GREY WATER RECYCLING FOR REUSE IN TOILET FLUSHING: A CASE STUDY IN THAILAND

2018 ◽  
Vol 13 (1) ◽  
pp. 73-82 ◽  
Author(s):  
Wannawit Taemthong

Grey water from washbasins represents the least polluted source of waste water in households and buildings. This research study investigated three alternatives in recycling grey water from washbasins for reuse in toilet flushing systems. Grey water was collected from the washbasins of a nine-storey university building. The water was treated employing three distinct treatment systems in order to determine the most appropriate system when reusing such water in flushing systems. The grey water treatment systems under scrutiny were composed of a sedimentation tank, a 24-hour aeration tank and a sand and carbon filtering tank, functioning in conjunction with a final sedimentation tank. The water quality from the selected treatment system had TSS, BOD5, and Turbidity measures of 1.67 mg/l, 3.33 mg/l, and 3.33 NTU, respectively. Fecal coliform bacteria and E. Coli were not found in the treated water. Efficiency measures in reducing TSS, BOD5, and Turbidity were 93%, 75%, and 91%, respectively. Fifty-five toilet users were interviewed during the experiment, sixty nine percent of which reported that the recycled water was comparable to tap water. In conclusion, this research recommends treating grey water from washbasins and reusing it in flushing systems in order to deploy water more efficiently in buildings.

Author(s):  
Shane Htet Ko ◽  
Hiroshi Sakai

Abstract Yangon was one of the first cities in Asia to establish a tap water system. However, the city's water supply infrastructure now lags far behind those of other regions as a consequence of political instability over the last six decades. The installation of disinfection facilities in the tap water system and the enactment of the Myanmar National Drinking Water Quality Standard (MNDWQS) were accomplished only recently during the short period of democratic government. Due to the lack of reliable published information, the suitability of the tap water for drinking remains unclear to city residents. The quality of tap water and bottled water in the central business district was examined to assess compliance with the MNDWQS. The results showed that 95% of tap water delivered to homes was contaminated with Escherichia coli or coliform bacteria. Only 14% of bottled water was free of E. coli and coliform contamination. The efficacy of household treatment devices was tested, and ceramic purifiers (CPs) and reverse osmosis (RO) devices were found to be highly (>99%) effective for E. coli elimination. RO devices performed better in terms of dissolved organic carbon reduction at 60% compared with 43% reduction with CPs.


2015 ◽  
Vol 737 ◽  
pp. 692-695
Author(s):  
Shu Xun Wang ◽  
Ying Xia Miao ◽  
Jian An Hao ◽  
Jing Wang ◽  
Yu Shan Zhang

The principle of domestic seawater technology is to replace fresh water by seawater. This paper introduces the features and demonstration scale of domestic seawater technology. Considering the successful seawater toilet-flushing in Hong Kong, comparison and economic analysis on the cases of seawater, recycled water and tap water are done. The result shows domestic seawater technology is an economical and efficient water saving technology.


2019 ◽  
Vol 98 (3) ◽  
pp. 237-249
Author(s):  
Yu. A. Rakhmanin ◽  
L. V. Ivanova ◽  
T. Z. Artyomova ◽  
E. K. Gipp ◽  
A. V. Zagaynova ◽  
...  

Introduction. The criteria used for the sanitary-bacteriological assessment of the quality of tap water should ensure its epidemic safety, which is important when choosing priority indicator microorganisms, quantitative determination of which will allow characterizing the risk of intestinal infections associated with water use conditions with sufficient reliability. Material and methods. Analyzed water studies for 10 years for the presence of sanitary-indicative bacteria in the water of surface water bodies in accordance with the guidelines MUK 4.2.1884. To isolate and quantify Salmonella, there were used the conventional magnesium medium and the developed nutrient medium, ready for use. The obtained data were processed using the statistical software package Statistic for Windows. Results. It has been established that E.coli can be considered as an additional indicator in order to assess recent fecal contamination. The absence of E.coli in drinking water does not guarantee the absence of other members of the family Enterobacteriaceae. Pathogenic and potentially pathogenic bacteria exhibited the greatest viability. E. coli turned out to be less stable, i.e. microorganisms, on an indication of which the system of sanitary and epidemic safety of the water use was built. In the experiments, lactose-positive coliform bacteria were established to be less resistant to the action of disinfecting agents than salmonella and potentially pathogenic bacteria, which should not be inherent to the indicator microorganism. Conclusion. Research results indicate that the absence of normalized lactose-positive fecal indicators fails to guarantee the absence of infectious agents since lactose-negative enterobacteria are unaccounted for - pathogenic and potentially pathogenic species causing intestinal infections. Therefore, in the sanitary-bacteriological control of tap water, it is more expedient to focus on the indicator glucose coliform bacteria (GKB).


2019 ◽  
Vol 14 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Banin Maghfirotin Marta ◽  
Utami Tyas ◽  
Cahyanto Muhammad Nur ◽  
Widada Jaka ◽  
Rahayu Endang Sutriswati

Consumption of probiotics is known to influence the gut microbiota. The aim of this study was to assess the effect of probiotic powder containing Lactobacillus plantarum Dad-13 on bacterial composition in the gut by examining fecal samples of school-age children in Yogyakarta, Indonesia. This is a randomized, double-blind, placebo-controlled study. A total of 40 healthy subjects were recruited for this study and were divided into two groups: placebo group and probiotic group. The placebo group consumed skim milk and the probiotic group consumed probiotic powder containing L. plantarum Dad-13 (2 × 109 CFU/g) for 65 days. The results showed that placebo intake had no significant effect on gut microbiota; however, probiotic caused a significant increase in L. plantarum and Lactobacillus population, while decreasing the population of E. coli and non-E. coli coliform bacteria by 55% and 75%, respectively and Bifidobacteria count did not change significantly. The study concluded that consumption of probiotic powder L. plantarum Dad-13 could increase propionic acid thereby decreasing the gut pH which has an effect on the microbial population.


2007 ◽  
Vol 2 (4) ◽  
Author(s):  
A. Hurlimann

This paper reports results from a study comparing perceived risk associated with various recycled water uses in two Australian locations, both in the state of Victoria: the capital city Melbourne, and Bendigo a regional urban centre. Both locations are experiencing ‘drought’, but Bendigo is experiencing this in a more acute manner. A case study is used in each location. Both case studies involve future use of recycled water in new commercial buildings. An on-line survey was used to measure attitudes to recycled water of the future occupants of both buildings. The study found perceived risk associated with 11 uses of recycled water increased as the use became increasingly personal. Interestingly, no difference in perceived risk associated with 11 uses of recycled water was found between locations. Prior experience (use) of recycled water was found to be a significant and positive factor in reducing risk perception. Various attitudinal variables were found to be significant influences on perceived risk. Results indicate that reducing perceived risk of recycled water use may increase satisfaction with its use.


2018 ◽  
Vol 36 (No. 5) ◽  
pp. 378-385
Author(s):  
Vytautas Januskevicius ◽  
Grazina Januskeviciene ◽  
Gintare Zaborskiene

The aim of this study was to investigate the possible harmful effect of Sarcocystis parasites on bovine diaphragm meat quality. Meat samples were collected from 120 bulls aged 20–24 months. Meat quality was investigated using microbiological and physico-chemical (RP-HPLC, GC) methods 48 hours after slaughter. Sarcocystis infection was associated with increased fat content, lightness L* and drip loss, and decreased ash and protein percentages. Infection also had a significant effect on the amount of amino acids (AAs), which slowly decreased as the number of sarcocysts increased. The total amount of AAs correlated with glutamic acid content (R = 0.966, P &lt; 0.05). Heavily infected samples contained significantly lower amounts of putrescine, histamine, spermine and spermidine (P &lt; 0.05) and<br /> a noticeable increase in the total count of aerobic microorganisms, but no change in the numbers of E. coli and coliform bacteria in comparison with no infected samples. Sarcocysts in beef diaphragms did not cause serious changes in the technological quality of the meat, but the biological quality of infected meat was reduced.  


2009 ◽  
Vol 89 (2) ◽  
pp. 285-293 ◽  
Author(s):  
S J Bach ◽  
R P Johnson ◽  
K. Stanford ◽  
T A McAllister

Bacteriophage biocontrol has potential as a means of mitigating the prevalence of Escherichia coli O157:H7 in ruminants. The efficacy of oral administration of bacteriophages for reducing fecal shedding of E. coli O157:H7 by sheep was evaluated using 20 Canadian Arcott rams (50.0 ± 3.0) housed in four rooms (n = 5) in a contained facility. The rams had ad libitum access to drinking water and a pelleted barley-based total mixed ration, delivered once daily. Experimental treatments consisted of administration of E. coli O157:H7 (O157), E. coli O157:H7+bacteriophages (O157+phage), bacteriophages (phage), and control (CON). Oral inoculation of the rams with 109 CFU of a mixture of four nalidixic acid-resistant strains of E. coli O157:H7 was performed on day 0. A mixture of 1010 PFU of bacteriophages P5, P8 and P11 was administered on days -2, -1, 0, 6 and 7. Fecal samples collected on 14 occasions over 21 d were analyzed for E. coli O157:H7, total E. coli, total coliforms and bacteriophages. Sheep in treatment O157+phage shed fewer (P < 0.05) E. coli O157:H7 than did sheep in treatment O157. Populations of total coliforms and total E. coli were similar (P < 0.05) among treatments, implying that bacteriophage lysis of non-target E. coli and coliform bacteria in the gastrointestinal tract did not occur. Bacteriophage numbers declined rapidly over 21 d, which likely reduced the chance of collision between bacteria and bacteriophage. Oral administration of bacteriophages reduced shedding of E. coli O157:H7 by sheep, but a delivery system that would protect bacteriophages during passage through the intestine may increase the effectiveness of this strategy as well as allow phage to be administered in the feed.Key words: Escherichia coli O157:H7, bacteriophage, sheep, environment, coliforms


Author(s):  
Pooria Ebrahimi ◽  
Stefano Albanese ◽  
Leopoldo Esposito ◽  
Daniela Zuzolo ◽  
Domenico Cicchella

Providing safe tap water has been a global concern. Water scarcity, the ever-increasing water demand, temporal variation of water consumption, aging urban water infrastructure and anthropogenic pressure on the water...


2019 ◽  
Vol 674 ◽  
pp. 439-450
Author(s):  
D. Goodwin ◽  
M. Raffin ◽  
P. Jeffrey ◽  
H.M. Smith
Keyword(s):  

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