DOMESTICi SEPTICi TANKSi FORi TREATINGi SEWAGEiANDi
BIOGASi GENERATION
By
Mawufemoi Modjinou
Ai thesisi submittedi toi thei Departmenti ofi Mechanicali Engineering,
Kwamei Nkrumahi Universityi ofi Sciencei andi Technologyi ini partiali fulfillmenti ofi
thei requirementsi fori thei degreei of
MASTERi OFi SCIENCEi INi RENEWABLEi ENERGYi TECHNOLOGIESi
DEPARTMENTi OFi MECHANICALi ENGINEERING
COLLEGEi OFi ENGINEERING
NOVEMBER,i 2014
, DECLARATION
Ii herebyi declarei thati thisi submissioni isi myi owni worki towardsi thei MSci ini Renewablei Energyi
Technologiesi andi that,i toi thei besti ofi myi knowledge,i iti containsi noi materiali previouslyi publishedi
byi anotheri personi nori materiali whichi hasi beeni acceptedi fori thei awardi ofi anyi otheri degreei ofi
thei University,i excepti wherei duei acknowledgementi hasi beeni madei ini thei text.
Mawufemoi Modjinoui PG63092-11 ………………………………
……………….i Candidate ID
Signature Date
Certifiedi by:
Dr.i Lawrencei Darkwah ………………………………. ………………
Supervisor Signature Date
Certifiedi by:
Dr.i Gabrieli Takyi ………………………………. ……………..
Headi ofi Department Signature Date
Mechanicali Engineering
i
, ABSTRACT
Thisi studyi isi toi designi ai noveli septici tank,i namedi Anaerobici Upflowi Domestici Septici Tanki
(AUDST)i toi recoveri biogasi asi energyi andi treati domestici sewage.i Thei greeni technologyi
proposesi alternatei optionsi toi existingi Domestici Septici Tanksi (DST),i encouragesi
anaerobicallyi pre-i treatmenti toi reducei bacteria,i pollutants,i Totali Suspendedi Solidsi (TSS),i
Chemicali oxygeni demandi (COD)i andi Biologicali oxygeni demandi (BOD)i beforei thei effluenti
isi dischargedi ori isi removedi byi cesspiti trucks.i Studiesi havei showni thati DSTi ini homesi
partiallyi treati ori justi storei sewage.i Again,i thesei DSTi havei toi bei emptiedi fromi timei toi timei
becausei iti lacki featuresi thati willi sustaini anaerobici activityi andi usuallyi thei sludgei isi disposedi
ofi directlyi intoi thei sea,i wateri bodiesi andi eveni intoi openi placesi suchi asi “Lavenderi Hills’’i
withouti anyi treatmenti ori disinfection.i Thesei practicesi causei severei publici healthi andi
environmentali problems.i Toi tacklei thei challengei ati householdi level,i DSTi arei redesignedi toi
treati domestici sewagei withi lessi management,i lowi operatingi cost,i lowi secondaryi dischargei ofi
pollutants.i Thei proposedi newi designi concepti isi operatedi throughi threei (3)i units:i suchi asi
desilting,i anaerobici digestioni andi facultativei filtrationi units.i Thei anaerobici digestioni stagei isi
madei upi ofi bafflei andi anaerobici filteri fori accommodatingi sludgei andi providingi ai morei
intimatei contacti betweeni anaerobici biomassi andi sewagei whichi improvesi treatmenti
performance.i Thei anaerobici uniti isi fittedi withi locallyi woveni basketsi prefilledi withi packingi
materials.i Thei aimi isi toi strengtheni thei biologicali treatmenti processi ati thisi stage.i Thei
Facultativei Filtrationi uniti ofi thei modeli isi alsoi packedi withi filteringi mediai suchi asi gravelsi (3-
6mmi ini diameter)i thati isi lowi ini cost,i andi hasi ai highi durabilityi toi producei effluenti withi
loweri pollutantsi andi suspendedi solidsi contenti toi meeti Ghana’si Environmentali Protectioni
Agencyi (EPA)i standardsi fori thei dischargei ofi domestici effluents.
ii
, ACKNOWLEDGEMENT
Wordsi cannoti expressi myi gratitudei firsti andi foremosti toi Godi Almightyi fori helpingi mei
throughouti thisi project.i Withouti Hisi grace,i thisi worki willi neveri havei beeni completed.i Myi
profoundi thanksi goesi toi myi supervisor,i Dr.i Lawrencei Darkwah,i fori hisi supporti andi guidancei
throughouti thei durationi ofi thisi researchi andi hisi immensei worki ini editingi everyi singlei pagei
ofi thisi document.i Hisi expertisei ini biogasi technologiesi improvedi myi researchi skillsi andi
preparedi mei fori futurei challenges.
Again,i myi sincerei thankfulnessi goesi toi thei latei Prof.i Brewi Hammondi Abeeku,i Directori ofi
Thei Energyi Centrei andi Chairmani ofi thei Energyi Commissioni (EC)i whoi encouragedi mei toi
carryi outi thisi study,i mayi hisi souli resti ini perfecti peace.
Ii alsoi takei thisi opportunityi toi recordi myi sincerei thanksi toi Dr.i A.i Ofosui Ahenkorahi
(Executivei Secretaryi ofi thei Energyi Commission),i Mr.i K.i A.i Otu-Danquahi (Head,i Officei ofi
Renewablei Energyi Promotioni ofi thei Energyi Commission)i andi Mr.i Lesteri Vanlarei (Head,i
Inspectoratei Divisioni ofi thei Energyi Commission)i fori givingi mei thei opportunityi toi worki oni
thisi researchi projecti whilei ati work.i Lasti buti noti thei least,i myi greatesti thanksi goesi toi alli myi
lecturersi fromi thei Mechanicali Engineeringi Departmenti especiallyi Dri Gabrieli Takyii andi Mri
Emmanueli Wendsongréi Ramdei andi alli myi lecturersi fromi Agriculturali Engineeringi
Departmenti mosti especiallyi Dr.i Eliasi Delalii Aklakui andi Dr.i Ahmadi Addoi fori coursesi taughti
andi supporti theyi gavei me.
iii
BIOGASi GENERATION
By
Mawufemoi Modjinou
Ai thesisi submittedi toi thei Departmenti ofi Mechanicali Engineering,
Kwamei Nkrumahi Universityi ofi Sciencei andi Technologyi ini partiali fulfillmenti ofi
thei requirementsi fori thei degreei of
MASTERi OFi SCIENCEi INi RENEWABLEi ENERGYi TECHNOLOGIESi
DEPARTMENTi OFi MECHANICALi ENGINEERING
COLLEGEi OFi ENGINEERING
NOVEMBER,i 2014
, DECLARATION
Ii herebyi declarei thati thisi submissioni isi myi owni worki towardsi thei MSci ini Renewablei Energyi
Technologiesi andi that,i toi thei besti ofi myi knowledge,i iti containsi noi materiali previouslyi publishedi
byi anotheri personi nori materiali whichi hasi beeni acceptedi fori thei awardi ofi anyi otheri degreei ofi
thei University,i excepti wherei duei acknowledgementi hasi beeni madei ini thei text.
Mawufemoi Modjinoui PG63092-11 ………………………………
……………….i Candidate ID
Signature Date
Certifiedi by:
Dr.i Lawrencei Darkwah ………………………………. ………………
Supervisor Signature Date
Certifiedi by:
Dr.i Gabrieli Takyi ………………………………. ……………..
Headi ofi Department Signature Date
Mechanicali Engineering
i
, ABSTRACT
Thisi studyi isi toi designi ai noveli septici tank,i namedi Anaerobici Upflowi Domestici Septici Tanki
(AUDST)i toi recoveri biogasi asi energyi andi treati domestici sewage.i Thei greeni technologyi
proposesi alternatei optionsi toi existingi Domestici Septici Tanksi (DST),i encouragesi
anaerobicallyi pre-i treatmenti toi reducei bacteria,i pollutants,i Totali Suspendedi Solidsi (TSS),i
Chemicali oxygeni demandi (COD)i andi Biologicali oxygeni demandi (BOD)i beforei thei effluenti
isi dischargedi ori isi removedi byi cesspiti trucks.i Studiesi havei showni thati DSTi ini homesi
partiallyi treati ori justi storei sewage.i Again,i thesei DSTi havei toi bei emptiedi fromi timei toi timei
becausei iti lacki featuresi thati willi sustaini anaerobici activityi andi usuallyi thei sludgei isi disposedi
ofi directlyi intoi thei sea,i wateri bodiesi andi eveni intoi openi placesi suchi asi “Lavenderi Hills’’i
withouti anyi treatmenti ori disinfection.i Thesei practicesi causei severei publici healthi andi
environmentali problems.i Toi tacklei thei challengei ati householdi level,i DSTi arei redesignedi toi
treati domestici sewagei withi lessi management,i lowi operatingi cost,i lowi secondaryi dischargei ofi
pollutants.i Thei proposedi newi designi concepti isi operatedi throughi threei (3)i units:i suchi asi
desilting,i anaerobici digestioni andi facultativei filtrationi units.i Thei anaerobici digestioni stagei isi
madei upi ofi bafflei andi anaerobici filteri fori accommodatingi sludgei andi providingi ai morei
intimatei contacti betweeni anaerobici biomassi andi sewagei whichi improvesi treatmenti
performance.i Thei anaerobici uniti isi fittedi withi locallyi woveni basketsi prefilledi withi packingi
materials.i Thei aimi isi toi strengtheni thei biologicali treatmenti processi ati thisi stage.i Thei
Facultativei Filtrationi uniti ofi thei modeli isi alsoi packedi withi filteringi mediai suchi asi gravelsi (3-
6mmi ini diameter)i thati isi lowi ini cost,i andi hasi ai highi durabilityi toi producei effluenti withi
loweri pollutantsi andi suspendedi solidsi contenti toi meeti Ghana’si Environmentali Protectioni
Agencyi (EPA)i standardsi fori thei dischargei ofi domestici effluents.
ii
, ACKNOWLEDGEMENT
Wordsi cannoti expressi myi gratitudei firsti andi foremosti toi Godi Almightyi fori helpingi mei
throughouti thisi project.i Withouti Hisi grace,i thisi worki willi neveri havei beeni completed.i Myi
profoundi thanksi goesi toi myi supervisor,i Dr.i Lawrencei Darkwah,i fori hisi supporti andi guidancei
throughouti thei durationi ofi thisi researchi andi hisi immensei worki ini editingi everyi singlei pagei
ofi thisi document.i Hisi expertisei ini biogasi technologiesi improvedi myi researchi skillsi andi
preparedi mei fori futurei challenges.
Again,i myi sincerei thankfulnessi goesi toi thei latei Prof.i Brewi Hammondi Abeeku,i Directori ofi
Thei Energyi Centrei andi Chairmani ofi thei Energyi Commissioni (EC)i whoi encouragedi mei toi
carryi outi thisi study,i mayi hisi souli resti ini perfecti peace.
Ii alsoi takei thisi opportunityi toi recordi myi sincerei thanksi toi Dr.i A.i Ofosui Ahenkorahi
(Executivei Secretaryi ofi thei Energyi Commission),i Mr.i K.i A.i Otu-Danquahi (Head,i Officei ofi
Renewablei Energyi Promotioni ofi thei Energyi Commission)i andi Mr.i Lesteri Vanlarei (Head,i
Inspectoratei Divisioni ofi thei Energyi Commission)i fori givingi mei thei opportunityi toi worki oni
thisi researchi projecti whilei ati work.i Lasti buti noti thei least,i myi greatesti thanksi goesi toi alli myi
lecturersi fromi thei Mechanicali Engineeringi Departmenti especiallyi Dri Gabrieli Takyii andi Mri
Emmanueli Wendsongréi Ramdei andi alli myi lecturersi fromi Agriculturali Engineeringi
Departmenti mosti especiallyi Dr.i Eliasi Delalii Aklakui andi Dr.i Ahmadi Addoi fori coursesi taughti
andi supporti theyi gavei me.
iii
