C-T Principles

Preface

This manual is projected for use by operators, erectors and service maintenance staff. This will help you in accurate installation, precise operation and easy maintenance of the Cooling Tower. The manual should be studied in a thorough way, and it helps maintain your Cooling Tower in good operating condition. There is a need of timely and appropriate preventive maintenance practice. Also, the operators will gain an understanding of cooling towers, codes of problems & methods for effective dealing.

_______________________________________

Introduction

A Cooling Tower is a heat exchanger with direct contact, commonly used to disperse the heat in circulating water. The heat dissipation is done via a process of heat & mass transfer, from the circulating water. Thus, the water cooled is circulated over through the process, condenser or heat exchanger. The transfer of heat to the water either in a condenser such as refrigeration / air-conditioning system, or chemical procedures / heat exchangers in the cooling process, engines, furnaces and generating sets etc.

Some of the key aspects of the cooling tower design:

• Perform to the requisite specification

• More compact & weigh less

• Consume minimum power

• Long lasting, resistant to corrosion and have good finish, looks.

________________________________________

Definition

A wet cooling tower is an encircled system used to dispose waste heat through evaporation from the industrial processes, refrigeration or air-conditioning system etc. It operates on the direct contact of the most common substances: Air and Water.

________________________________________

Principle of Operation

Automatic rotating sprinkler system is there to distribute the hot water consistently over the complete fill section. At the same time, dry air is drafted upward producing evaporation. The cooled water falls into basin, and pumped to the source of heat for recirculation.

________________________________________

Terminology

It is essential to define the common terms of cooling tower operation:

Approach is the difference between the outlet cold water temperature and wet bulb temperature of the incoming air. For 35°C water outlet and 27°C wet bulb, the approach is 8°C.

Rate of circulating water is the amount of hot water entering the tower.

Placed within the tower, Fills influence heat and mass transfer between the circulating water and air flowing through the tower.

Casing is vertical surrounding sidewall, which surrounds the fills as well as maintains the water within the tower.

Distribution system comprises the inlet connection for circulation of the hot water within the tower, where it comes in contact with air.

Eliminator is an assembly that removes entrained moisture from discharged air.

________________________________________

Better Air Flow

There is no need of conventional type moisture eliminator; the rotating water sprinkler head effectively distributes the hot water within a fine spray. It’s because the water header has a large number of holes to give a steam type flow directly into the infill. The towers with fixed nozzles cannot achieve the coverage, required for optimum cooling. There is no need to overlook that in rectangular type towers, the eliminators deliver a pressure drop which evens out the flow accuracy into the corner. The round advance tower with its conical fan inlet better provides the even air flow through the infill, along with a lower pressure drop and without extra pressure drop produced by the eliminator required on other towers. KW of Fan depends on the mass of air distributed, the pressure created and blade efficiency. Advance air capacities are similar to competitor's sizes. The key factor for lower power is 'pressure' & 'efficiency'.

The "Advance" tower features:

• Large air inlet area, low air velocity & low pressure drop
• Induced draft type.
• Ideal fan position to discharge the air at high velocity and for effective convection to prevent recirculation.

________________________________________

Pumping Head

As we have seen already that the water distribution by a rotating header is a major part of the Advance tower design. Large diameter holes in the rotating header provide a gentle water stream at negligible pressure loss. And there is no risk of clogging as in other types of towers. It should be kept in mind that the pumping heads for Advance towers comprise both of these and the piping in the sprays pressure loss. The static lift must be added to the spray header from the elementary water level, as well as the outside piping friction loss. In several cases, the pumping head is necessary for an Advance tower - about 50% less than other towers.

________________________________________

Life Factor

The towers are constructed of FRP (Fiberglass Reinforced Plastic), and it should not be mixed up with translucent fiberglass panels. A suitable protective layer should be there to prevent the ultra violet rays. The Advance tower casings have a protecting Neopently Glycol gel coat to resists the sun's rays. Thus, the Advance towers do not require painting. As compared with timber towers which eventually rot, or steel towers which rust despite the improved maintenance, the fiberglass tower offers a great financial advantage. Unfortunately, a lot of buyers only concerned to maintenance, rate of deterioration or running costs.

________________________________________

Smaller Fan Motors

Motor with lower HP rating is used in Advance towers, thus it leads to a considerable saving in energy cost. The Advance, High Performance FRP Cooling Towers are designed for longer life and lower maintenance. With these you can save money on maintenance and electricity bills, making the ADVANCE a perfect Cooling Tower.

Key aspects of the ADVANCE Cooling Towers:

• Greater laminate strength, reduced vibration and increased tower life.
• Effective UV protection & color retention with better surface finish.
• Secondary drain tank in corrosion resistant FRP.
• Fans, sprinklers & hubs in gravity die cast aluminum.
• Smoother operation with longer bearing & motor life.
• Graded PVC fills.
• Power saving leads for lower electric bills with direct drive motors.
• Protection against faulty parts including Motor.