PRODUCTION AND EQUIPMENT
POROUS PERMEABLE CERAMIC FOR FINE BUBBLE
WASTE WATER AERATION SYSTEMS IN AERATION TANKS
B. L. Krasnyi,
V. P. Tarasovskii,
A. B. Krasnyi,
and A. M. Uss
Translated from Novye Ogneupory, No. 10, pp. 7 – 12, October 2010.
Original article submitted July 28, 2010.
Results are provided for a study of the creation of ceramic materials for aerator nozzles. The effect of porous
ceramic pore size and air bubbles emerging from it are considered. Physicotechnical properties of porous per
meable material specimens for aerator nozzles are provided. An experiment is performed for determining the
effect of air flow rate, effective pore size and specimen thickness on the oxygen content in water. Production
of the inserts developed is organized.
Keywords: aeration, aeration tank, disperser, porous permeable ceramic, pore size, air flow rate.
The Russian Federation is one of the richest countries in
the world with respect to water resources. The importance of
these resources for providing social and economic develop-
ment of the country cannot be overestimated. However, cur-
rently the state of many water management systems and wa-
terworks is very unsatisfactory . Analysis of the state of
water objects indicates that almost all water sources, both
surface and underground, are subject to anthropogenic and
technogenic action, although with a different degree of inten
The main source of contamination of the water basin is
the discharge of sewage. According the state water inventory
in 2008 19 billion m
of contaminated were discharged into
water facilities, which is 36.2% of the total of drainage .
In housing enterprises there is about 80% of the total vol
ume of discharge of such contaminating substances as total
phosphorus (85.4%), ammonia nitrogen (83.4%), nitrates
(854.4%), and total nitrogen (77.4%) . A considerable vol
ume of contaminated sewage (insufficiently cleaned or alto
gether without cleaning) is discharged by enterprises of in
dustry, housing and agriculture .
In order to clean sewage there are predominantly works
with a biological cleaning system. Biological cleaning of
sewage is carried out in aeration tanks, which are structure of
concrete and ferroconcrete with a length up to 200, width up
to 10 and depth up to 6 m. In these structures with use of an
“active sludge” (bacteria) cleaning of sewage from harmful
impurities and organic contaminants is performed.
For effective operation of bacteria for cleaning sewage
constant saturation of the volume of water in an aeration tank
with oxygen is necessary (stopping is not permissible). Ac-
cording to data of the Scientific Research Institute of Munic-
ipal Services and Water Supply, up to 70% electrical energy
expended, which goes into cleaning sewage, is spent on
treatment in aeration tanks (more than 50 million kW/h of
electric power a day in the RF) . Therefore, a reduction in
energy consumption for cleaning works is an entirely appro
priate and important task. Comparative data for the energy
efficiency of different aeration systems are presented in Ta
ble 1 . Currently pneumatic aeration systems are acknowl
edged to be the most effective. The main method for accom
plishing this process is supply of air by compressors or air
blowers through aeration devices of a various types. An im
portant element in this system is the aerator nozzle for dis
persing air, which may be manufactured from porous poly
mer materials, ceramic or metal. The efficiency of aerator
nozzle operation for a gas is determined by the pore size and
air stream resistance. A reduction in pore size, and corre
spondingly the bubble size, leads to intensification of mass
transfer in the liquid – air system, which in turn increases the
degree of saturation of water with oxygen. A lower air stream
resistance makes it possible to reduce the requirement for
electrical energy in air blowers and compressors, pumping
this air to an aerator.
Refractories and Industrial Ceramics Vol. 51, No. 5, January, 2011
1083-4877/11/5105-0322 © 2011 Springer Science+Business Media, Inc.
ZAO NTTs Bakor, Shcherbinka, Moscow Region, Russia.