Jim,
I do not agree with your claim that the old methods are ineffective. First, I think you will agree with me that those old non- corrosive methods (i. e. polyphosphate) can remove and prevent scale formation in most of the drinking water very well and inexpensively. Some of those problem waters will need special care which can cost more. This does not mean that polyphosphate is ineffective. Each water supply has its own unique chemistry, therefore, they may need a special dosage and formulation to achieve the best effect. Not all of the water suppliers has the same level of treatment technology. Therefore, some of the technologies may not work well as promised. But, that can be improved most of the time.
Please do not mix drinking water with industrial water treatment. They are very different. The chemical formulations use to treat Navy's vacuum drains is very very different from that used to address the sprinkler MIC problem at that particular location. I have never seen any sprinkler problem, because of I have monthly sprinkler flushing schedule in my lab in the last 15 years. What you mentioned scale and bacteria problem in sprinkler system really troubled me, because of there is no water flow during the stagnation period. Whatever in the water is in such minute amount which can not possibly cause those problems. Where are the minerals and nutrients come from to form scale and bacteria problem in the sprinkler systems? You must be talking about a very unique water problem. You need to be very specific if you want to disagree on a very specific issue.
I can see the main ingredient in HERC's formulation is EDTA(very old chemistry but effective) which is usually used at non corrosive pH conditions. It is an very old technology too. Slightly, corrosive chemicals still can be used if the treatment time is not too long and the residual chemicals are flushed and neutralized after the cleaning. It is an acceptable method for treating very difficult scale problems. Non-corrosive method is not equal to an economical nor practical methods if it does not do a faster and better job when time and money are important factors. We can find many non-corrosive formulations right from the old NACE's journals. I know many of them, and plus I have several years of formulation experience of these chemicals. This is the field I feel that I qualify to make some comments. I will be very surprised to find that HERC has an outstanding invention. You brought up my interest, I have to read the patent(S). If they really have a good invention, I will be very happy to say so at here.
Sincerely,
Wade |
