Biological Purification Of Wastewater Research Articles

Research on an eco-safe filtration plant for wastewater treatment made of natural raw materials

Purpose. To develop a new eco-safe filtration plant for wastewater treatment based on natural and secondary raw materials, which will allow rational use of natural resources with further mathematical modeling of hydrodynamics of mixing treated wastewater in bioponds to predict removal of residual concentrations from the filter. Methodology. A complex of modern methods of theoretical and experimental research was used to solve the tasks. Concentration of pollutants was determined using methods of atomic adsorption spectroscopy, titrimetry and gravimetric methods, as well as pyrometric analysis. A laboratory installation was created, which included a receiving tank, a filter column, and a tank for collecting purified wastewater. Prediction of distribution and mixing of treated effluent in bioponds was carried out using mathematical and computer software. Findings. An environmentally safe filtration plant (containing sand, fallen leaves of linden, poplar, and plastic residues separated by a polymer mesh) was created to purify wastewater from suspended substances and nitrates. Kinetics of changes in concentration of suspended solids and nitrates in urban wastewater were studied. When using the filtration plant, concentration of suspended solids decreased by 85–92 %. Concentration of nitrates in purified water processed with such a plant is reduced from 12 to 0.25–0.05 mg/dm3. A mathematical model concerning distribution of purified water in a biopond was obtained, which allows predicting possible migration distributions of residual concentrations in purified water during its natural movement downstream. Originality. For the first time, influence of the species origin of fallen leaves on the performance indicators of wastewater filtration plant of urban sewage treatment constructions was investigated, which made it possible to substantiate a new way of disposal of this type of waste. For the first time, it was established that wastewater treatment using an eco-safe filtration plant based on natural and secondary raw materials, containing layers of sand, fallen oak, linden, and poplar leaves, gives an opportunity to reduce contents of suspended solids in wastewater by 1.5 times of the maximum permissible concentration; and such treatment also reduces concentration of nitrates by 4 times from the initial level. Pollutants from wastewater are mechanically fixed in pockets (microcracks, cracks) of fallen leaves, formed during drying of leaves, which is explained by hardening of intercellular spaces with formation of a specific geometry of holes. For the first time, mathematical modeling of purified wastewater movement in a biological pond with a complex geometry was performed, which allows estimating the concentration of the pollutant at its outlet from the pond. Practical value. The created environmentally safe wastewater filtration plant gives an opportunity to perform not only filtering, but also an effective biological purification of wastewater from nitrates on the surface of layers of fallen leaves. The wide use of the proposed installation will allow attracting plastic of polyethylene bottles used in everyday life as a secondary raw material. Based on the proposed mathematical model of movement of purified liquid containing residual concentrations of pollutants, it is possible to carry out qualitative forecasting and optimization of the process of cascade wastewater treatment at industrial and economic enterprises.

An analysis of the influence of the biofilm heterogeneity on the effectiveness of organic pollution removal in bioreactors

A mathematical model of biological purification of wastewater from organic pollutants in the conditions of an aeration tank with a fixed biocenosis (biofilm of microorganisms) is presented. At the same time the peculiarities of the formation and modeling of a complex heterogeneous stratified structure of a biofilm with variable processes and parameters along its thickness are considered and taken into account on in particular the processes of mass transfer and concentration of microorganisms. It shown that the treatment processes in heterogeneous stratified biofilm are designated by the effective diffusion coefficient which is depended on the pollutions concentration. Owing to that the pollutions concentration is changing of along the biofilm thickness and increase from the surface to the biofilm bottom the decreasing of the effective diffusion coefficient is observed. On the base of the provided experimental investigations the change of the effective diffusion parameter along the biofilm thickness may be specified according to linear law. The quantity criteria of the first and zero order kinetic and Monod equation were used in the practical calculations. Ascertain that the substrate removal have a place on the early part of the biofilm which amounts to 20–25% from the its full thickness. On the base of the created biofilm model of the heterogeneous-stratified structure the comparative analysis and valuation of the different investigations of the pollutions removal during the treatment processes at using of the homogeneous and heterogeneous structure of the biofilm were treated. It was designated that the pollutions removal effectiveness depends on the biofilm features. So at the some main parameters the homogeneous and stratified biofilms indicate almost the same microbial activity and the difference depends on the effective diffusion coefficient on the biofilm output. In the dependence on the hydrodynamic conditions of the treatment processes the homogeneous biofilm activity may be lower, higher or similar one of the stratified biofilm. Heterogeneous biofilm has the lower activity near the biofilm bottom at the high values of the effectiveness coefficient than the homogeneous one at the average values of this coefficient and the substrate against of the which the microorganisms growth is depended on to penetrate more in depth in stratified biofilm than in homogeneous one.

Physiology of microalgae and their application to sustainable agriculture: A mini-review.

Concern that depletion of fertilizer feedstocks, which are a finite mineral resource, threatens agricultural sustainability has driven the exploration of sustainable methods of soil fertilization. Given that microalgae, which are unicellular photosynthetic organisms, can take up nutrients efficiently from water systems, their application in a biological wastewater purification system followed by the use of their biomass as a fertilizer alternative has attracted attention. Such applications of microalgae would contribute to the accelerated recycling of nutrients from wastewater to farmland. Many previous reports have provided information on the physiological characteristics of microalgae that support their utility. In this review, we focus on recent achievements of studies on microalgal physiology and relevant applications and outline the prospects for the contribution of microalgae to the establishment of sustainable agricultural practices.

Biological treatment of industrial and domestic wastewater of a brewery in Uzbekistan

During the period of water shortage in the Republic, modern resource-saving irrigation methods and the use of purified and industrial waters and their reuse in irrigation is an urgent problem in ecology. Among the methods for treating industrial wastewater in a cheaper, cost effective way is the biological treatment method. It is the study of the effectiveness of biological treatment of industrial wastewater from primary winemaking using selected strains of aquatic plants (pistia). The object of wastewater research is selecting a Pistia algae strain, carrying out biochemical, hydrochemical analyses of wastewater before and after treatment, and the chemical composition of the Pistia algae biomass. All studies were carried out according to the standard studies of UzGOST for waste and drinking water and algological methods used by the Institute of Botany of ANRUz, State Enterprise "Institute GIDROINGEO", etc. The efficiency of biological purification of wastewaters of primary winemaking by higher aquatic plants of the pistia was established. With the help of the research carried out, the wastewater treatment of the food plant, in particular, the Kibray wine station with the Pistia algae, was established: the optimal parameters of growth, development and purification capacity of pistia algae were established for various variants of experiments and wastewater samples; designed and assembled a semi-industrial plant for biological wastewater treatment of the Kibray wine station and carried out work on industrial wastewater treatment. Wastewater from the Kibray wine station contains organic compounds, namely yeast sediments, proteins, fats, carbohydrates, fiber, which are food for Pistia algae. Pistia biomass obtained after cultivation in wastewater after sterilization can be used as feed in livestock and poultry farming, as it contains a large number of proteins, fats and carbohydrates.

Multifaceted roles of microalgae in the application of wastewater biotreatment: A review.

Microalgae have become imperative for biological wastewater treatment. Its capability in biological purification of wastewaters from different origins while utilizing wastewater as the substrate for growth has manifest great potentials as a sustainable and economical wastewater treatment method. The wastewater grown microalgae have also been remarked in research to be a significant source of value-added bioproducts and biomaterial. This paper highlights the multifaceted roles of microalgae in wastewater treatment from the extent of microalgal bioremediation function to environmental amelioration with the involvement of microalgal biomass productivity and carbon dioxide fixation. Besides, the uptake mechanism of microalgae in wastewater treatment was discussed in detail with illustrations for a comprehensive understanding of the removal process of undesirable substances. The performance of different microalgae species in the uptake of various substances was studied and summarized in this review. The correlation of microalgal treatment efficacy with various algal strain types and the bioreactors harnessed for cultivation systems was also discussed. Studies on the alternatives to conventional wastewater treatment processes and the integration of microalgae with accordant wastewater treatment methods are presented. Current research on the biological and technical approaches for the modification of algae-based wastewater system and the maximization of biomass production is also reviewed and discussed. The last portion of the review is dedicated to the assertion of challenges and future perspectives on the development of microalgae-based wastewater treatment technology. This review serves as a useful and informative reference for readers regarding the multifaceted roles of microalgae in the application of wastewater biotreatment with detailed discussion on the uptake mechanism.

The use of higher aquatic vegetation for airports wastewater final purification

It has been shown that with air transportation rise it is necessary to increase the efficiency of storm and wastewater purification from the territory of the airports and other air enterprises. It is suggested to use higher aquatic vegetation to protect the environment from airborne pollutants into natural water reservoirs. For further step of final cleanup it is proposed to use aquatic hyacinth – Eichornia. The rationalization for the plant selection is provided, its essential characteristics and the way for extracting pollutants out of the aquatic environment during the metabolism process are described. The technique of experiments on determining the effectiveness of biological wastewater purification within the conditions of the central part of the country is discussed in terms of Moscow region. The measurement results of suspended materials and petrochemicals concentrations in water before and after purification in sediment ponds are presented. The effectiveness of biological purification is shown. The possibility of using water hyacinth for purification of some superficial water reservoirs is also outlined. It is recommended all the year round to use protecting constructions (covers) in open purification plants, then under protected conditions metabolism processes can proceed in the rhizome, stems and foliage of the vegetation even in the autumn-winter period. It is proposed to recycle the used biomass for commercial purposes as a livestock fodder additive under the certain conditions that have been defined. The algorithm of preserving seedlings in the cold season and their subsequent planting in water reservoirs in spring is discussed. It is economically feasible to use biological final purification by aquatic hyacinth but observing the unusual environmental safety measures that have been formulated is required. Practicability of further prospective work on producing specialized ecosystems involving higher aquatic vegetation for nature-like integrated purification of certain types of wastewater was underlined.

Co-cultivation of fungal-microalgal strains in biogas slurry and biogas purification under different initial CO2 concentrations

The effects of five different microalgae-fungi on nutrient removal and CO2 removal were investigated under three different CO2 contents (35%, 45% and 55%). The results showed that the highest nutrient and CO2 removal efficiency were found at 55% CO2 by cocultivation of different microalgae and fungi. The effect of different initial CO2 concentration on the removal of CO2 from microalgae was significant, and the order of CO2 removal efficiency was 55% (v/v) >45% (v/v) >35% (v/v). The best nutrient removal and biogas purification could be achieved by co-cultivation of C. vulgaris and G. lucidum with 55% initial CO2 content. The maximum mean COD, TN, TP and CO2 removal efficiency can reach 68.29%, 61.75%, 64.21% and 64.68%, respectively under this condition. All highest COD, TN, TP and CO2 removal efficiency were more than 85%. The analysis of energy consumption economic efficiency revealed that this strategy resulted in the highest economic efficiency. The results of this work can promote simultaneously biological purification of wastewater and biogas using microalgal-fungal symbiosis.

Optimization of the process of anaerobic-aerobic purification of waste waters of food production using the spatial separation of stages

The advanced energyand resource saving technologies for purification of industrial waste waters from the food production include both anaerobic biotechnologies, and the combined ones, which include anaerobic and aerobic purification steps. They possess such advantages as economic efficiency, high purification efficiency, minimal formation of excess sludge and ability to obtain alternative energy carrier - biogas. The aim of this investigation was to perform optimization of the process of anaerobic-aerobic biological purification of wastewaters from the milk treatment enterprise. During our investigation we have studied relations between the efficiency of the process of anaerobic-aerobic biological purification of wastewaters of the milk treatment enterprise and specific organic load. We investigated influence of the spatial separation of the anaerobic step of purification with directed succession of the microbial community, which performs the sequence of destruction of the organic compound on the process efficiency. It was shown, that the preliminary anaerobic purification of wastewaters from the milk treatment enterprise allows one to significantly reduce organic load at the aerobic stage of the purification facilities and remove up to 85% of the organic compound. With increase of the specific organic load from 1.4 up to 2.8 kg COD·m -3·days-1 we see a drastic improvement of the efficiency characteristics both for anaerobic and aerobic stages. The redox-potential of the fermentation medium depends on the metabolitic activity of the microbial community and might be used as an efficiency characteristics for destruction of the organic compound at the anaerobic stage, and as an indicator for the oxygen saturation of the medium at the aerobic stage of purification.

Exploring correlation between hydrobiological indicators of aeration tanks and the concentration of phosphates in purified wastewaters

The results of measuring chemical and hydrobiological indices of wastewater in real conditions of the sewage treatment plant of DP “Chernihivvodokanal» (Ukraine) were analyzed, and coefficients of correlation between phosphates concentration after biological purification of wastewater and the hydrobiological indices were calculated. It was established that the informativeness of indices as for the quality of the process of water purification from phosphates decreases in the series: the number of the hydrobiont species CSW – silt volume – the silt index – silt dose; correlation coefficients vary from К cor. =–0,39381 to К cor. =–0,0485. Using the method of fluctuation smoothing with the help of SMA – simple moving average – we identified the trend: the influence of season on the number of hydrobionts and phosphates concentration in wastewater. A change in phosphates concentration in the wastewater purified by biological way occurs mainly simultaneously in antiphase to the change in the number of hydrobiont species, characteristic for satisfactory performance of silt. The use of obtained data allows giving preference in the analysis of the course of the process to one or several indices that would contribute to operational control of purification process.

Novel approach for the ammonium removal by simultaneous heterotrophic nitrification and denitrification using a novel bacterial species co-culture.

Agricultural activities lead excessive emission of ammonia nitrogen in the environment and can profoundly interfere the equilibrium of the natural ecosystems leading to their contamination. Actually, the biological purification of wastewaters is the most adopted technique thanks to its several advantages such as high performance and low energy consumption. For this reason, two novel strains of Alcaligenes sp. S84S3 and Proteus sp. S19 genus were isolated from an activated sludge and applied in the treatment of ammonium and nitrite in aqueous solution. Under the optimum operating conditions of temperature (30 °C), pH (7), carbon substrate (2 g/L of glucose) and duration of incubation time (69 h), the strain Alcaligenes sp. S84S3 could oxidize 65% of the ammonium as high as 272.72 mg-NH4(+)/L. Moreover, during 48 h, the nitrate reduction rate performed by the strain Proteus S19 was about 99 % without production of nitrite intermediate (negligible concentration). Moreover, the coculture of the strains Alcaligenes sp. S84S3 and Proteus sp. S19 could eliminate 65.83% of the ammonium ions without production of toxic forms of nitrogen oxides during a short time of incubation (118 h) at the same operational conditions with providing the aeration in the first treatment phase. The coculture of our isolated strains is assumed to have a good potential for nitrification and denitrification reactions applied in the treatment of wastewater containing ammonium, nitrite and nitrate. As a result, we can consider that the mixed culture is a practical method in the treatment of high-strength ammonium wastewater with reducing of sludge production.

New Technologies in Intensification of Biological Removal of Aniline from Wastewater

Microbiological and hydrogeological analysis of active sludge of biological treatment facilities of the enterprise for production of aromatic amines is performed. It is shown that traditional purification methods of industrial wastewater do not make it possible to attain the required purification quality of wastewater. It is proposed to improve the design of biological treatment facilities at enterprises of organic synthesis by means of their replacement for a new in principle complex of continuous biological purification of industrial wastewater developed at OJSC “NIPIEP” (Orenburg). The operating principle of proposed apparatuses for biological purification of wastewater is based on the methods of continuous cultivation of active sludge microorganisms both in anaerobic and aerobic conditions. Sectioning the process of biological purification and the use of microbubble aerators made of sintered titanium powder and biotechnologies with rapidly growing aboriginal microorganisms immobilized on an inert biological carrier makes it possible to attain almost complete aniline destruction.

Reduction of Organic and Inorganic Pollutant from Waste Water by Algae

Recently, algae have become significant organisms for biological purification of wastewater since they are able to accumulate plant nutrients, heavy metals, pesticides, organic and inorganic toxic substances and radioactive matters in their cells/bodies. Biological wastewater treatment systems with micro algae have particularly gained importance in last 50 years and it is now widely accepted that algal wastewater treatment systems are as effective as conventional treatment systems. These specific features have made algal wastewaters treatment systems an significant low-cost alternatives to complex expensive treatment systems particularly for purification of municipal wastewaters. By this method 70 % of biological oxygen demand, 66 % of chemical oxygen demand, 71 % total nitrogen, 67 % of phosphorus, 54 % volatile solid and 51 % of dissolved solid was reduced

Reduction of Organic and Inorganic Pollutant from Waste Water by Algae

Recently, algae have become significant organisms for biological purification of wastewater since they are able to accumulate plant nutrients, heavy metals, pesticides, organic and inorganic toxic substances and radioactive matters in their cells/bodies. Biological wastewater treatment systems with micro algae have particularly gained importance in last 50 years and it is now widely accepted that algal wastewater treatment systems are as effective as conventional treatment systems. These specific features have made algal wastewaters treatment systems an significant low-cost alternatives to complex expensive treatment systems particularly for purification of municipal wastewaters. By this method 70 % of biological oxygen demand, 66 % of chemical oxygen demand, 71 % total nitrogen, 67 % of phosphorus, 54 % volatile solid and 51 % of dissolved solid was reduced

Introduction of biochemical wastewater purification at OOO Mechel-Koks (stage I)

Systems for mechanical and biological wastewater purification have been introduced at OOOMechel-Koks. This represents the first stage of a two-stage project to introduce biochemical purification. Results obtained in the adjustment and debugging of the systems are presented.

COMPARATIVE ANALYSIS OF AERATORS FOR WASTEWATER PURIFICATION AND UNIFIED AERATION CRITERIA

The article shows that it is only reasonable to compare and choose aerators for biological wastewater purification using a set of unified aeration criteria, based on oxygen mass transfer coefficient, oxidizing capacity and aeration efficiency.

Experimental study of wave gas dispersers in liquid

A new type of device for dispersing gas in liquid, a wave disperser, is developed and studied. Its functioning is based on the utilization of pressure pulses generated by waves propagating from a generator of hydrodynamic vibrations. The purpose of the work is to reduce the gas bubble size and the energy losses to dispersion compared to the known disperser types. This is important for many chemical technologies, systems of biological purification of wastewater, and chlorination and ozone treatment of tap water.

Heterofazowe termoplastyczne kompozycje polimerowe modyfikowane odpadami gumowymi

The results of own research concerning new polymeric compositions based fully on secondary materials, obtained by physical modification, were presented. Recycled thermoplastics - PE-LD or PVC (Table 1) - were used as polymer matrix. Ground vulcanized rubber wastes of tires as well as thermally modified phosphogypsum (Table 2 and 3) or activated chalk were used as the fillers. Mechanical properties of such compositions (Table 4 and 5) and possibilities of their practical applications, with utilization of specific properties coming from the materials used, were discussed. It has been found that porous hoses made of such compositions show the properties qualifying them for use in the irrigation systems (Fig. 6). The compositions discussed can be also used as the fillers of noise damping screens (Fig. 7), fillers of columns for biological waste-water purification (Fig. 8) as well as for producing of the traffic safety devices or floorings.

Determination of the optimum dose of activated sludge in the aeration tank-mixer system in biological purification of wastewaters

Determination of the optimum dose of activated sludge in the aeration tank-mixer system in biological purification of wastewaters

5374353 Aeration train and aeration apparatus for biological purification of wastewater : Murphy D Thomas Kihei, HI, 96753, United States

5374353 Aeration train and aeration apparatus for biological purification of wastewater : Murphy D Thomas Kihei, HI, 96753, United States

5374353 Aeration train and aeration apparatus for biological purification of wastewater : Murphy D Thomas Kihei, HI, 96753, United States

5374353 Aeration train and aeration apparatus for biological purification of wastewater : Murphy D Thomas Kihei, HI, 96753, United States