The entire week have been an interesting. Besides my routine job, I learned and experienced new things. However, I will share only the following 3 stuffs.
Vacuum dropped due to wet steamI hate this case!!! When vacuum pressure dropped, the quality of oil is affected and most of the time the oil have to be rejected. In this case, vacuum dropped occurred because of wet steam. Wet steam is basically water carry over from boiler. Boiler is supposed to produce steam and deliver it to plant. When boiler began sending steam + water to the plant (which is not suppose to happen), the vacuum system is interrupted. The vacuum lost its capability to suck fatty acid which is supposed to be removed from the oil. I could not let it happen again. I don't want my plant to reject oil again because of this 'typical' reason. The boiler people never want to admit that they sent steam + water to the plant.
Therefore, I decided to investigate the case further. Few minutes after the 3rd incident ocurred (wet steam) I took a bottle of condensate water sample (this is the condensed steam which became hot water) and tested its TDS (total dissolved solid). We tested the TDS using a digital TDS meter at the boiler house. The TDS of the sample showed 70 ppm. Normal condensate water should display reading less than 10 ppm. This implied that water carry over (wet steam) happened. Why? Because, steam is water (H2O) at 120 ++oC temperature (around 15-17 bar). Hence the boiler is/should only send steam (pure H2O). Pure H2O should have zero or very minimum content of metal/solids/substance inside it. When steam condensed and became condensate water, the content of metal/solids/substance should remain. However, when wet steam occurs (due to water level fluctuation inside the boiler), some water follows the steam to the plant. The water is chemically treated and this increased its TDS. Therefore, if the condensed water is 'rich' of TDS, this confirms that wet steam is taking place.
Up to today, I gathered 2 condensate water samples (as proof) after the wet steam incident and the TDS result is very high!!! The boiler people definitely have to do something to avoid this from worsening or happening again. I'm not accusing anybody to be responsible of the "oil rejection". I sincerely just want to solve the problem. Save cost and time as well.
Checking the Total Dissolved Solid (TDS) at different temperatureWhen I first checked the condensate water sample which was collected by my supervisor, it showed TDS of 67 ppm. The boilerman said, that is impossible. He claimed that my sample was very cold (I left the sample in my office for about 5 hours before testing it. Therefore the air condition has cooled down the condensate water temperature to about 24-27oC). That's fine....I told him, let's heat the same sample up to 65-70oC and repeat the TDS test. We heated up the sample and re-tested the sample at 65oC. The sample showed reading around 70ppm. At least, it's close the the earlier TDS reading. Before repeating the TDS test, I told the boilerman that TDS have nothing to do with temperature. However, he stubbornly claimed that temperature influenced the TDS reading. After that he kept quiet and admitted that temperature have nothing to do with TDS. Hence, the condensate water really have high TDS which means water carry over (wet steam).
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