A Comparison of Chemical Methods for the Control of Odours in Wastewater

Jefferson, Bruce; Hurst, A.; Stuetz, Richard M.; Parsons, Simon A.

doi:10.1205/095758202753553211

Cited by 21 publications

(13 citation statements)

References 7 publications

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“…Besides, the proportion of H 2 S in sewage at a pH higher than 8 decreases to less than 10% of dissolved sulfides (Thistlethwayte, 1972). However, Jefferson et al (2002) proposed that pH raise to levels above 9 leads to some problems such as sludge generation, ammonia gas evolution, and calcium carbonate precipitation. Therefore, ORP>50 mV and 8.5≤pH≤9 were picked as the safe range of response to evaluate the experimental results for each designed value of additional chemical.…”

Section: Addition Of Chemicals Individuallymentioning

confidence: 99%

“…Magnesium hydroxide (Mg(OH) 2 ) is used industrially as a nonhazardous alkali to neutralize acidic wastewaters and raise the pH up to 10.0. This pH level can deactivate the bacteria responsible for the acid generation, since they cannot tolerate the high pH conditions (Jefferson et al, 2002). Since Mg(OH) 2 is a strong base, increase in pH was observed.…”

Section: Addition Of Chemicals Individuallymentioning

confidence: 99%

“…It is reported as a major disadvantage that Mg(OH) 2 cannot remove the sulfide completely from the water. In such way, odor formation will occur if the pH is decreased in any consequent point in the sewage treatment process (Jefferson et al, 2002). Calcium hypochlorite (Ca(ClO) 2 ) is identified as a strong oxidizer chemical that can be used for hydrogen sulfide oxidation (Zhang et al, 2008).…”

Section: Addition Of Chemicals Individuallymentioning

confidence: 99%

“…As ultimate treatment, SRB activity can be inhibited by pH elevation using inhibitors such as NaOH, Mg(OH) 2 , Ca(OH) 2 (Nemati et al, 2001;Jefferson et al, 2002;De Lomas et al, 2005). Oxidant materials (e.g.…”

Section: Introductionmentioning

confidence: 99%

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Suppressing dissolved hydrogen sulfide in a sewer network using chemical methods

Othman¹,

Mortezania²,

Ghafari³

et al. 2011

Sci. Res. Essays

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Corrosion process and odor emission concerns caused by H 2 S are a constant focus for many sewage system municipalities, usually from the first day of system operation. This study investigates the effect of several chemicals on prohibition of H 2 S generation in sewage, where reagents were applied either individually or in combinations. Various concentrations of calcium peroxide, calcium hypochlorite, magnesium hydroxide, ferric chloride, and their combination with certain ratios were examined. Oxidation reduction potential (ORP) and pH were measured as the indicators for mitigation of H 2 S. Although both methods (adding chemicals individually or in combination) raised the ORP and pH to the safe range (that is ORP≥50 mV and 8.5≤pH≤9), experiments revealed that designed combination of chemicals resulted in more promising outcomes. The most cost effective combination was an admixture of 2 mg FeCl 3 /L and 2.5 mg Mg(OH) 2 /L with 30 min effective reaction time which could reduce the hydrogen sulfide greater than 95%. This combination is a blend for only 25% of the optimum dosage of these chemicals compared to when they were used individually. As a result, the aforementioned combination saved 12% on chemical costs compared to use of calcium peroxide as the most effective individual chemical.

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Section: Addition Of Chemicals Individuallymentioning

confidence: 99%

Section: Addition Of Chemicals Individuallymentioning

confidence: 99%

Section: Addition Of Chemicals Individuallymentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Suppressing dissolved hydrogen sulfide in a sewer network using chemical methods

Othman¹,

Mortezania²,

Ghafari³

et al. 2011

Sci. Res. Essays

View full text Add to dashboard Cite

show abstract

“…Control strategies employed in the oil industry include the elimination of sulphate from water prior to injection [19], application of biocides [20,21], and in situ removal of H 2 S from the reservoir through addition of nitrate, or a combination of nitrate and sulphide oxidizing bacteria which promotes the biooxidation and removal of sulphide [17,[22][23][24][25]. Addition of nitrate and stimulating the activity of sulphide-oxidizing bacteria has also been reported as a means to remove the sulphide from the wastewaters [26][27][28][29][30]. Souring in oil reservoirs can also be controlled through application of metabolic inhibitors such as nitrite and molybdate salts [18,[31][32][33][34].…”

Section: Introductionmentioning

confidence: 99%