Cooling counter-flow

Barometric condensers are direct contact coolers and condensers. They may be counter flow or parallel flow. Good contact direct cooling is an efficient inexpensive design, being considerably cheaper and more efficient than indirect surface or tubular coolers. 

Counter-flow Cooling Tower Performance, J. F. Pritchard Co. of California (Pritchard Corp. is a Black and Veatch Co.) (1957). 

Paper refers to the contents of the title paper in Vol. 25, N. 5, of May 1972, and presents an empirical analysis of a number of carefully conducted tests in cooling towers of the vertical, counter-flow type. In order to put cooling tower performance on a common basis the area to height factor is introduced. Parameters examined by Dr. Whillier are reexamined and use is made of the area to height factor to predict cooling tower performance. 

Counter-Flow Evaporative Cooling Tower Performance Modeling and Verification... 

Evaluation of Counter-Flow Cooling Tower Cell Performance Wrinkle, R. B. 

Typically, TSOFC use co- and counter-flow configurations whereas planar stacks sometimes favour cross flow simplifying manifolds attachment. The flow of air usually provides cooling to a stack in either design as does internal reforming (Sulzer Hexis). The flow regime strongly affects the distribution of gas composition, mechanical stress, stack temperature and ultimately current density. 

Fig. 9.5. Acid cooler, courtesy Chemetics www.chemetics.com Cool water flows through 1610 internal 2 cm diameter tubes while warm acid flows counter currently (and turbulently) between the tubes. The tubes are 316L stainless steel. They are resistant to water-side corrosion. They are electrochemically passivated against acid-side corrosion by continuously applying an electrical potential between the tubes and several electrically isolated metal rods. Details shell diameter 1.65 m shell material 304L stainless steel acid flow 2000 m3/hour water flow 2900 m3/hour acid temperature drop 40 K. (Green pipes = water metallic pipes = acid.) Fig. 24.6 gives an internal view.

The mixture of gas and carbon black leaving the reactor is cooled to temperatures of 250-350 °C in heat exchangers by counter flowing combustion air and then conducted into the collecting system. 

SOLUTION Hot oil is cooled by water in a douhle-tube counter-flow heat exchanger. The overall heal transfer coefficient is to be determined. Assqmptions 1 The thermal resistance of the inner tube is negligible since the tube rhaterial is highly conductive and its thickness is negligible. 2 Both the oil and water flow are fully developed. 3 Properties of the oil and water are constant. 

A double-pipe counter-flow heat exchanger is to cool ethylene glycol (cp = 2560 J/kg °C) flowing at a rate of 3.5 kg/s from 80 C to 40°C by water (c, = 4180 J/kg C) that enters at 20°C and leaves at 55 C. The overall heat transfer coefficient based on the inner surface area of the lube is 250 V/m "C. Determine (o) the rate of heat transfer, (A) the mass flow rate of water, and (c) the heat transfer surface area on the inner side of the tube. 

The water cooled tubular reactor (WCTR) represents the optimal solution for the etherification because it is the best compromise between kinetics and thermodynamics [7]. The Snamprogetti (now Saipem) WCTR (Figure 11.5) is a bundle-type heat exchanger with the catalyst in the tube side and the tempered cooling water flowing co-current or counter-current in the shell side. The catalyst is self-supporting in the bottom shell of the reactor, in the tubes and above the upper tube sheet. 

A counter-flow heat exchanger is utilized to cool a 2.5 kg/s gas flow from 150 °C to 100 C by means of a 3 kg/s air flow which enters the exchanger at 10 °C. We wish to increase the size of this exchanger and cool the gas to 90 C rather than 100 °C. Assume that the other conditions remain the same, and determine.the ratio of heat transfer areas for the two cases. What is your conclusion ... 

COUNTER-FLOW HEAT EXCHANGER - When the fluid to be cooled flows against the direction of the coolant. In heat exchange between two fluids, opposite direction of flow, coldest portion of one meeting coldest portion of the other. 

The HCIHX for the HTTP is a vertical helically-coiled counter flow type heat exchanger in which the primary helium gas flows on the shell side and the secondary in the tube side as shown in Fig.2. The major specification is shown in Table 1. The primary helium gas of the maximum 950°C enters the HCIHX through the inner tube In the primary concentric hot gas duct. It is deflected under a hot header and discharged around the heat transfer tubes to transfer primary heat to the secondary cooling system. It flows to the primary circulator via an upper outlet nozzle and returns between the inner and outer shell in order to cool the outer shell. 

The performance of a PSR will be bench marked against two reference cases (i) a multi-tubular cooled plug flow reactor (PFR) containing only a catalyst and cooled co- or counter currently, and (ii) a combination of a PSA vessel containing a sorbent to separate A, and a multi-tubular cooled PFR containing a catalyst and receiving the A-enriched feed from the PSA. 

There have been many methods used for cooling infrared cells. Among these are Joule-Thomson cryostats. They utilize a high pres sure gas, a Joule-Thomson nozzle, and a heat exchanger to provide regenerative counter flow which cools the input gas so that a certain percentage of the gas is liquefied at the end of the cryostat. This device is mounted inside of a small dewar in which the detection cell itself is mounted. 

JSFR-1500 (Japan) straight tube, counter flow, prim. cool, in tubes... 

Scheme 3.13b) An oven-dried Schlenk tube equipped with a Teflon valve was charged with a magnetic stir bar, Cul (0.05 mmol, 10 mol%), CS2CO3 (1.1 mmol), 2-halophenol (0.60 mmol), 2-haloamides (0.50 mmol), and 1,10-phenanthroline (0.10 mmol, 20 mol%). The tube was evacuated and backfilled with N2 (this procedure was repeated 3 times). Under a counter-flow of N2,1,4-dioxane (2.0 mL) was added by syringe and the mixture was stirred for about 24 h at 90 °C. The reaction mixture was cooled to room temperature, ethyl acetate (20 mL) was added, and the resulting suspension was filtered. The filtrate was concentrated, and the residue was purified by column chromatography on silica gel (PE-EtOAc, 10 1-2 1, v/v) to provide the desired product. 

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