Oddly enough, there's a link from the page that Joe references that takes you to a marketing site for one of the "total solution" treatment products - but, in this case, the active ingredients and MSDS and laid out plainly......and Lye is prominent on the list. An amine is also present.

So, Lye.........how does this ancient and somewhat unpleasant chemical compare to the more modern alkalis?

dave

Greetings:
This has been a most informative and useful thread.
A couple of comments.
First, DEHA (Diethylhydroxyamine) is not propritary, it is mixed up and sold by many firms. Everything in DEHA can be found on the MSDS sheets.
Second,Valley Railroad has been using it consistantly for about a year and a half. We have used it off and on to address specific issues since 1990, but since last year it has beed the only oxygen scavenger used. We continue to use a polymer to control scale formation and a little caustic (lye) on an as needed basis to keep the Ph in range.
Based on our annual internal boiler inspections last January (which revealed no oxygen pitting, etc.) we decided to use DEHA exculsively this season. We'll know next January just how well it is doing.
We were using Sodium Sulfite with good results (read: no oxygen pitting), but found that we had to blowdown quite bit to control the TDS especially during our winter schedule when we use a lot of steam just to heat the train.
One of the advantages of using DEHA is that we use very little (usually 1 or 2 ounces) per day, so we have greatly reduced the number of blowdowns needed per month.
Happy steaming!
J.David

J. David,
Nice to know that there is someone out there who agrees with me in philosophy and practice. This is my ' like ' button ;-).

I'm sure you take safe handling precautions and use proper Personal Protective Equipment when handling Caustic Sodium Hydroxide ( Lye ).

One of the selling points of Anodamine and Terlyn is that they contain no caustic or Immediately Dangerous on Contact chemical ingredients. As previously described, Phosphonates are organically bound forms. They change under boiler conditions, with the phosphorous separating from the organic portion. In concentrated form, they are weak acids, with a pH of about 6, close to neutral.

The recommended dose rates of the above products are two ounces per 1,000 gallons of softened water, where the boiler is clean and the intent is to simply maintain and protect. Where some remedial cleanup is necessary, or the water is hard, the recommended dose is simply doubled. To get a freshly filled boiler off to a good start, experience has shown that X 10 on the initial fill dose gives good results. We are talking $ 1.25 per ounce at small package ( quarts and single gallons ) retail. Many of the steam traction, boats, autos, live steam modelers and park trains are using these sizes and having excellent results. For larger package sizes, available from Anodamine, Terlyn, BoilerSaver or Iron Horse and possibly others, it is a competitive marketplace.

To illustrate a simple nitrogen blanket setup, attached are some photos of a 24 inch Crown. Being small, the boiler connections show on one photo. The tank has a first stage regulator down to about 20 PSI. The second stage regulator is an off-the-shelf propane regulator, factory set at 11 inches of water ( about 0.4 PSI ).

The connection is by a flexible air tool hose. The quick connection from the hose to the 1/4" check valve is a brass air tool connector. It won't rust. The " O " ring has been coated with silicone grease for protection. The nipples are schedule 80 and the valves are 300 WSP. The connection can be made anywhere above the water line, into a line that is not flooded.

An important detail is to have the connection to the check valve running downslope toward the boiler. If ( when ) condensation gets past the check valve, we do not want it forming a liquid trap in the supply line. This trap can prevent nitrogen flow. Let the condensation flow back towards the boiler. An experience-based improvement learned since these photos were taken is to use a Stainless Steel or hard copper tube condenser coil just prior to the quick connection. This cools any condensation quickly before it can back up the flex hose.

Nitrogen blanketing should be utilized only after a boiler has been steamed and vented, dissolved oxygen driven off.

The nitrogen should be applied when there is some low steam pressure present. Simply open the supply, verify pressures, make the quick connection and open the manual valve on the boiler top. The check valve will ( should ) prevent reverse flow. When the steam cools and the boiler starts to go into vacuum, the nitrogen pressure opens the check valve and nitrogen starts flowing. The nitrogen supply should be maintained until the boiler cools to 110 F. After that, the nitrogen supply can be shut. Standard procedures in industry include a 15 minute purge of the boiler weekly. Simply turn on the nitrogen supply for a while. I have often seen this automated with a timer and solenoid valve.

Proper safety practices include placing a sign at manholes marking the Confined Space and Inert Atmosphere. Check air quality prior to entry .

Full Coaches and Happy Steaming !

Here are my 2 eurocents:

The comment of the user:
This is a picture of a firetube of locomotive SHM 5. (Hoorn - the Netherlands)
The tube has been used from 1991 to 2012. The locomotive was used intensively during that period and sometimes remained pressurised for weeks. One can see the clear advantage of a good water treatment. Water softening is by ion exchange, then desalination by reverse osmosis and blowing-off to prevent the water to become too salty .
100 ml / m³ DM 4:1 is added, which is tannin based that binds the oxygen. This is to counteract corrosion especially on the tubes. It also forms a skin with iron ions, which shields the steel surface from corrosive ions. Furthermore, Alkatreat is added that contains sodium hydroxide. Adding to the neutral water makes it alkaline with a pH of about 11 .
As a consequence they never have to wash boilers. Once a year the boilers are opened and cleaned with a vacuum cleaner. They also have never suffered from boiling up/water to the cylinders.
If the locomotive is not used more than 4 days, the boiler is blow-off warm and dried with electric heating in the firebox, the boiler is ventilated at the same time.
None of the fire tubes of locomotive 5 was leaking .
This method of boiler treatment is a must for any steam locomotive owner who wants a long life expectancy for his boiler and hates the time-consuming boiler washing. Cold days are never necessary.

Kind regards
Jos Koopmans

I have an involvement with LMS 8F 8624 based at the Great Central Railway, England. That railway uses reverse osmosis plus water treatment, which I believe is also tannin/caustic soda based. 8624 has steamed over 50 days between washouts and with similar results to those reported above. The inside of the boiler is very clean; we recently had to change one tube for a pinhole leak which looked like spot corrosion at a seam welding flaw and the rest of the tube was clean black steel, 4 years into the current boiler ticket.

Tim

060 Hogger- if you don't want to fire up the boiler before applying the nitrogen blanket, you can also use nitrogen to "sparge" the oxygen from the boiler water. This is done by bubbling the nitrogen up through the water; this drives off the dissolved oxygen and replaces it with relatively inert nitrogen. I would think you could get adequate distribution of the nitrogen by connecting it to the blowdown connections on the boiler. You'd have to vent the high point (hold the whistle open?) and run it at a high enough flow rate to agitate the boiler water, and long enough to remove the disolved oxygen. Depending on the size of the boiler, this might require a prohibitive amount of nitrogen, but nitrogen is pretty cheap.

I've seen this process used to remove the oxygen from feedwater for nuclear applications.

Deleted due to double posting.

I'm happy to know what's working well in various places...but doesn't your recipe need to be based on the particulars of your feedwater? If my feedwater has very different characteristics than that in the places we're hearing from, without knowing how it is different or the methodology of why and how those particular treatment strategies and products were chosen.....it isn't really meaningful information. Or is it?

I think I'm sort of hung up on proportion, and on not wanting to overtreat with more of anything that is required to achieve good internal chemistry.

dave

How often should one operator test their water source?

Also, does anyone use a commercial-grade or industrial grade water softener for their water supply?

You learn how often to test based on experience. Once you start your test program, you test frequently so you learn how the quality of your feedwater changes over time. In my experience, water changed slowly from spring fresh snowmelt through the summer, when it was sort of heavier runoff. If you find the test results vary very little between daily tests, you could try weekly tests......if they vary widely and frequently you need to test very often, and your strategy is reactive more than proactive. You want to test the water coming from your source, the water coming into the tender, and the water from the blowdown.

dave