Removal of Nitrogen Compounds from Industrial Wastewater Using Sequencing Batch Reactor: The Effects of React Time

This study was performed to optimise the react time (RT) and study its effects on the removal rates of nitrogen compounds in a sequencing batch reactor (SBR) treating synthetic industrial wastewater. The results showed that increasing the RT from 4 h to 10, 16 and 22 h significantly improved the nitrogen compounds’ removal efficiency, it was increased from 69.5% to 95%, 75.7 to 97% and from 54.2 to 80.1% for NH3-N, NO3-N and NO2-N respectively. The results obtained from this study showed that the RT of 22 h was the optimum for nitrogen compounds removal efficiency

Public participation in solid waste management during mega festivals: A pilot study

Large festivals with over 50,000 participants have become a customary but hardly investigated practice in many countries across the world. Festivals management is increasingly being complicated because of their negative consequences such as solid waste accumulation and the destruction to the hosting city attractions. Recycling is an important process to reduce the negative consequences of the waste which public plays an extremely important role regarding its success. Therefore, this study is dedicated to explore campers’ environmental awareness and willingness to participate in the solid waste source separation during mega festivals in Kerbala city, Iraq. The outcome of a structured questionnaire survey completed by 20 camps’ managers during one mega festival showed low environmental awareness among the participants. On the other hand, the majority of the campers were willing to separate their wastes during mega festivals. These results can be invested in establishing a base for implementing a recycling scheme during such festivals

Treatment of Residential Complexes’ Wastewater using Environmentally Friendly Technology

Residential complexes discharge huge quantities of wastewater, which has a negative impact on nearby water bodies. Moreover, the treatment of this type of wastewater requires a large area, which could be a challenge as construction sites are normally limited in size. Different technologies have been used for the treatment of residential complexes’ wastewater (RCWW). Compared to the conventional wastewater treatments methods, sequencing batch reactors (SBRs) are lower cost and have smaller area requirements and sludge bulking rarely occurs. A considerable number of researchers have been optimising SBR operating conditions to gain a better removal efficiency of undesired wastewater pollutants. However, many researchers have reported bad, slow or incomplete particle settling. This study examines the impact of organic loading rate (OLR) on the effluent quality and sludge settling performance in a sequencing batch reactor. Four SBR reactors were used in this study; the working volume of each one is 5l. The reactors were operated under different glucose concentrations (750, 1000, 1250 and 1500 mg/l), constant aeration, 1.0 l/min, ±20 Cº temperature and 6 h cycle time. Each cycle of the SBR operation included Fill (30 minutes), React (240 minutes), Settle (30 minutes), Draw (30 minutes) and Idle (30 minutes). Influent and effluent samples were analysed for COD, NH3-N, NO3-N and NO2-N. In addition, the sludge volume index (SVI) and a morphological study were used to study the sludge characteristics. The SVI and morphological study results showed a direct relationship between the glucose concentration and sludge settling behaviour. The results obtained from this study, which operated for 120 days, showed that the sequencing batch reactor could biodegrade up to 93.2%, 95.2%, 94.9% and 96.5% for COD, NH3-N, NO3-N and NO2-N respectively with glucose concentration between 750 and 1250 mg/l, and a steady sludge settling performance occurred during that range

Online Monitoring of a Sequencing Batch Reactor Treating Domestic Wastewater

Domestic wastewater consists of considerable concentrations of pollutants that can boost water eutrophication if not treated before final discharge, which could damage the ecosystem and negatively affect human health. Sequencing batch reactor (SBR) technology is considered a promising biological wastewater treatment technology to address these issues. In recent years, SBR selection has increased as an effective technology for the treatment of domestic and industrial wastewaters due to its setup simplicity and ease of operation. However, many researchers have reported differences in cycle time. The importance and originality of this study is that it explores the parameters of pH, temperature, oxidation-reduction potential (ORP) and dissolved oxygen (DO) throughout the SBR cycle to predict the end of the treatment cycle. A laboratory-scale SBR was used in this study with a five-litre working volume. It was equipped with four electronic sensors (probes) to monitor the pH, ORP, temperature and DO. The SBR was operated under constant aeration, 1.0 l/min, ±12 Cº temperature and 6 h cycle time. Each cycle of the SBR operation included Fill (30 minutes), React (240 minutes), Settle (30 minutes), Draw (30 minutes) and Idle (30 minutes). Influent and effluent samples were analysed for COD, ammonia-N and nitrate-N. The pH, ORP and DO values at the end of the 6 h HRT treatment cycle were between 6.6-7.9, 147-169 mV and 4.6-6.6 mg/l respectively. The results show complete degradation of COD and nitrogen compounds was seen when the DO profile increased due to bacterial respiration. The results prove that online monitoring of SBR operating parameters could significantly predict the end of the treatment cycle, and the pH, DO and ORP profiles could be used as onsite process control parameters

Ammonia Removal using Sequencing Batch Reactor: The Effects of Organic Loading Rate

This study examines the impact of organic loading rate (OLR) on the effluent quality and sludge settling performance in a sequencing batch reactor. Four SBR reactors were used in this study; the working volume of each one is 5l. The reactors were operated under different potassium nitrate concentrations (50, 100, 150 and 200 mg/l), constant aeration, 1.0 l/min, ±20 Cº temperature and 6 h cycle time. Each cycle of the SBR operation included Fill (30 minutes), React (240 minutes), Settle (30 minutes), Draw (30 minutes) and Idle (30 minutes). Influent and effluent samples were analysed for NH3-N to determine the removal efficiency. In addition, the sludge volume index (SVI) was used to study the sludge characteristics. The results obtained from this study, which operated for 60 days, showed that the sequencing batch reactor could biodegrade up to 91.5% for NH3-N with potassium nitrate concentration between 50 and 150 mg/l, and a steady sludge settling performance occurred during that range

Old World cutaneous leishmaniasis treatment response varies depending on parasite species, geographical location and development of secondary infection

Background: In the Kingdom of Saudi Arabia (KSA), Leishmania major and L. tropica are the main causative agents of Old World cutaneous leishmaniasis (CL). The national CL treatment regimen consists of topical 1% clotrimazole/2% fusidic acid cream followed by 1–2 courses of intralesional sodium stibogluconate (SSG); however, treatment efficacy is highly variable and the reasons for this are not well understood. In this study, we present a complete epidemiological map of CL and determined the efficacy of the standard CL treatment regime in several endemic regions of KSA. Results: Overall, three quarters of patients in all CL-endemic areas studied responded satisfactorily to the current treatment regime, with the remaining requiring only an extra course of SSG. The majority of unresponsive cases were infected with L. tropica. Furthermore, the development of secondary infections (SI) around or within the CL lesion significantly favoured the treatment response of L. major patients but had no effect on L. tropica cases. Conclusions: The response of CL patients to a national treatment protocol appears to depend on several factors, including Leishmania parasite species, geographical location and occurrences of SI. Our findings suggest there is a need to implement alternative CL treatment protocols based on these parameters