On site experiments of the slanted soil treatment systems for domestic gray water

2006 ◽  
Vol 53 (9) ◽  
pp. 193-201 ◽  
Author(s):  
Tomoaki Itayama ◽  
Masato Kiji ◽  
Aya Suetsugu ◽  
Nobuyuki Tanaka ◽  
Takeshi Saito ◽  
...  

In order to make a breakthrough for the acute problem of water shortage in the world, the key words “decentralization and re-use” are very important for new sustainable sanitation systems that will be developed. Therefore, we focused on a new treatments system called “a slanted soil treatment system” which combines a biotoilet system with a domestic grey water treatment system. Because this system is a low cost and compact system, the system can be easily introduced to homes in urban areas or in the suburbs of cities in many developing countries. In this study, we performed on site experiments carried out on Shikoku Island, Japan, for several years. We obtained the following results. The slanted soil treatment system could remove organic pollutants and total nitrogen and total phosphorus in grey water effectively. Furthermore, the system performance became high in the case of the high concentration of the influent water. The nitrification reaction and denitrification reaction were speculated to exist due to aerobic zones and anaerobic zones present in the slanted soil treatment system. The slanted soil treatment system could perform for approximately 3 years with zero maintenance. The plug flow model of 1st order reaction kinetics could describe the reaction in the slanted soil treatment system. However, it is necessary to improve the system to maintain the performance in all seasons.

Water Policy ◽  
2008 ◽  
Vol 10 (2) ◽  
pp. 119-129 ◽  
Author(s):  
Duncan Mara ◽  
Graham Alabaster

To achieve the Millennium Development Goals for urban water supply and sanitation ∼300,000 and ∼400,000 people will have to be provided with an adequate water supply and adequate sanitation, respectively, every day during 2001–2015. The provision of urban water supply and sanitation services for these numbers of people necessitates action not only on an unprecedented scale, but also in a radically new way as “more of the same” is unlikely to achieve these goals. A “new paradigm” is proposed for low-cost urban water supply and sanitation, as follows: water supply and sanitation provision in urban areas and large villages should be to groups of households, not to individual households. Groups of households would form (even be required to form, or pay more if they do not) water and sanitation cooperatives. There would be standpipe and yard-tap cooperatives served by community-managed sanitation blocks, on-site sanitation systems or condominial sewerage, depending on space availability and costs and, for non-poor households, in-house multiple-tap cooperatives served by condominial sewerage or, in low-density areas, by septic tanks with on-site effluent disposal. Very poor households (those unable to afford to form standpipe cooperatives) would be served by community-managed standpipes and sanitation blocks.


1991 ◽  
Vol 24 (5) ◽  
pp. 21-32 ◽  
Author(s):  
Judith Bower Carberry

Oxidation ponds can degrade wastewaters at low cost and provide a useful biomass if rational design, operation, and sludge removal practices are carried out. Here, the design of a plug flow Algal Bacterial Clay Treatment System (ABCT) is presented on the bases of both incident sunlight and incoming BOD concentration. Results of kinetic experimental studies are presented in order to determine both optimal and limiting operational parameters. From these experiments, it appeared to be critical to limit pH diurnal variations for effective operation of the treatment system. Empirical computer models were developed to predict reactor parameter variations due to diurnal effects. A computer model based on continuous oxidation reduction potential (redox) measurements appeared to be most useful for automated computer control of variations due to diurnal effects. Chemical addition of CaCl2 facilitated algal biomass flocculation in order to prepare liquid effluents for plant discharge and to prepare biomass for possible beneficial use.


2020 ◽  
Vol 8 (5) ◽  
pp. 4488-4493 ◽  

In the present day context of urban areas in Indian climate, looking at the statistics of the operating efficiency of existing mechanically operated water treatment plants run by local governing bodies and even when huge costs are incurred in their maintenance, it is necessitated that an efficient wastewater treatment system suitable in Indian climatic conditions and that too efficient, self-operating with minimum interference and at a low-cost construction, operating and maintenance cost. Decentralized onsite and naturally operating treatment methods are much efficient, cost-effective and feasible for Indian context. In current research, Effective positioning and modeling of the non-mechanised, gravity-based wastewater treatment system is carried out at refuge floor which is coined to be proposed as “environmental floor” for G+32 storeyed residential building. Comparative analytical study for structural and seismic response of both the structures (with and without environmental floors) is performed to check feasibility of the treatment system and quantify the benefits arising from it. It is observed form obtained results that the system can be adopted as an ultimate sustainable solution for wastewater treatment in cities where otherwise a lot of unhygienic conditions prevail if centralized treatment plants are not efficiently working.


1993 ◽  
Vol 27 (1) ◽  
pp. 1-10
Author(s):  
R. F. Marks

An overview is given of the present types of sanitation systems used in both rural and urban areas in Southern Africa, with particular reference to Zimbabwe. On-site and off-site dry sanitation methods are described, including different types of pit latrines, with special reference to the Ventilated Improved Pit (VIP) Latrine. Wet systems with on or off-site disposal methods are briefly described, and details are given of two methods of off-site disposal which are widely used in Zimbabwe, viz Waste Stabilisation Ponds (WSP) and the Modified Activated Sludge (MAS) system for biological nutrient removal. The difficulties of implementing low-cost and incremental sanitation systems are mentioned, and suggestions are made of ways to overcome these difficulties.


2018 ◽  
Vol 8 (2) ◽  
pp. 165-175 ◽  
Author(s):  
Duncan Mara

Abstract We argue that, if the sanitation target of the Sustainable Development Goals (universal access to ‘safely-managed’ sanitation by 2030) is to have any chance of success, then a community-sensitive top-down planning approach has to be adopted for sanitation provision in high-density low-income urban areas in developing countries, as ‘bottom-up’ planning is much more time-consuming and not yet successfully proven at scale. In high-density low-income urban areas, there is only a limited choice for safely-managed sanitation: (i) simplified/condominial sewerage (which becomes cheaper than on-site sanitation systems at the relatively low population densities of 160–200 people per ha), (ii) low-cost combined sewerage (if it is cheaper than separate simplified sewerage and stormwater drainage), (iii) community-managed sanitation blocks, and (iv) container-based sanitation (the last two of which are suitable, especially in slums, when neither simplified sewerage nor low-cost combined sewerage is affordable or technically feasible). These four sustainable sanitation options are as scalable in developing countries as conventional sewerage has been in industrialized countries.


2020 ◽  
Vol 17 (1) ◽  
pp. 41
Author(s):  
UMMU SHOLEHAH MOHD NOR

High residential living in Malaysia has not been widely given a significant emphasises in literature despite its increasing scale and significance in the real estate market. The significance of high rise is mainly due the increasing rate of migration from rural to urban. It is estimated a total of 77.2 percent of the Malaysian population lived in urban areas in 2020. Approximately, 30 percent of this urban population lives in strata housing. These percentages are predicted to continue to increase in the future. The emergence of high residential building has been argued as confronting various problems which has considerable impact on this life style. Satisfaction is an important outcome of living in one’s dwelling, although it is not the only consideration. High residential building in Malaysia encountered numerous problems in term of management aspects, legislation aspects, and residents’ satisfaction. The purpose of this paper is to investigate the tenants’ satisfaction living in high residential buildings in Klang Valley. The questionnaires survey is conducted amongst 276 tenants at low cost and medium cost HRB using random sampling in HRB located at areas under jurisdiction Dewan Bandaraya Kuala Lumpur (DBKL), Majlis Bandaraya Subang Jaya (MBSJ), Majlis Bandaraya Shah Alam (MBSA), Majlis Bandaraya Subang Jaya (MBSJ), Majlis Perbandaran Selayang (MPS) and Majlis Perbandaran Ampang Jaya (MPAJ). The result from this study shows that tenant in medium cost residential building are more satisfied in term of facilities and management as compared to tenants in low cost residential building. Tenants also not disclosed to the existing act and procedure related to high residential building. In conclusion, this study suggested the Local Authority to emphasise the role of tenant. These recommendation hopefully will increase the level of satisfaction amongst the residents in HRB.


2006 ◽  
Vol 1 (2) ◽  
Author(s):  
E. v. Münch ◽  
G. Amy ◽  
J. F. Fesselet

This paper describes the potential of ecological sanitation (ecosan) to provide sustainable excreta disposal in emergency situations and in peri-urban areas or slums in developing countries. At the present time, pit latrines are the most common form of excreta disposal both for emergency situations and in low-income peri-urban areas or slums. Although not intended to be a long-term solution, pit latrines provided during emergencies are often used for a long time (more than six months to years). This practice is not sustainable if the area is prone to flooding or there are soil conditions that allow groundwater pollution in areas where groundwater is used for drinking water, to name but two of the main factors. We propose eight criteria for the applicability of ecosan based on analysis of three case studies representing different types of emergency situations. The two most important criteria are awareness and expertise in ecosan within the aid agencies, and availability of standardised, lightweight toilet units that are quick to assemble and easy to transport (e.g. container for faeces, and urine diversion squatting pan made of impact-resistant molded polypropylene). Such toilets could be moved to, or replicated in, other areas in need after the emergency (peri-urban areas or slums). This would provide benefits for Millennium Development Goals achievements (targets on hunger, child mortality, sanitation and slum dwellers) at lower cost than conventional sanitation systems. Costs for sanitation systems should be compared based on the entire system (toilet, transport, treatment, reuse in agriculture), using Net Present Value analysis for capital, and operating and maintenance costs.


Chemosphere ◽  
2021 ◽  
Vol 274 ◽  
pp. 129689
Author(s):  
Jianpei Feng ◽  
Xiaolei Zhang ◽  
Guan Zhang ◽  
Ji Li ◽  
Wei Song ◽  
...  

Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 179
Author(s):  
Said Munir ◽  
Martin Mayfield ◽  
Daniel Coca

Small-scale spatial variability in NO2 concentrations is analysed with the help of pollution maps. Maps of NO2 estimated by the Airviro dispersion model and land use regression (LUR) model are fused with measured NO2 concentrations from low-cost sensors (LCS), reference sensors and diffusion tubes. In this study, geostatistical universal kriging was employed for fusing (integrating) model estimations with measured NO2 concentrations. The results showed that the data fusion approach was capable of estimating realistic NO2 concentration maps that inherited spatial patterns of the pollutant from the model estimations and adjusted the modelled values using the measured concentrations. Maps produced by the fusion of NO2-LCS with NO2-LUR produced better results, with r-value 0.96 and RMSE 9.09. Data fusion adds value to both measured and estimated concentrations: the measured data are improved by predicting spatiotemporal gaps, whereas the modelled data are improved by constraining them with observed data. Hotspots of NO2 were shown in the city centre, eastern parts of the city towards the motorway (M1) and on some major roads. Air quality standards were exceeded at several locations in Sheffield, where annual mean NO2 levels were higher than 40 µg/m3. Road traffic was considered to be the dominant emission source of NO2 in Sheffield.


2021 ◽  
pp. 096739112110245
Author(s):  
Amrita Sharma ◽  
PP Pande

It has been observed that acrylate monomers are very difficult to polymerize with the low cost nitroxide catalyst 2,2,6,6-tetramethylpiperidinyl-1-oxyl (TEMPO). Therefore, costly acyclic nitroxides such as N-tert-butyl-N-(1-diethylphosphono-2,2-dimethyl)-N-oxyl, (SG1), 2,2,5-Trimethyl-4-phenyl-3-azahexane-3-nitroxide (TIPNO) and TIPNO derivatives have to be used for the polymerization of the acrylic acid derivatives. There are very few reports on the use of TEMPO-derivatives toward the polymerization of n-butyl acrylate. Generally different reducing agents viz. glucose, ascorbic acid, hydroxyacetone etc. have been used to destroy excess TEMPO during the polymerization reaction. The acrylate polymerizations fail in the presence of TEMPO due to the strong C–O bond formed between the acrylate chain end and nitroxide. To the best of our knowledge, no literature report is available on the use of TEMPO without reducing agent or high temperature initiators, toward the polymerization of n-butyl acrylate. The present study has been carried out with a view to re-examine the application of low cost nitroxide TEMPO, so that it can be utilized towards the polymerization of acrylate monomers (e.g. n-butyl acrylate). We have been able to polymerize n-butyl acrylate using the nitroxide TEMPO as initiator (via a macroinitiator). In this synthesis, a polystyrene macroinitiator was synthesized in the first step from TEMPO, after this TEMPO end-capped styrene macroinitiator (PSt-TEMPO) is used to polymerize n-butyl acrylate monomer. The amount of macroinitiator taken was varied from 0.05% to 50% by weight of n-butyl acrylate monomer. The polymerization was carried out at 120°C by bulk polymerization method. The experimental findings showed a gradual increase in molecular weight of the polymer formed and decrease in the polydispersity index (PDI) with increase in amount of PSt-TEMPO macroinitiator taken. In all experiments conversion was more than 80%. These results indicate that the polymerization takes place through controlled polymerization process. Effect of different solvents on polymerization has also been investigated. In the following experiments TEMPO capped styrene has been used as macroinitiator leading to the successful synthesis of poly n-Butyl acrylate. It has been found that styrene macroinitiator is highly efficient for the nitroxide mediated polymerization, even in very small concentration for the synthesis of poly n-butyl acrylate. High concentration of macroinitiator results in the formation of block copolymers of polystyrene and poly ( n-butyl acrylate) viz. polystyrene-block-poly-( n-butyl acrylate). The use of TEMPO toward controlled polymerization is of much importance, because it is the nitroxide commercially available at the lowest cost.


Sign in / Sign up

Export Citation Format

Share Document