Cooling Tower Optimization

The plant s demand for cooling water (CW) is variable, and meeting that load with constant-speed pumps is wasteful. When the demand for CW drops, the airflow can also be reduced. In optimized CTs both the water and the airflows are controlled by variable-speed devices. The goal of CT optimization is to maximize the amount of heat discharged into the atmosphere per unit of operating cost invested. 

As the CT approach increases, and therefore Tctws rises, the temperature difference across the process cooler (T1 -Tctws) is reduced. This will cause the process temperature (T) to rise and its controller (TIC-4) to further open 

Optimization minimizes the unit cost of cooling by minimizing the operating speeds of both the cooling tower fans and pumps. 

TDIC-2 is the range controller, which is set by the optimized set point of SP-2. This is the range value corresponding to the optimum approach. TDIC-2 throttles the water circulation rate and sets the speed of the CT water circulating pumps in such a way that none of the process user valves (CV-4) will be fully open. This is guaranteed by the cascade loop of PDIC-3 and valve position controller (VPC-4). 

In larger power plants, a number of CT cells are used to cool the returning cooling water, and part of the optimization strategy is to fully utilize their 

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Provides abstracts of worldwide research on design and performance of mechanical draft and natural draft wet, dry, and dry-wet combination cooling towers. Abstracts cover studies on size reduction, corrosion protection, and economic optimization of cooling towers primarily used with nuclear power plants and fossil fuel power plants. Also covered are abstracts which pertain to cooling towers used in waste-water treatment. It contains 305 abstracts, 65 of which are new entries to the previous edition. 

A method is given for predicting the costs of large evaporative type natural and mechanical draft cooling towers as functions of the main design parameters. The costs and parameter factors are expressed analytically for use in power plant optimization programs. 3 refs, cited. 

Energy Optimization of Cooling Tower Blowdown Recovery Ahlgren, R. M. 

Extraction of potable water from saline waters by means of immiscible solvents has been shown to be theoretically possible, experimentally feasible, and economically attractive. Data presented show the process to be especially adaptable to the conversion of feed water in the range of 5000 to 10,000 p.p.m. It is adaptable to use of low-quality heat such as hot water from cooling towers or low pressure waste steam. By use of mixed solvent systems, the process can be optimized to take advantage of seasonal changes in temperature and sources of cold feed water and low-level heat sources. The process, in general, is somewhat more economical when a cold source of feed water is available. 

The proportion of Ml increases in warm weather regions. M2 and M4 increase when water transport lines are long and the proportion of M3 is lowered as the maximum allowable chilled water temperature rises. However, regardless of these proportions in a particular installation, the goal of optimization is to find the minimum chilled water and cooling tower water temperatures that will minimize the total cost of operation. 

In order to optimize a cooling system, the cooling towers, pumping stations, chillers, and process equipment should be treated as an integrated single system. 

The cooling water used in most chillers is received from cooling towers (CTs) and as was shown in Figure 2.11, chillers and CTs are optimized as a single... 

The optimization of renewable energy processes, when applied to building conditioning, dryer, boiler, and cooling tower processes, necessitates the... 

The plan takes an overall consideration of heat damage control and waste heat utilization in Zhu-jixi Coal Mine, which optimizes the systems, uses complex facilities, shares the softened water treatment system and gives an overall consideration of cooling tower equipment and pipeline layout. 

Despite this concern, some users of Ciass II cosolvent machines do not use chilled brine. Obviously, these users will experience reduced energy costs and required investment, and also experience increased costs of solvent loss. Certainly, chilled brine is not required for effective cleaning. In Table 1.5 is tabulated a comparison of cooling tower performance vs. that of mechanical refrigeration of "brine." The choice between chilled brine and cooling tower water is simply one of optimization. 

For the large cooling towers built in the last few decades, the thin reinforced Crete shell, reinforced in two axes on both surfaces, has proved eminently suitatable. For structural, thermodynamic and flow optimization reasons rota-tionally hyperbolic shapes are desirable, and occasionally also cylinders. These shapes are at same time aesthetically pleasing because they make the gigantic dimensions of the structures seem tolerable. 

Figure 3.13. Crude oil vacuum tower. Pumparound reflux is provided at three lower positions as well as at the top, with the object of optimizing the diameter of the tower. Cooling of the side streams is part of the heat recovery system of the entire crude oil distillation plant. The cooling water and the steam for stripping and to the vacuum ejector are on hand control.

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