الفهرس 
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Abstract
Based on the experimental program executed in this research, and the results
obtained from the two stages UASB/MBR1 and the single stage MBR2 treatment
systems according to the procedures described in chapter four and five, the
following conclusions have been reached:
1. The intermittent operation of the UASB is very appropriate pre-treatment
solution for the submerged MBR system for that:
i) It has achieved very reasonable removal efficiencies for COD coarse
suspended fractions with average value of (61%±13%), and COD
colloidal fractions with an average value of (37%±4%), and suspended
solids (51%±12%) which could affect extremely the cake resistance
biofouling of MBR.
ii) According to the obtained results and removal ratio for the dissolved
fractions of COD, the biodegradability for the UASB continues also
during the feedless period with an average removal ratio of
(26%±11%).
2. MBR1 achieved higher performance rather than MBR2 under both moderate
(20-25 L/m2/hr) and high flux rate operation (40-50 L/m2/hr) regarding to :
i) Longer steady operation periods under high flux rates (2.3 times of
magnitude).
ii) Longer steady operation periods under moderate flux rates (3 times of
magnitude).
iii) Steady flux rates.
iv) Total clean water flux recovery varied between (96.1% - 98.5%) for
MBR1 compared with (49.3% - 83.3%) for MBR2.
v) Gradual TMP increasing rates associated with higher permeability
rates.
3. The cleaning rate is reduced for the two stage UASB/MBR1 system with 65%
saving of chemicals required and avoiding the bad effect of the used
chemicals on the life time of the membrane units.
4. the two stage UASB/MBR1 systems shows a very high removal efficiencies
regarding the biological oxygen demand (BOD5
20), the total suspended solids
(SS), and chemical oxygen demand (COD) rather than single stage MBR2
system, i.e., the average effluent concentration of BOD5 was 4 mg/l with a
removal ratio of 98.6 % and the effluent concentration of COD was 46 mg/l
with average removal ratio of 90 % and the suspended solids on the effluent
were not detective (<2 mg/l), under normal operation conditions.
5. The two stage UASB/MBR1 system shows a higher resistance against
organic shock load due to the anaerobic efficiency with the high organic
loading rate. The two stage UASB/MBR1 system achieved average removal
efficiency of 92.3% for COD total compared with 62.3 % for MBR2 under
shock organic load of.
6. The cleaning procedure of MBRs could be flexible and varied according to
the characteristics of the raw wastewater being treated and also the
pretreatment system, i.e. no need to use oxalic acid with domestic sewage, as
there is very low content of inorganic fouling occurred.
7. The proposed combination (two stages UASB/MBR1) system achieved a
double profit for both stages as a pre and post treatment maximizing the
benefits and overcoming the drawbacks for each system like, the required
treatment efficiencies, the required energy cost , amounts of cleaning
chemicals