Nordic Water’s Zickert Technology Gives New Lease Of Life To 70-Year Old Argentine Water Treatment Facility
The transformation of the sedimentation tanks at one of Argentina’s most significant water treatment facilities is now complete.
The installation of Zickert sludge scraper technology from Nordic Water, a Sulzer brand, has increased capacity, greatly improved reliability and decreased environmental impact.
The Donato Gerardi treatment plant, built in 1950, provides drinking water to 800,000 people in the Buenos Aires province of Argentina.
However, the facility’s age was starting to become apparent as it approached its 70th birthday.
Operator Aguas de Buenos Aires SA (ABSA) was aware that significant upgrades were needed because the performance had deteriorated over the years.
The state-owned utility hired the international water and energy specialist Veolia in 2017 to carry out a thorough renovation of the building.
The project’s objectives were to boost capacity, implement new technologies and deliver a facility that was equipped to handle the demands of the twenty-first century.
The 14 massive concrete sedimentation tanks at the plant were a major focus of the upgrade program.
The neighboring Rio de La Plata serves as the source of water for the Donato Gerardi facility, and the raw water contains significant and fluctuating amounts of suspended particles.
These tanks would quickly build up significant amounts of sludge that could only be removed manually with hoses during the rainy season, when turbidity levels frequently rise to 500 NTU.
As a result, the sedimentation system would frequently become overburdened.
ABSA and the contractor intended to address the issue by installing a cutting-edge, automated sludge removal system.
They decided to use the Zickert technology from Nordic Water following a competitive tendering process.
Concentrated advantage
A reciprocating framework of hydrodynamically formed profiles set on the bottom of a sedimentation tank is how the Zickert bottom sludge scraper works.
These profiles grab the layer of heavily concentrated sludge at the bottom of the tank and transport it in one direction, toward a disposal exit.
In the other direction, the profiles’ form enables them to move through the muck with little disruption.
With less waste for the operator to manage and greater process efficiency overall, this mode of operation enables the scraper to remove waste with very high solids concentrations.
The Zickert system is also incredibly straightforward and reliable.
Only four moving parts make up its drive system, which is powered by a single hydraulic actuator.
There are no bearings, gears, chains, or other mechanical parts that could be vulnerable, so energy consumption is low.
ABSA was confident in the Zickert system’s performance because it had tested various scraper systems side by side at one of its sites and had already implemented the technology at a number of other plants throughout Argentina.
The findings showed that, in terms of solids removal and sludge concentration, Zickert provided the optimum option.
The tanks at Donato Gerardi had been constructed with a V-shaped base profile, which wasn’t intended to support a bottom-mounted scraper system. This was the only catch.
Setting the baseline
Nordic Water and Veolia came up with an easy fix for the compatibility issue.
Each tank’s bottom profile was filled with lightweight concrete to make a flat surface for the new scrapers.
This procedure was carried out one tank at a time, allowing the other 13 units to continue operating, in order to maintain plant functionality throughout the upgrade.
Two scrapers each were installed in the plant’s 42 by 11 meter tanks, for a total of 28 scrapers supplied to the project.
Since their installation, they have worked well, removing 400 m3 of sludge on average per hour from the raw water and ensuring that turbidity never rises above 3 NTU at the decanters.
With the labor-intensive task of manual tank cleaning eliminated thanks to automation, the amount of solids in the sludge produced by the system is more than twice what it was previously, which significantly reduces the time and energy needed to transport the waste for proper disposal.
The new system has nearly doubled the plant’s capacity, from 8,000 to 15,000 m3 of clean water per hour, as part of the site-wide changes.
Clear benefits
According to Daniel Castro, plant manager at ABSA, “Zickert sludge scrapers have a history of good performance at many of our other sites, so we were confident the technology would deliver at Donato Gerardi too.
” We now have access to a highly effective scraper system since Nordic Water supplied us with competent technical and practical help during this project.
The refurbishment was a significant, intricate job on a working plant.
The quickness and ease of installation of the Zickert system are just one of its numerous advantages.
The solution provided by Nordic Water was effective, dependable, and environmentally responsible.
According to Javier Casal Mosquera, technical manager of Nordic Water LA, “We have collaborated with ABSA extremely well for many years.”
“I’m incredibly proud that our technology was chosen for such a significant project, and that we were able to provide exactly what our customer needed to solve a persistent problem at this facility.”
About Sulzer
Sulzer is a global leader in fluid engineering. It specialize in pumping, agitation, mixing, separation and purification technologies for fluids of all types.
Source: Sulzer
