https://youtu.be/hlT_QVYCKS4?t=2482 [eliteaccordion][elitetoggle title=“Generated closed captioned text”]What happens with the water when you’ve used it where does it all go you just push the lever and it’s gone it’s how does it all work can anything go down there are there even any rules and is the sink any different the bathroom sink the kitchen sink actually there is no difference sink toilets same thing behind these walls and under these floors all the drains meet up in a single pipe and head toward the sewers and going about our everyday lives we use a lot of water for drinking washing cooking going to the toilet and much more by using this water it becomes polluted the wastewater we produce is known as sewage everything that leaves the house through the main drain pipe meets up with the sewer right down here in some places to combine sewer both wastewater and storm water in other words everything from inside your house and everything from outside your house brain whatever goes into a single combined sewer offices shops factories and other industries together with rain water that runs off roofs and roads sewage is washed flushed or drained into sewers the underground network of sewers that collect all this wastewater and transports it to the sewage works is known as the sewerage system in the area it drains is the catchment area all of it heads towards the wastewater treatment plant in some places the sewers are separated one for wastewater and the other for storm water in that case only the wastewater heads towards the wastewater treatment plant the storm sewer goes straight to the river untreated because it’s only water right actually no it isn’t all the chemicals that you put on your lawn or the soap with all the phosphates that you wash your car with all head out the storm sewer if you’ve got a separated system straight into the room all the wastewater fins up at moist water treatment plants originally established by the Royal Commission on sewage disposal 1898 1915 objectives of sewerage treatment had as follows to avoid pestilence and nuisance disease and odor the protection of potable water sources from pollution by sewerage discharge and to produce effluence which after dilution with with water a suitable for abstraction as sources of potable supply sewage is a complex mixture of suspended and dissolved materials both categories constitute organic pollution the strength of sewage and the quality of sewage effluent are described in terms of their suspended solids and biochemical oxygen demand these two measures were originally either proposal devised by the Royal Commission the suspended solids are determined by way after the filtration of a known volume of sample through a standard glass fiber filter paper the results being expressed in milligrams per liter dissolved pollutants are determined by the biochemical oxygen demand they exert when incubated for five days at twenty degrees Celsius samples require appropriate dilution with oxygen saturated water and suitable replication the oxygen consumed is determined and the results are get expressed in milligrams per litre the two standards for sewage effluent quality proposed by the Royal Commission or for no more than 30 milligrams per liter of suspended solids and 20 milligrams per litre for biochemical oxygen demand the so-called 30 to 20 standard the Royal Commission in visits that the effluent of this standard would be diluted 8 to 1 with clean river water having biochemical oxygen demand of 2 milligrams per litre or less this standard was considered to be the normal minimum requirement and was not enforced by statute because the character and use of rivers varied so greatly currently most sewage treatment works are required to meet discharge standards set by the urban waste water treatment directive the flow of sanitary sewage alone in the absence of storms in dry season is known as dry weather flow DWF the purpose of these plans is to remove all solids and pathogens you know microorganisms like bacteria and stuff from the wastewater so when it gets reintroduced to the river it’s cleaner than when it arrived at the wastewater treatment plant when it arrives coarse screens remove large solids rags and debris from wastewater and are immediately disposed of it’s here that you see some of the most ridiculous things people have put down their toilets drains and sewers at least this stuff made it this far some things that the water can’t dissolve end up stuck in the sewers leading to sewers being clogged and homes being flooded after those fine screens are used to remove the smaller material in the same way next up is grit removal grit includes sand gravel and other heavy solid materials that are heavier than the organic solids in the wastewater removal of grit happens by getting the wastewater to flow in a spiral pattern heavier particles settle at the bottom of the tank while lighter organic particles are suspended and eventually carried out of the tank from there that water is sent into a settling basin this is where suspended solids settle out and floating scum is removed by skimmers scrapers in the tank moved continuously along the bottom to deposit the raw sludge into hoppers which is sent to a nearby plant where it’s made into pellets for fertilizer after the settling basins the wastewater is sent to the next step by a Archimedes screw pump which forces the liquid upwards the revolutions raise the water thread by thread until it comes out at the top of the cylinder there it is met by the fine curve screen where small items that have made it through the initial screening process are removed things like fruit and vegetable stickers they don’t dissolve and they clog up the system so when you’re pilling them off throw them in the garbage not down the sink now it’s time to get the stuff you can’t see some of this work is done by biological aerated filters essentially what happens here is that good microorganisms attached to porous rock eat up the bad microorganisms the waste water is pumped up through the rocks and the bacteria in the water sticks to the rocks bubbles are pumped in to keep the good bacteria alive and working the clean water goes up in the rocks with the bad bacteria attached to them go back down this cleansed water then flows into a channel on its way to be treated by ultraviolet light the water passes high output UV lamps where light disrupts the molecular structure of DNA molecules and the micro organisms this renders the cells unable to replicate before they die the disinfection stage takes seconds eliminates the need for chlorine and makes the final process much safer let’s look now at the sewage treatment process a sewage works such as this treats nearly 40,000 cubic meters of mainly domestic sewage each day at this site trade waste from two local food manufacturers comprises about 8% of the total flow rainwater runoff referred to a surface flow is also treated for simplicity we will refer to all the incoming waste waters as sewage that the sewage treatment works the incoming waste passes through screens which remove large pieces of debris such as plastic paper and cloth the liquid then flows through a number of channels which take out any grit washed in from roads the raw sewage entering the works passes through six millimeter mesh screens the collected solid matter is called screenings and typically comprises rags cotton buds sanitary products and paper the screenings are compacted and sent to landfill the sewage then flows to a grit extractor of the cross-flow type we Road grit and other inorganic matter settle out this material is subsequently washed and also sent to landfill the sewage is then passed forward to large tanks here fine particles sink to the bottom and form a sludge which is regularly removed and further treated on leaving the grit extractor the sewage enters the primary settlement tanks here approximately 70% of the remaining solid matter settles out and forms primary sludge which collects in a sump at the bottom of the tank periodically the sludge is pumped away for disposal or for treatment above this sludge lies the waste water it now has a greatly reduced amount of suspended solids and with it about 30% less biochemical oxygen demand or VOD for short here we use bacteria to clean up the liquid sewage the bacteria help purify the liquid by actively feeding on it and turning most of it into carbon dioxide water and nitrogen in biological filters we encourage bacteria to grow in deep beds of irregularly shaped stones gaps between the stones circulate air which lets the bacteria breathe and thrive that the liquid passes through them an alternative to biological filters is a process called activated sludge where air is bubbled through the sewage to encourage bacteriological growth the air can then be pumped or entrained from the surface by rotating paddles either way once the bacteria have done their work the liquid goes into further settling tanks to remove the remaining particles leaving clean water to flow to the river or if necessary onward to further treatment on this site the wastewater is treated in one of three different types of biological system namely biological filters activated sludge units or oxygen ditches first there were only the biological filters but over the years the activated sludge unit and oxygen ditches were installed here you can see the rectangular biological filters in many works they’re circular but irrespective of their shape biological filters are robust and easy to operate microorganisms growing on the clinker in the bed break down the organic matter in the effluent on leaving the filters the effluent is dosed with ferric sulfate in order to precipitate out the phosphates this prevents eutrophication occurring in the river when the treated effluent is finally discharged at the end of the process the effluent then goes to a humours tank for secondary settlement where microbial solids and precipitated phosphates settle out and are removed a sludge you can see that the water looks much cleaner than it was at the inlet an alternative to the biological filter is the activated sludge unit here the wastewater is aerated and mixed by fine bubbles of air blown through hundreds of ceramic or plastic diffusers such as this the organic matter in the sewage is again broken down by microorganisms but this time they’re suspended in the mixed liquor in a tank the remaining system is the oxygen ditch where almost one-fifth of the sewage at this plant is treated interestingly the oxygen ditch doesn’t require primary settlement the sewage is aerated with the help of large brush raters and the effluent moves around the ditch allowing the organic matter to be degraded by microbes in suspension on exiting it goes to a settlement tank and then to the gravel filter treated effluent from all three systems comes together before discharge into the nearby river you simplistic terms nitrogen in various forms is flushed rinsed or otherwise introduced into the sewer system almost all of this organic nitrogen urea for example is immediately hydrolyzed into ammonia in water gaseous ammonia nh3 is almost entirely converted to ionized ammonia or ammonium nh4 plus specialized autotrophic bacteria or nitrifiers convert the ammonium to nitrite no.

https://www.youtube.com/watch?v=7C1o6kZlYCw GLASCO ULTRAVIOLET Published on May 15, 2014 This video is about changing UV wastewater lamps in a horizontal configuration. The plant maintains 100 modules each with 6 lamps. The video is generic and meant to show engineers, owners and operators the maintenance involved. Entire lamp change would be 40 hours x 2 operators. note that some systems come with self cleaning rings which are moved along the glass surface to keep optical transmission high.

https://www.youtube.com/watch?v=R9R9jYUvgSI Secondary treatment consists of removing the major part of the dissolved pollution, mainly BOD5 and ammonia.