Most Frequently Replaced Parts for Your Sodium Hypochlorite Generator



When you’re prioritizing maintenance for your vessel or offshore production platform, it’s important to know the reasoning behind your investment. Taking the time to understand what each machine on your vessel does can help clarify why maintenance and replacement parts are crucial for your safety and quality of life while at sea.

One such machine is your vessel’s sodium hypochlorite generator. From time to time, you’ll need to invest time and money into ensuring that this generator is working the way it should. Why is this important? What does your sodium hypochlorite generator do, anyway? What will happen if you don’t care for it as you should? 

We’ll discuss these questions and more in this blog:

What is a sodium hypochlorite generator? What does it do for your vessel? 

Your sodium hypochlorite generator works as one of the water treatment systems on your platform or vessel. When you’re on a platform offshore, you have to have a firewater and cooling water influx supporting your systems. You have to use seawater as the source for these lines. Before that seawater can be used, it needs to be cleaned and clarified. That’s where your sodium hypochlorite generator comes in handy. 

A sodium hypochlorite generator is a system that is designed to treat incoming seawater with generated amounts of bleach. This machine can also help remove microorganisms and other sea growth from incoming seawater lines. 

For example, if the seawater that you have coming into your system is full of barnacles and slime, a little bit of bleach will kill all of that marine growth. The resulting purity and clarity of your incoming seawater will help your other systems run properly. 

Just like the other complex treatment systems on your production platform or vessel, a sodium hypochlorite generator is only going to work well if it’s regularly maintained. This will require regular cleaning, as well as occasional inspection and replacement of any parts that may have experienced wear and tear. Why is this maintenance so important? What’s the real risk at hand if you aren’t able to focus on inspecting your sodium hypochlorite generator regularly? In the next section, we’ll look at precisely what happens when your generator goes too long between regular cleanings. 

What happens when your sodium hypochlorite generator isn’t taken care of? 

If parts of your sodium hypochlorite generator begin to break down or experience too much wear, the whole generator system will fail to work well. This can produce low quality and unclean water for the rest of your systems that depend on treated seawater—which can result in the poor performance or failure of many different systems. 

If your sodium hypochlorite generator does not work, your incoming seawater line will be full of barnacles, mussels, and other marine grime. As a result, these lines of water won’t flow properly. If this is the case, you won’t be able to run your firewater line, which can result in unsafe situations for your platform and your crew. You also won’t be able to run a line of cooling water, which helps keep your systems safe and operating efficiently. 

Aside from safety concerns, there are large financial investments to protect. If you end up having to replace your entire sodium hypochlorite generator system due to a lack of regular maintenance, it can cost over $1 million. 

What are some maintenance rules of thumb for your sodium hypochlorite generator?

Very simply put, your sodium hypochlorite generator needs to be cleaned “as needed.” The key factor is to understand what that needed rate may be. This will require that you become more familiar with your generator and the conditions it’s working through. 

You may have heard that a good rule of thumb is to acid clean the electrolytic cells in your sodium hypochlorite generator approximately once a month. However, that advice is outdated and inaccurate—we know much more about proper maintenance now! 

For a more updated, reliable process, consider the following: When you get a brand new sodium hypochlorite generator, set it up and run it for one week. After that week, pull out an electrolytic cell, and examine how clean it is. (Taking a picture will provide a good reference point.) Put the cell back in, and turn the machine back on. 

Do this every week for three weeks, paying attention to when the electrolytic cell gets dirtier, and you’ll get an idea of when you should be cleaning it. It would be a good idea to clean it once every 1-3 weeks, at least. It’s definitely a good idea not to go over four weeks without giving it a good cleaning. 

How to clean a sodium hypochlorite generator

When you’ve determined that your generator’s electrolytic cells are in need of a rinse, here’s a quick process that can help you do just that: 

    1. Shut down your unit. This may be as simple as pushing a button to initiate the shutdown sequence for your generator. Your generator will stop making bleach, perform one last rinse of seawater, and then close the system’s automatic valves.
    2. Open drain valves to drain the system. This will allow the access you need to give your system a thorough cleaning.

    3. Take apart the system, clean off any grime, and reassemble. Disconnect the bolts, disconnect the flanges, and pull internal outs to clean. Then, put the system back together. 

    4. Acid Clean the System. Shut down the system, align the valves for acid cleaning, Acid clean for one hour. Set valves to reclaim the acid, flush system with clean seawater, open drain valves, take system apart and inspect

How much time this will take depends entirely on how complex your sodium hypochlorite generator system is. The more electrochlorination cells your generator has, the more time it will take to clean. It may take a dedicated mechanic 1-2 days of full-time labor to clean it out fully. However, It can take much longer, like 3-5 days, if you’re doing other maintenance at the same time and have a more complicated system. 

What are the most frequently replaced parts of your sodium hypochlorite generator? 

When you’re cleaning your system and notice that a part is completely worn through, you may need to replace it. You may be wondering which parts of your sodium hypochlorite generator will need replacing most often. In many cases, the different parts of your generator won’t need replacing until your entire generator system requires an update. 

For those times when part replacement is necessary, keep an eye on these top five pieces: 

    1. Fasteners and hardware for the electrolytic cells: Your sodium hypochlorite generator will have thousands of nuts and bolts already on the equipment. Most of this hardware will be very common pieces, readily available at most hardware suppliers. However, in addition to this regular hardware, the nuts and bolts on the electrolytic cells must be made of titanium. It’s best to get this hardware directly from the manufacturer. If your sodium hypochlorite generator is from H2O, you must get the electrolytic cell hardware from H2O as well. 

    2. Electrolytic cell housing: The casing or housing for the electrolytic cells shouldn’t break for about twenty years. However, they are made of plastic, and they will break if they’re thrown or experience any undue force. It’s a good idea to check them for cracks or dents in the plastic. 

    3. Replacement electrolytic cells: Your electrolytic cells provide invaluable function for your sodium hypochlorite generator, so it’s a good idea to make sure these are running optimally as well. To determine whether they need to be replaced, monitor the voltage across these cells with a multimeter. By the time the voltage across these cells hits 35 volts, they will likely be worn out and in need of a replacement. 

    4. Parts for the electrolytic cells (e.g., valves and actuators): These valves and actuators are automatic pieces that open and close, changing the stream of the flow. These are automatic parts that can wear out over time. The level controllers are related; these specific pieces keep a level flow rate in the tank so the unit can continue to run. When the generator system gets backed up or otherwise doesn’t seem to be flowing appropriately, it’s time to take a look at these pieces.
    5. Transformer rectifier unit: A transformer rectifier unit is a two-part unit which includes an interface and a firing card. Your system’s transformer rectifier unit ultimately takes AC current and turns it into DC current. If these parts fail, you won’t be able to get the voltage you need in order to safely and effectively power your electrolytic cells. If your system isn’t getting the voltage it needs, you may want to take a look at the transformer rectifier unit. 

The main issue with sodium hypochlorite generator maintenance is simply that it’s not very high on the maintenance list! It doesn’t directly make oil, so it’s often not seen as a priority. This can lead to a lack of assigned resources to keep it running properly. 

You’ll find that if you prioritize making this acid cleaning and routine maintenance a recurring task, two hours once a month can save you a lot of headaches. Taking care of your sodium hypochlorite generator may not seem like much of a priority, but taking the time to clean and maintain it can save you a lot of money—and it can make your vessel a safer place to be. 

If you need assistance with maintenance, expertise to gauge the health of your system, or a great source for replacement parts, H2O, is here to help. Reach out to H2O, today for part pricing, questions, and anything else you may need.