Name of the Student : Muheeb Jabari
Name of the supervisor/s :

Dr. Ziad Mimi

Title of the thesis :

Domestie Wastewater Treatment in an Integrated UASB/ algae and duckweed based pond system

Abstract :  

Wastewater management in Palestine has an important priority in order to protect the environment and conserve water resources out of pollution.

Anaerobic wastewater treatment as low cost and energy method in moderate temperature country still need more investigation, on the other hands proper post-treatment after anaerobic reactor should be tested.

This thesis presents the results of a pilot system comprised of one UASB septic tank rector followed by two series of ponds, Algae Based Pond (ABP) and Duckweed Based Pond (DBP). The UASB septic tank has a volume of 350 liters, being operated at two different hydraulic retention time (HRT) of 16.5 and 8 hours. UASB septic tank fed with domestic wastewater from cesspits of Birzeit city, Palestine. Each pond series consist of four equal ponds with a volume of 2700 liters and total area of 12 m2 for each series, being operated at two hydraulic retention time of 32 and 16 days. These different operational conditions caused different pollutants removal efficiencies.

After almost more than 4 months of continuous monitoring, the UASB show good results in terms of COD and BOD removal at HRT 16.5 hours. The (UASB-lagoon) system also produced very good results in terms of COD BOD and nutrients removal. The average COD and BOD removal in UASB septic tank at HRT 16.5 hours where 67.6% and 72% respectively, while preliminary results show dropping of the efficiency to 34.6% and 45% at HRT 8 hours. In ABP at HRT 32 and 16 days another 70% and 49% BOD removal were achieved, where BOD removal in DBP reach average of 80% and 71.6% at HRT 32 and 16 days respectively. PO4 and NH4 removal varied according to type of ponds and flow rate conditions.

In DBP hydraulic retention time of 16 days were quite enough to maintain the BOD concentration below 30 mg BOD/I, while in ABP more than 24 days needed to reach the same value. The UASB/DBP system is very promising alternative for the treatment of domestic sewage in Palestine and other developing countries, since the system achieve good effluent quality in addition to low costs of investment and running costs compared to aerobic treatment systems.