Chemical Containment

Fibreglass Tanks for HFA storage

Project Date

Industry

Products

2012

Chemical Plants, Fertiliser Plants

Fibreglass Tanks


Challenge

Tanks were needed for the safe storage of highly corrosive >25% Hydrofluoric Acid after manufacturing. 

Solution

Fibreglass Tanks designed and manufactured to meet the most stringent standards. Safety rails & FRP grating at the top of the tank for built-in, long-term access & health & safety considerations. 

Outcome

The clients have been very happy with the tanks' service and ease of maintenance.  

Concrete rehabilitation & lining at Napier WWTP inlet works

Project Date

Industry

Products

2012

Wastewater Treatment Plants

Armaline 3730 Coating System


Challenge

Napier City Council's concrete milliscreen plant was in need of repair. The concrete had been badly eaten away by hydrogen sulphide gas - more than 20mm in places. Additionally the timeframe to was extremely tight to minimise shutdown, required a 15 year warranty and the lining application had to be curable underwater in case of emergency overflows during applications.

Solution

We rehabilitated the concrete structures underneath their milliscreen plant that screens all of the sewage from Napier before being sent out to sea. This is the first part of a project that will include the building of a new wastewater treatment plant.

Outcome

Without being able to inspect the job fully beforehand and in difficult conditions and to a tight timetable, our team finished on time and to a high quality finish. Inspections a year later showed very little signs of wear, and very few minor points for touchup. Twice-yearly inspections will continue through the 15 year warranty period.

An excellent result on what was a very difficult project
— Johan Elhers

Testimonial

Fibreglass Sewer Liner Installed at Sporty’s Bar

Project Date

Industry

Products


Challenge

An existing sewer manhole was suffering from major corrosion issues both to the concrete and also the iron step rungs. The contractors (City Care) undertaking the repairs wanted to minimise disruption to traffic and patronage to the sports bar next to it.

Excavation and replacement of the manhole was considered and discarded for the following reasons.

  1. Manhole was 1050NB and 6m deep.
  2. Manhole was located approximately 3m from the edge of the road effectively in the left wheel track.
  3. Manhole was directly in front of a sports bar with regular clientele.
  4. Excavation to the depth of the manhole would require road closures and affect the footpath and entrance to the bar.
  5. Major resealing of the road would be required.

Solution

The solution was for us to make a 910NB fibreglass sleeve complete with fibreglass ladder attached. Traffic management was put in place to allow for partial closure of the road so the existing manhole top could be removed (approximately a 2m square cut in the road surface). City Care removed the iron step rungs. The fibreglass sleeve was lowered into the manhole and an epoxy grout used to seal around the bottom edge. Once a few small pipe connections were made through the fibreglass, the annulus was filled with a concrete slurry. The underside of a new concrete top was coated with our Armaline epoxy coating before being installed. City Care then reinstated the road surface.

Outcome

The manhole was repaired with minimal traffic disruption and without the requirement for the sports bar to close or lose business during the works. In fact, the patrons of the bar sat and watched out the front window with interest. City Care and the New Plymouth District Council were very pleased with the ease of the repair and the finished product.


Fibreglass Valve Chamber at Christchurch

Project Date

Industry

Products

2013

Sewage Networks

Fibreglass Valve Chambers


Challenge

Valve chambers are required to be installed underground alongside pump stations in earthquake liquefaction zones in Christchurch. They protect the valve equipment yet provide access for servicing. Earthquakes largely destroyed the wastewater network of Christchurch, and these valve chambers were an integral part of the re-build.

Solution

The flanged underground valve chamber was designed to withstand the large liquefaction loads imposed by the devastating shallow earthquakes. The valve chambers are anchored to both an underground concrete slab and the fibreglass pump station, restricting differential movement in the event of an earthquake.

Outcome

To date installations have withstood dozens of smaller aftershocks without damage.


Fibreglass Sewer Liner for Whangarei Manhole

Project Date

Industry

Products


Challenge

A new concrete manhole was installed on a long residence sewer from Whangarei Heads back to the treatment plant. However the concrete was severely corroded in less than one year due to hydrogen sulphide gas attack. The contractor was issued with a notice to rectify and achieve a design life of 50 years. The sewer was already live and could not be taken out of service for more than a few hours at a time using plugs and turning off stream pump stations off, using the storage  capacity of the network only.

Solution

Armatec supplied a FRP Liner to lower into the manhole and form a new manhole surface inside the existing one. The top of the manhole was removed, the liner fitted, and then the cavity between the FRP Liner and the old manhole was grouted. This was all done during daytime hours with the sewers plugged. At night time the plugs were removed and the sewer flowed as per normal, minimising disruption and costs.

Outcome

The manhole now has an all fibreglass inside surface that is totally impervious to hydrogen sulphide attack. The expected life of the manhole is now in excess of 50 years.


Fibreglass Cover Installation at Careys Gully, Wellington

The two sludge tanks at Carey’s Gully store sewage sludge pumped from the Moa Point wastewater treatment plant located about 10 kilometers away. Due to the age of the sludge, considerable quantities of corrosive hydrogen sulphide gas are released within the tanks. H2S concentrations over 50 ppm have been recorded, and resulted in severe corrosion to the concrete walls and concrete roof of these two tanks. 

Petrochemical Storage Tank Lining

The bottoms of the steel methanol storage tanks were becoming badly pitted due to water accumulation at the base of the tank, to the point where the storage security of methanol was in question. The epoxy coating previously installed 8 to 10 years earlier had failed.

Dairy Industry Chemical Wastewater Drains in Fibreglass

Underground wastewater drains from Dairy Factories need to handle a range of acidic and caustic solutions, at temperatures up to 90ºC. Traditional materials such as earthenware, plastic and stainless steel had all proven unsatisfactory, resulting in leaks of chemicals into the ground.