| book details |

Controlling Biofouling in Seawater Reverse Osmosis Membrane Systems

By (author) Nirajan Dhakal

| on special |

normal price: R 3,864.95

Price: R 3,671.95

| add to trolley |

| book description |

Seawater desalination is a rapidly growing coastal industry that is increasingly threatened by algal blooms. Depending on the severity of algal blooms, desalination systems may be forced to shut down because of clogging and/or poor feed water quality. To maintain stable operation and provide good feed water quality to seawater reverse osmosis (SWRO) systems, ultrafiltration (UF) pre-treatment is proposed. This research focused on assessing the ability of UF and other pre-treatment technologies to reduce biofouling in SWRO systems. An improved method to measure bacterial regrowth potential (BRP) was developed and applied at laboratory, pilot and full scale to assess the ability of conventional UF (150 kDa) and tight UF (10 kDa) alone and in combination with a phosphate adsorbent to reduce regrowth potential and delay the onset of biofouling in SWRO. The improved bacterial regrowth potential method employs a natural consortium of marine bacteria as inoculum and flow cytometry. The limit of detection of the BRP method was lowered to 43,000 Â± 12,000 cells/mL, which is equivalent to 9.3 Â± 2.6 Âµg-Cglucose/L. The reduction in bacterial regrowth potential after tight UF (10 kDa) was 3 to 4 times higher than with conventional UF (150 kDa). It was further reduced after the application of a phosphate adsorbent, independent of pore size of the UF membrane. Pilot studies demonstrated that the application of tight UF (10 kDa) coupled with a phosphate adsorbent consistently lowered the bacterial regrowth potential and no feed channel pressure drop increase was observed in membrane fouling simulators (MFS) over a period of 21 days. The study also showed that non-backwashable fouling of UF membranes varied strongly with the type of algal species and the algal organic matter (AOM) they release. The presence of polysaccharide (stretching -OH) and sugar ester groups (stretching S=O) was the main cause of non-backwashable fouling. In conclusion, this study showed that an improved BRP method is suitable for the assessment of SWRO pre-treatment systems and it can be a useful tool to develop potential strategies to mitigate biofouling and improve the sustainability of SWRO systems.

| product details |

| other options |

Normally shipped | Usually dispatched in 3 to 4 weeks as supplier is out of stock
Readership Age |

Normal Price | R 5,121.95
Price | R 4,865.95 | on special |

| add to trolley |

| back |

| your trolley |

To view the items in your trolley please sign in.

| sign in |

| specials |

Bonsai Success in Southern Africa

Carl Morrow
Paperback / softback
160 pages
was: R 320.95
now: R 288.95
Stock is usually dispatched in 6-12 days from date of order

In this uniquely Southern African book, Carl Morrow and Keith Kirsten guide readers step by step into the magical realms of bonsai as a hobby, horticultural practice and art form.

| more |

| add to trolley |

Fifteen Dogs

AndrÃ© Alexis
Paperback / softback
176 pages
was: R 280.95
now: R 252.95
Available from overseas. Dispatched in aprox 4-8 weeks as local supplier is out of stock

A pack of dogs are granted the power of human thought - but what will it do to them? A surprising and insightful look at the beauty and perils of consciousness.

| more |

| add to trolley |

The Ballerina and the Bull: Anarchist Utopias in the Age of Finance

Johanna Isaacson
Paperback / softback
288 pages
was: R 306.95
now: R 275.95
This title will take longer to obtain, and should be delivered in 6-8 weeks

Our moment has seen the resurgence of an anarchist sensibility, from the uprisings in Seattle in 1999 to the Occupy movement of 2011.

| more |

| add to trolley |