The most commonly cause of this the drift eliminators are damaged or installed incorrectly Water splashing from the cooling tower creates a number of problems, some of these are.
- Waste of water from the cooling tower circuit
- Safety slip hazard on the ground
- Waste of chemicals added to the water for micro biological control
- Corrosion of adjacent plant due to high levels of chlorine in water
- On or a combination of these issues will lead to a non-compliance with local governing authorities
If there is water on the outside of the cooling tower and doesn’t appear to be coming out of the drift eliminators, this could be coming from casing leaks, blocked distribution nozzles that are causing overflows from the sump, or broken fill and eliminator panels. Sometimes it could even be incorrect cooling tower fan operation. All these problems can be repaired by experienced cooling tower repair technicians, with access to the correct spare parts and knowledge of the cooling tower operation. If water is being emitted through the fan cylinder and exiting to the atmosphere, the most common cause of this is excess water flowing through the cooling tower, possible under sizing of the cooling tower, or broken or damaged eliminator panels
Eliminators are designed to prevent water that is flowing through the cooling tower fill pack, being caught in the air stream and water droplets exiting through the fan cylinder. Australian Standard AS 3666.1-2011, specifies the maximum amount of allowable “drift” coming from the cooling tower. Some manufactures have the eliminators incorporated into the PVC fill sheets, thus just because your cooling tower appears not to have separate eliminators, it might not mean they do not have any eliminators at all. If the eliminators in your cooling tower appear to be damaged or broken they can be easily replaced.
Where cooling tower exist in residential applications, hospitals, or other areas that are noise sensitive, it is best to specify a low noise cooling tower. Low noise is achieved generally by slowing the fan speed down, and increasing the size of the actual fan blade. This decreases the velocity of the air flowing through the cooling tower. Achieving low noise is a compromise between fan efficiency v cooling tower thermal performance. After market air attenuator’s and splash decks can also be fitted. Special low noise requirements need to be calculated by an experienced team of engineers who are able to determine all the cooling tower parameters and achieve the cooling tower optimal design, whilst meeting the low noise requirements.
Marley Flow Control are exclusive agents for SPX Cooling Technologies on the eastern sea board of Australia and all of New Zealand, We have access to the latest innovative computer software via the SPX “BEST” sizing program. If you wish to have access to this software, please contact us through our web site www.marleyflow.com.au or email us at email@example.com Alternatively we can size and optimize a new cooling tower for you via our dedicated engineering team, who are contactable via the same methods.
Generally the answer is “YES”. However the fill pack in your cooling tower may need to change from say a film fill to a splash fill. Low Clog film fills are also available. Changing from a film fill to a splash fill will increase the physical size of the cooling tower. For sizing of the cooling tower a comprehensive water analysis of the water being used in the cooling tower is required by the manufacturer prior to selecting a cooling tower. Additional cooling tower cleaning and chemical dosing may also be required.
Modular or package cooling towers have been designed to be assembled in either a designated assembly location or an on site location. Marley Flow Control have performed numerous cooling tower retrofit projects, where the existing old cooling towers are demolished on site and removed in sections, which can fit into a lift or down a stairwell. The new cooling tower can be installed in much the same way, by delivering all the cooling tower components to the existing plant room / or roof top location and assembling the cooling tower on site?
As the name implies a forced draft cooling tower “blows” air through the cooling tower, whereas an induced draft cooling tower “sucks” the air through the cooling tower. Forced draft cooling towers use up 40% more energy than an induced draft cooling tower, but have a smaller foot print than even a counter flow cooling tower. They are typically used in enclosed plant rooms, where floor space is at a premium.
Smaller HVAC cooling towers are made from a variety of materials, including fibreglass, galvanised steel and various grades of stainless steel. The fill and eliminators are generally manufactured from PVC. The choice of materials is based on commercial considerations. Galvanised steel is the most economical material to manufacture a cooling tower from. However in the long term galvanised steel is more susceptible to corrosion and has the shortest life span of any cooling tower. Fibreglass is the next best option for an economically priced cooling tower, but even the best UV stabilised fibreglass material do deteriorate in sunlight and the gel coats are fragile and prone to cracking, they cannot be fire rated and are made from non-recyclable products . Stainless steel is becoming a popular choice for a cooling tower construction material. It does not corrode, it does not suffer UV instability and is very robust in construction FM approved and fully recyclable. However it is the most expensive cooling tower construction material. If total service life is taken into consideration, stainless steel should be considered an economical option. Larger industrial cooling towers are manufactured from either treated timber or fibreglass pultrusion. Both materials have advantages. Timber is a sustainable and a renewable resource, but chemical treatment and handling may be hazardous. Fibreglass pultrusions are a non-renewable material and can still deteriorate in certain instances, such as geothermal or salt water applications.
This is a commercial consideration, belt driven fans are more economical to purchase, but have a much higher maintenance cost and possible reliability issues. Drive belts can also be noisy and readily break quickly, if the alignment of the motor pulley and fan drive pulley is only marginally not correct. Gearboxes are very reliable and quiet. Modern gearboxes can have up to 5 year oil changes if the correct mineral oil is used. In recent times there has been a move toward direct drive induction electric motors. An induction motor is expensive and if retrofitting into a cooling tower the mechanical support they are mounted to needs to be upgraded to allow for the additional weight of the induction motor. An induction motor can use up to 10% less energy than a conventional electric motor.