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View Full Version : Can plain household bleach be used as a swimming pool sanitizer



stevenh496
08-24-2013, 09:17 AM
Hello,
This is my first post to this forum. Can household bleach containing NO additives be used as a sanitizer? Is sodium hypochlorite used in swimming pools manufactured identically to the weaker consumer bleach?

Thanks,
Steve

PoolDoc
08-24-2013, 01:41 PM
The short version: sodium hypochlorite is an effective source of chlorine for pools, whether from consumer bleach, or commercial (pool store) bleach.

Bleach is the consumer and commercial name for solutions of sodium hypochlorite, typically in concentrations from 3% to 8.25%. "Commercial bleach" is typically in concentrations from 10% to 18%. Pool stores, mostly in Florida, sell "commercial bleach" as "liquid chlorine", which is something of a misnomer -- true liquid chlorine, is the 100% chlorine gas, in liquid from, feed from the bottom of compressed chlorine gas cylinders.

Bleach is a desirable form of pool chlorination -- especially when you are not sure what to use. Cal hypo adds calcium; trichlor adds acid and stabilizer, dichlor adds stabilizer and some acid. If you NEED stabilizer and acid . . . trichlor may be your best choice. If you NEED calcium cal hypo may be your best choice. But what if you don't know how high your calcium is, or how high your stabilizer is? Then, bleach is your best choice!

Typically, the 8.25% Clorox bleach, and and the generic major store brand products, are PURER than "commercial bleach" or "liquid chlorine".

This is significant, because bleach deteriorates, changing from sodium hypochlorite (NaOCl) to salt + oxygen (NaCl + O2). The RATE at which this detorioration occurs is principally determined by 3 factors: temperature, concentration, and metal contaminants. Household bleach is typically filtered to remove metals; most commercial bleach is not. As the chart below shows, 8.5% filtered (store) bleach stored at 95 degrees is actually like to contain MORE chlorine, after a week, than 10% pool store bleach!

https://lh6.googleusercontent.com/-P-0ELYHAQuI/Uhjq4lzPt0I/AAAAAAAAGIo/zo40HO85DcM/s900/8.5vs10.jpg



Surprisingly, the chart below shows that even if you purchase 12.5% unfiltered pool store bleach, after just 18 or 19 days at 86F the 8.25% Walmart bleach contains more chlorine!

https://lh3.googleusercontent.com/-TzgaSvfnbQc/Uhju2-sjohI/AAAAAAAAGJE/LL30RC79RIk/s900/8.5%2520vs%252012.jpg


All the calculations for the charts were performed using Powell Fabrications "bleach decomp" program. Powell Fab (no relationship to me) makes bleach manufacturing plants, both with and without metal contaminant filtration systems. http://www.powellfab.com/technical_information/files/DecompHigh.zip

chem geek
08-24-2013, 03:39 PM
For what it's worth, both Odyssey Manufacturing (http://www.odysseymanufacturing.com/about_product.htm) and Hasa (http://www.hasapool.com/products/listing_detail.php?type=1071&id=5288) filter their water to minimize metals and have the chlorinating liquid last longer. I use Hasa and found its degradation rate to be very slow -- in line with the table at the bottom of the Odyssey Manufacturing link. Hasa talks a little bit about this history referring to Dwayne Powell in this link (http://www.hasapool.com/index.php?ID=3675&PID=3192).

PoolDoc
08-24-2013, 04:23 PM
Chem_Geek, do you know what label Odyessey product is sold under? From their site:

Ultrachlor is also available in drums and totes through Odyssey's re-sellers including the Dumont Company (www.dumontchemicals.com), Bell Chemical (www.bellchem.com), Florida Chemical (www.florida-chemical.com), SPIES (www.spiespool.com) and UNIVAR (www.univarusa.com) in the State of Florida.

Their site also notes:

The Odyssey bulk manufacturing process is unique. Chlor-alkali technology has been used for years to produce chlorine and caustic out of salt and water utilizing an electrolysis process. Odyssey takes this technology one step further by combining it with a Powell continuous bleach plant. Odyssey's process is superior in that it utilizes demineralized water and evaporated salt with membrane cell technology. The result is a much purer grade of caustic and chlorine relatively free from impurities. The resulting chlorine and caustic is taken directly off the cells and combined in a Powell continuous bleach plant to produce a superior quality product. Of the handful of companies who employ this technology around the country, Odyssey’s cell room has been in operation by far the longest.

So, it sounds like commercial bleach is much more often UNfiltered, than filtered.

Without a trustworthy brand label, I don't know of any way for the consumer to know what they're getting. I used to buy truckloads of bleach made by Allied Universal, who is a direct competitor for Univar. I was serviced out of their Ranger, GA plant. But I know that they had plants in Miami and other Florida locations, and did a LOT of pool store deliveries, with UN-filtered bleach. In fact, the way many of the Florida pool stores re-registrations were set up, they could fill their tanks with filtered bleach this week, and then purchase from Allied or another un-filtered producer next week.

chem geek
08-25-2013, 03:57 AM
I don't know the labels/brands that come from Odyssey, but Hasa sells direct to stores as the Hasa brand. Hasa has dealers on this map (http://www.hasapool.com/m_hasa.php?ID=3190) mostly in California, Washington and Arizona with some in Oregon, Nevada, Utah, Texas and Kansas. They have facilities (plants) shown in this map (http://www.hasapool.com/index.php?ID=3205&XID=3200:3205:0:0:0&PID=3200) in California, Washington, Arizona and Texas. It's filtered (http://www.hasapool.com/index.php?ID=3202&XID=3200:3202:0:0:0&PID=3200) sodium hypochlorite. You are right that there are many brands (such as Kem-Tek) and they are not manufacturers of chlorinating liquid themselves so it's hard to know the quality of their products. PPG has four facilities (http://www.ppg.com/chemicals/chloralkali/facilities/Pages/default.aspx) though they boast about volume and are silent about quality. This page (http://www.powellfab.com/products/chloralkali.aspx) has some interesting links from Powell on their chlor-alkali process.

stevenh496
08-26-2013, 08:55 AM
PoolDoc Ben,

Thank you for the response; you answered my question. Bleach seemed to be a quick and cost effective way to introduce chlorine prior to starting a new SWCG. The pool company gave several lame excuses why household bleach should not be used, but my opinion is that it cut into their profit margin.

Steve

PoolDoc
08-26-2013, 09:41 PM
Pool stores aren't all that enthusiastic about pool care methods that don't depend on their 'expertise' or products. The less honest among them generate all sorts of bogus reasons why bleach won't work, or why baking soda isn't the same as their alkalinity increaser.

robbym70
08-27-2013, 02:13 PM
The pool company gave several lame excuses why household bleach should not be used, but my opinion is that it cut into their profit margin.

Steve

Fast learner....I've heard some doozies myself from the pool store on using household bleach. One guy said it was poisonous, would harm swimmers and open me up to a lawsuit. I walked out of the store just laughing to myself and feeling a little sad for the people on the way in.

Thanks again to PoolDoc and company for getting me up and going three seasons ago.