Effects of Iron on Chemical Sulfide Oxidation in Wastewater from Sewer Networks

Sulfide buildup in sewer networks is associated with several problems, including health impacts, corrosion of sewer structures and odor nuisance. In recent years, significant advances in the knowledge of the major processes governing sulfide buildup in sewer networks have been made. This paper summarizes this newly obtained knowledge and emphasizes important implications of the findings. Model simulations of the in-sewer processes important for the sulfur cycle showed that sulfide oxidation in the wetted biofilm is typically the most important sink for dissolved sulfide in gravity sewers. However, sulfide emission and thereby potential hydrogen sulfide buildup in the sewer atmosphere is of particular importance in sewers constructed with large diameter pipes, in sewers constructed with steep slopes and in sewers conveying low pH wastewater. Precipitation of metal sulfides is only important when the sulfide concentration in the wastewater is low; i.e. less than 1 g S m−3.

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Chemical sulfide oxidation of wastewater - effects of pH and temperature

Water Science & Technology ◽

10.2166/wst.2004.0258 ◽

2004 ◽

Vol 50 (4) ◽

pp. 185-192 ◽

Cited By ~ 21

Author(s):

A. Haaning Nielsen ◽

J. Vollertsen ◽

T. Hvitved-Jacobsen

Keyword(s):

Rate Equation ◽

Oxidation Rate ◽

Sulfide Oxidation ◽

Chemical Oxidation ◽

Process Models ◽

Temperature Dependency ◽

Stoichiometric Coefficient ◽

Effects Of Ph ◽

Temperature Ranges ◽

Sewer Networks

In this study, the kinetics and stoichiometry of chemical sulfide oxidation of wastewater from sewer networks were investigated. Based on experiments, it was shown that the stoichiometry could be considered identical for wastewater from two sampling sites. However, the kinetics differed significantly among the wastewaters from the two sites. Effects of pH and temperature were investigated in the pH and temperature ranges 5-9 and 5-25°C, respectively. The rate of chemical sulfide oxidation could be related to the dissociation of H2S to HS-, with HS- being oxidized at a higher rate than H2S. The temperature dependency of the chemical sulfide oxidation rate was described using an Arrhenius relationship. The oxidation rate was found to double with a temperature increase of 12¡C. The stoichiometry of the chemical oxidation was not significantly affected by varying pH and temperature. Based on the experiments, a general rate equation, including a stoichiometric coefficient describing chemical sulfide oxidation in wastewater was proposed, enabling the process to be incorporated into sewer process models that can predict odor and corrosion problems.

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Model Parameters for Aerobic Biological Sulfide Oxidation in Sewer Wastewater

Water ◽

10.3390/w13070981 ◽

2021 ◽

Vol 13 (7) ◽

pp. 981

Author(s):

Asbjørn Haaning Nielsen ◽

Jes Vollertsen

Keyword(s):

Elemental Sulfur ◽

Oxygen Uptake Rate ◽

Sulfide Oxidation ◽

Oxygen Demand ◽

Model Parameters ◽

Important Process ◽

Model Concept ◽

Average Growth Rate ◽

Average Growth ◽

Sewer Networks

Sulfide related odor and corrosion are two of the major problems associated with the operation and maintenance of sewer networks. The extent of the problems is governed by several complex and interrelated processes. Sulfide oxidation is typically the most important process for sulfide removal in wastewater from aerobic gravity sewers. Despite the significance of the process, little is known about the significance of the growth of sulfide oxidizing bacteria (SOB) during the transport of wastewater. Biological sulfide oxidation in wastewater from sewers was investigated in a series of oxygen uptake rate (OUR) experiments. The experiments showed that, for oxygen nonlimiting conditions, sulfate was produced, with elemental sulfur as an intermediate. During each experiment, the activity of the sulfide oxidizing bacteria increased significantly. This was interpreted as the result of bacterial growth related to the oxidation of intermediately stored elemental sulfur. A model concept describing biological sulfide oxidation, with intermediary storage of elemental sulfur and associated growth, was developed. The model was calibrated against the experimental results. The observed average growth rate and yield constant for the SOB were determined at 1.98 d−1 and 0.17 g Chemical Oxygen Demand (COD) per g sulfur, respectively. These values correspond to reported values for mixed cultures of autotrophic SOB.

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Simulation of sulfide buildup in wastewater and atmosphere of sewer networks

Water Science & Technology ◽

10.2166/wst.2005.0077 ◽

2005 ◽

Vol 52 (3) ◽

pp. 201-208 ◽

Cited By ~ 13

Author(s):

A.H. Nielsen ◽

C. Yongsiri ◽

T. Hvitved-Jacobsen ◽

J. Vollertsen

Keyword(s):

Hydrogen Sulfide ◽

Sulfide Oxidation ◽

Sulfur Cycle ◽

Model Concept ◽

Concrete Corrosion ◽

Sulfide Production ◽

Oxidation Of Hydrogen ◽

Sulfide Precipitation ◽

Further Development ◽

Sewer Networks

A model concept for prediction of sulfide buildup in sewer networks is presented. The model concept is an extension to – and a further development of – the WATS model (Wastewater Aerobic-anaerobic Transformations in Sewers), which has been developed by Hvitved-Jacobsen and co-workers at Aalborg University. In addition to the sulfur cycle, the WATS model simulates changes in dissolved oxygen and carbon fractions of different biodegradability. The sulfur cycle was introduced via six processes: 1. sulfide production taking place in the biofilm covering the permanently wetted sewer walls; 2. biological sulfide oxidation in the permanently wetted biofilm; 3. chemical and biological sulfide oxidation in the water phase; 4. sulfide precipitation with metals present in the wastewater; 5. emission of hydrogen sulfide to the sewer atmosphere and 6. adsorption and oxidation of hydrogen sulfide on the moist sewer walls where concrete corrosion may take place.

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Effect of temperature on anoxic sulfide oxidation and denitrification in the bulk wastewater phase of sewer networks

Water Science & Technology ◽

10.2166/wst.2009.017 ◽

2009 ◽

Vol 59 (4) ◽

pp. 705-712 ◽

Cited By ~ 3

Author(s):

V. L. Mathioudakis ◽

A. Aivasidis

Keyword(s):

Municipal Wastewater ◽

Sulfide Oxidation ◽

Bulk Phase ◽

Effect Of Temperature ◽

Nitrite Accumulation ◽

Autotrophic Denitrification ◽

Batch Experiments ◽

Temperature Dependent ◽

Three Stages ◽

Sewer Networks

Artificial dosage of nitrate in sewer networks is considered as one of the most effective methods for odor and corrosion control. However, there is limited knowledge on the effect of temperature on the transformations that takes place during anoxic conditions. Thus, two groups of batch experiments were conducted to gain insight in the involved processes in bulk phase of a septic municipal wastewater. It can be concluded that sewer denitrification, in bulk phase, can be simplified in three stages. According to the experimental results, nitrate or nitrite is utilized for autotrophic denitrification with sulfide, while heterotrophic utilization is initiated after the completion of anoxic sulfide oxidation. Moreover, temperature is proved to have a significant impact on sewer denitrification kinetic profile, as it determines the extent of temporal nitrite accumulation. The temperature coefficient of each anoxic process, including sulfide oxidation, nitrate utilization and denitrification/nitrite utilization is experimentally calculated and temperature dependent equations are developed, providing the rate of all anoxic processes in bulk phase of sewer wastewater, in any given temperature.

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Выбор методов реконструкции самотечных канализационных сетей

Vodosnabzhenie i sanitarnaia tehnika ◽

10.35776/mnp.2019.12.06 ◽

2019 ◽

pp. 35-41

Author(s):

Viktor, Vasil’ev ◽

G. Morozov ◽

S. Zhukov

Keyword(s):

System Approach ◽

Block Diagram ◽

Essential Element ◽

The Self ◽

Operating Costs ◽

Reconstruction Method ◽

Existing Structures ◽

Sewage System ◽

Automation Control ◽

Sewer Networks

Реконструкция канализационных сетей становится важнейшим элементом поддержания всей системы канализации в рабочем состоянии за счет минимизации эксплуатационных затрат, увеличения срока службы трубопроводов, повышения автономности в работе системы с помощью современных средств автоматизации, контроля и анализа. Для того чтобы максимально продлить срок службы трубопроводов и не причинить вреда параллельно проложенным инженерным сетям, необходимо грамотно подбирать методы и способы реконструкции сетей, основываясь на опыте и анализе работы существующих. Рассмотрены и классифицированы основные методы реконструкции и ремонта трубопроводов. Отмечена необходимость в системной реконструкции. Разработана блок-схема, позволяющая выбрать метод реконструкции в зависимости от характера разрушения трубопровода на основании телеметрического обследования. Приведены примеры ее применения на реальных объектах. Статья написана на основе анализа технической литературы и опыта эксплуатации и проектирования канализационных сетей в Санкт-Петербурге.Rehabilitation of sewer networks becomes an essential element in maintaining the entire sewage system in running order by minimizing the operating costs, increasing the life of pipelines, increasing the self-sustainability of the system using advanced automation, control and analysis tools. In order to maximize the life of pipelines and eliminate damaging parallel laid utility networks, it is necessary to correctly choose the methods of networks rehabilitation based on the experience and analysis of the existing ones. The main methods of repair and rehabilitation of pipelines are considered and classified. The necessity for system approach to the reconstruction is noted. A block diagram has been developed that provides for choosing a reconstruction method depending on the nature of the pipeline destruction and based on the telemetry inspection. Examples of its application in the existing structures are given. The article is written on the basis of an analysis of the technical publications and experience of operating and designing sewer networks in St. Petersburg.

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Technical solutions envisaged in managing solids in combined sewer networks

Water Science & Technology ◽

10.2166/wst.1996.0220 ◽

1996 ◽

Vol 33 (9) ◽

pp. 237-244 ◽

Cited By ~ 5

Author(s):

Ghassan Chebbo ◽

Dominique Laplace ◽

André Bachoc ◽

Yves Sanchez ◽

Benoit Le Guennec

Keyword(s):

Large Scale ◽

Suspended Solids ◽

Drainage Area ◽

Bed Load ◽

Urban Drainage ◽

Combined Sewer ◽

Wet Weather ◽

Technical Solutions ◽

Dry Weather Flow ◽

Sewer Networks

Solids in combined sewer networks represent two important technical questions: - the clogging of man-entry sewers, and - pollution in urban wet weather discharges, whose main vectors are generally suspended solids. In this paper, we shall present first, curative technical solutions which avoid or remove deposits in man-entry sewers. We shall discuss the partial extraction of the largest solids; selective trapping of bed load solids, which form deposits; and the displacement of deposits using dry weather flow flushing waves. We shall then examine technical solutions to control pollution in urban wet weather discharges. This will show that decantation is an efficient means of fighting pollution. However, it is not always feasible because it involves large scale investments. Complementary methods should, therefore, be developed and used at different points in the water's passage through an urban drainage area.

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