Excess activated sludge withdrawal system and subsequent treatment and disposal of waste sludge. Contact stabilization activated sludge is characterized by the use of two aeration tanks for each process train, one to contact the influent wastewater and return activated sludge contact tank and the other to aerate the return activated sludge stabilization tank and promote the biodegradation of the organics absorbed to the bacterial flocs. Wastewater technology fact sheet oxidation ditches description an oxidation ditch is a modified activated sludge biological treatment process that utilizes long solids retention times srts to remove biodegradable organics. Activated sludge process control and troubleshooting chart. Learn for free, pay a small fee for exam and get a certificate. The activated sludge process is the most commonly applied biological wastewater treatment technology. The activated sludge process has the advantage of producing a high quality effluent for a reasonable operating and mainte nance costs. In this system, wastewater is added to a single batch reactor, treated to remove undesirable components, and. The flow diagram and general description is that given above in the activated sludge background section.
These videos are provided by nptel elearning initiative. Water and waste water engineering video lectures from. A reactor in which the microorganism responsible for treatment are kept in suspension and aerated 2. Browse through water and waste water engineering civil engineering video lectures by prof. In the activated sludge treatment process, the removal of suspended solids from wastewater is usually through gravity separation in a clarifier. Nptel, online courses and certification, learn for free. Certain environmental conditions are established that select. Activated sludge process contd click on the video link shown below to play the video on youtube. The sludge volume index svi is the volume of the sludge in ml for one gram of dry weight of suspended solids ss, measured after 30 minutes of settling. However, in a sbr which is again works on a similar principal, but in this the processes are operated in a batch mode. The activated sludge process uses microorganisms to feed on organic contaminants in wastewater, produc ing a highquality effluent. The conventional activated sludge process is used over a wide range of wastewater flow rates, from small to very large plants. Sludge bulking is a common problem in activated sludge processes krhutkova et al. The existing processes include preliminary treatment, primary settlement, a plug flow activated sludge plant asp and final settlement tanks.
So, that is what the conceptual process that takes place in activated sludge system. An activated sludge system is to be used for secondary treatment of 10,000 m 3 day of municipal wastewater. The aeration tank in a conventional activated sludge process is typically designed with a long, narrow. An activated sludge reactor with surface mechanical aeration oxygen supply at the stickney water reclamation plant in chicago complete mix aeration system for activated sludge process at the eastman kodak company manufacturing facility in rochester, ny. Suspended growth activated sludge treatment process configurations basic activated sludge process consists of the following 3 basic components.
The typical activated sludge process is actually a suspended growth system. Too few or too many organisms in a system will cause operational control problems, reducing treatment plant efficiency and causing an added load on the receiving waters. Activated sludge process contd video lecture water. Lecture 22 activated sludge process modifications duration. The activated sludge excess biomass or cell mass removed from the secondary treatment process. For the love of physics walter lewin may 16, 2011 duration. Deals with what is activated sludge, mechanisms and kinetics of treatment, design of activated sludge process, secondary clarifiers and their design and bulkin slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Activated sludge treatment process concept and system. Activated sludge wastewater treatment is widely used by many municipalities.
So, there has to be a aeration tank which is where the organic matter is stabilized or decomposed by the action of bacteria under aeration. Settled biomass activated microorganism function of activated sludge. Ohio environmental protection agency methodology page 2. Activated sludge wastewater treatment provides many advantages, but it may not be appropriate in all situations. Aeration systemoxygen requirements and oxygen transfer system.
Wastewater flows into a tank or series of tanks that contain a high concentration of microorganisms. Wastewater technology fact sheet sequencing batch reactors description the sequencing batch reactor sbr is a fillanddraw activated sludge system for wastewater treatment. In this process, a bacterial biomass suspension the activated sludge is responsible for the removal of pollutants. Finham sewage treatment works stw serves a population equivalent of 430,470 for coventry and its environs. The following is a set of lecture notes from the class, prepared by dr. This process utilizes a multichamber reactor unit that uses microorganisms as a method to remove nutrients from the water. Tricking filters and rotating biological contactors. A process to reduce the concentration of suspended matter in water. The activated sludge form the underflow of the final setting tanks should be returned to the inlet of the aeration tanks at a rote sufficient to maintain the mlss concentration at the design value. The concentration of the activated sludge solids and the condition of those biological solids determines the effectiveness of an activated sludge process. Activated sludge aerator in lansing, michigan source. Simultaneous evaluation of bioactivity and settleability. Bs murty department of civil engineering, iit madras. Activated sludge the activated sludge method, first instigated in 1914, involves developing a culture of bacteria and other organisms in a large tank and on lanes containing the settled sewage.
Design example of conventional activated sludge process. It is a condition in which, due the overabundance of filamentous organisms. To illustrate, if waste activated sludge, which is typically pumped from secondary tanks with a content of 0. Fm ratio and the operation of an activated sludge process. In the field of wastewater treatment, there comes a pivotal moment when most of us realize that. Ligy philip, does not currently have a detailed description and video lecture title. If you have watched this lecture and know what it is about, particularly what civil engineering topics are discussed, please help us by commenting on this video with your suggested description and title. Lecture 23 activated sludge processcontd nptel waste.
Disadvantages of activated sludge process not very flexible method if there is sudden increase in the volume of sewage or if there is sudden change in the character of sewage, there are adverse effects on the working of the process and consequently the effluent of bad quality is obtained. Introduction to the activated sludge process historical development a developed around 19 in manchester b it is a biological, secondary treatment activated sludge. The federal water pollution control act amendments of 1972 public law 92500 established the national goals to restore and maintain the chemical, physical and biological integrity of the nations waters. Activated sludge process the activated sludge process is an aerobic, continuousflow system containing a mass of activated microorganisms that are capable of stabilizing organic matter. Lecture notes water and wastewater treatment engineering. Lecture 21 biological unit processesactivated sludge process. Activated sludge design, startup, operation, monitoring.
Activated sludge process, design criteria engineering. Activated sludge process control and troubleshooting class a manual. Oxygen in the form of air or pure oxygen is forced into the sewage by mechanical means to sustain the oxidation process, more sludge is made. So, activated sludge process typically consists of two separate chambers, or two separate tanks we can call that. Design example of extended aeration activated sludge. Request pdf simultaneous evaluation of bioactivity and settleability of activated sludge using fractal dimension as an intermediate variable bioactivity and settleability of activated sludge. Design of activatedsludge process involves details of sizing and operation of the following main elements. Due to increase in sludge settling rate, the load as the secondary settling tanks can be raised up to 50 m 3 m 2 day and the size of the settling tanks is reduced. The quantity of the return sludge is determined on volumetric basis. The weight of microorganisms under aeration, from fm ratio and the operation of an activated sludge process gary lee mishoe gary lee mishoe, cao, is the utilities director for lake placid activated sludge process ranges for.
It is here that biological oxidation of dissolved and fine suspended organic matter takes place. Activated sludge process design calculation, example. Notes on activated sludge process control page ii total solids are defined as all the matter that remains as residue upon evaporation at 103 to 105 oc. Filamentous foaming and bulking in activated sludge. Iit nptel waste water engineering civil engineering online video lectures, courses, tutorials, books civil engineering bridges, autocad. Chapter 3 sludge thickening thickening is a procedure used to increase the solids content of sludge by removing a portion of the liquid fraction. Aerobic activated sludge process was only able for partial toc removal from a spww. Due to denseness the sludge settles at faster rate. Mukesh kumar jaga barkat khan amit verma sushil kumar meena. The biological oxidation takes place because aerobic microorganisms, organic matter and dissolved oxygen are all brought together in the aeration tank. This video lecture, part of the series water and wastewater engineering by prof.
Activated sludge design, startup, operation, monitoring and troubleshooting. Lecture 22 activated sludge process modifications youtube. Abstract primary or secondary sewage sludge in medium and large wwtp are most. It is intended to be used as an aid in the presentation of the mdeq activated sludge process control training course, along with numerous handouts, class discussion, and an abundance of slides. Finham stw activated sludge plant 2019 water projects. The process consists of delivering clarified wastewater, after primary settling, into an aeration basin. Total solids can be classified as either suspended solids or filterable solids by passing a known volume of liquid through a filter. This activated sludge training manual was prepared by the michigan department of environmental quality, operator training staff. How does activated sludge wastewater treatment work. Uvush 2 o 2 process at optimum condition was able to remove more than 90% toc in spww effects of various operational parameters on the uvush 2 o 2 process were studied combined uvush 2 o 2 and aerobic as resulted in higher mineralization while lower oxidant consumption. After primary clarification, the bod is 150 mgl, and it is desired to have not more than 5 mgl of soluble bod in the effluent. Types of activated sludge process sewage treatment. Combination of sonophotolysis and aerobic activated sludge. Water and waste water engineering civil engineering course from iit madras nptel lecture videos by prof.
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