SANITARY SEWAGE SYSTEM RECOVERY ASSESSMENT

File: 011696_129_15_031.txt
Page: 031
Total Pages: 71





                      is supported by the data plotted in Figure a. 'A negative
                      correlation exists between the sulfate concentration and
                      the wastewater flow. ie... as flow decreases,, sulfide
                      level increases. ** In the' future, a detailed study
                      should be performed to identify the source of abnormally
                      high sulfate concentrations in the collection system.


                      2. Gro@ of sulfur reducing bacteria. Whatever the
                 source of high concentrations of sulfur in the wastewater,
                 sulfur reducing bacteria must be able to flourish. The septic
                 conditions present in the sewer in conjunction with the high
                 wastewater temperatures are ideal conditions for -the
                 generation of hydrogen sulfide.

                      According to the Kuwait Sanitary Master Plan by Black and
                 Veatch,, there are a number of other conditions prevalent in
                 the Kuwait City system that cause the odor problem to be worse
                 than in other systems.      Among these conditions are the
                 'following:

                      1. oversized laterals and some pressure mains causing
                      low sewage velocity and increasing anaerobic conditions.

                      2.   Surcharged sewers, due both to improper' pumping,
                      station and overloaded sewers.

                      3. Excessive amounts of sand settling out in sewers and
                      pressure mains, providing a good location for'sulfate
                      reducing bacteria to grow.

                      4. High BOD concentrations, which increase the rate of
                      bacterial activity and create septic conditions necessary
                      for the generation of hydrogen sulfide.
                      S. Warm  temperatures in Kuwait sewage,  which   increases
        the rate of bacterial activity increasing the   rate that
                      hydrogen sulfide Is produced. The hydrogen sulfide also
                                                          as
                      becomes  less soluble in water          the temperature
                      increases and is more readily released to the atmosphere.

                      6. High sulfates in the sewage, providing more substrate
                      for bacterial growth if contact time is sufficient.

                      7. Low pH of the sewage, 'favoring the release of the
                      sulfides to the atmosphere.

                      S. Flat sewer slopes, which cause low velocities, longer
                      travel time, and-more extensive anaerobic conditions..

                      9.  Sewer system design features such as excessive need
                                                                           'drop
                      for   pumping and the use of long force ma@,,

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Box ID = BX000000
Unit = CONST ENG LABS  
Parent Organization = CORPS OF ENGS   
Folder Title = SANITARY SEWAGE SYSTEM RECOVERY ASSESSMENT                                                      
Subject = SANITARY SEWAGE SYSTEM RECOVERY ASSESSMENT
Document Number =        129
Image file name = 00000032.tif