Split feed economizer

Claim 2

In a shell-and-tube heat exchanger for the generation of vapor by the indirect transfer of heat from a heating fluid to a vaporizable liquid including a pressure vessel enclosing a bundle of heat exchange tubes and defining a vapor generating chamber, means for circulating heating fluid through said tubes, and means for supplying vaporizable liquid to said vapor generating chamber, the improvement comprising: a. plate means defining a compartment enclosing a portion of the heat transfer surface of said tubes and dividing said vapor generating chamber into an economizer section and an evaporator section; b. means defining openings at oppositely spaced ends of said compartment for discharging preheated liquid to said evaporator section; c. means within said compartment dividing the same into two fluidly distinct sections each communicating with one of said openings; and d. means for supplying vaporizable liquid to each of said compartment sections.

Claim 3

The improvement as recited in claim 1 wherein said vaporizable liquid supply means comprises individual feedwater nozzles communicating with each of said compartment sections.

Claim 4

The improvement as recited in claim 2 including separate lines connecting each of said feedwater nozzles to a source of vaporizable liquid, and means in said lines for independently regulating the flow of liquiD through each.

Claim 5

The improvement as recited in claim 1 wherein said compartment includes a plurality of baffle plate members for directing each part of said vaporizable liquid in generally cross flow relation to the tubes extending through said compartment.

Claim 6

The improvement as recited in claim 1 wherein said tubes are disposed in generally parallel relation and conduct said heating fluid in similar directions through said compartment in substantial countercurrent relation to one of said parts of vaporizable liquid and substantial cocurrent relation to the other of said parts.

Claim 7

The improvement as recited in claim 2 wherein said divider means comprises a transverse plate dividing said compartment into two longitudinally spaced sections.

Claim 8

A shell-and-tube heat exchanger for the generation of vapor by the indirect transfer of heat from a heating fluid to a vaporizable liquid comprising: a. a generally vertically elongated cylindrical shell; b. transversely extending tube sheet means dividing the interior of said shell into a vapor generating chamber and heating fluid chamber means; c. a bundle of heat exchange tubes extending through said vapor generating chamber and having their ends attaching said tube sheet means in communication with said heating fluid chamber means for circulating heating fluid through said tubes; d. means for supplying vaporizable liquid to said vapor generating chamber; e. means for preheating said vaporizable liquid including: i. a plurality of plates defining a longitudinally extending compartment disposed within said vapor generating chamber and defining evaporator and economizer sections therein; ii. means defining openings adjacent the oppositely spaced ends of said compartment for discharging preheated liquid to said evaporator section; iii. means within said compartment dividing the same into two fluidly distinct sections each communicating with one of said openings; and iv. said vaporizable liquid supply means connecting with each of said compartment sections.

Claim 9

A shell-and-tube heat exchanger for the generation of vapor by the indirect transfer of heat from a heating fluid to a vaporizable liquid comprising: a. a generally vertically elongated cylindrical shell; b. transversely extending tube sheet means dividing the interior of said shell into a vapor generating chamber and heating fluid chamber means; c. a bundle of heat exchange tubes extending through said vapor generating chamber and having their ends attaching said tube sheet means in communication with said heating fluid chamber means for circulating heating fluid through said tubes; d. means for supplying vaporizable liquid to said vapor generating chamber; e. means for preheating said vaporizable liquid including: i. a plurality of plates defining a longitudinally extending compartment disposed within said vapor generating chamber and defining evaporator and economizer sections therein; ii. means defining openings adjacent the oppositely spaced ends of said compartment for discharging preheated liquid to said evaporator section; iii. means within said compartment dividing the same into two fluidly distinct sections each communicating with one of said openings; and iv. said vaporizable liquid supply means connecting with each of said compartment sections.

Claim 10

A heat exchanger as recited in claim 7 wherein said compartment is defined by plate members enclosing a portion of said tube bundle.

Claim 11

A heat exchanger as recited in claim 8 wherein said compartment is disposed in spaced apart relation to the interior surface of said shell-and-tube sheet to define passage means for conducting heated liquid.

Claim 12

A heat exchanger as recited in claim 9 wherein said tube bundle comprises a plurality of vertically extending, generally U-shaped tubes and including a downcomer baffle surrounding said tubes in concentrically spaced relation to the internal surface of said shell to define an annular downcomer passage.

Claim 13

A heat exchanger as recited in claim 10 wherein said compartment is defined about its outerperiphery by a portion of the lower end of said downcomer baffle and about its inner periphery by a vertically extending planar plate whose end edges attach the inner surface of said downcomer baffle.

Claim 14

A heat exchanger as recited in claim 11 wherein said divider means comprises a transverse plate disposed within said compartment intermediate the ends thereof to define two longitudinally spaced sections, said transverse plate being sealingly attached about its peripheral edge to said downcomer baffle and said planar plate.

Claim 15

A heat exchanger as recited in claim 12 wherein said vaporizable liquid supply means comprises individual feedwater nozzles communicating with each of said compartment sections.

Claim 16

A heat exchanger as recited in claim 13 including separate lines connecting each of said feedwater nozzles to a source of vaporizable liquid, and valve means in said lines for regulating the flow of liquid through each.

Claim 17

A heat exchanger as recited in claim 11 wherein said compartment includes a plurality of vertically spaced, transversely extending baffle plate members for directing each of the parts of the flow of vaporizable liquid in generally crossflow relAtion to the tubes extending through said compartment.

Claim 18

A heat exchanger as recited in claim 11 including transversely extending plates defining the upper and lower ends of said compartment, said plates containing means defining openings for establishing fluid communication between the interior of said compartment and the adjacent region of said evaporator section.

Claim 19

A heat exchanger as recited in claim 16 wherein the liquid discharged from said compartment to said evaporator section is at about saturation temperature.

Claim 20

A heat exchanger as recited in claim 17 wherein the lower end of said downcomer baffle is vertically spaced from the adjacent tube sheet and the lower end of said downcomer passage is in open fluid communication with said evaporator section adjacent the lower end of said compartment.