Evaporative Condensers for ammonia condensation project
Ammonia systems are the most efficient systems available for industrial-scale refrigeration facilities and allow the condensation process to be carried out at a temperature closest to the wet bulb temperature. Any modification of the condensing process increases or decreases the facility's efficiency coefficient by about 3%. Evaporative condensers can reduce the condensation temperature by 5-7 degrees centigrade, which means an energy saving of approx. 15-20%. On the other hand, ammonia is a dangerous and odorous substance and misuse of it can cause disaster to the point of injury. The most stringent standard requirements, pose to manufacturers of any component of the ammonia system a considerable challenge.
Pictured: Evaporative condensers.
The objective
To add four new evaporator condensers to the factory’s ammonia system at the of Tov facility in Beit Shean, located in the northern Jordan Valley, for the sake of upgrading the plant.
The challenge
This plant has been already operating evaporative condensers that were supplied by a competitor. We have studied the structure of competitors' condensers in depth and discovered, that it carries quite a few problems, that are equipment does not encounter. The competitors’ model was built in a mixed way: The initial cooling phase was done within a plastic container, that caused for colder air to reach the heat exchanger that thickens the refrigerant. This design allowed to downsize the condensation cluster, which is the most expensive part of the condenser and trim the entire equipment. This method certainly produced results in a laboratory environment, but subjected to real environmental conditions, where air saturated with sand and soil bits, the condensing coil which is exposed to outdoor conditions, becomes very quickly polluted and loses its required efficiency.
The Project’s Solution
Considering all those parameters, we have decided to submit the client an offer, focusing on the inherent advantages that the equipment of our ecosystem’s partner, EVAPCO renders to the plant operations. Our condenser’s built-in heat exchanger gets also polluted, but ours is protected by means of a droplets shield and possesses a much larger heat transfer area.
an equivalent thick fouling layer that builds-up on our heat exchanger’s cluster, is less harmful and has a much larger heat transfer area.
Accurate identification of the problem at hand
The fan motors of the competing model are located about 4-5 meters above the ground, which make reaching and handling them very difficult. The access to the engines is through the condenser itself. Just to take a closer look at the engine or the fan, it is necessary to squeeze through a small door a huge ladder and afterwards to remove it. In case of a motor malfunction, it is very difficult to detect it, unless one performs a daily inspection while climbing to a 5-meter elevation. I case the fan loses its balance, it would be only detected by the loud noise it will produce from above and the damage then might already be irreversible.
Our offer
When we identified this problem, we proposed a model with “pushed” engines and fans, assembled at the bottom of the unit, on a level where maintenance staff pass daily numerous times. The slightest abnormal rustling in the driveshaft, would immediately draw their attention and be addressed on the spot. The fans and engines are accessible from the ground level and the handling is performed from outside of the unit without the need to set a foot in it. Moreover, the old competing units with the small heat exchanger, are equipped with large, power-gobbling fan engines. We headed a different path. Of a series of dozens of models offered by EVAPCO, we have selected a heat exchanger model with the largest heat transfer surface and the smallest fan engines. The client, its engineering consultant, engineers and the experienced operating staff, heeded the presentation of our findings and arguments. The calculations have unequivocally shown the positive and quick internal rate of return, up to a few months, even by the higher investment required for our condensers.
The equipment we have offered has the following advantages:
• Lower power consumption
• Greater condensing heat exchanger
• Smaller and more economical fan engines
• And lower maintenance and sustainability costs
The outcome
In the year 2000, four capable condensers of the above mentioned model were supplied by “Krashin-Shalev”. In 2006, two additional units were added by us. In 2018, on a regular visit of ours to the client, we were interested if the time has not come to replace the condensers with new ones. The client replied he had recently made some cosmetic improvements to the condenser, had changed some bearings and is intending to use the equipment for many more years to come (!). Here it is also important to note the excellent level of maintenance in this food processing facility: the investment in the supply of clean feed water; the regular periodic treatments according to ours and Evapco’s instructions; the wise usage of the equipment; the preventive maintenance - instead of “failure maintenance” – all those, on the fundament of our solution embodies by that equipment, have guaranteed such a long life span for this critical equipment, and it’s still going strong.
Pictured: Evaporative condensers.
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