How Wastewater Treatment In SimpleWastewater treatment is intended to protect the environment against pollution of the waste water . Scientifically actual carrying capacity of the environment have a big enough to interference arising from the waste water pollution . However, the nature has limited ability in carrying capacity so that the waste water should be treated before disposal .Some simple ways of processing waste water , among others :1 Dilution ( Dilution )Wastewater diluted to a concentration low enough then just dumped into water bodies . But with the rising population , which means the increasing human activity then the amount of wastewater that must be disposed of too much water dilution and required too much anyway so this way can not be maintained anymore .Besides, this way cause other losses , including the danger of contamination of water bodies still exist , which eventually lead to the deposition of the siltation of water bodies , such as sewers , rivers , dananu , and so on . Furthermore, it can cause flooding .2 Swimming Oxidation ( Oxidation Ponds )In principle this method of wastewater treatment is the use of sunlight , algae ( algae ) , bacteria and oxygen in the natural cleansing process . Wastewater flowed into the large rectangular pool with a depth of between 1-2 meters . The walls and bottom of the pool does not need to be any layer . The location should be away from the pool and the residential areas in an open area so as to allow good air circulation .How it works as follows :The four elements that play a role in this natural cleaning process is sunlight , algae , bacteria , and oxygen . Algae with a grain khlorophylnya in wastewater perform photosynthesis with the help of sunlight so that thrive .In the synthesis process for the formation of carbohydrates from H2O and CO2 by chlorophyll under the influence of sunlight to form O2 ( oxygen ) . Then the oxygen used by aerobic bacteria to perform the decomposition of organic substances contained in waste water .Besides precipitation occurs . As a result the value of BOD of the waste water will be reduced so that would be relatively safe when thrown into water bodies ( time , lakes , and so on ) .3 IrrigationWastewater into open ditches were dug and the water will seep into the ground through the base and walls of the trenches . In certain circumstances the waste water can be used for irrigation of agricultural fields or plantations and also functions to fertilization but before the waste water should be drained through the wastewater treatment process first.This can be done especially for waste water from households , cow dairies , slaughterhouses , and others where the content of organic matter and a high enough protein needed by the plants .Wastewater treatment is an attempt to treat wastewater generated from various production processes before being discarded or reused . This process is intended to eliminate harmful substances or toxic substances contained in the liquid waste , so that when the waste is disposed of or reused , do not endanger the life of living beings .The techniques of wastewater treatment developed at this time are generally divided into three processing methods :1 . Processing physics2 . Processing chemical3 . Biological treatmentFor a certain type of wastewater , the three processing methods can be applied individually or in combination .Processing In PhysicsWastewater treatment in physics in general , carried out prior to further processing of the waste water . This is done so that the suspended particles are large and easy to settle or floating particles aside first.Screening ( screening ) is an efficient and inexpensive way to set aside large suspended particles . Suspended particles that can be removed easily settles easily with the deposition process . The main parameters for the design process is the deposition velocity of particles precipitate and hydraulic detention time in the sedimentation basin .Flotation process is used to eliminate floating materials such as oils and fats that do not interfere with subsequent processing . Flotation can also be used as a way of allowance of suspended particles ( clarification ) or sludge concentration sludge ( sludge thickening ) to provide airflow to the top ( water flotation ) .Filtration process in wastewater treatment , usually done to forestall the process of adsorption or the reverse osmosis process , will be implemented to eliminate as much as possible from the suspended particles in the water so as not to interfere with the process of adsorption or clog the membranes used in the process of osmosis .Adsorption process , usually with activated carbon , made to set aside aromatic compounds ( eg, phenols ) and other dissolved organic compounds , using activated carbon . This process is done especially if the results of this wastewater treatment , desired to be reused .Membrane technologies ( reverse osmosis ) is usually applied to small processing units , especially if the treatment is intended to reuse the treated water . It's just the cost of installation and operation is very expensive .
In Chemical ProcessingChemical waste water treatment is usually performed to remove particles that are not easily settled ( colloidal ) , heavy metals , phosphorus compounds , and toxic organic substances ; by applying certain chemicals are required .Allowance particles are in principle take place through changes in the nature of these particles , which can not be precipitated from be easily deposited ( flocculation - coagulation ) , either with or without the oxidation-reduction reaction , and also takes place as a result of the oxidation reaction .Deposition of suspended material insoluble by putting electrolyte having opposite charge to the charge koloidnya , so that the colloid charge neutralization occurs , so that eventually precipitated .Provision for heavy metals and phosphorus compounds by putting alkaline solution ( eg lime water ) , thus forming a hydroxide precipitate the metals or hydroxyapatite deposition . Deposition of the metal will be more stable if the water pH > 10.5 and to hydroxyapatite at pH > 9.5 . Specifically for hexavalent chromium , chromium hydroxide before it is deposited as [ Cr ( OH ) 3 ] , first reduced to trivalent chromium by affixing a reductant ( FeSO4 , SO2 , or Na2S2O5 ) .Provision for toxic organic substances such as phenol and cyanide at low concentrations can be mengoksidasinya with chlorine ( Cl 2 ) , calcium permanganate , aeration , ozone hydrogen peroxide .Basically we can obtain high efficiency with chemical processing , but the processing cost becomes expensive because it requires chemicals .Biological treatmentAll biodegradable liquid waste can be biologically treated . As a secondary treatment , biological treatment is seen as the most inexpensive processing and efficient . Within a few decades has developed various methods of biological treatment with any modifications .Basically , biological treatment reactors can be divided into two types , namely :1 . Suspended growth reactor (suspended growth reactor ) ;2 . Attached growth reactor ( attached growth reactor ) .In the suspended growth reactor , the microorganisms grow and thrive in a suspended state . Activated sludge process is widely known , takes place in this type of reactor . Activated sludge process continues to evolve with various modifications , such as: oxidation ditch and contact - stabilization . Compared with the conventional activated sludge process , oxidation ditch has several advantages , namely BOD removal efficiency can reach 85 % -90 % ( compared to 80 % -85 % ) and produced less sludge . In addition to higher efficiency ( 90 % -95 % ) , contact stabilization has other advantages , namely the total hydraulic detention time is shorter ( 4-6 hours ) . Contact - stabilization process can also be set aside BOD suspended through the absorption process in the contact tank so that no provision BOD suspended the preliminary processing .Oxidation pond and lagoon , either aerated or not , are also included in the suspended growth reactor types . For tropical climates such as Indonesia , hydraulic detention time for 12-18 days in the oxidation pond and in the non- aerated lagoon , enough to achieve effluent quality can meet the standards set . In the aerated lagoon with enough detention time of 3-5 days.In the attached growth reactor , the microorganisms grow on the media support by forming a film layer to attach himself . Various modifications have been developed over the years, among others :1 . Trickling filter2 . Disc biology3 . Filter submerged4 . Reactor fludisasiThe entire modification can produce BOD removal efficiency of approximately 80 % -90 % .In terms of the environment in which the ongoing process of biological decomposition , this process can be divided into two types :1 . Aerobic process , which takes place in the presence of oxygen ;2 . Anaerobic process , which takes place in the absence of oxygen .If BOD waste water does not exceed 400 mg / l , the process can be considered aerobic still more economical than anaerobic . At higher BOD of 4000 mg / l , anaerobic processes become more economical .In current practice , wastewater treatment technology , is no longer as simple as in the above description . However , in principle , all waste generated must go through several processing steps before being discharged into the environment or re- utilized in the production process , in which the above description can be used as a reference .Sources of Organic Liquid WasteWastewater originating from human activities (human sources ) and the activity of nature (natural sources) .Ø Human activity ( Human Sources )Several types of human activities that produce wastewater is activity in the field of household , office , commercial , industrial , and services . Activity in the industrial sector is also highly variable . Variations in the field of industrial activities influenced by the type of raw material processed / processed , the type of material so produced , production capacity , engineering / applied type of production process , and sebagainya.Berikut some kind of industry that produces liquid waste .No. . Types of Industrial Waste Water Component1 . Industry Ø Water Ethanol former leaching tanks and other equipment
Fermentation waste residue
Fusel oil , a fraction of the distillation column .2 . Industry Rubber Ø Water from the rest of the processing
Little latex does not clot
Serum containing organic and inorganic materials .3 . Industry Ø Palm Oil Wastewater from activities sterilization , purification , and hydrocyclone
Washing water from oil exploitation activities , seed or fiber separation , and washing the meat .4 . The Pulp and Paper Water Ø pulp washing after cooking and mechanical separation
Water from the conventional chlorine bleaching process and the removal of lignin in chemical pulping .5 . Industry Sugar Ø barometric condenser cooling water and
Water from the washing process on the removal of color , filter cake washing , and washing apparatus .6 . Nitrogen Fertilizer Industry Ø condensate containing ammonia , organic nitrogen , urea , and methanol .
Effluent from the water treatment system , demineralization , water boiler , and cooling water , absorber , and material storage tank .7 . Textile Industry Wastewater from the assessment process , the removal of starch , bleaching , dyeing , printing and process improvement .
Natural SourcesRain is a natural activity that produces liquid waste called run-off . Rain water that flows over the land surface will be the surface water can enter the channel domestic wastewater , as the flood water .Composition and Characteristics of Liquid Organic Waste
The composition of organic wastewaterIn accordance with the source of liquid waste has a very varied composition of each place and process . However , an outline of the substances contained in the liquid waste can be classified as in the following scheme :WastewaterWater Solidsorganic Inorganic- Protein - granules- Carbohydrates - The salts- Fat - The metals- Ammonia- Nitrite and nitrate compounds- And organic acidsWaste water originating from an industry is determined by the types of the industry itself . To determine levels and substances contained in waste water , so there are some parameters that need attention from every type of industry .
Characteristics of Organic Liquid WasteKnown characteristics of wastewater effluent quality parameters of various proficiency level . Wastewater quality parameters is important to know is :Suspended Solids 1.BahanSuspended solid material is a solid material that can be removed in the filtration ( filtration ) through standard media smooth with a diameter of 1 micron . Suspended solid bodies are grouped again into a solid material that is fixed (fixed solids ) and evaporating ( volatile solids ) . The solid material is vaporized organic material is expected to be eliminated through biological decomposition or combustion . The solid material remains a solid material that are permanent . Suspended solid material can also be grouped into a solid material that can be deposited ( settleable solids ) and a solid material that can not be deposited ( nonsettleable solids ) normally .Dissolved Solids 2.BahanThe solid material is dissolved solids contained in the filtrate obtained after removal of suspended solids . This material represents salts in solution , including mineral salts from the water supply section . The solid material dissolved is important especially if the liquid waste will be reused after processing . Dissolved solid material can not be removed by conventional treatment .3.BOD ( Biochemical Oxygen Demand )BOD ( Biochemical Oxygen Demand ) is a measure of organic matter content in the wastewater . BOD is determined by measuring the amount of oxygen absorbed by the sample liquid waste due to microorganisms during satuperiode of time, usually five days , at a certain temperature , generally 200 C. The BOD is a measure of the strength of a sewage main . BOD is also an indication of the effect that is expected to occur in the receiving water bodies associated with reduced oxygen content . As general , derjat processing achieved by building sipilih processing must be such that the BOD efluent will not degrade the oxygen content up to a certain level in the receiving water bodies so that water bodies can still function according to its designation .4.COD ( Chemical Oxygen Demand )Chemical Oxygen Demand ( COD ) is a measure of the oxidation of the sample persyratan needs beada on certain conditions , determined by using a chemical oxidant . In a particular system there is a relationship with the BOD COD , but it varies from each other .5.TOC ( Total Organic Carbon )Nik Orga Total Carbon ( TOC ) measure all the ingredients are organic . TOC was measured by the conversion of organic carbon in the waste water oxidation , catalytic , at a temperature of 9000 C , into carbon dioxide .6.TOD ( Total Oxygen Demand )Total Oxygen Demand ( TOD ) of a material , defined as the amount of oxygen required for the combustion of all materials at a temperature of 9000 C using Platinum catalysts .7.pHeffluent pH is a measure of acidity ( acility ) or alkalinity ( alkilinity ) liquid waste . pH indicates whether or not the preliminary pengolakhan ( pretreatment ) to prevent interference with the process of conventional wastewater treatment . In general it can be said that domestic wastewater pH is near neutral .8.DO ( Dissolved Oxygen )Dissolved Oxygen ( DO ) is important in the operation of the sewer system and wastewater treatment plant . The degree of oxygen content in wastewater is highly variable and not stable at all . The purpose of pre- treated wastewater management is to maintain sufficient oxygen content terlatut and to prevent anaerobic conditions . In the treated effluent , the degree of oxygen kandunagan 1 or 2 mg per liter can be achieved .Nitrogen 9.KandunganNitrogen in the waste material can be arriving in the forms of ammonia nitrate reduced to oxidized compounds . Tinng concentration of various forms of nitrogen toxic to specific fauna and flora . The most common form of nitrogen found in wastewater is ammonia , protein , nitrite , and nitrate . These pollutants can be measured by the total Kjeldahl nitrogen method .4 . Mechanism of Organic Liquid Waste Pengurain In AerobicWastewater treatment process is microbiological aerobic utilization of aerobic microbial activity in aerobic conditions to decompose organic substances contained in waste water into stable inorganic substance and does not provide the impact of pollution on the environment . Aerobic microbes is already present in nature in an unlimited number and always be obtained very easily . In a limited capacity , nature itself has been capable of neutralizing organic substances contained in waste . However , in the vast quantities of waste produced as a byproduct of many industrial , sewage treatment efforts need to be held to preserve nature in addition to getting a new product that has economic value .Aerobic microbes that play a role in the aerobic microbiological process include:1 . BacteriaIn water and wastewater treatment is important because bacteria bacterial culture can be used to remove organic materials and minerals from the unwanted waste water . Most bacteria are kemoheterotrofik that use organic materials as a source of energy and carbon . Some species oxidize reduced inorganic compounds such as NH for energy and use CO2 as a carbon source . Bacteria kemoheterotrofik is important bacteria in wastewater treatment because the bacteria will break down the organic material , oxidizing ammonia nitrogen to nitrate nitrogen mainly by nitrifying bacteria .Reactive part of the bacterial cell is the cytoplasmic membrane . All inorganic or organic material that must be metabolized by the cells through the membrane . The mechanism of transport of most of the molecules through the membrane allegedly caused by reactions with specific enzyme system called permease . The molecules that do not have a permease system can not enter cells and therefore is not metabolized . This explains that the bacteria use selective nutrients and necessary reason why mixed cultures in wastewater treatment .The types of bacteria that play an important role in the decomposition of organic waste in aerobic include: Zooglea ramigera , Escherichia coli , Alcaligenes sp , Bacillus sp , Corynebacterium sp , Nocardia sp .2 . Fungus / MushroomFungi are microorganisms nonfotosintetik , multi -celled , aerobic , branching , filamentous metabolize food that is not dissolved . The composition of fungi cells can be expressed empirically by C ¬ 10H17O6N . Mold is not active in the anaerobic process . Because fungi cells contain less nitrogen than no cell bacteria, mold will compete better in the waste that has low levels of nitrogen than is needed for the synthesis of bacteria . The nature of the filaments of the fungus makes less desirable organisms in biological wastewater treatment unit because it does not settle well .3 . ProtozoaProtozoa are found in the aerobic treatment system including flagellates , ciliate and ciliate -free moving rod bound to the solid particles . Protozoa are important in waste management because these organisms will feed on bacteria so that the number of bacterial cells that is not excessive . In addition , protozoa will reduce organic materials that are not metabolized in the handling system and helps produce effluent with higher quality and clearer .Activated sludge unit that is free of protozoa produce more turbid effluent . Turbidity is caused by the presence of a large number of bacteria are dispersed . As hasilnaya , BOD and solids sedimented from the high effluent . The addition of ciliate protozoa will improve effluent quality and reduce the amount of bacteria .4 . AlgaeThe composition of the algae cells can be expressed with C106H180O45N16P . In the decomposition process of microbiological waste , algae symbiosis with bacteria , which the algae obtain energy from sunlight and use inorganic materials are described as follows :CO2 + H2O + NO3 + PO4 + O2 + light energy C106H180O45N16POxygen is released into the environment and are used by bacteria during metabolism of organic materials .Wastewater Treatment In MicrobiologicalIn line with the development of human life and activity , it also raised a variety of types and amounts of waste material in a relatively very short time , before it aeorob organic compounds and anaerobically . Primarily to the presence of oxygen , aerobic microbial compounds will oxidize organic compounds to form new cells and forms a more stable besides produce CO2 , NH3 , and H2O , whereas anaerobic mikraoba in the absence of oxygen to oxidize organic compounds into new cells and compounds such final CH4 , CO2 , NH3 and others.Aerobic :The new cell Microbial Organic compounds + + O2, CO2 , NH3 , H2OWhile anaerobic :The new cellOrganic compounds Microbial Cells + Alcohol + new Asinogen methanogenic microbial CH4 , H2O , H2S , NH3 , CO2Microbiological reaction speed is controlled by the presence of enzymes as biological catalysts produced by microbes . The enzyme has a high specific , mengkatalisanya only specific reaction and is influenced by several environmental factors : temperature , pH , and so forth . Various enzymes are often encountered in microbiological processes include: hydrolase , reductase , oxidase , lipase , amylase , phosphatase and others.In the aerobic process in which oxygen is a factor that should be there . There are three types of aerobic processes , namely :1 . Tricking Filter ( Filters Drops )Tricking filter is one of the wastewater treatment applications using biofilm technology . Biological processes that occur in biofilms is a pseudo steady state , ie the neglect of reaction and diffusion biofilm growth substrate at a given time scaleSieve drops designed to handle aqueous liquid wastes . Sieve drops not filter but aerobic oxidation units that absorb and oxidize organic materials in waste through the filter media . Drops in the filter media is generally crushed rock or coral with a large size , generally 2 to 4 inches , or plastic media with various configurations .Facultative heterotrophic bacteria constitute the largest population of microorganisms in the filter drops Protozoa and other forms of animal life which are higher in the filter and algae will grow on the surface of the filter that cargo is not excessive , but it will not grow under the surface because sunlight can not penetrate . Organic matter in the waste water will stimulate biological growth on the media surface . The organic material will diuraiakan by microorganisms attached to the filter media . Organic material as a substrate dissolved in the liquid waste is absorbed biofilm ( a slimy layer ) . In the outer layers of the biofilm , the organic material described aerobic microorganisms . The growth of microorganisms will thicken the layer of biofilm . Diffused oxygen can be consumed before reaching the biofilm thickness maksimium . When reached full thickness , oxygen does not reach full penetration , so that the inside surface of the media or become anaerobic .At the time of the biofilm layer thickness has the addition of organic matter adsorbed can be decomposed by microorganisms , but tudak can reach the surface of microorganisms that are in the media . In other words , are not available organic matter to carbon cells on the surface of the media , so that the organisms on the surface will experience a phase of indegenous ( dead ) . In the end , the microorganisms as the biofilm will be separated from the liquid medium and the entrance will also removing biofilm and pushed out . After that , a layer of new biofilm will soon grow . Important to note that the growth of microbes are not killed by the toxic conditions in the waste because the filters will not work on efficiency that has been designed to prtumbuhan established back that can take a long time .2 . Activated Sludge ( Activated sludge )Activated sludge treatment system is processing by way of culturing bacteria in the aerobic tank aerase which aims to reduce the organic carbon or organic nitrogen . In a decrease in organic carbon , bacteria whose role is bekteri heterotrifik . Sources of energy derived from the oxidation of organic compounds and carbon sources of organic carbon bersal . BOD or COD is used as a measure or unit expressing the concentration of organic carbon which is hereinafter referred to as the substrate .Activated sludge process based on pengguanaan number of microbes present in the form flog suspended due to agitation , so that will be in contact with organic compounds in waste water in the frequency often . Agitation can be done by mechanical agitation with a turbine or by flowing air ( aeration ) .In the activated sludge process consists of two tanks namely , aeration tank where organic matter decomposition reaction occurs biochemically by microbes in a state of sufficient oxygen and biosolid tank where sludge is separated from the liquid .Waste water with activated sludge into the aeration tank , where aeration is done continuously to provide oxygen . In the aeration tank , the decomposition reaction of organic substances contained in waste water by microbes that are biochemically contained in activated sludge gas into CO2 and new cell . The number of microbes in the aeration tank will multiply the resulting new cells .Oxidation reactions and the synthesis of the cell that occur are as follows :Oxidation reactionNutrient CHONS + O2 + CO2 + NH3 + BACTERIA C5H7NO2biomassSynthesis / Respiration BACTERIAC5H7NO2 + 5O2 CO2 + 5 H2O + NH3 + Energy3 . Stabilitation Waste Ponds / Oxydation Ponds ( Swimming Stabilization / Oxidation )Oxidation pond -like pool shallow depth of 1-1.5 m , embankment structure with a large surface area to maintain aerobic conditions . In areas where land is relatively flat and the price is cheap , oxidation ponds would be more economical than other types of aerobic biological treatment . Effluent ( liquid waste ) generated quite stable . Barriers to the use of this system is the need of large tracts of land , the system tends to be anaerobic when excessive organic matter and temperature changes . The problem faced is the odor that arises due to the change of seasons from aerobic to aerobic conditions . To prevent this you can add an oxidant such as the addition of nitrate . Handling of waste with this system takes several weeks or months .In oxidation ponds are bacteria and algae ( algae ) which is a key microorganisms in an hetrotrofik oksidasi.Bakteri responsible for the stabilization of organic matter in organic waste kolam.Ketika metabolized by bacteria that produce a final product that can be used by algae . Because of the sun then a process of photosynthesis that produces oxygen . Bacteria are responsible for the processes of oxidation and reduction and algae play a role in the use of excess carbon dioxide to produce oxygen .Biological Process ( Microbiological ) Aerobic ElseAnother industry- waste treatment process which is done by mikrobiolgis aerobic nitrogen removal is the process ( Nitrification ) . Nitrification can be defined as the biological conversion of nitrogen from organic or inorganic components of the reduced form to form teroksidasi.Nitrifikasi is a reaction that is eksotermal.Pada water pollution treatment , nitrification is a biological process that will oxidize ammonium ions into nitrite or nitrate form .Nitrifying bacteria are known to the nitrification process is Nitrosomonas oxidize ammonia to nitrite and Nitrobacter into nitrate . In brief, the reaction changes are as follows :NH4 + + CO2 + O2 + Nitrosomonas Biomass NO2 - + H2O + H +Then proceed with the process nitratasi as follows:NO2 - + CO2 + O2 + NO Nitrobacter Biomass - + H +Other bacteria capable of oxidizing ammonia to nitrite among other bacteria of the genus Nitrosospira , Nitrosococcus , and Nitrocystis . While the bacteria are able to oxidize nitrite to nitrate in addition to the Nitrobacter , also of the genus Nitrocystis.Dan Nitrogleoea and many other microbes of the type of heterotrophic bacteria and fungi are also known as nitrifying organisms .Basically the factors having an effect on nitrification include retention time ( SRT ) , dissolved oxygen , temperature , pH , and concentrations of ammonia and nitrite .a) Retention TimeRetention time is the time associated with the generation of microbial amount of energy required for the oxidation process . The nitrification process depends on the aerobic microbial metabolism and microbial nitrification process has a long generation time which can be 10 hours or more depending on the environment that microbes were . The minimum retention time of treatment should be longer than the nitrification rate of microbial growth and also depends on the temperature and the concentration of inhibitor materials .b ) Dissolved OxygenThe availability of dissolved oxygen is needed to sustain life nitrifying bacteria . Microbial nitrification sensitivity to low levels of dissolved oxygen is one of the causes of these microbes are active and difficult to breed .c ) TemperatureNitrification can take place either at 30oC - 36oC . . Nitrification is carried out at the optimum temperature will cause the rate of microbial growth will be slow and result in an increase in retention time . In these conditions the nitrification process will continue despite the longer time .d ) pHIn general, microbial nitrification have optimum growth pH range of bases , ie, between 7.5 to 8.5 .e ) Concentration of Ammonia and Nitrite
