Biogas Reactor    2: B Inlet City Neighbourhood Household IOGAS RE ACT OR Biogas Pipe Management Level:    Household Public Shared Slurr Biogas Seal Y

Home , Blackwater (coal)

S .12 80 Compendium of Sanitation Systems and Technologies Functional Group S: Collection and Storage/Treatment ume of the reactor is constant. As gas is generated it generated is gas As constant. is reactor the of ume vol- the dome, fixed the In digesters. dome floating or dome fixed as built be can They generated. waste of soil characteristics, available resources and the volume space, on depending tanks, ground, below or above installed prefabricated or domes brick-constructed be can reactors Biogas Design Considerations inactivated. andpathogensodourless partly are almost nutrients, and organics in rich is digestate The rises. it as slurry the chamber,mixing the of top the at collects and slurry the in forms gas reactor.The the in processes fermentation the in produced biogas the of waste.facilitates thecollection also biodegradable It or and/ blackwater,sludge, of degradation anaerobic the facilitates that chamber airtight an is reactor biogas A electricity orlight. heat, convertedto be can which gases trace other gy. Biogas is a mix of methane, carbon dioxide and ener for used be can that biogas (b) and fertilizer a as used be can that (digestate) slurry digested a (a) produces that technology treatment anaerobic an is digester anaerobic or reactor biogas A S1 Application Level: Biogas Reactor    2: B inlet City Neighbourhood Household IOGAS RE ACT OR biogas pipe Management Level:    Household Public Shared slurr biogas seal y -

Inputs: Outputs: for institutional or public toilet applications. Because Because applications. toilet public or institutional for L 100,000 to up family single a for L 1,000 from vary can Sizes bricks. or containers plastic of out made be can reactors level, household the At materials. organic - pri vatetoilets for public point or access additional withan to connected directly are reactors biogas Often, this countries). isonlyfoundpractice, inindustrialized in (although reactor the heating by achieved be only 57 °C would ensure to the pathogens destruction, but 50 can of temperature thermophilic A 38 °C. to 30 of range temperature mesophilic the in operated are tors - reac biogas Normally, considered. be should days 60 perate climates. For highlypathogenic inputs, aHRT of 15 least at be days hotin climates days 25 and temin - The hydraulic retention time (HRT) in the reactor should can beused. the reactors should be installed close to where the gas expand (like a balloon). To minimize distribution losses, can it Alternatively, gas. of the withdrawal and production with falls and rises dome the reactor, dome ing float- a In pipes. through biogas the transport to used reactor. into flows back the be can pressure slurry The the removed, is gas the When chamber.expansion an into upward slurry the displaces and pressure a exerts Brownwater Sludge Sludge Organics expansion chamber digestate Blackwater System 5 Applicable to: Biogas access cover outlet

reactor 5to shouldbeemptied onceevery 10 years. the inputs, the and be design the on Depending should removed. bottom the to settled have that sand regularly and and carefully prevented. leaksGrit are and corrosion that be so cleaned should equipment Gas and mixed with water ordigestate to prior feeding. shredded be should substrate as used waste Organic sludge. Tank Septic or dung cow adding by e.g., teria, bac- reactor,anaerobic theinoculatedwith be should it ly designed and built, repairs should be minimal. To start Operation &Maintenance If the reactor is proper to humanhealth. flammable gases that, if mismanaged, could be harmful the with associated dangers also are There required. be might treatment further end-use, its infection. on Depending of risk a carries still but sanitized is partially digestate The Health Aspects/Acceptance be longer and the design volume substantially increased. to 15needs belowHRT °C.lowthe Consequently, very is biogas into conversion matter organic of rate the as Biogas reactors are less appropriate for colder climates to andshouldbeavoided degrade inthe substrate. difficult are straw and HRT.material Woodthe reduces stock. Greywater should not be added as it substantially hold with manure if the latter is the main source of feed - be efficient to co-digest blackwater from a single house- animal as such can It waste. household marketor material, organic and manure organic in rich are which biogas substrates, concentrated with obtained of are production levels highest The input. only the is water black if achieved be cannot production gas significant However, biogas. of benefit added the with but ment, - treat of level similar a offers it Tanksince Septic (S.9), a to alternative an as used is reactor biogas a Often, plants. It is best used where regular feeding is possible. treatment wastewater large at sludge of stabilization the for or neighbourhoods small level,in household the at applied be can technology This Appropriateness away the from site. transport and/or use storage, its for made provisions be must there continuous, is production digestate the - - (1996)._ CMS Biogas Technology: ATraining Manualfor Exten- Reading References &Further - - - + + + + + + Pros &Cons Y.,_ Vögeli, Diener, A., C.R., Gallardo, Lohri, S.andZurbrügg, (Ed.),Reuter, A. _ Ulrich, S.(Ed.),Gutterer, B. (Ed.),Sasse,L., H.-P._ Mang, andLi,Z.(2010). Technology Review ofBiogas (1998)._ GTZ Biogas Digest. Volume I-IV. andAdvi Information - Available at: www.fao.org Kathmandu, NP.Services, sion. FAO/TCP/NEP/4451-T. Consolidated Management Available at: www.sandec.ch CH. Sandec),Dübendorf, (Department PracticalCountries. Information andCaseStudies. Eawag C. (2014). Anaerobic Digestion ofBiowaste inDeveloping ough University, UK. Leicestershire, Developing APractical Countries. Guide.WEDC, Loughbor Wastewater Treatment Systems (DEWATS) andSanitation in Panzerbieter, T. andReckerzügel, T. (2009).Decentralised Available at: www.susana.org/library DE. (GIZ) GmbH,Eschborn, für Internationale Zusammenarbeit Gesellschaft Countries. Water, orfor Excreta Treatment andReuse inDeveloping –BiogasSanitation. Sanitation Draft for Blackwater, Brown Available at: www.susana.org/library DE. Eschborn, fürTechnischeGesellschaft Zusammenarbeit(GTZ) GmbH, onAppropriate Technology Service (ISAT).sory Deutsche Limited gas below production 15 °C treatment further require Incomplete pathogen removal, the digestate might Requires design andskilledconstruction expert Low costs operating life Long service ofnutrients Conservation required energy No electrical be builtunderground) can ofthe (most required structure Small landarea ofrenewableGeneration energy -

81 Compendium of Sanitation Systems and Technologies S Functional Group S: Collection and Storage/Treatment .12