| The Upflow Anaerobic Sludge Blanket Systems also relies on upflow velocities to suspend anaerobic solids. However, upflow velocities are much lower than utilized in the AFB process since no carrier material is provided. Instead the anaerobic active mass tends to form a granular type of sludge which assists with its retention in the anaerobic reactor. Various differences between UA Sludge Blanket Systems reactors were noted on visits to various European facilities. Some reactors are constructed of concrete; others of steel. Some reactors are rectangular; others are cylindrical. Some are moderate height (6 m ); one extended 20 m high. The reactors generally had various proprietary designs for distributing influent and recirculated flows at the bottom as well as three-phase (effluent, solids, gas) separators at the top. |
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AREA OF SLUDGE BLANKET APPLICATION
The UA Sludge Blanket Systems concept which has been traditionally used for treatment of liquid effluents has been successfully modified for treatment of liquid waste with high concentration of suspended solids like Abattoir waste waters as well as solid waste like Poultry droppings, Kitchen Waste, Vegetable Waste.
LOADING RATES
Type of Wastewater |
Maximum loading rate
(kg COD / m3-day) |
COD Reduction
(%) |
Sugar beet factory |
30-32 |
75 |
Potato Processing |
40 |
84 |
Potato starch production |
30 |
75 |
Vegetable canning |
10-20 |
60-80 |
Yeast factory |
14 |
70 |
Dairy factory |
15 |
80 |
Slaughter House |
10 |
55 |
Rendeering plant |
6 |
63 |
Distillery waste |
11-17 |
45-65 |
Wood ethanol stillage Currant finishing |
16 |
86 |
Wastewater |
10-12.5 |
93-95 |
DESIGN FEATURES
The Chempure Sludge Blanket Systems is initiated by:
i, Soluble organic components in the waste are partially biologically converted to volatile fatty acids (VFAs) in a pre- acidification. The residence time required for acidification is four to six hours.
ii, The pH of the wastewater is adjusted and nutrients are added, if required.
iii, The conditioned wastewater is introduced into the reactor, where the conversion of soluble organics to VFAs is completed and the VFAs subsequently converted to an energy rich biogas of methane and carbon dioxide.
iv, Some treated wastewater may be recycled to return alkalinity to the system.
v, The biogas may be used in a boiler or other devices or burnt in a flare.
