example, this paper focused on sustainable development and the Historic Urban Landscape Approach, and determined the urban functions and specific tasks of various planning of its ancient town with the help of public opinions. This paper mainly aimed at providing guidance on urban decentralization from two perspectives. Firstly, it compared the types of land use and its ratio among famous cities of similar scales, and results showed that it is advisable to reduce three-class residential land use and unnecessary administrative functions. Secondly, it estimated the moderate resident population in different degrees of development, and calculated the upper limit of resource space bearing capacity (REBC) of scenic spots under the guidance of sustainable tourism. Results showed that it is recommended to decentralize and resettle 20%~30% of the resident population, and to control the tourist population below 12,000 per day. As the preliminary work of planning, this paper focused on the scientific planning and availability of decentralization, and reflected an expectation for the mode of public participation and quantitative planning.

scholarly journals The Efficiency and Reliability of Pollutant Removal in a Hybrid Constructed Wetland with Common Reed, Manna Grass, and Virginia Mallow

Water ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1445 ◽  
Author(s):  
Michał Marzec ◽  
Krzysztof Jóźwiakowski ◽  
Anna Dębska ◽  
Magdalena Gizińska-Górna ◽  
Aneta Pytka-Woszczyło ◽  
...  
Keyword(s):  
Total Nitrogen ◽  
Total Phosphorus ◽  
Constructed Wetland ◽  
Suspended Solids ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Total Suspended Solids ◽  
Common Reed ◽  
Pollutant Removal ◽  
Limit Values

In this paper, the pollutant removal efficiency and the reliability of a vertical and horizontal flow hybrid constructed wetland (CW) planted with common reed, manna grass, and Virginia mallow were analyzed. The wastewater treatment plant, located in south-eastern Poland, treated domestic sewage at an average flow rate of 2.5 m3/d. The tests were carried out during five years of its operation (2014–2018). The following parameters were measured: biochemical oxygen demand (BOD5), chemical oxygen demand (COD), total suspended solids, total nitrogen, and total phosphorus. The results showed that more than 95% of BOD5, COD, and total phosphorus was removed in the tested CW system. The average effectiveness of removal of total suspended solids and total nitrogen exceeded 86%. A reliability analysis performed using the Weibull probability model showed that the removal reliability in the tested CW was very high for BOD5, COD, total suspended solids, and total phosphorus (100%). The probability that the total nitrogen concentration in the treated effluents would reach the limit value (30 mg/L) established for effluents discharged from a treatment plant of less than 2000 PE (population equivalent) to standing waters was 94%. The values of all the pollution indicators in wastewater discharged to the receiver were significantly lower than the limit values required in Poland. The investigated hybrid CW system with common reed, manna grass, and Virginia mallow guaranteed stable low values of BOD5, COD, total suspended solids, and total phosphorus in the treated wastewater, which meant it was highly likely to be positively evaluated in case of an inspection.

Hydraulic and treatment performance of pervious pavements under variable drying and wetting regimes

2011 ◽  
Vol 64 (8) ◽  
pp. 1692-1699 ◽  
Author(s):  
C. F. Yong ◽  
A. Deletic ◽  
T. D. Fletcher ◽  
M. R. Grace
Keyword(s):  
Suspended Solids ◽  
High Flow ◽  
Pollutant Removal ◽  
Low Flow ◽  
Storm Event ◽  
Stormwater Treatment ◽  
Storm Events ◽  
Treatment Technology ◽  
Porous Asphalt ◽  
Treatment Performance

Pervious pavements are an effective stormwater treatment technology. However, their performance under variable drying and wetting conditions have yet to be tested, particularly under a continuous time scale. This paper reports on the clogging behaviour and pollutant removal efficiency of three pervious pavement types over 26 accelerated years. These pavements were monolithic porous asphalt (PA), Permapave (PP) and modular Hydrapave (HP). Over a cycle of 13 days, the period of which was equivalent to the average annual Brisbane, Australia rainfall (1,200 mm), the pavements were randomly dosed with four different flows. Drying events of 3 h duration were simulated during each flow. Inflow and outflow samples were collected and analysed for Total Suspended Solids (TSS), Total Phosphorus (TP) and Total Nitrogen (TN). To evaluate the rate of clogging, a 1 in 5 year Brisbane storm event was simulated in the 6th, 8th, 12th, 16th, 20th and 24th week. Under normal dosing conditions, none of the pavements showed signs of clogging even after 15 years. However, under storm conditions, both PA and HP started to clog after 12 years, while PP showed no signs of clogging after 26 years. The drying and various flow events showed no effects in TSS removal, with all systems achieving a removal of approximately 100%. The average TP removal was 20% for all flows except for low flow, which had a significant amount of leaching over time. Leaching from TN was also observed during all flows except high flow. The TSS, TP and TN results observed during storm events were similar to that of high flow.

Is the hydrological response of Nature-Based Solutions related to the spatial variability of rainfall?

2020 ◽  
Author(s):  
Yangzi Qiu ◽  
Ioulia Tchiguirinskaia ◽  
Daniel Scherzter
Keyword(s):  
Spatial Variability ◽  
Green Roof ◽  
Urban Environments ◽  
Rainfall Data ◽  
Percentage Error ◽  
Small Scale ◽  
Hydrological Response ◽  
Urban Catchment ◽  
Rainfall Events ◽  
Porous Pavement

<p>Nature-Based Solutions (NBS) practices provide many benefits for sustainable development of urban environments, one of which is their ability to mitigate the urban waterlogging. In many previous studies, the performances of NBS practices are analysed with the semi-distributed model and artificial rainfall without considering the spatial variability of rainfall. However, the NBS practices are decentralized in urban areas, their hydrological response is very depends on the small-scale heterogeneity of urban environments. Therefore, this research aims to investigate the impacts of small-scale rainfall variability on the hydrological responses of NBS practices.</p><p>In this study, the hydrological response of NBS practices was analysed at the urban catchment scale. A 5.2 km<sup>2</sup> semi-urban catchment (Guyancourt, located in the South-West of Paris) are investigated under various future NBS implementation scenarios (porous pavement, green roof, rain garden and combined). Regarding the objective of this research, three typical rainfall events are selected. Three sets of distributed rainfall data at a high resolution of 250 m×250 m×3.41 min were obtained from the X-band radar of Ecole des Ponts ParisTech (ENPC). In addition, three sets of corresponded homogeneous rainfall data are applied and used for comparing with the distributed one. Furthermore, a fully distributed and grid based hydrological model (Multi-Hydro), developed at ENPC, which takes into consideration the spatial variability of the whole catchment at 10 m scale. The hydrological response of NBS scenarios was analysed with the percentage error on total volume and peak discharge, with regards to the baseline scenario (current configuration).</p><p>Results show that the spatial variability of rainfall has the impact on the hydrological response of NBS scenarios in varying degrees, and it is more evident for green roof scenario. In three rainfall events, the maximum percentage error on peak discharge of green roof scenario under distributed rainfall is 23 %, while that of the green roof scenario under homogeneous rainfall is 17.7%. Overall, the results suggest that the implementation of porous pavement and rain garden is more flexible than implementation of green roof in a semi-urban catchment.</p>

Impact of timber harvesting and production on streams: A review

1989 ◽  
Vol 40 (5) ◽  
pp. 519 ◽  
Author(s):  
IC Campbell ◽  
TJ Doeg
Keyword(s):  
Water Quality ◽  
Suspended Solids ◽  
Peak Flow ◽  
Timber Harvesting ◽  
Water Quantity ◽  
Buffer Zones ◽  
Protection Measure ◽  
Flow Transport ◽  
Stream Biota ◽  
Retention Structures

Timber harvesting operations have significant effects on both water quantity and water quality. The effects on water quantity have been well documented both in Australia and elsewhere. The effects on water quality are less widely appreciated, and include elevated concentrations of dissolved salts, suspended solids and nutrients, especially during peak flow periods. Several Australian studies have failed to measure peak flow transport of suspended solids, or have measured it inadequately, thus severely underestimating transport. The major short-term effects of timber harvesting on the aquatic biota result from increased sediment input into streams or increased light through damage to, or removal of, the riparian vegetation. Sediment which settles on, or penetrates into, the stream bed is of more concern than suspended sediment, and can lead to long-term deleterious changes to fish and invertebrate populations. Increased light causes an increase in stream primary production which may increase invertebrate densities, and alter community composition. These biological consequences have not yet been adequately investigated in Australia. Longer-term effects, as yet not investigated in Australia, include changes to stream structure as the regrowth forest has fewer large logs to fall into the stream. These large logs play a major role as habitat and retention structures in streams. There has been no attempt to evaluate the effects of timber production activities, including pesticide use and fuel reduction burning, on the Australian stream biota. Likewise, although buffer zones are widely advocated as a protection measure for streams in Australia, there have been no studies to evaluate their effectiveness.

Experimental investigation on water treatment by the combined nano MgO–nanofiltration technique

2011 ◽  
Vol 63 (11) ◽  
pp. 2542-2546 ◽  
Author(s):  
Keqiang Zhang ◽  
Yi An ◽  
Feng Wang ◽  
Lingling Lin ◽  
Haigang Guo
Keyword(s):  
Heavy Metals ◽  
Experimental Investigation ◽  
Water Treatment ◽  
Suspended Solids ◽  
Pollutant Removal ◽  
Polluted Water ◽  
Operating Pressure ◽  
Nitrogen Species ◽  
Combined System ◽  
Mg Content

A combined system using nano MgO and nanofiltration (NF) membrane was established to purify polluted water in this experiment. The turbidity, permanganate index, UVA254, colony counts and the concentrations of NO3−, NO2−, NH4+, Fe, Mn and Mg of the effluents from each unit of this combined system were measured to investigate the pollutant removal of this system. Based on the results obtained, the combined nano MgO–NF system could efficiently remove many kinds of pollutants in this experiment, including organic matter, nitrogen species, heavy metals, suspended solids and bacteria. And the effluents could meet the standard of drinking water. Furthermore, increasing the nano MgO dosage could not elevate the removal ratio of the pollutants, but only increase the Mg content of the effluent. Thus, 0.05 g L−1 of nano MgO may be a suitable dosage for 2,000 L of polluted water treatment. Also, the operating pressure of NF membrane had no significant effect on pollutant removal when the operating pressure of NF membrane was increased from 0.3 to 0.9 MPa.

Sign in / Sign up

Export Citation Format

Share Document