Reference is being made to the press release issued by Enemalta on the 5th of November 2012. Following the inspection and replacement of damaged parts at the manufacturer’s works and their subsequent shipment to Delimara Power Station, work immediately started on the reassembly. The steam turbine has now been fully reassembled and has successfully passed tests at both intermediate and full loads.
Following the assembly and as part of the re-commissioning, the following steps were taken:
Rotor alignment checks,
Balancing of the turbine rotor at rated speed, ensuring vibrations are within design limits,
Confirmation of the cleanliness of the steam system (steam blowing),
Minor adjustments to the control settings, such as the proportional and integral gains and time constants of its speed governor to eliminate possible ‘governor hunting’,
Testing of the turbine performance at both intermediate and full loads.
Such test procedures are standard during assembly of equipment, and in fact were carried out during the initial assembly of the steam turbine back in June 2012. Initial balancing is carried out at the factory but final balancing is always carried out on site following analysis of the actual vibrations.
Enemalta has requested a full analysis report from BWSC of the fault leading to the damage to the turbine, analysis of the broken rotor blade and the root cause of the failure of the strainer. BWSC have submitted a report which Enemalta considers to be of the nature of a pre-liminary report rather than the final report expected. As a result Enemalta will not allow the tests to continue, until such a report is submitted to the Corporation’s satisfaction. Once this report is received it will be critically reviewed together with the specialized external consultants engaged by the Corporation.
Only then will the plant will be allowed to go through the performance tests. These are the final testing procedures which, if found to be satisfactory, will lead to the taking over of the plant by Enemalta. The consultants, DNV KEMA, will also be assisting Enemalta in the review of the performance testing.
As stated beforehand, the reliability tests previously carried out were successful and there is no need for these to be carried out again.
As a result of Enemalta’s decision not to proceed with performance testing pending the satisfactory submission of a full analysis report from the contractor, BWSC have placed the plant in a state of “short term preservation”. This means that the fuel system in the engines has been flushed with gasoil, all silos have been emptied, and the plant has been put in a safe shut down state. Furthermore in order to avoid any inadvertent operation of the plant by Enemalta operators since the plant is no longer manned by BWSC supervisory personnel, the control screens and keyboards located in Enemalta’s control room have been temporarily disabled. The computers, which control the plant are fully functional and have not been switched off. This is exactly the same action which was taken by BWSC when testing was last postponed following the damage to the steam turbine, and is a normal procedure intended to protect the plant prior to its handing over to Enemalta.
As stated last October, Enemalta has reached an agreement with BWSC to replace the dump condenser with a newly improved design at their cost.
Contrary to what has been alleged in the media the flue gas abatement system is working properly and in fact abatement levels are better than those stipulated in the contract. During the latest unloading of waste from the silo to the container, there was a small leakage caused by a damaged bellow on the unloading nozzle and a hatch cover on the container, which was inadvertently not closed by the operator. The operators are provided with suitable protective equipment to cater for this kind of eventuality. The damaged bellow will be replaced by BWSC at their cost.
Enemalta reiterates its position that it will be taking over the Delimara extension only after the root cause of the failure of the strainer has been identified and addressed to its satisfaction and the satisfactory completion of the performance testing. In the meantime Enemalta is applying all the contractual remedies to the situation.
- Steam turbine report reviewed and accepted
by MaltaMedia News -10 December 2012
- Power station should be handed over to Enemalta soon
by MaltaMedia News -4 December 2012
- Enemalta takes over Delimara Power Station extension
by MaltaMedia News -14 December 2012
- Enemalta explains power cut in statement
by MaltaMedia News -3 April 2010
- Study confirms power station meets air quality standards
by MaltaMedia News -1 September 2011