* – in order to obtain the best result of turbine oil regeneration, it is recommended to first remove mechanical impurities by means of CMM-4.0F unit and water — by means of CMM-1.0CF unit.

Turbine oils are used for lubrication and cooling of bearings in various turbogenerator sets of steam and gas turbines, hydraulic turbines, and turbocompressor machines.

The main problem in usage of turbine oils is the need to ensure the stability of physical and chemical properties over a long period. It is not easy to do because of difficult operating conditions of oil which are characterized by high local temperatures, exposure to atmospheric oxygen, contamination with mechanical impurities, etc. The mentioned factors disrupt the operational properties of oil. Statistically, up to 20–25% of failures, defects, and damages of power turbines are due to the causes associated one way or the other with degraded quality and deteriorated properties of turbine oil.

Purification of turbine oil

Accordingly, turbine oils should be purified both before feeding into the oil system of power turbines and periodically during operation. For that purpose, different principles are used and implemented in mechanical filters, separators, centrifuges, electrostatic purifiers, and vacuum dryers. However, this kind of equipment is most often aimed at removal of mechanical impurities and water; however, it doesn’t manage to remove aging products (acid compounds, etc.).

Aged turbine oil is not capable of performing its functions, and its usage may lead to breakdowns of power turbines followed by lengthy and costly repairs. Now, aged turbine oil is changed for new oil in most cases, although used oil contains useful hydrocarbons and can be reclaimed for reuse according to its intended purpose if the right approach is applied.

Regeneration of turbine oils in CMM-6RL unit

CMM-6RL unit has proved its worth in reclaiming the properties of used turbine oils at nuclear and thermal power plants. It takes a different approach to oil processing in comparison with filtration, separation, centrifugation, electrostatic purification, and vacuum drying.

GlobeCore principle of turbine oil regeneration is based on pumping the turbine oil through the columns preliminarily filled with a special natural adsorbent (one column contains about 150 kilograms of adsorbent). The adsorbent absorbs all the oil aging products and subsequently retains them in its granules. The oil that has passed through CMM-6RL unit becomes purified, clarified and completely regains its operational properties; therefore, it can be reused in the oil systems of power turbines.

Operation features of CMM-6RL unit for regeneration of turbine oil

The main feature of CMM-6RL unit is the possibility to reactivate the adsorbent without removing it from the regeneration columns. If the used adsorbent should be disposed of in other equipment of a similar intended purpose, GlobeCore technology ensures reclamation of the adsorbent by burning, as well as repeated use thereof for regeneration of turbine oil (at least 300 reactivations).

1. Duration of operating cycles and power consumption
2. CMM-6RL unit for regeneration of turbine oils sequentially operates in the following modes:

• Oil regeneration (duration — 6 h, power consumption — 1.5 kW/h);
• Adsorbent reactivation:
• preparation (duration — 1 h, power consumption — 6.25 kW/h);
• adsorbent ignition (duration — 1 h, power consumption — 17.5 kW/h);
• adsorbent combustion (duration — 15 h, power consumption — 25.5 kW/h);
• refilling (duration — 0.5 h, power consumption — 6.5 kW/h)

Advantages

• Convenience of operation. The unit is quickly connected to tanks for clean and dirty oil through camlock quick couplings; the oil purification process is visually monitored by means of sight glasses; a service hatch is provided at the bottom of the columns for their maintenance and cleaning.
• The unit can operate in automatic mode. The required operating mode is selected, and the actuators are controlled from the touch panel which displays a mnemonic diagram of the unit. In order to enable the control buttons, the operator just needs to touch them.
• The adsorbent is reclaimed without being removed from the unit and can be used for the next regeneration cycle immediately after cooling. At the end of the last reactivation, the adsorbent can be used as a construction aggregate or in agriculture to loosen compact soils.
• There occur no harmful emissions into the environment during the unit operation. The unit is equipped with a two-stage system for neutralization of combustion products which consists of a carbon filter and a catalytic converter.