Biological packing
Biological packing
Biofilm is to make micro-organisms attached to the carrier surface of the sewage flowing through the surface of micro-film attached to the carrier in the process of adsorption by organic matter and oxygen to the biofilm within the proliferation and membrane bio-oxidation occurred in the role of decomposition of pollutants.
Introduction
Biofilm has many features: conducive to cell separation; reactor can achieve a higher cell concentration; by optimizing the size of feature vectors can achieve maximum microbial activity; provided simultaneously in the same reactor, the possibility of a fixed different kinds of microorganisms ; processing, high efficiency, resistance to shock loading, small volume, easy operation and management, troubled by activated sludge bulking problem can be eliminated, can maintain a high sludge age, high microbial biomass, hydraulic retention time is short and so on. As the microorganisms are fixed on the carrier, the proliferation of nitrifying bacteria may also slow growth and reproduction of microorganisms. Biofilm biological phase is very rich, formed by bacteria, fungi and other microbial groups, composed of a series of relatively stable ecosystem.
Biofilm wastewater treatment system is a key component of the vector organisms - packing. The development of bio-filler the natural sand and gravel from the past to the present polymer organic materials. Commonly used in organic synthesis is currently filling are: soft filler, semi-soft packing, flexible packing, honeycomb-like packing. As a result there is some filler less biofilm formation, organic matter and low processing efficiency drawbacks. Severe constraints of biological filler in water treatment engineering applications. Therefore, development of new filler to study its application prospects in water treatment is the current hot issue biofilm applied research.
Biological filter media are polypropylene-based polymers, and add fill, such as hydrophobic, hydrophilic, flame resistance, heat resistance, frost resistance, aging resistance, different additives, melt formed by the filament Weld mesh with each other forming the overall structure of the porous filler. Tsinghua University, Water Pollution Control Equipment Quality Supervision and Inspection Center, was hanging on their film and the treatment effect experiments, concluded that "the biological filter media has a good hanging membrane properties. In the bio-reactor packing can significantly increase biomass and obtain good COD removal. "
Table 1 Biological parameters of packing specifications
|
Model
|
Dimensions
(mm)
|
The number of internal water channel
(A)
|
Water channel specifications（mm）
|
Porosity（%）
|
Filler surface area (m2/m3)
|
Life
（a）
|
|
RCB-5225SW
|
500×250
Length of arbitrary *
|
10
|
65×65
|
97~98
|
65~70
|
8~10
|
|
RCB-5225FW
|
500×250
Length of arbitrary
|
10
|
65×65
|
97~98
|
75~85
|
8~10
|
|
RCB-5325SJ
|
500×250
Length of arbitrary
|
36
|
25×25
|
96~97
|
120~140
|
8~10
|
Notice: The biological filter length according to the user requirements. Model suffix means the production for FW iron fillers are added to fill with a positive charge.
2, physical characteristics
Table 2, bio-physical properties of filler
|
Material
|
Density（g/cm3）
|
wire diameter
（mm）
|
Porosity
（%）
|
Compressive strength（kPa）
|
Elongation at Break（%）
|
Acid and alkali
|
|
Polypropylene
|
≈1.0
|
Ø1.5~Ø0.6
|
96~99
|
>4.0
|
3.60~3.97
|
Stability
|
|
