Vrishabhavathi Valley Wastewater Treatment Plant System Upgrade

Sixteen activated sludge tanks, eight secondary clarifiers, and four return pump stations were designed for the Vrishabhavathi Wastewater Treatment plant in Bangalore India. The design included tank dimensions, mechanical equipment associated with each component, pipe sizes for the piping system, and a cost estimate with a construction schedule. The activate sludge tanks were designed to be made of reinforced concrete with a mechanical air diffuser system installed for oxidation purposes. The secondary clarifiers were designed using reinforced concrete and a mechanical sweeping mechanism to scrape up the sludge as it settles to the bottom of the tank. Return pump stations were designed to transport the sludge into recirculation pipes or to a waste activated sludge stream. The treated water from the expanded facility will be discharged back into the river or transported to a tertiary treatment facility on site. The effluent will act as a source of non-potable water for local urban and agricultural use. Construction of the proposed facility will not interfere with the operation of the existing plant. This expansion to the existing facility will provide the city of Bangalore with an additional 71.33 million gallons per day of fresh, not-potable water

Towards improved 1-D settler modelling : calibration of the Bürger model and case study

Recently, Burger et al. (2011) developed a new 1-D SST model which allows for more realistic predictions of the sludge settling behaviour than traditional 1-D models used to date. However, the addition of a compression function in this new 1-D model complicates the model calibration. This study aims to report advances in the calibration of this novel 1-D model. Data of the evolution of the sludge blanket height during batch settling experiments were collected at different initial solids concentrations. Based on the linear slopes of the batch settling curves the hindered settling velocity functions by Vesilind (1968) and Takacs et al. (1991) were calibrated. Although both settling velocity functions gave a good fit to the experimental data, very large confidence intervals were found for the parameters of the settling velocity by Takacs. Global sensitivity analysis showed that it is not possible to find a unique set of parameter values for the settling function by Takacs based on experimental data of the hindered settling velocity. Subsequently, the calibrated Vesilind settling velocity was implemented in the 1-D model by Burger et al. (2011) and the parameters of the additional compression function were calibrated by fitting the model by Burger et al. (2011) to the batch settling curves. Simulation results showed that while the 1-D model by Takacs et al. (1991) underpredicted the experimental data of sludge blanket heights, the model by Burger et al. (2011) was able to predict the experimental data far more accurately. However, a global sensitivity analysis showed that no unique optimum for the combined set of hindered and compression parameters could be found

Memory Driven Pattern Formation

The diffusion equation is extended by including spatial-temporal memory in such a manner that the conservation of the concentration is maintained. The additional memory term gives rise to the formation of non-trivial stationary solutions. The steady state pattern in an infinite domain is driven by a competition between conventional particle current and a feedback current. We give a general criteria for the existence of a non-trivial stationary state. The applicability of the model is tested in case of a strongly localized, time independent memory kernel. The resulting evolution equation is exactly solvable in arbitrary dimensions and the analytical solutions are compared with numerical simulations. When the memory term offers an spatially decaying behavior, we find also the exact stationary solution in form of a screened potential.Comment: 14 pages, 12 figure

The role of solubility and critical temperatures for the efficiency of sorbitol clarifiers in polypropylene

The optical properties of polypropylene (PP) were modified by nine different sorbitol type clarifiers available commercially or synthesized in the study. The solubility of the clarifiers in PP was estimated by thermodynamic model calculations. The results showed that the solubility of these additives in PP is small, a few 1000 ppm at most. Solubility is determined by the chemical structure of the sorbitol and the heat of fusion of the latter changes solubility by at least one order of magnitude. Solubility can be estimated reasonably by the Flory-Huggins lattice theory. The morphology of most sorbitols transforms at a temperature much below their melting point upon heating. This transformation, which is accompanied by crystal perfection, seems to influence melting and solubility. A fibrillar structure forms upon the cooling of molten sorbitols, but the diameter of the fibrils is much larger than those forming in the polymer melt. The nucleating effect of the clarifier depends on solubility, but also on processing conditions. Nucleus density is related to the amount of dissolved clarifier. A close correlation was found between the Flory-Huggins interaction parameter of sorbitols and the minimum achievable haze, which can be explained with the effect of solubility and nucleus density

Поліпшення роботи освітлювачів із завислим осадом

У статті приведені результати дослідженнь можливості поліпшення роботи освітлювачів із завислим осадом при використанні розчину сульфату алюмінію, підданого магнітно-електричній активації. Показано зміну гідравлічної крупності контактного середовища освітлювача і залежність концентрації завислого осаду від швидкості висхідного потоку води.Researches results of possibility of clarifiers with the weighed deposit work improvement at the use of aluminium sulfate solution exposed to the magnetically-electric activating are considered in the article. The change of clarifiers contact dredge fall velocity and dependence of the weighed deposit concentration from water ascending stream speed are shown

Hygiena 3, a Forgotten Project for Electrolytic Water Treatment

In the interwar period, the city of Prague had to resolve the problem of treating the polluted water produced by its citizens. From 1933 - 1936 an ambitious competition was held. The idea behind the competition was to bring in new ideas and projects for a new water treatment station.Hygiena 3 was one of the projects that was submitted. It proposed a treatment procedure based on electrolytic consolidation of contaminants in water into flocks. The project was found to be inventive and interesting but too expensive and not effective. Nevertheless it was evaluated as a well developed proposal and received an award from the city

Application of citrus bioadsorbents as wine clarifiers

In recent years, reuse and recycling has taken on an increasingly important role in our society. As a result, there has been an increase in research and development of sustainable technologies. The experience acquired by the CRESCA team in the study of the revaluation of orange peels and lemon have allowed him to have a vision of this by-product as a raw material that, with the opportune treatments, can be origin of products of high added value. In this sense, very satisfactory results have been achieved for different fields of application such as: a) Agricultural: As water adsorbents, obtaining better results than conventional products (silica gel). b) Wine: As an alternative wine clarifier to products currently used (gelatin, potato protein, egg albumin, etc.) c) Treatment of wastewater with high metallic load: As heavy metal adsorbents (Ni, Cu, Pb, etc.) d) Wastewater Treatment of textile industry: as adsorbent of organic dyes. This paper proposes the use of orange peel and lemon, after being subjected to a process physicochemical, as clarifiers of wine and compared the results with those obtained with vegetable protein, gelatin and bentonitePostprint (published version

Wastewater treatment plant inspection program, fiscal year 2006 and 2007 data report

This data report includes the results from Alachua County Environmental Protection Department’s inspections of wastewater treatment plants (WWTP) within Alachua County during the 2006 and 2007 fiscal years (October 2005 – September 2007). Groundwater monitoring data provided to the Florida Department of Environmental Protection Department by the WWTP operators is included for those treatment plants that are required to submit this information (PDF has 44 pages.