In March 2019, Basamuk Refinery completed the second shutdown maintenance in HPAL T2 and Acid Plant T2.
A good start is half of the success. Before shutdown, the refinery management had organized several preparation meetings to confirm the maintenance plan, materials, equipment condition and personnel arrangements, so that guarantee the progress and quality of the maintenance.
It was planned to start from March 19th, however, the flange on HPAL train 2 medium flash vessel leaked accidently. For the stability and safety of the system, the refinery decided to start the shutdown maintenance 2 days earlier.
When cleaning the autoclave and discharge pipe, it was found that the scaling much less than before, it mainly because of the in-depth study of HPAL reaction and the optimization of the process and operation. The technical people analyzed the scaling in every shutdown maintenance, and found an effective way to slow down the scaling by adjusting process parameter and balance the reaction time and leaching rate, which prolonged the descaling period and improved the efficiency of HPAL plant.
During the shutdown, the refinery invited third parties to check and detect critical equipment like autoclave and Wirth pumps, and conducted the compliance audit for the pressure vessels, boilers and safety valves. The power plant cleaned the transformer in each area, and had some preventative electrical test for electrical devices like high voltage protectors and transformer protectors. All this detection and test helped the refinery to further eliminate the hazards and defects, and ensured the stable operation of equipment.
All other plant took this opportunity to check and eliminate hazards and defects in each area, and HPAL T1 and T3, and Neutralization & Product area had been kept high load with high daily input and product output, thus completed the monthly target.
With the thorough arrangement of the refinery and full support of each units, all people worked together to complete the tasks, and finally all projects were completed 54 hours earlier than plan, and the system was restarted with one shot, which provided strong support for production in future.
