Integrated faecal sludge treatment and recycling through constructed wetlands and sunflower plant irrigation

2006 ◽  
Vol 54 (11-12) ◽  
pp. 155-164 ◽  
Author(s):  
T. Koottatep ◽  
C. Polprasert ◽  
S. Hadsoi

Faecal sludge (FS) from the on-site sanitation systems is a nutrient-rich source but can contain high concentrations of toxic metals and chemicals and infectious micro-organisms. The study employed 3 vertical-flow CW units, each with a dimension of 5×5×0.65 m (width×length×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%. A solid layer of about 80 cm was found accumulated on 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 4.5×4.5 m (width×length). In the study, tap water was mixed with 20%, 80% and 100% of the CW percolate at the application rate of 7.5 mm/day. Based on a 1-year data in which 3 crops of plantation were experimented, the contents of Zn, Mn and Cu in soil of the experimental plots were found to increase with increase in CW percolate ratios. In a plot with 100% of CW percolate irrigation, the maximum Zn, Mn and Cu concentrations of 5.0, 12.3 and 2.5 mg/kg, respectively, were detected in the percolate-fed soil, whereas no accumulation of heavy metals in the plant tissues (i.e. leaves, stems and flowers) of the sunflower were detected. The highest plant biomass yield and oil content of 1000 kg/ha and 35%, respectively, were obtained from the plots fed with 20% or 50% of the CW percolate.

Author(s):  
Subin Kalu ◽  
Gboyega Nathaniel Oyekoya ◽  
Per Ambus ◽  
Priit Tammeorg ◽  
Asko Simojoki ◽  
...  

AbstractA 15N tracing pot experiment was conducted using two types of wood-based biochars: a regular biochar and a Kon-Tiki-produced nutrient-enriched biochar, at two application rates (1% and 5% (w/w)), in addition to a fertilizer only and a control treatment. Ryegrass was sown in pots, all of which except controls received 15N-labelled fertilizer as either 15NH4NO3 or NH415NO3. We quantified the effect of biochar application on soil N2O emissions, as well as the fate of fertilizer-derived ammonium (NH4+) and nitrate (NO3−) in terms of their leaching from the soil, uptake into plant biomass, and recovery in the soil. We found that application of biochars reduced soil mineral N leaching and N2O emissions. Similarly, the higher biochar application rate of 5% significantly increased aboveground ryegrass biomass yield. However, no differences in N2O emissions and ryegrass biomass yields were observed between regular and nutrient-enriched biochar treatments, although mineral N leaching tended to be lower in the nutrient-enriched biochar treatment than in the regular biochar treatment. The 15N analysis revealed that biochar application increased the plant uptake of added nitrate, but reduced the plant uptake of added ammonium compared to the fertilizer only treatment. Thus, the uptake of total N derived from added NH4NO3 fertilizer was not affected by the biochar addition, and cannot explain the increase in plant biomass in biochar treatments. Instead, the increased plant biomass at the higher biochar application rate was attributed to the enhanced uptake of N derived from soil. This suggests that the interactions between biochar and native soil organic N may be important determinants of the availability of soil N to plant growth.


2012 ◽  
Vol 610-613 ◽  
pp. 296-299
Author(s):  
Xin Jie Li ◽  
Dan Nan Jiang ◽  
Yue Jun Zhang

In order to learn the ClO2 decay behaviour in tap water, the kinetics of ClO2 decay in pure water was studied. Under the conditions of tap water treatment and keeping away from light, the effects of temperature and pH on ClO2 degradation were investigated. The results show that the ClO2 decay reaction in pure water is the first-order with respect to ClO2, the decay rate constants increase with increase in temperature or pH. At pH=6.87, the rate constants are 0.012h-1(15°C), 0.017h-1(25°C), 0.023h-1(35°C), and 0.029h-1(45°C), respectively. At 25°C, the rate constants are 0.0083h-1(pH=4.5), 0.0111h-1(pH=5.5), 0.0143h-1(pH=6.5), 0.0222h-1(pH=7.5), and 0.0351h-1(pH=8.5), respectively. The experimental data prove that ClO2 is more stable in acidic or lower temperature water than in neutral, alkalescent, or higher temperature water.


2015 ◽  
Vol 17 (1) ◽  
pp. 162-174 ◽  

<div> <p>This paper presents an assessment of the impact of uncontrolled and unscientific disposal of MSW on ground water in Dhanbad city, India. In this study, ground water quality around municipal solid waste disposal sites was investigated. Ground water quality analysis was carried out on samples collected at various distances from two disposal sites. The study has revealed that the ground water quality near dumping sites does not conform to the drinking water quality standards as per IS:10500. The impacts of indiscriminate dumping activity on ground water appeared most clearly as high concentrations of total dissolved solids, electrical conductivity, chlorides, chemical oxygen demand, and sulphates. High amount of metals like Na, K, Ca, Mg, Cd, Cu, Ni, Fe, Zn and Mn has also been detected in the groundwater samples near dumping area. Leachate characterization study also reveals high potential for groundwater contamination. Presence of feacal coliform contamination in groundwater samples indicates potential health risk for individuals exposed to this water.&nbsp;</p> </div> <p>&nbsp;</p>


2020 ◽  
Vol 10 (1) ◽  
pp. 47-55
Author(s):  
Elena I. VIALKOVA ◽  
Olga V. SIDORENKO ◽  
Ekaterina S. GLUSHENKO

Nowadays there is the problem of the effective treatment of dairy industry plants’ wastewaters. Industrial wastewaters of these plants have high concentrations of organic matters and differ significantly from domestic wastewaters. The method of intensification of dairy wastewaters treatment in Tyumen region, using probiotic «PIP Plus WATER» (Belgium) is considered in this article. The article presents the results of conducted research on the impact of the probiotic on such wastewaters indices as pH, chemical oxygen demand, anionic surfactants, ammonium, nitrites, nitrates and phosphates concentrations. The comparison among different ways of wastewater treatment with probiotics has been made. Based on obtained results technological scheme of local treatment plant of dairy industry plant has been suggested.


2021 ◽  
Author(s):  
Bernice Mawumenyo Senanu ◽  
Patrick Boakye ◽  
Sampson Oduro-Kwarteng ◽  
Divine Damertey Sewu ◽  
Esi Awuah ◽  
...  

Abstract On-site dry sanitation facilities, although cheaper than wet sanitation systems, suffer from high malodour and insect nuisance as well as poor aesthetics. The high odour deters users from utilizing dry sanitation toilet as an improved facility leading to over 20% open defecation in Sub-Saharan Africa. To address this malodour concern, this study first assessed odour levels, using hydrogen sulphide (H2S) and ammonia (NH3) as indicators, on two (2) dry sanitation facilities (T1 and T2). The potential of using biomass (sawdust, rice husk, moringa leaves, neem seeds), ash (coconut husk, cocoa husk) or biochar (sawdust, rice husk, bamboo) as biocovers to remove or suppress odour from fresh faecal sludge (FS) over a 12-day period was investigated. Results showed high odour levels, beyond and below the threshold limit for unpleasantness for humans on H2S (peak value: T1 = 3.17 ppm; T2 = 0.22 ppm > 0.05 ppm limit) and NH3 (peak value: T1 = 6.88 ppm; T2 = 3.16 ppm < 30 ppm limit), respectively. The biomasses exhibited low pH (acidic = 5-7) whereas the biochars and ashes had higher pHs (basic = 8-13). Acidic biocovers generally reduced NH3 emission significantly (12.5% to 64.8%) whereas basic biocovers were more effective at H2S emission reduction (80.9% to 96.2%). In terms of H2S and NH3 removal, sawdust biochar was the most effective biocover with odour abatement values of 96.2% and 74.7%, respectively. The results suggest that locally available waste plant-based materials, like sawdust, when converted to biochar can serve as a cost-effective and sustainable way to effectively combat odour-related issues associated with dry sanitation facilities to help stop open defecation.


2021 ◽  
Author(s):  
Min Wang ◽  
Yujue Zhou ◽  
Lin Xiang ◽  
Xiaoyang Ke ◽  
Hui Zhang ◽  
...  

Abstract Previous studies have shown that wetland plants can treat wastewater in a cost-effective and sustainable way, however, the studies on the performance of ornamental wetland plant diversity in treating urban sewage were scarce. Therefore, this study was conducted to assess and select wetland polyculture combination that was effective in urban sewage treatment in subtropical areas. We formed five combinations out of six ornamental wetland plant species including Thalia dealbata, Cyperus alternifolius, Iris pseudacorus, Lythrum sastlicaria, Nymphaea tetragona, and Zantedeschia aethiopica. The growth state and removal effects of each plant combination were systematically measured and assessed. The results indicated all the combinations exhibited remarkable total nitrogen (TN), total phosphorus (TP), ammonium nitrogen (NH­4+-N), and chemical oxygen demand chromium (CODcr) removal rate of 70.75%-77.67%, 63.86%-73.71%, 69.73%-76.85%, and 57.28%-75.69%, respectively. Additionally, pH was reduced to 7.54-8.00 in the sewage. The purification effect reached the best during 30-36th day. The comprehensive assessment showed the mixture of Thalia dealbata + Cyperus alternifolius, closely followed by Thalia dealbata + Cyperus alternifolius+ Lythrum sastlicaria, was highly effective at extracting various pollutants, and both of them could be used as favorable combinations to convert eutrophication and purify municipal wastewater. Linear regression showed that TP, TP, NH­4+-N, and CODcr. were significantly related to plant biomass, indicating that plant biomass essential indicator for screening purification plants. Our study highlighted the importance of plant diversity in biological wastewater treatment, however the competition between plants was suggested to take into consideration in future studies.


Drones ◽  
2020 ◽  
Vol 4 (3) ◽  
pp. 59
Author(s):  
Daniel Martin ◽  
Vijay Singh ◽  
Mohamed A. Latheef ◽  
Muthukumar Bagavathiannan

This study was designed to determine whether a remotely piloted aerial application system (RPAAS) could be used in lieu of a backpack sprayer for post-emergence herbicide application. Consequent to this objective, a spray mixture of tap water and fluorescent dye was applied on Palmer amaranth and ivyleaf morningglory using an RPAAS at 18.7 and 37.4 L·ha−1 and a CO2-pressurized backpack sprayer at a 140 L·ha−1 spray application rate. Spray efficiency (the proportion of applied spray collected on an artificial sampler) for the RPAAS treatments was comparable to that for the backpack sprayer. Fluorescent spray droplet density was significantly higher on the adaxial surface for the backpack sprayer treatment than that for the RPAAS platforms. The percent of spray droplets on the abaxial surface for the RPAAS aircraft at 37.4 L·ha−1 was 4-fold greater than that for the backpack sprayer at 140 L·ha−1. The increased spray deposition on the abaxial leaf surfaces was likely caused by rotor downwash and wind turbulence generated by the RPAAS which caused leaf fluttering. This improved spray deposition may help increase the efficacy of contact herbicides. Test results indicated that RPAASs may be used for herbicide application in lieu of conventional backpack sprayers.


2020 ◽  
Vol 15 (2) ◽  
pp. 506-514
Author(s):  
Niharika Sharma ◽  
Sagar Gupta ◽  
Anil Dutt Vyas

Abstract Non-sewer sanitation systems are widely implemented for treatment and management of faecal sludge (FS) and septage in developing nations. India became an open defecation free (ODF) country in 2019, with more than 90 million toilets at rural and urban level constructed to achieve this ODF status. Government of India also initiated a faecal sludge and septage management (FSSM) policy in 2017. This paper highlights the policy vision for the state of Rajasthan and predicts options for a safely managed sanitation system through exploring the fuel potential of faecal sludge generated in the city. The intended study is an attempt to valorize faecal sludge into a marketable product through determining the heat capacity of dried faecal sludge from different sources such as pit toilets, septic tanks etc. In the present work in urban Jaipur, which is already a water scarce city, various onsite sanitation systems were targeted to collect FS samples from different locations. It was observed that the FS generated has a high heating value of 13.96 MJ/kg, with total solids ranges from 7 to 9%. For a pragmatic resource recovery option, the experimental data observed is validated with a literature review.


2019 ◽  
Vol 80 (6) ◽  
pp. 1145-1154
Author(s):  
Agyemang Richard Osei ◽  
Yacouba Konate ◽  
Felix Kofi Abagale

Abstract Constructed wetland technology is an innovative engineering technique for faecal sludge (FS) management. The presence of emergent macrophytes enhances the important processes of evapotranspiration, sludge mineralisation, and contaminant reduction. Consequently, selecting a species that can withstand the difficult sludge contaminated conditions within a local context is vital. This study monitored the pollutant removal potentials and growth dynamics of Bambusa vulgaris and Cymbopogon nardus as promising macrophytes for the constructed wetland technology in the Sudano-Sahelian context. The experiment, at pilot scale, consisted of plastic reactors (27 litre) filled with filter media of sand and fine gravels at the base, and planted with the selected species. Pollutant removal efficiencies were evaluated based on differences between influent and effluent concentrations, and physiological growth parameters of plant height, number of leaves and number of plants were monitored monthly. Total annual sludge loading rate of 31.4 and 103.4 kg TS/(m2·yr) (TS: total solids) were determined for FS + wastewater (acclimatisation phase) and FS load respectively. Both species recorded appreciable pollutant removal efficiency &gt;80% for the organic (chemical oxygen demand), nutrients (PO43_P and NH4-N) and solid (total suspended solids and total volatile solids) contents. The species thus demonstrated satisfactory performance of resistance for faecal polluted wetland conditions.


2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Wilson Greya ◽  
Bernard Thole ◽  
Catherine Anderson ◽  
Flavius Kamwani ◽  
Jan Spit ◽  
...  

Off-site lime stabilisation for treating faecal sludge was assessed by undertaking small-scale (35 L) and large-scale (600 L) field trials in Blantyre, Malawi. Hydrated lime was dosed to maintain pH 10, pH 10.5, pH 11, pH 11.5, and pH 12 depending on the buffer capacity of the faecal sludge in the four replica small-scale field trials. Significant reduction of E. coli to below the detection limit of 104 CFU/100 mL within 1 hour of treatment was reported for pH > 11. Based on the small-scale findings, large-scale field trials were conducted and greater than 3 log removal of E. coli was observed under pH 12 conditions. Therefore, based on the study, off-site lime stabilisation by dosing lime in the range of 10–35% w/w (dry solid basis), depending on the buffer capacity and solids content of the sludge to maintain pH > 11, can be used to sanitise faecal sludge during emergencies, as well as for existing on-site sanitation systems.


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