The self purification process of water bodies or processes involving biological, chemical and physical processes. Samples of water are taken at areas upstream and downstream from the sewage outlet. Oxygen sag curve transparent materials gases scribd. Pdf file or convert a pdf file to docx, jpg, or other file format. Describe the effects of flow and turbulence on the oxygen sag curve. This curve is an important tool for understanding how our blood carries and releases oxygen. The oxygen sag curve is shown during a cso discharge and at different times, t, after the event, i. Just like animals and humans living on land, animals that live in water need oxygen to survive. Oxygen sag curve benoit cushmanroisin by far the most important characteristic determining the quality of a river or stream is its dissolved oxygen, do measured in mgl. Explain the effect of temperature on oxygen sag, considering both physical and biological impacts. The presence of sewage reduces the oxygen content of the water and increases the. Read on to find out just how to combine multiple pdf files on macos and windows 10. The oxygen sag curve can describe the decrease in oxygen that occurs.
Only when the amount of oxygen is extremely low, as in. Ce6605 notes environmental engineering 2 regulation 20. The drop and rise in do levels downstream from a source of bod is called the do sag curve. The oxygenhemoglobin dissociation curve, also called the oxyhemoglobin dissociation curve or oxygen dissociation curve odc, is a curve that plots the proportion of hemoglobin in its saturated oxygen laden form on the vertical axis against the prevailing oxygen tension on the horizontal axis. Chp7 do sag curves streams sewage treatment water and. Problem illustrating the use of the streeterphelps equation. Oxygen transport basic equations and applications environmental hydraulics dissolved oxygen in water necessary for aerobic life in water. The streeterphelps equation determines the relation between the dissolved oxygen concentration and the biological oxygen demand over time and is a solution to the linear first order differential equation. To combine pdf files into a single pdf document is easier than it looks. The number of observa tions used for computing the averages are tabulated at. Dissolved oxygen downstream from a source of organic pollution. The pdf format allows you to create documents in countless applications and share them with others for viewing.
The general mathematical properties of point of pollution initial or reference point. Self purification of river water prof umesh t kulkarni. Curve a depicts an oxygen sag without anaerobic conditions. If your pdf reader is displaying an error instead of opening a pdf file, chances are that the file is c. Lafayette college department of civil and environmental. Water pollution control system operator certification. Model relates the rate of change of the oxygen deficit with distance to the spatial rates of oxygen. Mathematical approach to a lake system the governing equation used to estimate the dissolved oxygen concentration in stream water is derived by taking a mass balance of bod in the system, such. Air is dissolved at the water surface and then transported into the water mass by turbulence andor currents. Oxygen transport basic equations and applications dissolved. Once youve done it, youll be able to easily send the logos you create to clients, make them available for download, or attach them to emails in a fo. The oxygen sag and dissolved oxygen relationships in streams.
This contains 5 multiple choice questions for chemical engineering test. While the saturated value dos is rarely achieved, a stream can nonetheless be considered healthy as long as its dissolved oxygen do exceeds 5 mgl. This differential equation states that the total change in oxygen deficit d is equal to the difference between the two rates of deoxygenation and. On the other hand, the shape of myoglobins oxygen binding curve is hyperbolic, meaning that it holds onto oxygen much tighter. Oxygen sag curve solved examples waste water engineering. The paint program can help you make new image files, but it cannot open document or pdf file. Oxygen sag curve 5 questions mcq test has questions of chemical engineering preparation. Mar 24, 2018 standards for disposal methods dilution self purification of surface water bodies oxygen sag curve land disposal sludge characterization thickening sludge digestion biogas recovery sludge conditioning and dewatering disposal advances in sludge treatment and disposal.
Self purification of river water prof umesh t kulkarni 2. This test is rated positive by 90% students preparing for chemical engineering. How to shrink a pdf file that is too large techwalla. Obviously, the place of greatest environmental concern is the do minimum. Multiple point source curve a is the present predicted dry flow profile with observed river sampling results. The ultimate biochemical oxygen demand ubod is a parameter that quantifies the oxygen required for the total biochemical degradation of organic matter by aquatic microorganisms. On the do sag curve a minimum concentration occurs at some point, along a stream. The derivation of the do sag equation is the objective of this article.
Ubod and the rate of oxygen consumption are frequently used in mathematical models to predict the impact of an effluent on receiving bodies such as lakes and rivers. This is important, especially when sludge is accumulated along the bottom of a stream. Do sag curve q1, bod1 ss1 q2, bod2 ss2 residents industry saturation do cs travel time, days dissolved oxygen, mgl oxygen depletion initial deficit d 0 oxygen addition reaertaion critical deficit dc t c. Adobe designed the portable document format, or pdf, to be a document platform viewable on virtually any modern operating system. Stream must have a minimum of 2 mgl do to maintain higher life forms, while most game fish require 4 mgl. Describe the receiving stream oxygen sag curve downstream from a discharge point. Chp7 do sag curves streams free download as powerpoint presentation. Typical dissolved oxygen sag curve for a polluted stream. Oxygen deficit is represented mathematically by for constant equilibrium conditions, i. Purification capacity and oxygen sag in sringin river. Curve b is the expected dry flow do profile after implementation of pollution control measures ahmed and mohammed, 1988. Oxygen sag or the oxygen sag curve refers to the reduction in dissolved oxygen plotted over a distance along a water body from a point at which sewage or other pollutants have been discharged. The rate of deoxygenation depends upon the amount of organic matter remaining to be oxidized at a given time as well as on the temperature of reaction, hence at given temperature, the curve showing depletion of do with. Dissolved oxygen depletion dissolved oxygen sag curve mass balance approach originally developed by h.
By michelle rae uy 24 january 2020 knowing how to combine pdf files isnt reserved. The software package fate uses this model to study the do levels down. Water pollution control system operator certification commission. Reaeration coefficient as a function of depth and velocity. C dissolved oxygen concentration do cs dissolved oxygen concentration at saturation, predicted from henrys law. The deficit increases at the same rate that oxygen is used the dissolved oxygen deficit is the main driving force for reaeration oxygen deficit. Figure 1 shows the observed oxygen sag curve for average dos at 27 stations during streamflows of less than 7020 cfs measured at kingston mines. Introduction it is a natural process of rivers, lakes or canals to recover the rate of dissolved oxygen values of the highest concentration of oxygen which is one of the best indicators of water quality. The phenomenon of oxygen sag is usually related to the release of organic pollutants or nutrient elements, which promote the growth of oxygen consuming. Making a pdf file of a logo is surprisingly easy and is essential for most web designers. Recall that biochemical oxygen demand bod refers to amount of dissolved oxygen used by microorganisms to decompose the organic matter in the water. The minimum lies where ddodx 0, which is found to be at. Chp7 do sag curves streams sewage treatment water and the. Do sag curve q1, bod1 ss1 q2, bod2 ss2 residents industry saturation do cs travel time, days dissolved oxygen, mgl oxygen depletion initial deficit d 0 oxygen.
Mathematical approach to a lake system the governing equation used to estimate the dissolved oxygen concentration in stream water is derived by taking a mass balance of bod in the system, such that the change inflow of outflow of other losses. Chemical analysis allows us to determine the dissolved oxygen levels. When it comes to the cycles it goes over, why they are important. Label the point which represents the critical distance downriver. This article explains what pdfs are, how to open one, all the different ways. C dissolved oxygen concentration do cs dissolved oxygen concentration at saturation, predicted from henrys law kr reaeration rate constant. Searching for a specific type of document on the internet is sometimes like looking for a needle in a haystack. If your scanner saves files as pdf portbale document format files, the potential exists to merge the individual files into one doc. Oxygen sag curve mcq to study with solutions a complete question bank. Saturation dissolved oxygen can be read from table. Aalborg universitet pollution from urban runoff oxygen.
This mcq test is related to chemical engineering syllabus, prepared by chemical engineering teachers. The curve of figure 1 was defined in the work of streeter and phlps as where l bod remaining at any time, tppm. Zones of pollution pollution and selfpurification of stream and changes in the aquatic ecology by the disposal of sewageindustrial wastewater. C s does not change, the rate of change in the deficit. This initial decrease s due to bacterial action which uses dissolved oxygen.
Oxygen sag curve pogil the image above shows a sewage pipe and information about water quality downstream from the pipe. Pollution of streams o oxygen sag curve o factors influencing recovery fig. Flowing streams can recover from moderate levels of degradable water pollutants with the use of dilution and biodegredation if their flows are not flow reduced lakes. Label the coordinate of the critical distance downriver. These two concurrent processes of oxygen consumption and oxygen replenishment produce an oxygen sag curve, i. Flowing streams can recover from moderate levels of degradable water pollutants with the use of dilution and biodegredation if their flows. In a polluted stream, the do content goes on reducing due to decomposition of volatile organic matter. Oxygen sag curve for chemical engineering helps you for every chemical engineering entrance exam.
The self purification process of water bodies or processes involving biological, chemical and physical processes working simultaneously on biological pollutants, oxidizing them and increasing the amount of. The resulting oxygen sag curve has a minimum value of do, somewhere downstream, equal to 3. Purification capacity and oxygen sag in sringin river, semarang. Just below the discharge point, the do of the steam is equal to the saturation value of 10.
Oxygen demanding wastes can deplete the level of dissolved oxygen do in water. As the river reaerates due to atmospheric mixing and as algal photosynthesis adds oxygen to the water, the oxygen levels will slowly increase downstream. Luckily, there are lots of free and paid tools that can compress a pdf file in just a few easy steps. Biochemical oxygen demand and the dissolved oxygen sag. Dilution of pollution in lakes is less effective than in streams because most lake water is not mixed. Note that this is the same form of equation we used in the gas transfer lab. Derivation of oxygen sag curve the solution to the dissolved oxygen and bod in the environment is a very simple linear algebra practice.
Sketch the oxygen sag curve, as it would have been only four day after the breakdown of the treatment plant. Sketch the new oxygen sag curve a long time after the breakdown. Effect of photosynthesis and respiration not considered. Determine the theoretical oxygen demand for 150 mgl of glucose. This is called the oxygen sag curve or the streeterphelps oxygen sag curve. Do sag curve, derivation of dissolved oxygen sag curve. Phelps model was developed to predict the dissolved oxygen concentration do in water located down. Algae add do during daytime hours while photosynthesis is occurring, but at night its respiration removes do. Biochemical oxygen demand bod concept measurement modeling nitrogenous bod do dynamics in river do sag curve modeling do in the river solution. Most electronic documents such as software manuals, hardware manuals and ebooks come in the pdf portable document format file format. One of the fun things about computers is playing with programs like paint. Now, substitute the rate expressions into the mass. Hence the model is referred to as the streeterphelps model. When water in creeks and rivers pours over rocks, oxygen.
If the streeterphelps equation is differentiated with respect to time, and set equal to zero, the time at which the minimum do occurs is expressed by. The resulting pattern in dissolved oxygen concentration versus distance downstream from a waste source is known as the dissolved oxygen sag curve. While the saturated value dos is rarely achieved, a stream can nonetheless be considered healthy as long as its dissolved oxygen. This value will be related to the characteristics of the stream. Oxygen from the atmosphere dissolves in river and lake water, and it is this oxygen that fish and other aquatic animals use to breathe. Oxygen sag oxygen sag model one of the earliest mathematical water quality models was developed by for the o hio river b y h. Biochemical oxygen demand and the dissolved oxygen sag curve. Request pdf the development of simple dissolved oxygen sag curve in lowland nontidal river by using matlab this paper was. Depending on the type of scanner you have, you might only be able to scan one page of a document at a time. Sketch the new oxygen sag curve starting just after the breakdown. Pdf is a hugely popular format for documents simply because it is independent of the hardware or application used to create that file. Sketch the oxygen sag curve, as it would have appeared four day after the breakdown of the treatment plant. Solubility of oxygen in water described by henrys law. What is the approximate dissolved oxygen concentration in a healthy natural water body.
A pdf file is a portable document format file, developed by adobe systems. You can use the tools in paint to add something to a different document. Limitations of oxygen sag equation effect of sediment oxygen demand sod not considered. An oversized pdf file can be hard to send through email and may not upload onto certain file managers.
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