AL-AMIRI, Abdalla Mohamed (P.O. Box, Al-Ain, 17555, AE)
AL-AMIRI, Abdalla Mohamed (P.O. Box, Al-Ain, 17555, AE)
| CLAIMS
- LOTOCH is a cold water generation system which has set of components arranged in a manner to work under two distinct operational configurations (single and dual loops).
- The basic innovative operational configuration is when all components are connected in series in a single loop following the sequence CT 5 EV, LP, CC, CD, TP and back to CT as shown in Fig.4.
- The assistant operational mode is when the system has dual loops, similar to a classical chiller system; one between EV, LP and CC and the other between CD, TP and CT as shown in Fig. 3. - LOTOCH automatically alternates between the two operational configurations to suit the incurred ambient condition and cooling load.
- The system is used for cooling inlet air of the combustion turbines.
- The system is used as an auxiliary cooling system with the cooling tower applications to adjust the tower supply water. Not clear.
- The system is used for cooling the outside air in the ventilation applications. |
Free Cooling Scheme for Process Cooling and Air Conditioning Applications
Technical Field
This invention relates to cooling system for process cooling and air conditioning applications.
Background Art
A classical chilled water system as illustrated in (Fig. 1) consists of CH 5 CT, LP, TP interconnecting piping and controls. The system is characterized with two separate water loops; one links EV, LP and CC while the second links CD, TP and CT. The EV captures heat from CC and rejects it along with the energy added to the cycle from CM through CD by means of an open loop CT. One method to reduce the energy consumption of CH is to employ what is conventionally known as 'free-cooling' in the air conditioning applications as illustrated in (Fig. 2). Free cooling is a direct removal of heat load by tower cold water without running CH. In free- cooling operation, CT picks the entire cooling load through a bypass arrangement whenever the ambient wet bulb temperature allows CT supply water temperature to dip below the required temperature for the inlet water to CC. In such a case, HE transfers heat between the contaminated CT water and clean EV water without mixing the two circuits. This mode reduces the duration of CH operation and saves its energy.
The cooling system alternates the water circulation path between one of two modes as follow:
Free-cooling mode: CT solely and directly removes heat from CC and rejects it to the surrounding
Classical cooling mode: CH removes heat from CC and rejects it through CT to the surrounding
Defects Of The Existing Art
Free cooling is achieved only when CT supply water temperatures dip below the required cold water temperature for CC. Free-cooling is seized once the ambient wet bulb temperature is elevated to its threshold at which CT water
will not be cold enough to remove the heat load, then the system returns to its normal operation mode.
The conventional free cooling system has three main defects, which are:
Limited hours of operations even in dry weather condition in such a way that may not be practical nor feasible to offset the investment of the modifications
Does not provide any possibility for reducing CH size as such CH is always sized for the maximum cooling load
Limited range of cooling due to the extra heat transfer stage at the HE between the open type CT and EV water.
Disclosure of Invention
The Load-Tower-Chiller cooling scheme (LOTOCH) consists of CH, closed-loop CT, TP, LP and CC. LOTOCH has the capability to work under two distinct operational configurations by manipulating the interconnecting piping as follow:
Dual loop configuration: as illustrated in (Fig. 3), this arrangement has dual water circulation loops similar to the classical chilled water system. The control system opens Vl & V3 while closing V2 & V4 to establish dual loops such that EV, LP and CC are tied in one loop while CD, TP and CT in the other loop.
Single loop configuration: as illustrated in (Fig. 4) in which all system components are connected in series in a single loop. The control system opens V2 & V4 and closes Vl & V3 allowing same water to circulate amongst all chiller system components following the sequence CT, EV, LP, CC, CD, TP and back to CT. This is the basic configuration of LOTOCH while the dual loop configuration is a special case for certain ambient conditions.
LOTOCH has the following three modes of operation:
All-Tower (ALT) cooling mode: this mode is applicable when the ambient condition is dry enough so that the temperature of the produced cold water from CT is equal or lower than that is required at CC inlet. In this mode, CT will be able to directly and solely remove the heat load without running CH as such saves its energy. This mode represents another form of the conventional free cooling concept.
All-chiller (ALC) cooling mode: this mode is applicable when the ambient condition is humid to the level that the water delivered from CT is not cold
enough to remove any heat from CC. Then, CH will be solely responsible to remove all heat from CC and rejects it through CT. This mode is similar to the classical cooling system
Tower and chiller cooling (TAC) mode: when cooling is required while the ambient condition is anywhere between the above two mentioned cases, both CT and CH will work together in series in the single loop arrangement. The CT works as a prime source of cooling to deliver the coldest possible supply water at the incurred ambient wet bulb temperature. Temperature of supply water will be cold enough to the extent that it will remove the heat load partly, but yet higher than that required for CC inlet. CH will then serve as a secondary source of cooling which will further cool down the supply water to the temperature required for CC. In such a scenario, a part of the heat load is removed by CT at lower energy consumption while the rest is removed by CH. The part of heat load removed by CH depends on the desired water temperature at CC and the incurred ambient wet bulb temperature. The CH size may also be reduced significantly with the above conditions.
Brief Description of the Drawings
CH Water-Cooled Chiller
CT Cooling Tower
CC Cooling Coil
CD Condenser
EV Evaporator
CM Compressor
TP Tower Pump
LP Load Pump
HE Heat Exchanger
Vx Valve Number
ALT All-Tower Cooling
ALC All-Chiller Cooling
TAC Tower and Chiller Cooling
Next Patent: METHOD FOR THE INSTANTIZATION OF POWDERS, PARTICULARLY OF COCONUT MILK POWDER