Effectiveness of supplemental aeration and an enlarged first stage in improving RBC performance

Rotating biological contactors, a type of fixed-film wastewater treatment process, have been used extensively for treating industrial and municipal wastewaters. Several studies have indicated RBC operational problems occasioned by overloaded conditions in the first and second stages, resulting in very low dissolved oxygen levels which further result in heavy biomass growth such as Beggiatoa, thereby deteriorating process efficiency. The effectiveness of supplemental aeration and an enlarged first stage was investigated in a full-scale, four-stage RBC treatment plant having two parallel trains treating domestic and industrial dairy waste. One train was used to evaluate the effects of operational modifications, and the parallel train was used as a control. The study was conducted in two phases. In the first phase the effect of supplemental aeration alone and in the second phase the combined effect of supplemental aeration alone and use of an enlarged first stage on RBC performance were investigated. Each phase was operated separately under a range of low and high organic loading rates;The results indicate that higher removal rates can be achieved with supplemental air, regardless of the organic loading rates. The results also indicated that there is a strong relationship between organic mass loading and removal and these relationships can be used to design RBC systems. Most of the soluble COD was removed in the first stage. Dissolved oxygen levels and oxygen uptake rates were higher with supplemental air, and DO\u27s always remained above 1 mg/L. Growth of Beggiatoa was completely eliminated and thinner biofilms were established. Ammonia nitrogen removal efficiencies of 80.6 and 68.4 percent were observed at low and high organic loading rates in the presence of supplemental air. Carbonaceous substrate removal kinetics were found to be first order when using supplemental air and zero order without the air at higher organic loadings;The SCOD removal efficiencies generally increased with an enlarged first stage alone due to the reduced organic loadings in the initial stages, but removal rates observed when using supplemental aeration and an enlarged first stage were still much superior. Ammonia nitrogen removal efficiencies deteriorated when operating with an enlarged first stage, indicating preference for the plug-flow mode

EPS Producing Microorganisms from Municipal Wastewater Activated Sludge

Bacterial exopolysacchrides (EPSs) are produced by many bacteria. Nowadays there is an increasing interest in the isolation and exploitation of these polymers for industrial purposes. In general, biosynthesis of EPS varies from one strain to other strain and it depends on genes and enzymes involved in EPS production and secretion. In this study, EPS producing strains were isolated from municipal wastewater treatment plant and their potential of EPS production was evaluated. The role of EPS in sludge flocculation was also studied. Three types of EPS (LB-EPS (Loosely bound EPS), TB-EPS (Tightly bound EPS) and B-EPS (broth EPS)) were harvested and their characteristics were studied. The bioflocculation capacity of the obtained EPS was evaluated by measuring the kaolin clay flocculation activity. The LB-EPS was better than TB-EPS and B-EPS for bioflocculation

EPS Producing Microorganisms from Municipal Wastewater Activated Sludge

Bacterial exopolysacchrides (EPSs) are produced by many bacteria. Nowadays there is an increasing interest in the isolation and exploitation of these polymers for industrial purposes. In general, biosynthesis of EPS varies from one strain to other strain and it depends on genes and enzymes involved in EPS production and secretion. In this study, EPS producing strains were isolated from municipal wastewater treatment plant and their potential of EPS production was evaluated. The role of EPS in sludge flocculation was also studied. Three types of EPS (LB-EPS (Loosely bound EPS), TB-EPS (Tightly bound EPS) and B-EPS (broth EPS)) were harvested and their characteristics were studied. The bioflocculation capacity of the obtained EPS was evaluated by measuring the kaolin clay flocculation activity. The LB-EPS was better than TB-EPS and B-EPS for bioflocculation

Engineered Struvite Precipitation: Impacts of Component-Ion Molar Ratios and pH

Struvite precipitation has the potential for removing and recovering phosphorus from agricultural wastewater streams, such as concentrated animal feeding operations wastewater. However, impacts of anticipated component-ion molar ratios and potentially interfering ions are unknown as are the compounding pH relationship with respect to all potential complexes. This research experimentally investigates and mathematically models these factors. Emphasis is placed upon the composition of formed deposits and model validation with experimental data. Results show that calcium is a major interfering ion affecting the deposit composition, decreasing struvite purity. X-ray diffraction (XRD) and scanning electron microscopy + energy dispersive spectrometry were used to study the deposit structure and elemental composition. Results revealed that the precipitates formed at a pH of 8.7 have regular crystal shape, and XRD analysis confirmed that the precipitates are high-purity struvite. Higher pH (\u3e10) leads to the formation of amorphous precipitate and decreases the struvite purity in the deposits. To maximize struvite purity, the ratio of Ca to P should be less than 0.5 and the pH near 8.7

The Influence of Diet and Exercise on the Physical Health of Affected Individuals with VCP Disease

While there is no curative treatment for the Inclusion body myopathy, Paget disease of bone and/ or frontotemporal dementia (IBMPFD) disorder, it is worthwhile to investigate alternate therapies that may slow the progression of the disease and improve the quality of life in this patient population. Therefore, this study aims to evaluate the impact of diet and exercise changes on the Quality of Life questionnaire. We assessed data from the questionnaire in 30 individuals (mean age 50.86 years; range 27-65 years; 16 Males, 14 Females) that participated in the clinical study of Valosin Containing Protein (VCP) disease. Eleven affected individuals consumed a high fat/sugar diet and 15 low fat/sugar diet of 4.09±0.25 and 1.53±0.13 servings/day respectively. Eleven individuals reported not exercising and 12 reported moderate exercise of 2.44±0.74 hours/week. In this cohort we found significantly higher mean physical health domain score for all those who exercised (P=.02) and surprisingly in those who had a high fat/sugar diet (P=.01). In the high fat/sugar diet group there was a significantly greater ability to walk; greater perceived muscle strength in arms and legs (P=.03; P=.02 and P= .02 respectively). Therefore lifestyle changes with exercise training and a higher fat/ sugar diet may have a beneficial effect in affected individuals with VCP disease. Nevertheless, larger studies with further research are needed to confirm these preliminary studies before making clinical practice recommendations.

Effect of Growth Rate on Effluent Suspended Solids in Activated Sludge Systems

Bioenvironmental Engineerin

Characterization of Extracellular Polymeric Substances (Eps) Produced by \u3ci\u3eCloacibacterium normanense\u3c/i\u3e Isolated from Wastewater Sludge for Sludge Settling and Dewatering

In this study, extracellular polymeric substances (EPSs) producing strain was isolated from municipal wastewater sludge (MWWS). Growth profile and the EPS production by Cloacibacterium normanense using wastewater sludge as raw material in shake flask fermentation for 96 h were investigated. The highest concentration of S-EPS (13.0 ± 0.8 g/L) and C-EPS (0.3 ± 0.1 g/L) were attained at 48 h of fermentation. S-EPS revealed higher flocculation activity (94.2%) and dewaterability (59.9%) than other types of EPS in kaolin suspension. The dewaterability of MWWS with 2 g suspended solids (SS)/L was improved by 37.6% using 0.02 ± 0.01 g/L of S-EPS and 600 mg/L of Al2(SO4)3. The study showed a promising approach of new isolated strain to produce high concentration EPS in sludge with high flocculation activity as well as good settlin

Characterization of Extracellular Polymeric Substances (Eps) Produced by \u3ci\u3eCloacibacterium normanense\u3c/i\u3e Isolated from Wastewater Sludge for Sludge Settling and Dewatering

In this study, extracellular polymeric substances (EPSs) producing strain was isolated from municipal wastewater sludge (MWWS). Growth profile and the EPS production by Cloacibacterium normanense using wastewater sludge as raw material in shake flask fermentation for 96 h were investigated. The highest concentration of S-EPS (13.0 ± 0.8 g/L) and C-EPS (0.3 ± 0.1 g/L) were attained at 48 h of fermentation. S-EPS revealed higher flocculation activity (94.2%) and dewaterability (59.9%) than other types of EPS in kaolin suspension. The dewaterability of MWWS with 2 g suspended solids (SS)/L was improved by 37.6% using 0.02 ± 0.01 g/L of S-EPS and 600 mg/L of Al2(SO4)3. The study showed a promising approach of new isolated strain to produce high concentration EPS in sludge with high flocculation activity as well as good settlin

Adsorption of diclofenac onto different biochar microparticles: Dataset – Characterization and dosage of biochar

Due to its wide occurrence in water resources and toxicity, pharmaceuticals and personal care products are becoming an emerging concern throughout the world. Application of residual/waste materials for water remediation can be a good strategy in waste management as well as in waste valorization. Here in, this dataset provides information on biochar application for the removal of emerging contaminant, diclofenac from water matrices.The data presented here is an extension of there search article explaining the mechanisms of adsorption diclofenac on biochars(Lonappan et al., 2017[1]). This data article provides general information on the surface features of pine wood and pig manure biochar with the help of SEM and FTIR data. This dataset also provides information on XRD profiles of pine wood and pig manure biochars. In addition, different amounts of biochars were used to study the removal of a fixed concentration of diclofenac and the data is provided with this data set

Green and energy-efficient methods for the production of metallic nanoparticles

In the last decade, researchers paid great attention to the concept of “Green Chemistry”, which aims at development of efficient methods for the synthesis of nanoparticles (NPs) in terms of the least possible impact on human life and environment. Generally, several reagents including precursors, reducing agents, stabilizing agents and solvents are used for the production of NPs and in some cases, energy is needed to reach the optimum temperature for reduction. Therefore, to develop a green approach, researchers had the opportunity to investigate eco-friendly reagents and new energy transfer techniques. In order to substitute the harmful reagents with green ones, researchers worked on different types of saccharides, polyols, carboxylic acids, polyoxometalates and extracts of various plants that can play the role of reducers, stabilizers or solvents. Also, there are some reports on using ultraviolet (UV), gamma and microwave irradiation that are capable of reducing and provide uniform heating. According to the literature, it is possible to use green reagents and novel energy transfer techniques for production of NPs. However, these new synthesis routes should be optimized in terms of performance, cost, product quality (shape and size distribution) and scale-up capability. This paper presents a review on most of the employed green reagents and new energy transfer techniques for the production of metallic NPs