Biological Removal of Iron from Groundwater

1991 ◽  
Vol 23 (7-9) ◽  
pp. 1437-1446 ◽  
Author(s):  
M. N. Viswanathan ◽  
B. Boettcher

Host of the soluble iron in groundwater exists in complexes with organic matter. Removal of iron, complexed with organic matter, is difficult and requires the use of a strong oxidant such as ozone, chlorine, etc. This increases capital and operating costs of water treatment plants. Iron oxidizing bacteria like Gallionellaferruginea are known to oxidize iron and derive the energy for the reduction of CO2. A biological reactor was developed, based on these principles, to remove iron from groundwater. The reactor was successful in reducing iron levels in groundwater from 2.5-3.0 mg/l to about 0.1 mg/l. It was observed that, apart from Gallionellaferruginea, Sphaerotilus spp. were also present in the reactor column. No major problems with respect to clogging of filters or the reactor column were experienced.

2011 ◽  
Vol 6 (2) ◽  
Author(s):  
Laurence Durand-Bourlier ◽  
Amandine Tinghir ◽  
Philippe Masereel ◽  
Sylvie Baig

Belgium is increasingly encountering drinking water problems because of resource scarcity and because of the quality of surface water from rivers and canal, which are often highly degraded. High organic matter concentrations are found and treated water has non-satisfying organic contents. This has a direct impact on THM formation and bacteria regrowth in the supply network. With more and more stringent regulations, organic matters concentration level in drinking water must be reduced. Nanofiltration (NF) is a suitable method for organic matter removal with reduction efficiency sometimes higher than 90 % (Orecki et al. 2004). It can be more effective than conventional technologies like activated carbon adsorption (Coté et al. 1996). This is a reason for upgrading old treatment plants by using NF treatment as a polishing step. Two drinking water treatment plants located in Eupen and La Gileppe in Belgium needed to be upgraded. These both plants treat surface water from dams and are equipped with a conventional clarification. A pilot study was carried out to compare different treatment files to remove Total Organic Carbon (TOC) and Biologically Degradable Organic Carbon (BDOC). NF process has been finally chosen. The aim of the paper is to report and discuss data supporting the choice of NF from pilot scale study and next full-scale performances of both upgraded drinking water treatment plants. The whole demonstrates the interest of NF as a suitable technology organic matter removal.


2004 ◽  
Vol 4 (5-6) ◽  
pp. 271-276
Author(s):  
D. Codiasse ◽  
Ch. Caudron ◽  
I. Baudin ◽  
M. Chouhou ◽  
C. Campos

Many water treatment plants are currently facing the challenge of removing both turbidity and organic matter at a reasonable cost. This double objective often requires high coagulant doses, resulting in high operating costs due to the increase in both reagents use and sludge production. An attractive approach to reducing operating costs while maintaining the finished water quality is to add the coagulant in a double step sequence, which is referred to as double step coagulation. In this article, bench-scale experiments were conducted to assess the impact of a double step addition of coagulant on both turbidity and organic matter removal in clarification processes. The results showed that coagulant dose required for a given turbidity target can be significantly reduced. For example, for a final turbidity of 1 NTU, the coagulant dose can be reduced by 20% with respect to the Coagulant Reference Dose (CRD), which represents 200,000 Euros per year without any additional investment on infrastructure. Following these bench scale demonstrative tests, the double step coagulation strategy was adopted at full scale by the Sidi Said Maachou Water Treatment Plant in Morocco. Operated by the Société des Eaux de l'Oum Er-rbia, this plant treats 200,000 m3/day to supply the city of Casablanca. The double step coagulation was implemented to achieve a double objective: turbidity and organic matter removal at the lowest chemical cost.


Author(s):  
Francisco J. Rodríguez-Vidal ◽  
María García-Valverde ◽  
Beatriz Ortega-Azabache ◽  
Ángela González-Martínez ◽  
Ana Bellido-Fernández

2007 ◽  
Vol 7 (18) ◽  
pp. 2651-2655 ◽  
Author(s):  
M.A. Zazouli ◽  
S. Nasseri . ◽  
A.H. Mahvi . ◽  
A.R. Mesdaghinia . ◽  
M. Younecian . ◽  
...  

2020 ◽  
Vol 15 (4) ◽  
pp. 932-946
Author(s):  
Welldone Moyo ◽  
Nhamo Chaukura ◽  
Machawe M. Motsa ◽  
Titus A. M. Msagati ◽  
Bhekie B. Mamba ◽  
...  

Abstract This study used spectroscopic methods to investigate the fate and dynamics of natural organic matter (NOM) as it traverses the treatment train at three water treatment plants (WTPs) in South Africa. The character, quantity, and removability of NOM at specific treatment stages was investigated by measuring changes in dissolved organic carbon (DOC) concentration, specific ultra-violet absorbance, UV absorbance, various spectroscopic indices, and maximum fluorescence intensity levels. A novel method of identifying and quantifying fluorescent fractions by combining synchronous fluorescence spectroscopy (SFS) and Gaussian peak fitting is presented. The dynamics of NOM removal were modeled using 2D-SFS correlation spectroscopy. Humic and fulvic substances dominated coastal plants and were the most amenable for removal by coagulation as shown by Hermanus WTP (plant H), which had a 42% DOC removal at the coagulation stage. Tyrosine-like, tryptophan-like and microbial humic-like substances were degraded or transformed concurrently at plant Flag Bushiole (FB) whereas, at plant H, fulvic-like matter was transformed first followed by tyrosine-like then humic-like matter. Through 2D-SFS, this study revealed that NOM transformation was varied as a consequence of NOM character, the type and dosage of treatment chemicals used, and WTPs operational parameters.


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