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Statistical evaluation of the effect of secondary municipal wastewater and solid waste leachate on ground water quality at Lawspet in Puducherry, India

Nathan N. S., Saravanane R., Sundararajan T.

Environment Protection Engineering

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2018

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Vol. 44, nr 1

85--102

EN

At Lawspet area in Puducherry, India, a unique situation of co-disposal of solid waste dumping and secondary wastewater disposal on land, prevails simultaneously within the same campus. So an attempt is made to assess the combined effect of this co-disposal on the environmental quality and pollution effects on groundwater quality with a view to correctly monitor the situation. Multivariate statistical analysis like hierarchical cluster analysis (HCA) and discriminant analysis (DA) were employed. HCA was performed on borewells, physiochemical parameters and seasons. Borewell clustering identified four clusters illustrating varying degree of groundwater contamination. In parameter clustering, two major clusters were formed indicating hardness and anthropogenic components. Temporal clustering identified three major clusters indicating pre-monsoon, monsoon and post-monsoon. Discriminant analysis revealed nine significant parameters which discriminate four clusters qualitatively affording 86% correct assignation to discriminate among the clusters. Also three major components viz. anthropogenic, hardness and geogenic responsible for groundwater quality in the study area were identified. Conclusively the investigation revealed that the direction of the contaminant transport is towards the southeast direction of the study area, where all the borewells (100%) are affected.

2

Modelowanie matematyczne przelewu burzowego z cylindrycznym regulatorem wirowym odpływu

Kaźmierczak B.

Rocznik Ochrona Środowiska

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2013

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Tom 15, cz. 3

2158--2174

EN

A simulation of the functioning of a modern overfall with a cylindrical vortex regulator on a combined sewage system was conducted in this work. In a cylindrical vortex regulator, liquid flows into the device through a connector tangent to the cylinder generator. From this, the liquid receives a vortex motion, which is maintained throughout the entire chamber width all the way to an outlet hole on the cylinder head. In the motion, peripheral speed is increased when approaching the cylinder axis. Because of the centrifugal force in the vortex chamber, the pressure decreases towards its axis until it reaches an ambient pressure on the air core surface. The air core being generated has a crucial influence on the throttling efficiency of the device. The atomized liquid in the outflow creates a cone with the angle of flare γ. For the modelling of storm overflow activity a combined drainage area of F = 60 ha was suggested. The overfall was loaded with sewage and wastewater. A typical, triangular hydrograph of the wastewater inflow to the storm overflow was applied here. The given hydraulic model of storm overflow activity includes a series of characteristic, occurring in sequence phases of filling and emptying of the overfall chamber. The phases were distinguished with the description of boundary conditions in reference to the precisely determined range of variables during the fillings and flows. On the basis of the formulated hydraulic and mathematical models of the storm overflow activity, a computer programme for the numerical simulation of the functioning of the aforementioned overflows was developed. The simulation of a storm overflow functioning on a combined sewage system proved a high level of sewage-treatment plant protection from a hydraulic overload by the application of modern, unconventional storm overflows. Irrespective of the assigned load, sewage outflow stream towards the sewage-treatment plant is stabilized on a demanded level. Current methods of designing storm overflows do not take into account the frequency of storm discharges to the receiver, as well as they do not offer the possibility of their duration and volume determination and thus they do not allow for the assessment of pollution load that is drained off in discharges towards receivers. The simulations of storm overflows functioning allow for determination of these parameters for already designed overflow and for any assigned load. Therefore they constitute a valuable instrument supporting the process of designing this type of objects, as it has been proved in this work.

3

Zmiany udziału frakcji ChZT podczas oczyszczania ścieków komunalnych z dużym udziałem ścieków mleczarskich

Struk-Sokołowska J.

Rocznik Ochrona Środowiska

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2011

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Tom 13

2015-2032

PL

Północno-wschodnia Polska jest regionem z największym pogłowiem krów mlecznych. Problem powstających tam ścieków mleczarskich i ich oczyszczania nadal nie jest do końca rozwiązany. Dlatego celowym wydało się podjęcie badań nad intensyfikacją procesu oczyszczania ścieków komunalnych z dużym udziałem ścieków mleczarskich. W tym celu określono zmiany frakcji ChZT w ściekach surowych oraz po kolejnych etapach mechaniczno-biologicznego oczyszczania ścieków komunalnych z dużym udziałem ścieków z przemysłu mleczarskiego.

EN

Development of our civilization has caused that urban centres have been deprived of natural retention system especially referring to rainwater. Present sewage systems, in most cases is not able to carry away a great intensity of sewage flow. Therefore, different technical interventions are undertaken in order to catch and keep this surplus of flow temporarily. Sewage transfer to receivers problem is solved in different way in each country. There are well-known solutions of either stationary or moving sewage pumping stations. However, most often outflow of excessive rainwater is performed gravitationally through outflow collectors linking storm overflows with water receiver. The outlet of these outflow collectors is usually equipped with shut-off check valve in order to protect terrains against flooding. However, practically these valves are not always used, whereas they are installed, are usu-ally deprived of proper care and preservation. Thus, their technical state make impossible for these valves to work. A research on practical ways of transfer sewage from the protected drain-age area to the receiver during the periods of high fillings has not brought a uni-versal and unfailing solution, which could have a wide application in practice. So the problem of working out a solution of hydraulic way of carrying away the rainwater to the receiver assure their natural, gravitational outflow during the periods of either low states and medium fillings in the receiver or during the period of high fillings their strained transfer. This kind of solution of transfer of rainwater to the water receiver are transfer reservoirs. A common solving feature of these reservoirs is that they are located on the side of drained terrain. This solution guarantees possible damage repairs even when in the receiver - river high states of filling appears. Transfer reservoirs can be applied in the following cases: (a) in separate sewage system on the outlets of the main collectors of the rainfall system, (b) in combined sewage system on the outlets of a storm canal, (c) in combined sewage system on the outlets of storm canals with simultaneous pumping of domestic and industrial wastewater to a wastewater treatment plant, (d) in case of collectors carrying away treated sewage from the wastewater treatment plant. In the paper transfer reservoir GEMINUS is presented. Transfer of sew-age, using this kind of reservoir, is done through applying system of air-compressors and proper combination of pressure systems.

4

Chlorki jako wskaźnik przemieszczania się zanieczyszczeń z lagun osadowych ścieków komunalnych w Zbąszynku

Gontaszewska A., Kraiński A.

Zeszyty Naukowe. Górnictwo / Politechnika Śląska

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2003

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z. 256

71-78

PL

W artykule przedstawiono wpływ ścieków gromadzonych w lagunach osadowych aa jakość wód podziemnych. Dla rejonu lagun stwierdzono zanieczyszczenie wód gruntowych m.in. jonami Cl, najwyższe w otoczeniu samych lagun. Przeanalizowano wielkość skażenia na całym terenie objętym monitoringiem. Na wykresach przedstawiono skład wody podziemnej w trakcie obserwacji. 16-letnie obserwacje sieci monitoringu nie rozwiązują kompleksowo problemu zanieczyszczeń i tła hydrogeochemicznego, ponieważ laguny osadowe istnieją już ponad 70 lat. Zauważalny jest związek z zagospodarowaniem terenu (las, uprawy rolne, zabudowa wiejska), co pozwala wskazywać także lokalne źródła . zanieczyszczeń, nie związane z lagunami osadowymi.

EN

In paper was described influence of sludge accumulated in a settling tanks on groundwater's quality. Chlorides pollution (highest in settling tanks neighborhood) was discovered. Volume of pollution in monitoring's area was analyzed. Groundwater's constitution during observation's period was shown in some graphs. 16-years-long observations period doesn't solve pollution and hydrogeohemical background problems because settling tanks have been existing for more than 70 years. There also exists a connection between groundwater pollution and land development.

5

High resolution 3D-ecosystem model for the Neva Bay and Estuary - model validation and future scenarios

Korpinen P., Kiirikki M., Rantanen P., Inkala A., Sarkkula J.

Oceanologia

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2003

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No. 45 (1)

67-80

EN

We have used a simple 3D-ecosystem model to describe nutrient dynamics and biomass production in the Neva Bay off St. Petersburg. The River Neva is responsible for carrying the waste waters of St. Petersburg to the Gulf of Finland. Literature values of chlorophyll-a concentrations and satellite images have been used for model validation. The results indicate that our model can reproduce both the temporal and spatial variation in the phytoplankton biomass with reasonable accuracy. The model was used to analyse scenarios describing the ecological effects of planned water protection measures. More efficient phosphorus purification was found to be the most effective measure for improving the water quality off St. Petersburg.