Week 11, 14th June

Yukhaimi, chemical technician explained the process of demineralization to me.

Firstly, service water is fed to the carbon filter. The influent water is passed through a column of activated carbon to remove the major part of the organic matter and residual chlorine.

Then, the water is routed to the cation exchanger packed with a column of strong acid cation, exchange ion resin in the hydrogen form.
The cation effluent is then passed through a strong base anion inside the anion exchanger. The hydrogen ions from the cation resin neutralized the hydroxide ions from the anion resins and yield pure water.

The demineralized water is then passed to the mixed bed exchanger which contain a mixture of anion exchanger and cation exchanger to further polish the water before the water is discharged to demineralized water storage tank.

Demineralization process for the plant

Week 10, 11st June

In the evening, there is a knowledge sharing session conduct by Amer (mechanical technician). He shared his experience about overhauling shutoff gas valve with us. This work will be done once a year during the outage session. Before installing the valve, they need to measure the valve can sustain how much pressure. The minimum pressure is about 25bar.

Week 10, 10th June

As the process of turbine start up includes torque converter, I had been asked to find out the function of torque converter.

The heart of Voiths’ hydrodynamic torque converter is its hydraulic circuit; consisting of a pump, turbine, and a guide wheel with adjustable guide vanes. This is combined in a common housing filled with hydraulic oil.

The mechanical energy of the motor is converted into hydraulic energy through the pump wheel. In the turbine wheel the same hydraulic energy is converted back into mechanical energy and transmitted to the gas turbine/generator shaft.

The adjustable vanes of the guide wheel regulate the mass flow in the circuit. At closed guide vanes (small mass flow) the power transmission is at its minimum. With the guide vanes completely open (large mass flow), the power transmission is at its maximum.

Basic design hydrodynamic torque converter

Week 10, 9thJune

Azlan (SBO) explained the trend of turbine speed during the start up. Before the turbine can be fired and brought to operating speed, it must first be rotated or cranked by an motor, operating through a torque converter to provide the cranking torque and speed required by the turbine startup. After the cranking speed reach 25% of the full speed, the turbine will start purging.

The process of purging stop when the turbine speed drops to 9% of the full speed. The function of purging is to drain out all the combustable gas from combustion compartment until exhaust compartment.

The process of firing starts after the purging until the turbine speed reach full speed.

Turbine speed trend

Week 10, 7th@8th June

As the plant having audit for integrated management system, the staff told us that we at least must know the mission and vision of the company.

Vision – The group envisions itself to be a global player in the energy and energy related business.
Mission – the group’s mission is to enhance shareholder return.

For the Quality Policy & Objective of the plant, the group is committed to be efficient and responsible by ensuring high standards in Quality and achieve full customer’s satisfaction by making ‘Quality A Way of Life’.

Quality Policy & Objective

Week 9, 4th June

In the morning, I followed Awang (BO) to the roof of the control room to make air-condition changeover. Air conditioner for control room was changed from 1B to 1A.

From Nooter Eriksen Operating manual, I learnt that recirculation pump on HP and LP economizers are use to increase the inlet feedwater temperature. It is required during the distillate oil as fuel. Condensation of acid can occur and corrodes the tubes of economizer if the temperature is low.

Week 9, 3rd June

I and another staff, Leo checked the temperature of the inlet and outlet drain valve at HRSG as there is suspected leak at the drain valve. If the inlet and outlet temperature is difference, that mean there is leakage at the valve. We use the infrared thermometer to measure the temperature.