Ice Pigging™ - the fastest and safest method of cleaning drinking water pipes deployed in Asian cities
Potable water contains minerals which settle down over time in the pipelines. SUEZ's ice pigging technology helps clean the internal surface of the pipes to remove these mineral sediments, which may accumulate over time. Such cleaning methods are non-intrusive, fast, effective and economical.
Since the launch of Ice PiggingTM over 10 years ago, it has been successfully deployed in the water industry in many countries including the UK, and Australia. In Asia, SUEZ is in the process of expanding its service for municipal water networks with contracts in Singapore, Mainland China, Hong Kong and Taipei.
Drinking water pipes need cleaning for several reasons. Occasionally when a trunk main’s flow is reversed, many years of accumulated sediment will be suspended, leading to increased turbidity or lack of clarity, potentially affecting thousands of consumers. Another reason is when there is an older infrastructure. Changes to the network like overhauls, changing flow rates, bursts and valve operations can also trigger the need to clean pipework. Biofilm build-up can lead to many issues like an increase in bacteria levels and a loss of chlorination levels which indicate that the mains need cleaning.
Ice Pigging™ is a highly effective pipe cleaning technique in which ice slurry is moved through the network to remove unwanted material, sediment, or product residues from the pipe.
Ice Pigging™ utilises a two-phase ice slurry, which is pumpable like a liquid, but forms a semi-solid 'pig' within the pipe. The Ice Pigging™ is capable of navigating complex pipework which may incorporate changes in pipe diameter, bends, valve systems and other obstructions with no risk of becoming stuck. It is fast, effective and exceptionally low risk (it just melts away), using significantly less water than many other techniques.
Singapore: SUEZ's first ice pigging project in Asia
In 2018, SUEZ was awarded a three-year contract by PUB, Singapore's National Water Agency, to clean its water supply pipelines using the ice pigging technology. In 2021, PUB awarded SUEZ with another three-year contract to provide a range of preventive maintenance techniques including data gathering of the water pipe network, real-time water quality monitoring, valve exercising and the application of ice pigging.
Hong Kong: Highly efficient cleaning of seawater pipework
In Hong Kong, SUEZ used the ice pigging technique to clean 1.4 km long ductile iron and PE pipes for Hong Kong’s Water Supplies Department (WSD). The pipework consisted of 650 m of water supply pipes and 750 m of seawater pipes with diameters ranging from 150 mm to 300 mm. SUEZ was able to finish cleaning these pipes within one week. This project demonstrated that the ice pigging technology could effectively remove sediments and biofilms which settled and attached to the internal surface of the pipes and were very difficult to remove with a conventional flushing method.
Taiwan: SUEZ has partnered with Taipei Water Department on three occasions
In 2019, SUEZ was entrusted by Taipei Water Department to clean 20 km of 100-mm to 300-mm DI and HDPE water pipes in Taipei, Taiwan's most densely populated city. To overcome challenges in cleaning pipes in such an urbanised area, SUEZ proposed the ice pigging technique to be used. With a formulated cleaning plan, a set of five-tonne ice making machine and an ice delivery truck, SUEZ was able to complete the pipe cleaning works within just two months.
With a great success in the first project, the ice pigging technology earned the trust and recognition from Taipei Water Department and SUEZ was thus again commissioned to have cleaned 30-km water pipes in 2020 and 40-km water pipes in 2021.
Chongqing: Complex pipework cleaning in community courtyard
SUEZ entered Chongqing after deploying the ice pigging technology in Taipei and Hong Kong. SUEZ cleaned 5 km of water supply pipes (ductile iron, diameters ranging from DN100 to DN300) for Chongqing Sino-French Water Supply within nine working days. The cleaning area involved the municipal network of roads and clusters of residential quarters.
To avoid inconvenience from water outage to the users, SUEZ decided to carry out the cleaning operation in the night time.
Furthermore, there were parts of the network which go through the residential quarters making cleaning activities more complicated. Thanks to the ice pigging technique’s efficiency and flexibility, the team could successfully clean intricate pipelines in the complex's courtyard without issues.
Yixing: SUEZ cleaned pipes in residential area within two days
In Hufu Town, Yixing (Jiangsu Province), SUEZ provided the ice pigging technology for the cleaning services of DN110 and DN160 water supply pipelines in a residential area. SUEZ’s ice pigging team was able to clean 1.3 km network within just two days although this was the first pilot project SUEZ ever did in Yixing. Following this successful project, Yixing Water Group anticipates further application of the ice pigging technology in pipe cleaning in other parts of the city.
Ice Pigging™ is considered the Best Available Technique for many pipe cleaning situations as it radically decreases the time involved and for the quality of clean.
SUEZ’s Ice Pigging™ technology uses a pumped ice slurry to physically clean pipes, sweeping and removing settled and loosely adhered deposits. This unique 'no-dig' solution delivers superior cleaning results, is safe and gentle to pipes, and requires about 50% less water than conventional flushing techniques. More importantly, its quick deployment significantly reduces chances of customers being adversely affected during cleaning operations.
Through innovation, the local team has developed an adjusted ice pigging technique that suits the tropical climate of Singapore, demonstrating ice pigging’s efficacy at cleaning potable water pipes year-round.