The ZipaTank™ is an innovative bolted modular tank developed by Glencore Technology to meet the tough requirements of slurry storage and leaching tanks in the mining industry. The ZipaTank™ incorporates an elegant modular design with simple mechanical joins to provide all the benefits of a traditional welded tank, with lower costs, reduced installation times and far greater flexibility.
The ZipaTank™ consists of a base assembly and panels that are joined vertically to form the individual strakes of the tank. The assembled strakes are then joined horizontally to complete the tank shell.
The base assembly is provided as prefabricated sections inclusive of the annular ring for joining at site by welding. This is the only welding required for the construction of the ZipaTank™ and is carried out at ground level.
All tank ancillaries, such as man doors, nozzles, baffles and overflow system are fabricated into the panels under controlled factory conditions. Baffle and riser sections are connected to the strakes progressively as they are assembled. All ZipaTank™ components are designed to be containerised for easy transport.
All components of the ZipaTank™ are fabricated off site and shipped to site in modular sections for assembly. Little or no site welding is required. Off site fabrication significantly reduces the cost of the ZipaTank™, relative to a site welded tank.
The ZipaTank™ can be designed for any size of tank and can be tailored to meet a client's requirements. A wide range of materials can be used in the construction of the ZipaTank™, ranging from mild to alloy steels and titanium. The ZipaTank™ can be installed for a large tank in 1 to 2 weeks.
The ZipaTank™ consists of a series of panels that are locked together to form the tank shell and the tank base. The ZipaTank™ shell consists of panels that are joined vertically to form the individual strakes of the tank. The assembled strakes are then joined horizontally to complete the tank shell. Each panel is manufactured from a single section of mild or alloy steel at a height of approximately 2 metres, and at a width designed to fit in a standard shipping container. The panels making up the tank shell are curved to match the required diameter for the assembled tank. Each panel is supplied with any attachments, nozzles, flanges or stabilising rings prefabricated into the panel. All panels are painted or lined in the factory prior to transport to site.
During assembley, the base panels are first jointed, and located on the tank foundation using holding down bolts. Individual strakes are then assembled at ground level, with the ZipaTank constructed from the top strake downwards. All assembley occurs at ground level and no scaffolding or working at heights is required to assemble the ZipaTank™.
All panels are then locked together using a range of specially developed mechanical joins, depending on the application. All of the ZipaTank™ mechanical joins are rigorously designed to provide a leak free joint that is as strong as a welded joint. The ZipaTank™ also has a range of modular accessories, from access manholes, baffles, slurry risers and launders, access ways and ladder ways, agitators and agitator support and maintenance platforms.
The ZipaTankTM Mechanical Joining Systems
A range of mechanical joins are used to construct the ZipaTank™, ranging from conventional bolted flange connections for many of the ancillaries, to specially designed joins for the panels that make up the ZipaTank™ shell.
The principle stress acting on the ZipaTank™ shell is hoop stress, resulting from the hydrostatic pressure of the contents of the tank. The joining systems developed to connect the ZipaTank™ panels are based on shear connections to accommodate the hoop stress in a simple, robust and economical manner. The two most common mechanical joins – the Bolted Lap Join and the
Joinlox™ join are described below.
Bolted lap Plate Join
The bolted lap plate join is a butt join, where the edges of the panel are butted together and then inner and outer cover plates are applied across the join. Laser cut holes in the edges of the panel accommodate studs fitted to the inner cover plate, and these studs then penetrate through the panel and through the outer cover plate. Nuts are then fitted to the studs to complete the join. The stud bolts act in double shear due to the inner and outer cover plates.
JoinloxTM Compression Join
The Joinlox™ Compression Join is an innovative joining method that was developed in partnership with Joinlox™.
The joint consists of two interlocking saw tooth sections fabricated on each vertical edge of the panel, which are brought together and then locked in place with a wedge and shear key. The shear key acts against lugs attached to the outer surface of the panel.
The wedge, lugs and shear key are located on the outside of the panel, away from the contents of the tank, making the Joinlox™ join ideal for highly abrasive slurries.
Both ZipaTank™ joining systems are entirely mechanical, and no site welding is required to assemble the ZipaTank™ shell Extensive quality control is carried out during fabrication of the panels in a controlled factory environment to ensure that the site assembly process is quick and efficient.
The ZipaTank™ can be used in a wide range of applications in the mining industry, including the following:
Single tank slurry storage applications:
- Concentrate storage and conditioning tanks
- Thickener underflow storage tanks
- Limestone and lime slurry storage
- Reagent storage
- Filter cake repulp
- Tailings processing
- Flotation tanks and equipment
- Thickening and clarification tanks and equipment
Multiple tank leaching applications:
- CIP/CIL processing of gold ores
- Acid leaching of copper oxide ores and tailings
- Acid leaching of uranium ores
- Acid leaching of zinc calcines
- Sulphide oxidation plants (Albion, BIOX)
The ZipaTank™ can be designed for any size of tank and can be tailored to meet a client's requirements. A wide range of materials can be used in the construction of the ZipaTank™, ranging from mild to alloy steels and titanium.
All ZipaTank™ components are designed to a minimum standard exceeding API 650, AS1210, AWWA-D103, AS3990 or BS 2654 (1989), depending on the application. All welds are designed in accordance with AS1554.1 or the relevant ANSI standard.
All designs incorporate relevant site factors, such as wind, snow, rain and seismic loads. ZipaTank™ dimensions are customised to suit the clients' needs.
Finite Element Analysis and destructive testing is carried out to confirm all design
The ZipaTank™ is designed to withstand the buckling loads associated with overhung agitators and other structural steel components, to allow mounting of these components directly onto the tank shell.
Each ZipaTank™ component is manufactured in a controlled factory environment using high quality materials. All panel profiles and penetrations are laser cut for accuracy. A range of fabrication material can be used for the ZipaTank™, including mild steel, stainless and duplex steels and titanium.
All ZipaTank™ panels can incorporate low cost lining systems, which are applied under controlled factory conditions. Conventional and high build epoxy paints, polyurethanes, rubber, GRP, FRP or more specialised materials can be used for the lining system. All linings are applied in controlled temperature and humidity rooms to ensure a consistent thickness and a competent bond to the parent plate.
Trial assembly is included in each ZipaTank™ supply to ensure that the site assembly process is trouble free.
The ZipaTank™ can be assembled on a conventional tank foundation, such as an in filled concrete ring beam or slab. A flexible gasket is placed between the tank floor and the tank foundation and sealed at the floor edge to prevent slurry or water contacting the underside of the tank floor.
Glencore Technology will assist in the design of the tank foundation, by providing general arrangements for the tank foundation, indicative hold down bolt drawings and design loadings.
ZipaTank™ Transport and Assembly
All ZipaTank™ components are fabricated in modular sections designed for transport in standard 40 ft open top shipping containers.
ZipaTank™ assembly follows a top down approach, with the agitator platform and top strake assembled first and connected. Lower strakes are then assembled on temporary work platforms, and the agitator platform and higher strakes lifted onto this strake for connection. All work is carried out at ground level using platform ladders. An assembly sequence is shown below.
Assembly does not require specialised labour and an installation supervisor can be provided by Glencore Technology. No special tools are required for the assembly of the ZipaTank™, and the tank can be assembled with a mobile crane and a crew of three or four workmen.