scholarly journals Sewage treatment by vermifiltration with synchronous treatment of sludge by earthworms: a low-cost sustainable technology over conventional systems with potential for decentralization

2008 ◽  
Vol 28 (4) ◽  
pp. 409-420 ◽  
Author(s):  
Rajiv K. Sinha ◽  
Gokul Bharambe ◽  
Uday Chaudhari
2011 ◽  
Vol 63 (10) ◽  
pp. 2411-2417 ◽  
Author(s):  
R. Reif ◽  
A. Besancon ◽  
K. Le Corre ◽  
B. Jefferson ◽  
J. M. Lema ◽  
...  

The presence in the aquatic environment of xenobiotics such as Pharmaceutical and Personal Care Products (PPCPs) has emerged as an issue of concern. Upgrading sewage treatment quality with modern technologies such as Membrane Bioreactors (MBRs) and/or implementing a further post-treatment might mitigate the release of xenobiotics into surface waters. The performance of two processes treating municipal sewage, a MBR and an Activated Sludge (AS) unit, have been compared in terms of PPCPs removal. Moreover, their effluents were treated using vertical flow reed beds. Both systems were operated under similar conditions, more specifically Hydraulic Retention Time (HRT), maintained at 8 hours, and Sludge Retention Time (SRT) set at 6 and 20 days. Pharmaceuticals belong to therapeutic groups such as antiepileptics (carbamazepine) and analgesics (ibuprofen, naproxen, diclofenac), whereas the personal care products are musk fragrances (galaxolide and tonalide). Xenobiotics removals achieved in the MBR showed better results, particularly for the acidic drugs ibuprofen (87% vs. 50%) and naproxen (56% vs. 6%) operating at low SRT. After filtration through vertical flow reed-beds, PPCPs content in effluents was decreased, below 1 ppb in most cases, improving the effluent quality and confirming reed-beds as an interesting low cost alternative in order to attenuate xenobiotics contamination.


2021 ◽  
Author(s):  
Siddhartha Ghosh ◽  
Allan Lambor Marbaniang ◽  
Ajmal Babu Mahasrankintakam ◽  
Radhika Pajgade ◽  
Subhrajit Dutta ◽  
...  

2021 ◽  
Vol 21 (7) ◽  
pp. 3882-3886
Author(s):  
Yong-Wook Jung ◽  
Jong Kyu Kim

In this study, nano-sized low cost titanium dioxide (TFS) was prepared using sludge from sewage treatment and performance was verified. To remove air pollutants, the photocatalytic degradation of methylene blue and efflorescence characteristics is assessed according to the mixing ratio of the nano-sized TFS by applying them to concrete sidewalk blocks. The photocatalytic degradation performance of concrete sidewalk blocks shows that the methylene blue removal rate of specimens containing 2.5%, 5%, and 10% of nano-sized TFS is 29%, 27%, and 38%, respectively. When the nano-sized TFS is mingled on the surface of the sidewalk block, the performance of anti-corrosion and antifouling showed excellency mainly due to the moisture blocking derived by the antifouling function of photocatalysts.


2019 ◽  
Vol 3 (1) ◽  
pp. 27 ◽  
Author(s):  
Samir Tayar ◽  
Renata Guerrero ◽  
Leticia Hidalgo ◽  
Denise Bevilaqua

The packing material selection for a bioreactor is an important factor to consider, since the characteristics of this material can directly affect the performance of the bioprocess, as well as the investment costs. Different types of low cost packing materials were studied in columns to reduce the initial and operational costs of biogas biodesulfurization. The most prominent (PVC pieces from construction pipes) was applied in a bench-scale biotrickling filter to remove the H2S of the biogas from a real sewage treatment plant in Brazil, responsible for 90 thousand inhabitants. At the optimal experimental condition, the reactor presented a Removal Efficiency (RE) of up to 95.72% and Elimination Capacity (EC) of 98 gS·m−3·h−1, similar to open pore polyurethane foam, the traditional material widely used for H2S removal. These results demonstrated the high potential of application of this packing material in a full scale considering the robustness of the system filled with this support, even when submitted to high sulfide concentration, fluctuations in H2S content in biogas, and temperature variations.


2020 ◽  
Vol 12 (16) ◽  
pp. 2575 ◽  
Author(s):  
Giuseppe Stanghellini ◽  
Fabrizio Del Bianco ◽  
Luca Gasperini

OpenSWAP is a class of innovative open architecture, low cost autonomous vehicles for geological/geophysical studies of shallow water environments. Although they can host different types of sensors, these vehicles were specifically designed for geophysical surveys, i.e., for the acquisition of bathymetric and stratigraphic data through single- and multibeam echosounders, side-scan sonars, and seismic-reflection systems. The main characteristic of the OpenSWAP vehicles is their ability of following pre-defined routes with high accuracy under acceptable weather and sea conditions. This would open the door to 4D (repeated) surveys, which constitute a powerful tool to analyze morphological and stratigraphic changes of the sediment/water interface and of the shallow substratum eventually caused by sediment dynamics (erosion vs. deposition), slumps and gravitative failures, earthquakes (slip along seismogenic faults and secondary effects of shaking), tsunamis, etc. The low cost and the open hardware/software architectures of these systems, which can be modified by the end users, lead for planning and execution of cooperative and adaptive surveys with different instruments not yet implemented or tested. Together with a technical description of the vehicles, we provide different case studies where they were successfully employed, carried out in environments not, or very difficultly accessed through conventional systems.


2011 ◽  
Vol 6 (3) ◽  
Author(s):  
C. T. Avellán ◽  
D. P. L. Rousseau ◽  
P. N. L. Lens

The 3600 dairy farms in south-western Uruguay, with about 750,000 cows in 2008, play an important economic role. Only about 200 of the farms have a sewage treatment system, since no legal regulations for the disposal of effluents exist, the cost of construction is high and neither direct benefits nor incentives are given. The current systems are mainly lagoons that often lack maintenance, resulting in the eutrophication of rivers. One of our goals was to implement a low cost, robust surface flow constructed wetland using native plants, in order to test the acceptance and willingness to pay of the farmers and to see if the effluent water quality met the national standards even if operating under the lack of maintenance. Within a small catchment, 6 farmers attended a seminar series on water(shed) quality, importance of wetlands and sewage treatment options, explaining the functioning of constructed wetlands and the costs of construction. One of the farmers decided to construct a double lagoon system followed by a surface flow CW using Scirpus americanus. However, construction of the ponds occurred by the farmer himself resulting in inadequate dimensioning. The exceptionally dry summer 2008/2009 also delayed planting but by now plants have established themselves and other emergent macrophytes have followed. So far visual water quality as well as biodiversity has improved. Furthermore, farmers and technicians have become interested in the use of CW and other implementations are envisioned. Also, the legislation on dairy farm effluent is about to change which will boost the necessity for all kinds of sewage systems.


2012 ◽  
Vol 518-523 ◽  
pp. 1969-1972
Author(s):  
Xiao Fang Yue ◽  
Bo Liu ◽  
Lin Fang ◽  
Chang Kun Liu

In this paper, the performance of the constructed rapid infiltration system ( CRI ) for removal of organic pollutants of domestic sewage was investigated. The results showed that the system had higher efficiency of CODCr removal. The removal rate of CODCr was 86.1% by constructed rapid infiltration system without carbonized sludge , 91.8% with carbonized sludge. The system overcomes the disadvantage of traditional wastewater rapid infiltration land treatment system ( RI ) that the hydraulic load is low, but retains the advantages that the solution process are the low cost, the ease of processing, less energy consumption and good water quality.


Author(s):  
Audra Skaisgiriene ◽  
Pertas Vaitiekūnas ◽  
Vytenis Zabukas

The biological treatment method is widely used in Lithuania due to its high efficiency, low cost and suitability for treating various types of wastewater. After technological processes various mineral substances, such as chlorides and sulphates, get into water bodies. These substances are not removed from wastewater by the biological treatment method. The purpose of this study is to determine the concentrations of chlorides and sulphates, investigate the influence of enzyme preparations upon quality and energy consumption and assess energy changes in the trophic food chain during biological treatment. To analyse the mineral salt influence of the biooxidation process a series of laboratory tests was carried out: biochemical oxygen consumption (BOD), activated sludge concentration and other indexes. It is found experimentally that a 400 mg/1 concentration of chlorides disarranges the activity of microorganisms, and at a 700 mg/1 concentration active sludge is no longer suitable for biological treatment. Also, we investigated the effect of a ferment preparation “Roebic” on effluence of sewage treatment. In a tank with an enzyme the total amount of energy after treatment increases by 5–30 %. It is determined by calculating the accumulation of energy in an active‐sludge system that an enzyme preparation increases the energy levels of the system.


2020 ◽  
Vol 26 (3) ◽  
pp. 143-147
Author(s):  
IONEL OLARU

Many studies have been conducted for jet ejectors used in the recovery of solar energy or for their use in refrigeration systems for various industrial applications. Generally, these types of ejectors are using water as the working fluid because water have a low cost, a chemical stability and is safe to use. Naturally, other refrigerants, with large-scale application for industry, can be used. In such a type of jet ejector, besides selection of the refrigerant, the design of ejector is very important, with strongly influence to the performance, because the compression ratio depends on the geometry of the nozzle and on the geometry of the diffuser. Compared to other refrigeration systems, those with ejector have some advantages: simplicity in construction, high liability and low cost. However, it has a coefficient of performance lower than conventional systems, this limited the widespread application of ejector refrigeration systems.


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