Placement of nozzles in process equipment

By Pramod Dixit

Type of process equipment

• Columns• Heat exchangers• Air fin coolers• Tanks• Vessels• Separators• Bullets and spheres

Understanding tray geometry(most of the time controversy arises in columns being complex)

Nozzle Types

• Process nozzles

• Instrumentation nozzles

• Utility connections

• Safety connections ( safety valves, rupture disc)

• Man-holes and hand holes

Process Nozzles

• Feed• Intermediate Liquid or Vapor or Mixed feed• Reboiler liquid outlet • Reboiler vapor inlet• Reflux inlet• Product outlet• Sampling connection

Maintenance & Utility Nozzles

• Manhole• Hand hole• Drain• Steam • Nitrogen

Instrument Nozzles

• Level Gauge• Level controller• Temperature Gauge / transmitter• Pressure Gauge/ transmitter• Differential pressure recorders/ transmitter• Level switch• Safety valve

PG / TG connections

Thermowell

Thermowell

Pressure gauge

Thermowell to be in liquid

.Pressure

measuring nozzle in vapor

phase always

Placement of PG & Thermowell

Thermowell preferred, in

down comer 4” above the tray

Pressure gauge, 6” to 8”

below the tray

Alternate thermowell 2”

above tray plate

Feed inlet devices #1

Mix feed or vapor feed

Feed inlet devices (shoepetentor)

Partial liquid withdrawal

Partial liquid withdrawal nozzle to be

flush with pan plate

Seal Pan

Draw off pan

Intermediate Liquid feed for high delta “T” case

Insulating plate for avoiding

temperature shocks

Bottom levels

LT

LG

Vapor in

Partial withdrawal from a chimney tray

Partial draw off nozzle Manhole to see

that man can enter in the

column

Reboiler return to column(preferably to be parallel to seal pan)

Both are Wrong way

Right way

Vapor stream

should not directly hit

the seal pan

Reboiler return to column

Prefer Vapor inlet parallel to seal pan

Type of mistakes in nozzle placement

• Reboiler out and product out interchanged• Themowell clashing with down comer• Thermowell not in liquid phase.• Level instrument wrong placement.• Feed to reboiler pan wrongly oriented.• Demister below safety valve.• Liquid draw off not getting liquid.• Not able to enter thru manhole.

Manhole & hand hole

Hand holesOne at top of

packed bed for filling the packing

Other at lower level for packing removal

Manhole ( a suggested spacing

900mm min for man to enter)

Placement of demister

ManholeSize

min18”

Multi layer distributor

Such distributors need larger head room for a

man to work in side based on the design

Nozzle close to Demister

Small vertical vessels

Level instruments to clear the legs

JET MIXER in Tank

Jet nozzles

Swirl type jet mixer

Side entry mixer for Tank

CFD of mixer

Recommended orientation of mixers

Mounded bullet outlet

LPG outlet nozzle

Fire proofing & water spray on bullet dome

Nozzles on Bullet Dome

Fireproofing on Bullet Dome

3 Phase separator

Cut section of 3 phase separator

Setting of level instruments in 3 phase separator

HH water

H igh water HHL OilNLL water NLL oil

Low waterLL oil

Low low waterLLL oil

Vessel shell

Set points of level switches

Range for ILG & ILT

Range for LG & LT

Weir