Gas Chlorinator Vs. Bleach

Gas Chlorination

• Gas chlorinators are machines that mix chlorine gas with water to make a chlorinated solution and inject the solution into a water supply. When working with a gas chlorinator, you'll typically need to purchase liquefied chlorine stored in high-pressure containers; these vary in size from 100 lbs. to a ton or even more. Always keep cylinders on platform scales placed on a solid, flat surface and make sure the area is well ventilated. The piping for the chlorine solution should be made from corrosion-resistant material, and all pipes for the chlorine gas should be able to tolerate high pressure.

Sodium Hypochlorite

• Adding sodium or calcium hypochlorite to a water supply is another approach to water chlorination. Don't use bleach to chlorinate a pool -- bleach is a more diluted solution, so you'll need to add more to get the same effect, and the bleach may contain other additives, especially if it's scented. You can buy calcium and sodium hypochorite intended specifically for pool chlorination. Bleach is a better choice for shock-chlorinating wells to disinfect them. You can also use bleach in conjunction with hypochlorinator systems, which are machines that inject solutions of hypochlorite salts into the water supply at a steady rate.

Hazards

• The bleach you buy at the supermarket has an excess of sodium hydroxide, so it's a very alkaline, or basic, solution. Consequently, it's liable to coat the valves in hypochlorinators with calcium carbonate. On the other hand, it will not form insoluble precipitates when combined with sodium fluoride, an additive in the water supply in many locations. Although bleach can be hazardous if misused, in general it's much less hazardous than gas chlorinators, because these can potentially leak highly toxic chlorine gas. Anyone working with a gas chlorinator should have chlorine safety training and a self-contained breathing apparatus should be on hand.

Considerations

• Despite the safety hazards they pose, gas chlorinators are more effective in cases where you need a variable flow rate. Gas chlorinators cost more to purchase and install, but you can often obtain the necessary chemicals more cheaply if you are working on a large scale -- chlorinating a municipal water supply, for example. Hypochlorinators are cheaper to purchase and easier to maintain, especially when you are working on a smaller scale.