Knowledge for the Sulphuric Acid Industry

Introduction
General
Definitions
Instrumentation
Plant Safety
Metallurgial Processes
Metallurgical
Sulphur Burning
Acid Regeneration
Lead Chamber
Technology
Gas Cleaning
Contact
Strong Acid
Acid Storage
Loading/Unloading
Transportation
Sulphur Systems
Liquid SO₂
Boiler Feed Water
Steam Systems
Cooling Water
Effluent Treatment
Utilities
Construction
Maintenance
Inspection
Analytical Procedures
Materials of Construction
Corrosion
Properties
Vendor Data

Google Search

Contact Section - Stacks - Erection
January 18, 2003

Introduction

The following sequnce of pictures illustrates the lifting and erection of an acid plant stack.

	Lifting of any large piece of equipment is a dangerous operation.  Countless things can go wrong if the lift is not planned and executed properly.  An acid plant stack is often the first major piece of equipment to be erected since this provide better access for the large cranes required. A stack lift is not a heavy lift but its length does make it an event to be watched.
	In this case three cranes are used to perform the lift.  One crane is use at the base of the stack to lift and guide the bottom.   Two cranes are used at the top of the stack the perform the lift.  A frame work is used in the inside of the stack to attach the liftng cables.   This ensure that the top of the stack is not damaged during the lift. Generally, as much of the platforms and ladders are attched to the stack while it is still on the ground since it is easier and safer to perform the work on the ground than after the stack is erected.
	The stack must be design properly so the no damage to the stack occurs when it is first lifted.  Normally, a stack is subjected to wind loads, earthquake loads, etc.  When a stack is first lifted from the horizontal position there is a risk that the stack will buckle in the middle.  The walls of the stack must be thick enough to prevent this buckling.  Reinforcing rings are also utilized to ensue that the stack does not buckle.
	As the stack comes to the vertical position the crane at the bottom must guide the base of the stack to its foundation.
	During this lift workers were stationed at the top of the stack.  This is not normal practice and posses a risk to the workers.   Eventually workers will be required at the top of the stack to release the lifting cable and remove the lifting frame.
	The stack is finally lifted in the vertical position and is guided on to the foundation. The cranes will remain attached to the stack until the base of the stack is secured to the foundation.

Copyright© 2005-2009 DKL Engineering, Inc., All Rights Reserved
DKL Engineering, Inc. shall not be held liable for any type of damages resulting from the use of this information. The user assumes all risk and liability in connection with the use of information contained in this and associated web sites.  The data is intended for personal, non-commercial use.