INSTALLATION OF S-50 AMMONIA

CONVERTOR

Prem Baboo

Sr.Manager (Prod)

National fertilizers Ltd. India

S-50 AMMONIA SYNTHESIS CONVERTER (R-3502)

Supplier: M/s MANGIAROTTI SpA

Transporter (Kandla port to NFL Vijaipur) : M/s Reshamsingh & Co Pvt Ltd., Mumbai

Operating conditions

Inlet Gas

Temperature oC 372

Pressure Kg/cm2 183.2

Total flow Nm3/hr 615,133

Composition

H2 Vol% 50.50

N2 Vol% 16.84

Inerts, CH4 + Ar Vol% 13.50

NH3 Vol% 19.16

Outlet Gas

Temperature oC 417

Pressure Kg/cm2 182.7

Total flow Nm3/hr 596,242

Composition

H2 Vol% 47.35

N2 Vol% 15.78

Inerts, CH4 + Ar Vol% 13.93

NH3 Vol% 22.94

Catalyst

Type KM1

Size mm 1.5-3

Diameters, OD (effective)/ ID mm 2,896 / 760

Height (excl./incl. bottom cone m 20,100 / 21,200

Volume m3 125,4

Mechanical Data (Pressure Vessel)

Type Vessel with top manhole

Inner diameter mm 3,000

Inner length (T-T) mm 20,250

Normal operating pressure Kg/cm2 g 183.1

Design pressure Kg/cm2 g 245

Hydrogen partial pressure, design Kg/cm2 130

Temperature of Operating Design

Cover and cylinder part oC 372 430

Spherical bottom oC 372 430

Bottom forging oC 419 450

Bottom flange oC 419 450

Nozzle sizes

Main inlet inch 16

outlet inch 16

Installation of S-50 ammonia synthesis

converter along with waste heat boiler in

downstream of existing S-200 ammonia

synthesis converter is one of the major

scheme of Capacity Enhancement Project of

Ammonia-II plant.

Pre shutdown activity

The anchor bolts were position with the help of template during casting of top portion of

foundation of S-50 ammonia synthesis converter and the same was grouted with Shrinkom-

20 after completion of civil work and removal of template. Top surface of foundation was

prepared for placement of equipment.

First of all skirt were placed on foundation and leveled at elevation of 106.200 mtr. with the

help of MS plats and gaps between base plate of skirt and civil foundation was filled by

Shrinkom-20.

After placement of skirt, S-50 ammonia synthesis converter was placed and leveled /

centered on skirt with the help of Demag CC2800-1and CC2000 crane on 12.08.2011.

Erection plan submitted by M/s Sarens Heavy Lift India Pvt. Ltd., party engaged by piping &

equipment erection contractor (M/s Satnam Global Infraprojects Ltd., Delhi) for heavy

equipment erection alongwith cranes is enclosed.

After opening of top cover and outer screen panel covers, joint inspection was done by NFL /

HTAS to check any damage during transportation / erection and found Ok. Lot of rust as

scale was found on inside surface of reactor which was vacuum cleaned before catalyst

loading.

Catalyst was charged with the help of shower head from 31.01.2012 to 06.02.2012 by M/s

Amol Construction in presence of HTAS representative Mr. AsadRadfar. The approximate

density of catalyst achieved was 2.95 Kg/litre. During charging of catalyst, support

provided for centre screen and outer screen panels were removed which was provided by

the supplier to avoid any damage while transit.

After catalyst loading, outer screen panel cover boxed up and tack weld as instructed by

HTAS. Gland packing of stuffing box (centre screen and outer screen panel cover flange)

checked and found OK. Top cover and bottom cover were boxed up with the help of bolt

tightening device and lip seal welded with Inconel filler wire.

Insulation job of S-50 Ammonia synthesis converter (160.0 mm thick) and connecting pipe

line job done by M/s Kaefer Punj Lloyd Limited.

Shutdown Activity:

All the prefabricated pipelines were hydrotest at 367.5 Kg/cm2 before hookup with existing

header and S-50 converter. RT of the all weld joint done on half weld and UT at full weld joint

of pipe line. Stress reliving of alloy steel pipe weld joint (2.25Cr 1Mo steel) was done as per

ASME section and Hardness was achieved below 220 HB. Instrumentation, Electrical and

Structure job were taken care by respective department.

*****************************************************************