Aeration equipment for waste water treatment plants
Celpox bioreactors
Efficient heat transfer from sludge treatment plant
ox heat exchanger

Company: CELPATEKNIK AB (Sweden)

Bioreactor Celpox  is an innovative device for transferring air into sludge in waste water treatment plants. Due to high energy density and strong turbulence in the reactor tube, the oxygen transfer efficiency is very high and the sludge organisms absorb the organic matter quickly. Efficient oxygen transfer is obtained at a rather low energy cost.

1910 Rockhammar 2 114 Celpox 1273 Kõrgessaare 12

Celpox bioreactors can be installed in all tanks regardless of their size or shape, whether they already exist or are being planned.

Celpox  bioreactor’s efficiency is easy to adjust by regulating the oxygen indicator according to the oxygen consumption of the sludge, which enables to save energy during low waste production periods (only one of two circulation pumps is operating).

Celpox  bioreactor is easy to maintain and is completely mechanical with the only moving parts being the two thrust pumps with low rotation frequency. All connections that need maintenance are located above water surface. This means that there is no need to empty the tank for bioreactor maintenance or repair.

Celpox  bioreactors are produced in several
sizes and can be equipped with additional devices.

Celpox  bioreactor can be equipped with a heat exchanger to use the heat from treated waste water in a simple and efficient way.

It is also possible to equip Celpox  with a device to efficiently dose phosphorus deposition chemicals into the tank.

With Celpox  it is possible to dissolve any gas in waste water.

It is also possible to adjust Celpox  to dissolve pure oxygen into waste water.

Celpox is a device that can be used for treating different types of waste water in tanks with varying shapes and sizes.

Celpox can be attached to floats.

Celpox can be manufactured considering the specifics and special requirements of the waste water treatment plant.

Celpox is a highly versatile and flexible device which is suitable for any type of sludge treatment plant.

1910 Rockhammar (Rootsi)

  Celpox 955 Celpox 1273 Celpox 1910
Reactor tube diameter mm: 955 1,273 1,910
Water depth H1 m: 2.5–12 2.5–12 2.5–12
Device height from the water H2 mm: 1,900 2,100 2,100
Maximum tank capacity per one Celpox (m2) ~250 (50) ~750 (150) ~1,200 (280)
Mass (H1=4 m) kg: ~900 ~1,400 ~2,500
Materials: SS 1311-2343 SS 1311-2343 SS 1311-2343
Engine power N kw: 4.0 7.5 15.0
Standard oxygen transfer rate (SOTR) kgO2/h 25 45 90
Production and sales

AS J.I.T. is licensed by Celpateknik AB to produce and market Celpox bioreactors. The bioreactors are made from stainless steel in adherence to designs by Celpateknik ABE. Equipment sales are project-based. Delivery, installation, and adjustment are included in the price of the bioreactor.

Choosing a suitable bioreactor

The specialists at AS J.I.T. or Celpateknik AB select the suitable bioreactor(s) considering the properties of the waste water and the shape and size of the tank. AS J.I.T. is ready to offer complete solutions for biological treatment of waste water along with the necessary equipment.

Renting a bioreactor

AS J.I.T. offers Celpox bioreactors for rent to restore or increase the aeration capacity of sludge treatment plants. Average rent term is 0.5–1.5 years.

Spare parts

We supply original spare parts for the bioreactors.

After-sales service of bioreactors

Qualified specialists at AS J.I.T. offer the following services:

  • Post-tuning of bioreactors and technological adjustment of the sludge treatment process
  • Schedule-based technological maintenance of bioreactors (subject to agreement)
  • Repairs, adjustments, and upgrading of bioreactors.
Guides for Celpox bioreactor users
pdf Celpox 955 maintenance guide pdf Celpox 1273 maintenance guide pdf Work safety rules for Celpox device user
Celpox heat exchange system

Celpox heat exchange system is created for efficient separation of heat energy from the waste water treatment device to produce warm water and heating for plant rooms.

Working principle

A spirit or glycol solution (heat exchanger solution) circulates through the heat exchanger cell surrounding the reactor tube of the Celpox bioreactor.
The heat in the sludge treatment plant is transferred to the circulating cooling liquid both through the inner and outer wall of the reactor tube. The strong turbulence processes in and outside the Celpox bioreactor’s reactor tube ensure maximum heat transfer to the cooling liquid. Transportation of obtained heat for further use is done with industrially manufactured heat pump devices.


Heating centre at
Vändra waste water treatment plant


Heating centre at
Aseri waste water treatment plant


Heating centre at Kaarlijärve (Estover Juustutööstus, Tartu County)
waste water treatment plant



The reactor tube of the Celpox bioreactor is equipped with a double cell which contains a spiral metal belt, creating a long channel around the reactor tube for the heat exchanger liquid flow. The low temperature cooling liquid is directed into the heat exchanger from near the container’s bottom, continuing spirally upwards. Discharge is conducted at the top part of the reactor tube near the water surface.
Long-term experience shows that thanks to intensive movement in the sludge contact zone, there is absolutely no covering of the transfer surface (which would hinder the heat transfer). The latter is the most common problem with using heat exchangers in regular aeration systems.

Heat transfer

The outcome of heat energy at cooling liquid speed of 240 l/min is:

Water temperature in the sludge treatment plant 4–7 ºC

Celpox 955        60 kW

Celpox 1273      90 kW

Water temperature in the sludge treatment plant 15 ºC

Celpox 955        105 kW

Celpox 1273      135 kW image023  

Installed Celpox heat exchangers

Alfta waste water treatment plant (WWTP) (Sweden) 1 Celpox 1273
Munnkfors WWTP (Sweden) 2 Celpox 955
Aseri WWTP (Estonia) 2 Celpox 955
Vändra WWTP (Estonia) 1 Celpox 955
Kaarlijärve WWTP (Tartu County, Estonia)   1 Celpox 1273


pdf Heat exchanger Celpox