GRP Panel Type Water Storage Tanks - Comparative Advantages

Durability

 GRP / FRP Panel water tanks

Fiber Glass Hand Lay-up water tanks

PVC water tanks

Steel water tanks

Concrete water tanks

§    No service failures reported in 25+ years.

§    Hot pressed sheet mould compound (SMC) at 150° C and 100 Kg pressure per cm² produce a uniform panel of solid homogenous construction.

§ Average serviceable life for panels in normal conditions without maintenance is  ± 40 years.

§ Tested for heavy impact, weather, loads, settling and earth quakes.

§ Safety factor of 8 x above maximum anticipated load.

§ Excellent ultra violet (UV) resistant characteristics and performance.

§ Option of pre-insulated panels to avoid the risk of freezing.

§ Hand lay-up manufacturing process is unable to deliver consistent quality laminate thickness and is dependant on the level of skills provided by labour. Even with skilled labour, homogenous laminate is almost impossible to attain which leads to a weak constructed tank.

§ Average serviceable life under normal conditions is  ±5 years; in variable climates with extremes of temperature this will be reduced even further.

§ Rough surfaces accelerate delamination of the fibers particularly when exposed to UV rays from sunlight.

§ Brittle in construction that results in damage.

§ Freezing results in cracking

§    Exposure to weather variations such as cold, heat and UV rays on a thinly walled tank, which has continuously changing water levels, causes embrittlement resulting in cracking and a short life.

§    Fragile and could be damaged by surrounding normal activities.

§    Due to the extreme lightness of the tank a normal light storm could break the connecting pipes and blow the tank away when it is empty. When used on a roof concrete block are placed in the tank to minimise the risk of being blown away by the wind when empty.

§    Freezing results in cracking

§  Exposure to weather variations such as cold and heat as well as varying water levels on the tank walls results in expansion and contraction creating cracks on the laminated surfaces which leads to a shorter life due to corrosion.

§    Lack of regular maintenance results in a short life for steel water tanks.

§    Freezing results in deformation and possible cracking.

§    Durable when no settlement or cracking occurs.

§    Concrete is highly absorbent of water. Heat and humidity above variable water levels in a closed tank increase absorption reaching the reinforced steel bars causing corrosion that leads to expansion and ultimately cracking of the concrete.

§    Concrete has high thermal conductivity, which in cold weather freezes water and results in cracking.

Water Quality

 FTC GRP / FRP Panel water tanks

 Fiber Glass Hand lay-up water tanks

PVC water tanks

Steel water tanks

Concrete water tanks

§    Smooth mirror surface of the panel prevent dirt adhesion and bacterial growth.

§    Light proof to prevent algae growth. Light transmittance for panels including manhole cover is 0,00%.

§    The hot pressingmethod for panels eliminates styreneand makes it an ideal product for storing drinking water.

§    Tanks are completely sealed, manhole covers and air vents are by design dust and insect proof.

§    No metal componentsneed to be in contact with water. Reinforcement, bolts and nuts for assembly are on the outside.

§    Exclusive base panel design ensurescomplete free flow drainage; this eliminates residual contaminated water with cleaning.

§  Rough surfaces encourage bacterial growth.

§  Dirt will adhere to the inside walls causing odors and contamination.

§  Light transmission through tank walls will encourage algae growth.

§  Poor production methods and raw materials cause material degradation that contaminates water.

§  Styrene emission causes health and environmental damage.

§  Bottom slope will not allow complete drainage of hose pressure water with chemicals used for cleaning resulting in contamination of incoming water.

§  Light transmittance through tank manhole cover will encourage algae growth.

§  Dust and polluted air through manhole cover corridor contaminates the water.

§  Bottom slope will not allow complete drainage of hose pressure water with chemicals used for cleaning resulting in contamination of incoming water.

§  Corrosion causes dangerous toxins in drinking water.

§    Residual chlorides causes chlorine gas when water pours into tank through inlet, this degrades both metal and water quality.

§    Bottom slope will not allow complete drainage of hose pressure water with chemicals used for cleaning resulting in contamination of incoming water.

§    Rough surface collects dirt and bacteria.

§    Light penetration from manhole results in algae growth.

§    Manhole gaps and corridors encourage breeding of insects and accumulation of dust.

§    Base line cracks result in water contamination.

§    Flat bottom will not allow complete drainage of hose pressure water with chemicals resulting in contamination of incoming water.

§    Chlorine causes degradation of the tank surface that provides room for bacteria growth.

Leakage

GRP / FRP Panel water tanks

Fiber Glass Hand lay-up water tanks

PVC water tanks

Steel water tanks

Concrete water tanks

§    Exclusive design of convex bottom panels with flexible rubber sealant is most effective against risk of leakage.

§    Modular panel with low thermal coefficient and flexible rubber sealant ensures a leak free design.

§    Accessible from all sides including bottom for easy visual inspection.

§    Putty used as water sealant material is normally of poor quality and can cause leakage.

§    Breakage occurs easily due to non-uniform surfaces and short life.

§   Fragile material that could easily be broken by normal work related activity.

§    UV degrades the material and is then easily broken.

§   Freezing breaks the material.

§   Weak points at welded joints lead to leakage problems with welded tanks.

§    Bolted steel tanks are susceptible to high expansion and contraction due to thermal properties, which will over time affect sealant causing leakage.

§    If corrosion is not corrected regularly it will eventually cause leakage.

§    Freezing will result is leaks at the joints.

§    Settlement and cracking results in leakage.

§    Base line leakage is difficult to detect resulting in serious damage and collapse of the tank.

§    Poorly sealed and maintained tanks will absorb water, which will corrode the steel reinforcement inside concrete causing cracks due to expansion and leakage.

§    Freezing causes cracking that will result in leaks.

Repairs & Maintenance

GRP / FRP Panel water tanks

Fiber Glass Hand lay-up water tanks

PVC water tanks

Steel water tanks

Concrete water tanks

§    Repair and maintenance can be done externally without interrupting supply.

§     Irreparable accidental damage will be solved by replacing damaged panel, with basic hand tools.

§    Partition inside tank allows continuous water supply during maintenance

§    Maintenance limited to outside bolt tightening/ and internal hose water pressure wash down without chemicals.

§    Complete water drainage by design.

§    Skilled workers are required to repair and clean the tank which takes a long time..

§    Quality of water lost by introducing newfiberglass with much resin and styrene.

§    Necessary to empty entire tank, interrupting water supply.

§    Patches give uneven surface, causing bacteria and algae accumulation.

§    Tanks do not drain completely after cleaning.

§    Tank must be replaced if broken or damaged, as it is not feasible to repair it.

§    Tanks normally do not drain completely after cleaning.

§    Needs frequent maintenance due to corrosion.  

§    Maintenance is often done with paint, which contains toxic chemicals.

§    Heavily corroded sections may need to be cut out and replaced which is a costly and time consuming exercise with long interrupted water supply periods.

§    Maintenance results in interruption of water supply.

§    Causes interruption of water supply.

§    Steel reinforcement is subject to corrosion and deterioration from water contact due to cracks.

§    Rough and uneven surfaces require hose water pressure for wash down with chemicals to kill bacteria and clean dirty surfaces.

§    Flat bottom will not allow complete drainage of hose pressure water with chemical, resulting in contamination of incoming water.

§   Costly to maintain.

§    Repair is only a temporary solution to leakage problems.

Adaptability of Size and Design

GRP / FRP Panel water tanks

Fiber Glass Hand lay-up water tanks

PVC water tanks

Steel water tanks

Concrete water tanks

§    Flexible sizes and shapes by design could range from 1 m³ to 10,000 m³.

§    Can easily be extended at any time as storage requirement increase.

§    Can be relocated easily from one location to another several times.

§   Limited to 4.00 mt in height

§    Flexible in size and shape dependant on volume.

§    Cannot be used for large size tanks.

§    Larger sizes impractical to relocate due to one-piece design.

§   Cannot be extended.

§    Pre-determined sizes.  Size limitation in the production moulding process.  

§    Not suitable for large tanks.

§   Cannot be extended.

§    Impractical to relocate due to one-piece design.

§    Flexible size and shape by design could range from 1 m³ to more than 10,000 m³.

§    Height can go up to 12 mt.

§    Cannot be moved from one location to another.

§    Cannot be extended in size or volume.

§    Flexible in size and shape.

§    Unable to increase size or volume.

§    Not relocatable.

Physical Properties

GRP / FRP Panel water tanks

Fiber Glass Hand lay-up water tanks

PVC water tanks

Steel water tanks

Concrete water tanks

§    Exceptional panel strength in compression, tension, torsion (Rigidity)

§    Panels individually designed for optimal performance with a safety factor of 8.

§    Designed and tested to withstand 100 years anticipated natural conditions in Japan.

§    Long life UV protection.

§    Low thermal conductivity.

§    Limited in strength compression, tension, torsion (rigidity)

§    Designed for low water pressure with a safety factor of 2.5 around.

§    Short life span.

§ No UV protection.

§    Manufacturing process does not cure styrene emissions.

§ Uneven thickness.

§   High thermal conductivity.

§    Limited in strength compression, tension, torsion (rigidity)

§    Designed for low water pressure with the minimum wall thickness  required to hold this capacity of water with a lower safety factor than Fiber Glass Hand Lay-up tanks.

§    UV protection is limited due to the wall thickness.

§    High thermal conductivity also due to wall thickness.

§   Thermal conductivity of steel is very high (240 times more than GRP), heating up tank and water and making handling, installing, and repair difficult.

§   Weight of steel calls for more extensive and costly support structures.

§    Susceptible to corrosion and high maintenance.

§    Expansion and contraction due to thermal properties will weaken joints over time.

§    Low seismic tolerances.

§    Long life expectancy in absence of cracks.

§    Flexible in Design.

§    Longer life in temperate weather conditions.

§    High thermal conductivity.

Corrosion Properties

GRP / FRP Panel water tanks

Fiber Glass Hand lay-up water tanks

PVC water tanks

Steel water tanks

Concrete water tanks

§ Not applicable (No steel in direct contact with water).

§ Not susceptible to corrosion.

§ Not susceptible to corrosion.

§ Highly susceptible to corrosion causing frequent and costly maintenance.

§ Materials used to rectify corrosion may be toxic.

§ Any process to protect the steel from corrosion is easily scratched as a result of accidents during handling and assembly which in turn cause corrosion.

§ Water absorption in poorly or untreated concrete tanks is high causing corrosion to the internal steel reinforcement that in turn causes expansion cracks to the concrete.

Handling & Assembly

GRP / FRP Panel water tanks

Fiber Glass Hand lay-up water tanks

PVC water tanks

Steel water tanks

Concrete water tanks

§ Lowest overall skill level of labour requirement. For assembly labour can be done by the local community.

§ Low man-hour labour requirement. e.g. (5x5x2 m = 50 m³) This tank requires 11man hours for assembly

§ Minimum assembly equipment requirement, using basic hand tools.

§ Panel is lightweight and easy to handle. Uniform quality end product.

§ Minimum volume and lightweight to transport, e.g. Pallet 2m³ = 400 kg to build a tank of 9 m³, transport volumes decrease proportionately per m³ as tank volumes increase in size.

§ Difficult to transport and place due to its one-piece design.

§ Very difficult to place on the roofs of buildings without the use of lifting equipment.

§ Costly due to the fact that volume is being transported.

§ Larger sizes difficult to transport and place due to its one-piece design.

§ Very difficult to place on the roofs of buildings without the use of lifting equipment.

§ Costly due to the fact that volume is being transported.

§ Special equipment required for lifting heavy plates that weigh three times that of a GRP panel. 

§ High skill level of labour is required as well as high total man-hours for assembly.  

§ Special tools and equipment required for assembly.

§ Long time and skill level of labour and equipment needed to complete tank construction. 

§ Building tanks in urban areas involves construction requiring the transportation of large quantities of materials, equipment and manpower.

§ Building tanks in remote areas require special utilities that are not always readily available as well as the requirements related to regular urban construction sites.

Insulation Properties & Characteristics

GRP / FRP Panel water tanks

Fiber Glass Hand lay-up water tanks

PVC water tanks

Steel water tanks

Concrete water tanks

§ Insulated panel option available for extreme weather conditions (hot or cold).

§    Excellent for industrial purposes where chilled water is required in volume.

§    Non-insulated Panels have 240 times less thermal conductivity than metal, ensuring stable temperatures.

§    Acceptable thermal conductivity properties in normal weather conditions, in climates where extremes of temperature are the norm the water delivered will be hot in summer and cold in winter which proves to be uncomfortable and inconvenient to the user.

§ Difficult to add insulation material due to designs.

§ Causes big variations in water temperature over a 24-hour cycle affecting water quality

§ Difficult to add insulation material due to designs.

§ High thermal conductivity.

§ Difficult to add insulation materials due to designs.

§ Causes big variations in water temperature over a 24-hour cycle affecting water quality.

§ Water temperature will be above ambient temperatures in summer and below ambient in winter.

§ Thermal conductivity of steel is very high (37 Kcal/M.Hr.C.), heating up tank and water and making handling, installing, and repair difficult.

§ Causes big variations in water temperature over a 24-hour cycle affecting water quality.

§ Water temperature will be above ambient temperatures in summer and below ambient in winter.

§ Acceptable thermal properties in temperate weather conditions.