Tuesday, February 22, 2011

drip filter

I convinced myself that purifying water at home is much cheaper than buying at the sari-sari store (that's the village version of the convenience store)... more convenient too, since I don't have to lug around a jug of water every few days. And so I ended up buying a drip filtration set (multi-stage filter) at the nearby mall.

It has a ceramic filter, which should remove the particulates from the tap water. Apparently, the pores in this filter are so small that even normal-sized bacteria couldn't get through! Then there's this cartridge with several layers: activated carbon, silica, and zeolite. Granular activated carbon and silica are said to trap the off-flavours and off-odours plus some more bacteria that are small enough to pass through the ceramic filter. Zeolite, on the other hand, acts like an ion-exchanger. Because of this behaviour, zeolite is used to attract heavy metals that are harmful to the body. Just before water gets ready to drink, it passes through a final stage where mineral stones are found. These stones are the nutrient-booster of the group since they "fortify" the water with important elements such as potassium and sodium. 

As I wait (impatiently) for the water to go into the lower tank, I remember my stay in Sydney Uni where I had to filter water as well... 

2006. My experiment was about measuring the particle size of starch polymers suspended in water. The machine I was using to take measurements was so sensitive that it could mistake dust (which tend to collect in water) as the target material. That was why I had to make sure that not even viruses could contaminate the distilled and purified water I was to use in my experiment. My water reservoir (distilled water) was way up above the bench; a long Tygon tube snaked its way from the reservoir to a collection bottle found on the floor. Atop this bottle was a filter that had pores smaller than the smallest viruses. Since the pores were really small, the filtration process was tediously slow: it took all day just to get enough dust-free water for sample preparation... I used so many filters because they kept getting clogged up by whatever was suspended in the water during filtration.

Back to 2011. Water flow is indeed faster in my home set up than in what I was using in school. However, it wasn't fast enough for me to stay up. I'm going to bed. Tomorrow, there should be enough water for taste-testing.