Double Vault Composting Toilets雙坑堆肥廁所設(shè)計(jì)建造 2

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DoubleVaultCompostingToilets雙坑堆肥廁所設(shè)計(jì)建造2

Double-VaultCompostingToilets******************************************-*******-****-************************LikeanyDVCtoiletwhichiswatertight,thisdesignmayexperiencedifficultyiftoomuchurineaccumulates.Onesourcereportsthatexcessurinewillrequiremorefrequentturningofthepile(41),whileanothersimplyrecommendsurineseparation.(42)Inanyevent,itisadvisedtoaddaquantityofdrysawdust,shreddedleaves,ricehullsorchaff(alaearthcloset)eachtimethetoiletisused.(43)CriticsoftheFarollonesprivyhavepointedoutthatitshouldworkwellbutunfortunatelyitinvolveshandlingoffreshexcretaanditisthereforeunacceptableforhealthreasons.(44)Thehealthhazardofhandlingtheexcreta,evenifonlyforafewminutesamonth,mustofcoursebeweighedagainsttheincreasedpathogendestructionachievedbyaerobiccomposting.TherehavenotbeenmanyattemptstoimplementaerobicDVCtoiletsindevelopingcountries,butasignificantnumberhavebeenbuiltinnorthernCalifornia(largelybyowner-builders)andthestateauthoritieshaveplayedanactiveroleinmonitnringexistinginstallations.Itisveryprobablythatproperlyconstructedandmaintained(myitalics),thecompostingprivyisasafe,lowcost,non-pollutingandodorfreealtemative.(43)Beforedismissingthisoptionitshouldberememberedthat,astheWorldBankwarns,allDVCtoiletsprobablyrequireanextremelyhighdegreeofusercareandmotivation...forsatisfactoryoperation.(9)7.FOURTYPESOFDVCTOILETS:GENERALCONCLUSIONSIhavedescribedfourdifferenttypesofcategoriesofDVCtoilets;itmightbeusefulatthispointtosummarize.Onthebasisoftheevidenceinthetechnicalliterature,thepour-flushDVCtoiletseemstobethemostall-aroundsuccessfulsolution.Itdoesnotrequirereinforcedconcreteorventpipes.Itgivestheconvenienceandhygienicstandardofawater-bornesystematextremelylowcost,whilepreservingtheimportantcharacteristicofallcompostingtoilets,thatofprovidingfertilizerforreuse.Thepour-flushversionissimpletousesinceorganicmaterialisonlyaddedoncepercycle,ifatall,andtheuserdoesnotneedtoconcernhimselfwithdaytodayadjustments.ThefactthatthecompostingvaultsareoffsetmeansthatconstructioncostsareprobablythelowestofallDVCtoilets(seesection9:ECONOMICS).Thedisadvantageofthepour-flushDVCtoiletisthatpropercompostingmaybedisruptedbyrainflooding,andenvironmentalpollutionmayresultifthereisahighwatertable.Inthateventthewater-tightabovegroundDVCtoilets,eitheraerobic,oranaerobicwithurineseparation,arepossibilities.Botharemorecomplicatedtooperateonaday-to-daybasis,botharemoresusceptibletomalfunction,andone,theaerobicDVC,presentsparticularproblemswithhandlingfreshexcreta.Oneadvantageofthewater-tightDVCtoiletsisthatallthematerialsarecontainedinthecompostingvault,andconsequentlythenutrientvalueofthefertilizerislikelytobehigherthanwithDVCtoiletsthatinfiltrateurineintotheground.However,wherewaterisusedforanalcleansing,eitherbytraditionorreligiousprescription,awater-tightDVCtoiletcannotbeused.Onthefaceofit,theDVCtoiletwithorganicrefuseseemstheleastattractivesolution.Theconstructioncostishighsincethetoiletislocatedoverthepit.Thecostofventpipesandduplicatedsquattingplatesmustalsobeconsidered,andtheprovisionoforganicrefusedailyalsomayrepresentaproblem.(15)Inanysituationwheresoilconditions,aswellasculturalmores,pennittheuseofaDVCtoiletwithorganicrefuse,thepour-flushDVCtoiletwillprobablybealessexpensive,andhigherquality,alternative.Inaridareas,orwheneverwaterisinshortsupply,thesopasandasisprobablythe19EnvironmentalSanitationReviews,December1981********************************************************************************mostsuccessfulDVCtoiletwithorganicrefuse.8.RURALGRURBAN?AreDVCtoiletsstrictlyaruraltechnology,ordotheyhaveapplicationincitiesandtowns?TheVietnameseinstallationshavebeenalmostcompletelyxural,whichhasledsomeobserverstoassumethatthissolutionshouldbeconfinedtovillages.Othershavequestionedtheavailabilityoforganicrefuseintonns,aswellasthelackofsufficientdemandforfertilizer.(g)ThelackofsolidwasteremovalinmostlowincomeareasindevelopingcountrycitieswouldseemtoarguethecaseforurbanDVCtoiletsasusefulgarbagedisposal.(16)Thepresenceofdomesticgardensinmostsiteandservicesprojectswouldpresumablystimulatedemandforthecompost.Thepour-flushDVCtoiletsinIndiahavebeeninstalledlargelyintownsandcities,forinstanceinPatnaandRanchi,bothcitiesofcover100,000persons.TheUNDPGlobalProjectislikewiseaimedaturbancommunities.TheRECIIDVCtoiletinBotswanaisbeingusedinlowrisehighdensityhousingandanurbanDVCprojectisunderwayinMexico.(13)Thepour-flushlatrinesinstalledbySulabhShauchalayahavebeeninstalledinurbanhouseswiththecompostingvaultsinthecourtyard,andinsomecasesevenwithinthehouse.Themainconstraintonusinginfiltration-typetoiletsinurbanareasisusuallythoughttobegroundcontamination.TheWorldBankconsidersthatthemaximumdensityforsuchsystemsis500-600personsperhectare(two-storyhouses),buthastenstopointoutthatpitlatrineshavebeenfoundtooperatesuccessfullyathigherdtnsities.(45)Caldwell,sometimeago,pointedoutthatthecontaminationfromdrypitlatrineswascontainedinasmallarea(46);arecentstudyinKenyafoundthatpitlatrineswerebeingsuccessfullyusedatrelativelyhighdensities.(47)Pathakpointsoutthatsincethecompostingvaultissoshallow,inthepour-flushDVCtoilet,thechanceofgroundwaterpollutionisvirtuallynil.(25)ThequestionofwhetherDVCtoiletscanbesuccessfullyusedinurbanareasisparticularlyimportantastherearesofewlowcosturbanoptions.Mosturbanalternativestoconventionalundergroundsewers,suchassmalldiametersewersorcartagtsystems,arestillextremelycostly.(48)CurrentexperienceindicatesthatthemainconstrainttotheurbanuseofappropriateDVCtoiletsismorelikelytobeaccesstogroundlevel,andnotdensityperse.Sincemostlow-incomeurbanhousinginthelessdevelopedcountriesisl-2storeys,thepotentialforurbanDVCtoiletsisquitelarge.9.ECONOMICSTheconstructioncostofaDVCtoiletwillvaryconsiderablywithlocallaborandmaterialscosts.Likewiseimportantwillbethemodeofimplementation,whetheruser-built,locallycontractedorpartofalargesiteandservicesproject.TherearenocostfiguresfortheVietnamesedesign,butasitisusuallybuiltoutoflocally-availablematerials(stone,earth,mud-driedbrick),andapparentlybytheusers,itscostcouldbeexpectedtobeverylow.(36)Pate1rtprotsthatthecostofthegopuriislessthanUS$25,whilethesopasandascostUS$15-20.(21)In1972,sopasandaswerebuiltbytheusersforamaterialcostofUS$10,(22)whilepour-flushDVCtoiletswerebuiltforUS$40.(49)Theestimatedcostofthewater-sealDVCtoilettobe20Double-VaultCompostingToilets-__-__--__builtbytheUNDPGlobalProjectinIndiaisUS$40-50,dependingonthematerialsanddesign.(SO)Ontheotherhand,DVCToiletswhichhavebeenbuiltinAfricahaveprovedtobemuchmoreexpensive.TheRECIIinBotswanahasanestimatedcostofUS$200(19),whiletheWHO-typeconcreteDVCtoilet,builtlikewiseinBotswanaaspartofadifferentresearchproject,isreportedtohavecostaboutUS$400.(14)ThedifferencebetweentheAfricanandtheIndiancostsisduepartlytoincreasedmaterialcostsinAfrica,andalsotothelongerexperiencewithDVCtoiletsinIndia.ThefactthattheIndianDVCtoiletsusuallyutilizeoffsetpitsandrarelyuseconcreteundoubtedlyalsoaccountsfortheirlowercost.AnyDVCtoiletwhichrequiresreinforcedconcrete,ventilationpipes(usuallygalvanizedmetal),adoublesquattingplateorextensiveblockworkwillprobablybetoocostlyformostlow-incomeusers.Alternativesolutionstosanitationmayrequire,inadditiontounconventionaltechnologies,unconventionalimplementationstrategies,basedincreasinglyonlocalresourcesandinitiative.Pathakreportsthatpublicpour-flushDVCtoiletsareoperatedbyalocalprivateorganizationinPatna,India.(49)Theseinstallations,20-40stalls,areopen24hoursaday.Theuserpaysfortheuseofthetoilet-aboutonecent-forwhichhereceivesalsosoappowder(womenandchildrendonotpay).Thismoneyisspentonmaintenance,caretakerswagesandcleaningmaterials,andsinceabout100personsperdayuseeachstall,themunicipalityisnotrequiredtospendmoneyonmaintenanceandrepairs.Thefinancingofwaterbornesanitationisexpensiveandfarbeyondtheeconomicmeansofthelow-incomeuser-whichisonereasonwhycountriessuchasIndiaareincreasinglyturningtodryoptions,suchastheDVCtoilet.ThelargescaleimplementationofDVCtoiletswillstillrequiresomesubsidyintheformoflowinterestloanstohouseholders,orinsomecasesoutrightgrants.RoyestimatesthattheannualinterestandrepaymentofloanchargesfortheIndianpour-flushDVCtoiletwillbeaboutUS$5perhousehole,whichisalmostthesameasiscurrentlypaidtoscavenger.(50)Otherprojectshavebeendescribedwheretheentirecostofthepour-flushDVCtoilet,uptotheplinth,havebeencoveredbymunicipalsubsidies.(49)10.DVCTOILETSANDEXCRETAREUSEAfinalpointneedstobemadeconcerningtheselectionofDVCtoilets.Unliketheaqua-privyortheseptictank,theDVCtoiletisnotatechniqueforexcretadisposal,butratherforexcretareuse.Thisisavitaldifference.Aspartofacomprehensiveprogram(asinVietnam),theDVCtoiletcanproducenotonlyhealthimprovementsbutalsoagriculturalbenefits.AsIhaveshown,thehistoricfunctionoftheDVCtoilet,andofitspredecessors,hasbeencloselylinkedtofertilizerproduction,anditislikelythatthiswillcontinuetobethecase,whetherthecompostisusedinthefieldorinthegarden.ItisunlikelythattheDVCtoiletcan,orshouldbe,divorcedfromthisfunction.TheDVCToiletcanproducesubstantialeconomicbenefits.TheIndianNationalEnvironmentalEngineeringInstitutehascalculatedthecashvalueofcompostproducedbypour-flushDVCtoiletsisaboutUS$10peryear,inwhichcasethecapitalcostofconstructioncouldberepaidinfiveyears.(26)Royestimatesthatthesaleofcompostcouldpayformaintenanceofpour-flushDVCtoilets.(50)Whetherornotthecomposthasaneconomicvalue,itisobviousthatinbothIndiaandVietnametheproductionoffertilizerisanimportant21EnvironmentalSanitationReviews,December1981_-_*reasonforthechoiceofDVCtoilets.TheadoptionofDVCtoiletsthusmightbesaidtodependonademandforcampostedhumanwastesforfertilizer,but,importantly,thisdemandmaybeactualorpotential.Insocietieswherehumanexcretaisusedinagriculture,suchasIndia,ChinaorVietnam,aDVCtoiletrepresentsamodificationofcurrentpractice,ratherthananewattitudetowardsreuse.Ontheotherhand,inmostpartsofAfricarawexcretaisrarelyusedasfertilizer,andinLatinAmerica,althoughsewageisusedforirrigation,theideaofreusinghumanwastesdirectlyiscertainlynottraditional.Insuchcultures,thedemandforcompostedexcreta,whilenotactuallypresent,maybestimulatedoncethetechnologyisaccepted,andthenumberofDVCinstallationsincountrieswithoutarecenttraditionofexcretareuse,suchasTanzania,Botswana,Mozambique,Argentina(51).Guatemala,MexicoandtheUnitedStates,indicatethatDVCtoiletsarebynomeansaregionaltechnologyl.Ofcourse,theseinitialeffortshavenotalwaysmetwithsuccess.ItisreportedthatinTanzaniamanypeopleloatheworkingwithcompostedhumus,whichmanypeopleregardasfeces(27),andthatinBotswana,traditionalattitudesmilitateagainstreuseofhumanwasteonanindividualbasis.(14)Nevertheless,asIwugo(52)pointsout,itwouldbeprematuretomakeaqyjudgenentsaboutthereuseofcompostedhumanexcretainagricultureinAfricasincetherearesofewinstancesofsuccessfulcaapostingactuallyinoperation.Mosttraditional(negative)attitudestowardsthereuseofexcreta(inAfricaorelsewhere)havebeenformedontheexperienceofraworpartiallydigestedhumanexcreta,notcompost.Whetherornotthelatterwillmeetwithsimilarresistanceremainstobeseen.Itispossiblethatundercertaincircumstances,theDVCtoiletmayhaveadvantagesthatoutweighthefactthatreuseisnotthemainconsideration.TheRECIIisbeingbuiltinBotswana,whichhasnotraditionofexcretareuse.Nevertheless,theDVCtoilethasanumberoffeaturesthatmakeitpreferabletothesinglepitlatrine.Thefactthattherearetwopitsmeansthatexcretahandlingismuchsaferandmorehygenic.Evenwhenvaultemptyingistobedonebymunicipalauthorities,asisthecasewiththeRECII,theuseoftwovaultsgivesmuchmoreleewayastoemptyingschedulesthandoesasinglecompartmentcartagesystem.Finally,canpostedexcretaisadry,non-smellingmaterialwhichisconsiderablyeasiertohandlethanliquified,partiallydecomposedexcreta.Thisfactmayalsoaffectpopularattitudestohandlingcompostedexcreta,oncethesystemisputintouse.DVCtoiletswithurineseparationhavebeenintroducedtoGuatemalaandafteroneyearexperienceanumberofinterestingobservationshavebeenreported.(38)Acceptanceofthisnewdevicewasoftenbased(naturallyenough)onperceivedutility.Forinstance,peoplewholivednexttofieldsinwhichtheywereusedtodefecatedidnotseemuchpointinbuildingatoilet.Ontheotherhand,whenpeoplelived200-400metersawayfromadefecationarea,%nthusiasmforthistypeoftoiletisastonishing.Thestudyteamalsofoundaconsistentcorrelationbetweenthephysicalappearanceoftheprivyenclosureandinterior,andthemicrobiologicalpropertiesofthecanpost.TheclearimplicationisthatpeoplewhoareabletokeeptheprivycleanandtidyarealsoabletofollowtherequireddirectionsforoperatingtheDVCtoilets.ThesuccessfulimplementationofDVCtoiletsoftenseemstodependasmuchonsupervision,educationandpropagandaasonthedesignofthetechnology.I)ucmakesthepointtk3.periodicinspectionsoftoiletsmustbemadewith*bcmendatio~giventotheuseronanyshortcaaingsthatneedtoberectified.(37)ThetilabhShauchalayaprovidesafiveyearguaranteetotheownersofitspour-flushDVCsandgivesfreeinspectionsandrepairsandwillevacuatethevaultifrequested.(25)CHAT,inGuatmla,encouragedeachfamily22Double-VaultCompostingToilets--__-____________________usingaWCtoilettoappointoneofitsmembersinrotatingfashiontomakeperiodicchecksonthestateofthetoilet.(38)TheGandhiSmarakNidhicontacted90%ofDVCowners(500morethanonce)duringaprogramwhereover20,000toiletswerebuilt.(22)Lawsandregulationsmayalsoplayarole:thegovernmentofBiharimposedafineorone-monthimprisonmentonpersonswhodidnotconvertbucketlatrinesintopour-flushDVCtoilets(forwhichsubsidiesandloanswereavailable).(49)Therolethatproscriptiveregulationsplayed,andcontinuetoplay,inimprovingsanitationintheindustrializedcountriesiseasilyforgotten.Theiradoptionofhygienicstandardsinsanitation,andthemaintenanceofthesestandards,wasneitherspontaneousnorvoluntary.Thereisnoreasontobelievethatimprovementsinsanitationinthedevelopingcountriescanbeachievedwithoutsimilarenforcementofappropriatestandardsandpractices.11.DVCTOILETSELECTIONArecentWorldBankreportonsanitationtechnologies(9)includesathreestagealgorithmfortechnologyselection.ThesecondstageconcernsDVCtoilets,oneoutofelevenalternatives.SincethispaperhasexploredDVCtoiletsingreaterdetail,Ihavedevelopedacomplimentaryalgorithm(Fig.12)forselectingoneoutofthefourDVCtoilettypes,whichcanbeinsertedintheappropriateplaceinthelargeselectionalgorithm.IHbtOTHEROPTIONSNoDVCWITHORGANICREFUSEbncompostturningkmwwallylnlDVCAEROBICp;;fNrlTHSEPARATIONFii.12AlgorithmforDVCToiletSelection23EnvironmentalSanitationReviews,December1981--__TheselectionofaparticulartypeofDVCtoiletdependsonanumberofexternalvariables,aswithanysanitationoption.MostDVCtoiletsaredryandwilloperatewellwithanextremelylowlevelofwatersupplyexceptforpossiblythepour-flushDVCwhichmightrequireayardtap.SincemostoftheDVCsinfiltrateurineintotheground,soilconditionmustbeaconsideration,thoughawatertableevenwithin0.5metersofgroundleveloughtnottoimpairproperfunctioning.WatertightDVCtoilets,suchastheFarallonesorVietnamesetype,canbebuiltonimpermeablesoil.HousingdensitywillalsolimitthetypesofDVCtoiletsused,thoughconsiderablylessthanitwouldpitlatrinesorseptictanks.Fromastrictlyenvironmentalpointofview,mostDVCtoiletscouldbeusedinhighdensity,ground-relatedhousing.Whetheranewtechnologysuchascompostingtoiletsisintroducedthroughprivateinitiative,orbystateedict,itislikelythattheprocessofimplementationwillbelengthy.McMichael(34)reportsthattheproliferationofDVCtoiletsinVietnamwasnotwithoutsetbacksandacceptancewasbynomeansimmediate,butrequiredapatientcampaignofexplanationandarrangementjointlyconductedbyhealthandpoliticalworkers.Therelationshipbetweeneducationalprogramsandtechnologicalinnovations,inafieldsuchassanitation,iscrucial,andthoughthefocusofthispaperhasbeennecessarilyonmatterstechnological,thatisnotmeanttosuggestthattheDVCtoiletisinwWYatechnologicalfix.ItwouldbewelltorecallthewarningofJohnWallace(53),aBritishengineerworkinginBombayattheendofthenineteenthcentury:Thereisnobestkindoflatrineunlessacultivatedfieldcouldbesodesignated;but,astraditionalcustomleavesitsmarkevenuponoursimplestnaturalfunctions,thedesignofagoodlatrineinvolvesaveryconsiderableknowledgeofhumannatureaswellasofnaturalphencmena.ACKNOWLEDGEMENTSIwishtoacknowledgetheassistanceofmyfriendandcolleague,Prof.VikramBhatt,whoprovidedmushusefulinformationontheIndianexperienceswithDVCtoilets.InformationwasalsoprovidedbyBlakelyBruce,Dr.KrisnoNimpunoofBouwcentrumInternationalEducation,Dr.MichaelMcGarry,aswellasJohnM.KalbermattenandRichardMiddleton,oftheWorldBank.ABDUTTHEAUTHORWITOLDRYBCZYNSKIisAssociateProfessorandDirectorofMinimumCostHousingStudiesatMcGillUniversity,Montreal.HeistheauthorofLowCostTechnologyOptionsforSanitation(I.D.R.C.,1978)andPaperHeroes:AReviewofAppropriateTechnology(Anchor/Doubleday,1980).NOTEThedimensionsgivenonthediagramsareapproximateandforcomparativeuseonly.24Double-VaultCaupostingToilets___-__-__-__-_.REFERENCES1.2.3.4.5.6.7.8.9.10.11.12.13.14.15.16.17.NIMPUNO,K.(19741,mSystem:QSeriousBottleneckidPlanning,DailyNews,March5,DaresSalaam,Tanzania.REID,G.(1905).PracticalSanitation:AHandbookforSanitaryInsnectorsandOthersInterestedisSanitationLondon.e-MOORE,E.C.S.(1898),SanitaryEngineering,London.G.L.D’CMBRAIN,ConversationwithAuthor.POORE,G.V.(18933,EssaysonRuralHygiene,London.--HOPKINS,E.S.(1958),mdPracticeLfSanitation,Baltimore.HARDENBERGH,W.A.(19241,HomeSewageDisposal,Philadelphia.HOWARD,A.(19351,TheManufactureofHumusbytheIndoreProcess,L.RovalSot.Arts,Vol.84,No.25.--KALBERMATTEN,J.M.etal.(1980),AppropriateTechnologyforWaterSupplyandSanitation:APlanner’sGuide,WorldBank,Washington,D.C.,December.YAGER,R.(1979),FeasibilitystudyoftheUseofCornpostingToiletsin-7--UrbanColoniasofOaxaca,Mexico,Unpublishedreport,CornellUnity’;Ithaca,NewYork.--WAGNER,E.G.andLANOIX,J.N.(19581,ExcretaDisposalforRuralAreasand-sSmallComities,WorldHealthOrganization,Geneva.WINBLAD,U.andXILAMA,W.(1981),SanitationWithoutWater,SwedishInternationalDevelopmentAgency,Stockholm.ANON.(1980),CotorreoContraUContaminacion,TechnologiaAlternative,June,Merida,Mexico.-BLACKMORE,M.D.etal.(19781,ChoiceofTechnologyinBotswana,Sanita-tioninDevelopingCountries,ArnoldPacey,ed.,NewYork.m-GURAX,R.S.(1978),FinalReportsProjectTanzania,=Africa,tAlternativeWasteDisposalMethodsUnpublishedreport,March,InternationalDevelopPlentResearchCentre,Ottawa.SIMBEYE,E.K.(1981),On-SiteExcretaDisposalTechnologies,SanitationDeveloDingCountries,InternationalDevelopmentResearchCentre,Ottawa.WRIGIR,A.M.(1977),RuralLatrinesinIndia,June,andTechnology,Kuasixna.UniversityofScience2sEnvironmentalSanitationReviews,December1981_-)___~18.19.20.21.2-4..23.24.25.26.27.28.29.30.31.32.33.34.35.CARROLL,R.F.(1980).ImprovingthePitLatrine,Paperpresentedat6thWaterandEngineeringinDevelopingCountriesConference,March,LoughbTough,U.K.WILSON,J.G.(1981),minCountries,ThePIPandRECIILatrines,SanitationinDevelop-InternationalDevelopmentResearchCentre,Ottawa.BRANDBERG,B.JERlBlIAS,M.(1981).HousingSanitation,Mozambique,SanitationinDevelopinnCountries,InternationalDevelopmentResearchCentre,Ottawa.PATEL,I.(1970).SafaiMargdarshika(AGuideBookonSanitation),NewDelhi.ANON.(1972),EvaluationRenortontheVillageSanitationSchemeofthe-----GandhiSmarakNidhii@Maharashtra,UnpublishedreportoftheProgrammeEvaluationOrganization,PlanningCommissionGovernmentofIndia,NewDelhi.TODANKAR,H.N.(1981),Latrine-AToolforBmancipationofScavengers(BhagiMuktil),2.BiowasteTreatm.Vol.I,No.1.H.N.TODANKARinconversationwithVIKRAMBHATT(1981).PATHAK,B.(1980),LatrineConversionProgram,PaperpresentedtoNation-alWorkshopsSanitation,Colombo,SriLanka,Jan.23-25.KSHIRSAGAR,S.R.(1981),NEERILatrineasaToolforRecyclingofNutrientsfromHumanWastesinRuralAreas,2.BiowasteTreatm.,Vol.I,No.1.FCGEL,M.(1977),ChemicalAnalysisofClivusMultrumCompost,ReportofClivusMultrumInc.,Cambridge,U.S.A.,February.MCGARRY,M.G.STAINFORTH,J.eds.Campost,FertilizerandBioRasProduc-tionfromHmanandFarmWastesinthePeople’sRepublicofchina,Interna-~aif~e~ResearchCentre,Ottawa.MORSE,E.S.(19611,JapaneseHousesandTheirSurroundings,NewYork,SONNIN,H.C.(1806),Forslagtilen--ForandringiVanhusenesaRenovation,Copenhagen.KIRA,A.(1966),TheBathroom,Ithaca,N.Y.UrineseparatingtoiletseatshavebeenbuiltandtestedbystudentsintheExperimentalLow-CostConstructionUnitatFloridaAMUniversity,underthedirectionoftheauthorandProf.L.Birch.ICHAEL,J.K.ed.(1976),HealthintheThirdWorld:StudiesfromViet--e)Nottingham,U.K.MGWXHAEL,J.K.(1978),TheDoubleSept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