Since its inception in 2001 by Professor Joe Quarini of the University of Bristol in England, Ice Pigging™ has become a popular pipe cleaning method. Many municipalities have begun using this method to help improve  water quality in their water distribution pipes and improve pumping efficiency in sewer force mains.

What is Ice Pigging™? Ice Pigging™ is a cleaning process that utilizes slush ice (or an ice slurry). This slurry forms a semi-solid plug which is referred to as the “ice pig.” This ice pig makes its way through a pipe and cleans it using up to 1,000 x more shear on the internal pipe wall. 

How does Ice Pigging™ work? And what is the actual Ice Pigging™ process? You might now know what this procedure is, but you need to learn more about how it is done. In this article, we’re going to provide a step-by-step guide detailing how Ice Pigging™ is utilized to clean pipes and answer a few of the frequently asked questions surrounding the Ice Pigging™ procedure. 

A Step-By-Step Guide To Ice Pigging™: How It Works

Below we have discussed how Ice Pigging™ works to help those interested in the Ice Pigging™ procedure understand more about this innovative, advanced pipe cleaning method. 

However, before we delve into the step-by-step guide, we would like to explain that “pigging,” (although an odd word for this procedure) is a means of sending a solid object (pig), similar in shape to a rubber bullet, through a pipe to clean it. Modern pigs come in all shapes and sizes and are designed to maximize the cleaning effect in any given situation.

Since an ice slurry is a more flexible material, it is generally easier to insert into a pipe. Let’s now look at the steps. 

Step One

The first step pipeline cleaners will take when tasked with cleaning a municipality pipeline using the Ice Pigging™ method is to isolate the main. A technician will close the valves upstream and downstream, plus any connecting intersections.

After the main is isolated, the vehicle holding the ice slurry — a semi-liquid made with many ice crystals — will be pumped by the operators into the isolated section of the main pipeline. This will be completed via simple 2.5” fire hoses that run from the vehicle holding the ice slurry to the hydrant stand post. 

Step Two 

While the ice solution is traveling down the hose and directly into the isolated section of the main, the operators and technicians will continuously monitor it and the main’s pressure. This ensures that no pipe bursting occurs while the ice slurry is being injected into the main due to excess pressure. 

After all the ice slurry has been pumped into the main, a technician will open the upstream valve. This will allow the upstream pressure to push the ice pig all the way to an exit point along the pipeline. While the ice pig is traveling along the pipeline, it is carefully monitored to ensure that the Ice Pigging™ procedure is completed successfully. 

Step Three

During step three, the ice pig travels through the pipeline and removes sediment, iron, manganese and biofilm that has accumulated in the water main over the years by lifting it in the body of the ice and flushing it out. 

As an ice pig makes its way to the exit point, the sediment it has picked up is sent directly into a local sanitary sewer or diverted into large tankers that collect the dirty material. This dirty sludge is later disposed of in an environmentally-friendly manner. 

Step Four

The last step in the Ice Pigging™ pipeline cleaning method is to flush the main after removing the sediment. The pipe will be flushed for a specific period of time until all the ice and sediment is flushed from the main and then a little longer as determined by the water company to ensure the water continues to meet strict water quality standards. Once it has been flushed and is deemed safe for use, the pipeline will be returned to service immediately. There is no requirement to disinfect the main.

What Are the Common Reasons for Ice Pigging™?

Now that we have discussed the step-by-step procedure of Ice Pigging™, it's time to look at the common reasons why municipalities choose Ice Pigging™. Have a look below to learn more. 

• Ice Pigging™ uses a fraction of the water that flushing and conventional pigging does, making it more environmentally friendly.

• Ice Pigging™ can be used for decommissioning cleaning when pipework needs to be cleaned of all residue sediment before it is dismantled.

• Ice Pigging™ can be completed when a pipe needs to be cleaned because its use will be changed or if a new product will be used in conjunction with the original piping.

• Ice Pigging™ is used to aid with asset management by extending the life of a pipeline to ensure capital spent on pipes and pumps is kept to a minimum.

• Ice Pigging™ is perfect for removing accumulations of sediment, biofilm, and foreign objects that are affecting water quality. For example, to improve odor, taste, and lower turbidity levels as well as improve chlorine residuals.

• Ice Pigging™ can be employed when a major piping overhaul is planned, and a deep clean of a pipe network is required.

• Ice Pigging™ is ideal for improving a sewer force main pumping efficiency by reducing back pressure and increasing flows.

How Is Ice Pigging™ Different from Traditional Pigging?

Despite what many might believe, Ice Pigging™ is different from traditional pigging. Unlike traditional pigging, Ice Pigging™ carries much less risk because it is inserted and removed via existing pipeline fittings. There is an increased chance for risk and disruptions to a pipeline with conventional and foam pigging. 

For example, there are installation and launching chambers required, and if the pig or swab gets stuck, a team will have to spend time to locate it then reverse the flow to move it back to the launcher or in the worst case dig it up. In contrast, if the ice pig were to get stuck in a pipeline, the ice would simply melt without causing any problems to a pipeline's infrastructure. 

Ice Pigging™ is a far less disruptive pipe cleaning method because a pipeline outage will only take a few hours compared to a few days with other pipe cleaning methods. This means water is restored faster with Ice Pigging™. Interestingly, Ice Pigging™ doesn’t require a lengthy chlorination process, so a pipeline can be returned to service immediately after being cleaned. 

What Are The Limitations of Ice Pigging™? 

Although Ice Pigging™ is a much-preferred pipeline cleaning solution, it does have limitations. According to a study, Ice Pigging™ is currently only advisable with pipes that have diameters of up to 24 inches although current capabilities mean Ice Pigging™ can effectively clean up to 2.5 miles of 6-inch PVC pipe per day.

The ice pig is not as aggressive as some conventional pigs, meaning that hard calcified sediment buildup may not be possible to be removed using ice.

Get In Touch With American Pipeline Solutions for Your Ice Pigging™ Needs

As you can see, Ice Pigging™ is a somewhat complex pipeline cleaning method that needs to be performed by professionals to avoid pipeline damages and disruptions. Should you want to learn more about the Ice Pigging™ pipe cleaning method, you can talk to the experts at American Pipeline Solutions. 

Our company specializes in pigging solutions and is recognized as a leader in the industry. We are the only company in the United States that offers this service. You can contact us here, and we will get in touch with you. 

Or, to get a head start, please complete this questionnaire and return it along with supporting maps to: paul@americapipe.com