QJB Submersible Mixer

QJB Submersible Mixer

The QJB submersible mixer is available in two series: mixing agitation and low-speed flow propulsion.

Mixing series: suitable for agitating liquids containing suspended solids in wastewater treatment plants and industrial processes.

Low-speed flow series: suitable for aeration tanks in industrial and municipal wastewater treatment plants. It generates a powerful low-tangential flow that can be used for circulation and for creating water flow in the nitrification, denitrification and phosphorus-removal stages.

Note: the mixer must operate fully submerged. It must not be used in explosive atmospheres or with strongly corrosive liquids.

Model designation

QJB

Main features

1. Compact structure, simple operation and maintenance, convenient installation and servicing, long service life.

2. Hydraulically designed impeller delivers high working efficiency; the backward-swept blades are self-cleaning and resist wrapping and clogging by debris.

3. When used together with an aeration system, energy consumption is greatly reduced, oxygen transfer is noticeably increased, and sedimentation is effectively prevented.

4. Motor winding insulation class F, protection class IP68, with quality bearings for safer motor operation.

5. Double mechanical seal.

Operating conditions

The mixer should run continuously and normally under the following conditions:

1. Medium temperature not exceeding 40°C;

2. Medium pH value between 5 and 9;

3. Liquid density not exceeding 1150 kg/m³;

4. Continuous submerged operation, with submersion depth generally not exceeding 20 m.

Installation notes

1. The dedicated installation system allows the mixer to be installed and removed quickly without draining the tank.

2. Installation system I applies only to tank depth < 4 m and to models QJB0.85/8-260/3-740C and QJB1.5/6-260/3-980C; type I-1 can be adjusted both horizontally and vertically.

3. Installation systems II, III, IV and VI apply to tank depth ≥ 4 m; the guide rod can rotate about its own axis in the horizontal direction, with a maximum rotation of -60° to +60°.

4. When tank depth exceeds 4 m, an additional support bracket shall be added in the middle of the guide rod.

5. The support bracket and lower bracket are fixed to the tank wall and floor with steel expansion bolts; no pre-formed holes are required.

6. Please provide the tank depth and tank drawing when ordering, so that guide rod dimensions and the number of support brackets can be determined.

7. Installation system material: stainless steel or anti-corrosion treated carbon steel, as selected.

8. Multiple mixers can share one lifting system.

Selection notes

1. Application

2. Tank type and dimensions

3. Medium characteristics: viscosity, density, solids content

Selecting a submersible mixer is a relatively complex task; correct selection directly affects normal use of the equipment. The guiding principle is to let the mixer deliver its full mixing function within a suitable volume, which is generally determined by flow velocity. Depending on the process requirements of the wastewater treatment plant, the mixer flow velocity should be maintained between 0.15 and 0.3 m/s. Below 0.15 m/s the flow-propulsion and mixing effect is not achieved; above 0.3 m/s the process result is affected and energy is wasted. Therefore, before selection, first determine where the mixer will be used – for example a sewage tank, sludge tank or biochemical tank; then the medium parameters such as suspended solids content, viscosity, temperature and pH value; and also the tank shape and water depth. The required motor power is determined by the tank volume, the density of the mixed liquid and the mixing depth, and one or more mixers are used according to the specific conditions.

Technical data