scholarly journals Feasibility of Marine Microalgae Immobilization in Alginate Bead for Marine Water Treatment: Bead Stability, Cell Growth, and Ammonia Removal

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Chen-Lin Soo ◽  
Cheng-Ann Chen ◽  
Othman Bojo ◽  
Yii-Siang Hii
Keyword(s):  
Water Treatment ◽  
Alginate Bead ◽  
N Uptake ◽  
Free Cell ◽  
Ammonia Removal ◽  
Marine Microalgae ◽  
Marine Water ◽  
Immobilized Cell ◽  
Marine Microalga ◽  
Significant Difference

Sodium alginate is the most commonly used polymer matrix in microalgae immobilization for water treatment. However, the susceptibility of alginate matrixes to cation chelating agents and antigelling cation limits the use of alginates in estuarine and marine systems. Hence, the present study aims to investigate the stability of alginate bead in marine water and the feasibility of microalgae to grow when immobilized in alginate bead for marine water treatment. Different concentrations of alginate and hardening cation calcium were used to formulate beads. The beads were incubated in Guillard’s f/2 medium and shaken vigorously by using orbital shaker for 15 days. The results indicated that bead stability was enhanced by increasing alginate and CaCl2 concentrations. Subsequently, the marine microalga, Nannochloropsis sp., was immobilized in calcium alginate bead. The growth and ammoniacal-nitrogen (NH4+-N) uptake by immobilized cell were compared with free cell culture in f/2 medium. Specific growth rate of immobilized cell (0.063 hr−1) was significantly higher than free cell (0.027 hr−1). There was no significant difference on specific uptake rate of free cell and immobilized cell; but immobilized cell removed significantly more NH4+-N (82.2%) than free cell (47.3%) culture at the end of the experiment. The present study demonstrated the potential use of alginate immobilization technique in marine microalgae culture and water treatment simultaneously.

scholarly journals CONSEQUENCES OF Cu and Zn COATED UREA TO MINIMIZE AMMONIA VOLATILIZATION

2016 ◽  
Vol 78 (6-12) ◽  
Author(s):  
Saima Kalsoom Babar ◽  
Mohd Khanif Yusop ◽  
Shakeel Ahmed Babar ◽  
Aijaz Ali Khooharo
Keyword(s):  
Ammonia Volatilization ◽  
N Uptake ◽  
Soil Series ◽  
Nh3 Volatilization ◽  
N Losses ◽  
Significant Difference ◽  
Coated Urea ◽  
Positive Effect ◽  
Range Test ◽  
Cu And Zn

Nitrogen (N) losses from agricultural fields are commonly observed particularly from urea. The rate of urea hydrolysis is accelerated as it remains in conventional form and about 70% of applied urea losses in different forms to atmosphere. Ammonia volatilization is persuasive loss among all the losses from urea. Therefore to minimize ammonia (NH3) volatilization the micronutrient coated urea is applied to enhance N-efficiency and its uptake. This study is an application of micronutrient coated urea with zinc (Zn) and copper (Cu) for two soil series of Malaysia. A laboratory experiment was designed according to the force draft technique for trapping the NH3 loss. The results have manifested that the rate of ammonia volatilization was 16% from uncoated urea and 8% from coated urea with micronutrients during the first two weeks of observations. After the six weeks of observations it was perceived that the ammonia losses for both soil series were gradually decreased with time. The mean comparison by using Tukey’s range test has shown the positive effect of micronutrient coated urea in comparison with the conventional urea. However the urea coated with the combination of both micronutrients Cu and Zn has shown significant difference in contrast to the coating urea with single micronutrient. The overall results revealed the efficacy of micronutrient coated urea on both of the soil series to maximize N-uptake and reduce NH3 volatilization.

scholarly journals Effectiveness of vertical subsurface wetlands for iron and manganese removal from wastewater in drinking water treatment plants

2019 ◽  
Vol 24 (1) ◽  
pp. 135-163
Author(s):  
Jader Martínez Girón ◽  
Jenny Vanessa Marín-Rivera ◽  
Mauricio Quintero-Angel
Keyword(s):  
Drinking Water ◽  
Wastewater Treatment ◽  
Water Treatment ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Water Treatment Plant ◽  
Pilot Scale ◽  
Treatment System ◽  
Water Treatment Plants ◽  
Significant Difference

Population growth and urbanization pose a greater pressure for the treatment of drinking water. Additionally, different treatment units, such as decanters and filters, accumulate high concentrations of iron (Fe) and manganese (Mn), which in many cases can be discharged into the environment without any treatment when maintenance is performed. Therefore, this paper evaluates the effectiveness of vertical subsurface wetlands for Fe and Mn removal from wastewater in drinking water treatment plants, taking a pilot scale wetland with an ascending gravel bed with two types of plants: C. esculenta and P. australis in El Hormiguero (Cali, Colombia), as an example. The pilot system had three upstream vertical wetlands, two of them planted and the third one without a plant used as a control. The wetlands were arranged in parallel and each formed by three gravel beds of different diameter. The results showed no significant difference for the percentage of removal in the three wetlands for turbidity (98 %), Fe (90 %), dissolved Fe (97 %) and Mn (98 %). The dissolved oxygen presented a significant difference between the planted wetlands and the control. C. esculenta had the highest concentration of Fe in the root with (103.5 ± 20.8) µg/g ; while P. australis had the highest average of Fe concentrations in leaves and stem with (45.7 ± 24) µg/g and (41.4 ± 9.1) µg/g, respectively. It is concluded that subsurface wetlands can be an interesting alternative for wastewater treatment in the maintenance of drinking water treatment plants. However, more research is needed for the use of vegetation or some technologies for the removal or reduction of the pollutant load in wetlands, since each drinking water treatment plant will require a treatment system for wastewater, which in turn requires a wastewater treatment system as well.

scholarly journals Fouling Mechanisms Analysis via Combined Fouling Models for Surface Water Ultrafiltration Process

Membranes ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 149 ◽  
Author(s):  
Bin Huang ◽  
Hangkun Gu ◽  
Kang Xiao ◽  
Fangshu Qu ◽  
Huarong Yu ◽  
...  
Keyword(s):  
Water Treatment ◽  
Surface Water ◽  
Membrane Fouling ◽  
Mechanism Analysis ◽  
Surface Water Treatment ◽  
Dead End ◽  
Cake Layer ◽  
Significant Difference ◽  
Combined Models ◽  
And Control

Membrane fouling is still the bottleneck affecting the technical and economic performance of the ultrafiltration (UF) process for the surface water treatment. It is very important to accurately understand fouling mechanisms to effectively prevent and control UF fouling. The rejection performance and fouling mechanisms of the UF membrane for raw and coagulated surface water treatment were investigated under the cycle operation of constant-pressure dead-end filtration and backwash. There was no significant difference in the UF permeate quality of raw and coagulated surface water. Coagulation mainly removed substances causing turbidity in raw surface water (including most suspended particles and a few organic colloids) and thus mitigated UF fouling effectively. Backwash showed limited fouling removal. For the UF process of both raw and coagulated surface water, the fittings using single models showed good linearity for multiple models mainly due to statistical illusions, while the fittings using combined models showed that only the combined complete blocking and cake layer model fitted well. The quantitative calculations showed that complete blocking was the main reason causing flux decline. Membrane fouling mechanism analysis based on combined models could provide theoretical supports to prevent and control UF fouling for surface water treatment.

scholarly journals Bench scale study of moving bed biofilm reactor application as pre-treatment of raw water for water treatment plant (Case study: Pesanggrahan River)

2019 ◽  
Vol 270 ◽  
pp. 04009
Author(s):  
Rhefa Fauza Setiani ◽  
Setyo Sarwanto Moersidik ◽  
Sandyanto Adityosulindro
Keyword(s):  
Water Treatment ◽  
Residence Time ◽  
Treatment Process ◽  
Ammonia Removal ◽  
Biofilm Reactor ◽  
Raw Water ◽  
Moving Bed Biofilm Reactor ◽  
Moving Bed ◽  
Pre Treatment

The quality of surface water in Jakarta is on a serious polluted status. In order to reduce the Water Treatment processing load, a pre-treatment process is needed to eliminate parameters such as organic matter, ammonia, color, taste, and odor. This treatment generally uses chemical and physical processes, such as chlorination and activated carbon that produce harmful byproducts. Moving Bed Biofilm Reactor (MBBR) is one of the solutions developed to reduce the nutrient and organic levels in raw water. This study aims to improve the quality of raw water, by reducing the concentration of COD, NH3-N, Phosphate, and TSS before entering the conventional process. Reactor performance is assessed based on contaminant removal efficiency with variation of residence time (1 hour, 1.5 hours, 2 hours). The reactor is operated by using Kaldness K1 as the medium and oxygen supply of 7 L/min. The optimum residence time is 1,5 hours with the ability to remove COD, NH3-N, Phosphate, TSS 51.8% ± 0.2; 54.3% ± 0.28; 52.6% ± 0.19; and 77.7% ± 0.14 respectively. Based on the optimum residence time, the kinetics of the ammonia removal rate in MBBR takes place at zero order, with a rate constant removal of 0.0056 g/m2.day. The results showed that the higher concentration of ammonia, and organic contaminants treated, the higher the efficiency of MBBR. Apart from water quality improvement, pre-treatment process using MBBR can reduce coagulant dose from 50 mg/L to 9 mg/L, to decrease raw water turbidity from 135 NTU to 0.68 NTU before entering the coagulation-flocculation unit.

Response to phage infection of immobilized lactococci during continuous acidification and inoculation of skim milk

1994 ◽  
Vol 61 (4) ◽  
pp. 537-544 ◽  
Author(s):  
Flavia M. L. Passos ◽  
Todd R. Klaenhammer ◽  
Harold E. Swaisgood
Keyword(s):  
Steady State ◽  
Cell Concentration ◽  
Skim Milk ◽  
Viable Cell ◽  
Free Cell ◽  
Viable Cell Concentration ◽  
Immobilized Cell ◽  
Stainless Steel Mesh ◽  
Immobilized Cell Bioreactor ◽  
Column Bioreactor

SummaryA laboratory scale bioreactor was used for continuous acidification and inoculation of milk with a proteinase-negative, lactose-fermenting strain,Lactococcus lactissubsp.lactisC2S. Calcium alginate-entrapped cells were immobilized on a spiral stainless steel mesh incorporated into a column bioreactor and used to acidify and inoculate reconstituted skim milk. Characteristics of the immobilized cell bioreactor (ICB) were compared with those of a free cell bioreactor (FCB) during challenge with a virulent phage. Steady state biomass and lactate productivities were respectively 25-fold and 12-fold larger with the ICB than with the FCB. The ICB and the FCB were inoculated with the prolate phage c2 at multiplicities of infection of 0·25 and 0·02 respectively. Within 90 min of the infection, the FCB viable cell concentration dropped by five orders of magnitude and never recovered, while the plaque forming units/ml increased dramatically. In the ICB, released cells decreased immediately after infection, but subsequently increased, while the plaque forming units/ml steadily declined, indicating that phage were being washed out of the bioreactor. Productivity of FCB decreased to zero, whereas productivity of the ICB only decreased ∼ 60% and subsequently recovered to its initial steady state value.

The effect of soil tillage system on the nitrogen uptake, grain yield and nitrogen use efficiency of spring barley in a cool Atlantic climate

2014 ◽  
Vol 153 (5) ◽  
pp. 862-875 ◽  
Author(s):  
J. BRENNAN ◽  
P. D. FORRISTAL ◽  
T. McCABE ◽  
R. HACKETT
Keyword(s):  
Grain Yield ◽  
Spring Barley ◽  
N Uptake ◽  
Conventional Tillage ◽  
Soil Tillage ◽  
Reduced Tillage ◽  
Growth Stages ◽  
Significant Difference ◽  
Tillage System ◽  
Ct System

SUMMARYField experiments were conducted between 2009 and 2011 in Ireland to compare the effects of soil tillage systems on the grain yield, nitrogen use efficiency (NUE) and nitrogen (N) uptake patterns of spring barley (Hordeum vulgare) in a cool Atlantic climate. The four tillage treatments comprised conventional tillage in spring (CT), reduced tillage in autumn (RT A), reduced tillage in spring (RT S) and reduced tillage in autumn and spring (RT A+S). Each tillage system was evaluated with five levels of fertilizer N (0, 75, 105, 135 and 165 kg N/ha). Grain yield varied between years but CT had a significantly higher mean yield over the three years than the RT systems. There was no significant difference between the three RT systems. Tillage system had no significant effect on the grain yield response to fertilizer N. As a result of the higher yields achieved, the CT system had a higher NUE than the RT systems at all N rates. There was no significant difference in NUE between the three RT systems. Conventional tillage had significantly higher nitrogen uptake efficiency (NUpE) than RT A and a significantly higher nitrogen utilization efficiency (NUtE) than all three RT systems. Crop N uptake followed a similar pattern each year. Large amounts of N were accumulated during the vegetative growth stages while N was lost after anthesis. Increased N rates had a positive effect on N uptake in the early growth stages but tended to promote N loss later in the season. The CT system had the highest N uptake in the initial growth stages but its rate of uptake diminished at a faster rate than the RT systems as the season progressed. Tillage system had an inconsistent effect on crop N content during the later growth stages. On the basis of these results it is concluded that the use of non-inversion tillage systems for spring barley establishment in a cool oceanic climate remains challenging and in certain conditions may result in a reduction in NUE and lower and more variable grain yields than conventional plough-based systems.

scholarly journals Occurrence of Mycobacterium avium subsp. paratuberculosis in Untreated Water in Northern Ireland

2005 ◽  
Vol 71 (11) ◽  
pp. 7107-7112 ◽  
Author(s):  
Lynne Whan ◽  
Hywel J. Ball ◽  
Irene R. Grant ◽  
Michael T. Rowe
Keyword(s):  
Water Treatment ◽  
Northern Ireland ◽  
Mycobacterium Avium ◽  
Water Samples ◽  
Agricultural Runoff ◽  
Fecal Coliforms ◽  
Detection Methods ◽  
Catchment Areas ◽  
Significant Difference ◽  
Untreated Water

ABSTRACT Mycobacterium avium subsp. paratuberculosis is the known cause of Johne's disease of both domestic and wild ruminants and has been implicated as a possible cause of Crohn's disease in humans. The organism is shed in the feces of infected animals and can survive for protracted periods in the environment and hence could be present in catchment areas receiving agricultural runoff. A limited survey was undertaken in Northern Ireland to test for M. avium subsp. paratuberculosis in untreated water entering nine water treatment works (WTWs) over a 1-year period. Three detection methods were employed, viz., immunomagnetic separation-PCR and culture on Herrold's egg yolk medium (HEYM) and BACTEC 12B medium, the latter both supplemented with mycobactins. Of the 192 untreated water samples tested, 15 (8%) tested M. avium subsp. paratuberculosis positive by one or more of the three detection methods. M. avium subsp. paratuberculosis was successfully isolated from eight untreated water samples, three by BACTEC culture and five by culture on HEYM. Although the highest incidence of M. avium subsp. paratuberculosis was found in spring, overall, there was no statistically significant difference between the seasons. No significant correlation was found between numbers of coliforms or fecal coliforms and the presence of M. avium subsp. paratuberculosis. In general, a higher incidence of M. avium subsp. paratuberculosis was found in untreated water entering those WTWs that had a high mean water pH value over the sampling period. This work indicates the need to determine the efficacy of water treatment processes to either kill or remove M. avium subsp. paratuberculosis from untreated water and the possible risks posed by contact with recreational water sources.

scholarly journals Methane emission and methanotrophic activity in groundwater-fed drinking water treatment plants

2020 ◽  
Vol 20 (3) ◽  
pp. 819-827 ◽  
Author(s):  
Edmundas Maksimavičius ◽  
Peter Roslev
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Methane Emission ◽  
Drinking Water Treatment ◽  
Ammonia Removal ◽  
Limited Information ◽  
Gas Stripping ◽  
Sand Filters ◽  
Water Treatment Plants ◽  
Methane Oxidizing Bacteria

Abstract Groundwater for drinking water production may contain dissolved methane (CH4) at variable concentrations. Most of this important greenhouse gas is often vented to the atmosphere during primary aeration and gas stripping processes at drinking water treatment plants (DWTPs). However, limited information exists regarding emission and fate of methane at many groundwater-fed DWTPs. This study estimates emission of methane from 1,004 DWTPs in Denmark and includes data from 3,068 groundwater wells. The fate of methane and occurrence of methane oxidizing bacteria in DWTPs was examined, including the potential role in ammonia removal. Methane emission from Danish DWTPs was estimated to be 1.38–2.95 × 10−4 Tg CH4/y which corresponds to 0.05–0.11% of the national anthropogenic methane emission. Trace levels of methane remained in the drinking water after primary aeration and entered the sand filters as a potential microbial substrate. Methanotrophic bacteria and active methane oxidation was always detected in the sand filters at groundwater-fed DWTPs. Methanotrophic consortia isolated from DWTP sandfilters were inoculated into laboratory-scale sand filters and the activity confirmed that methanotrophic consortia can play a role in the removal of ammonia via assimilation and co-oxidation. This suggests a potential for facilitating the removal of inorganic constituents from drinking water using methane as a co-substrate.

scholarly journals Kinetic study of carbazole degradation by free and immobilized Thalassospira profundimaris

2021 ◽  
Vol 3 (1) ◽  
pp. 29-37
Author(s):  
Putera Nik Aiman Mustaqim Othman ◽  
Othman Inayatullah
Keyword(s):  
Kinetic Models ◽  
Food Source ◽  
Petroleum Industry ◽  
Free Cell ◽  
Agitation Speed ◽  
The Other ◽  
Immobilized Cell ◽  
Initial Concentration ◽  
Mixing Quality ◽  
Polycyclic Aromatic

Carbazole, polycyclic aromatic hydrocarbon (PAH), is a hazardous compound and a pollutant that can mainly be found in the petroleum industry. This pollutant can be treated in many ways and one of it is known as bioremediation. A method of using degrading-cell-organism, Thalassospira profundimaris, that is able to consume the pollutant as its food source and produce metabolite, harmless substance in exchange, splits into two ways which are using the cell as free cell and the other is using it as immobilized cell. There are many factors that are affecting the performance of the cell degradation. In this study, initial concentration of carbazole and agitation speed parameters have been tested and kinetic models built based on the results of this study. This study found that in term of initial concentration of carbazole, the performance of degradation cell is better on immobilized cell but not so significant based on kinetic models built. However, addition of good mixing quality enhanced the degradation performance significantly when the agitation speed is in range of 100 revolution per minute (rpm) and below.

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