FR2560367A1 - INDUSTRIAL REACTORS AND OVENS - Google Patents

Abstract

THE OBJECT OF THE INVENTION IS REACTORS AND INDUSTRIAL KILNS OF CYLINDRICAL OR SIMILAR SHAPE SUBJECT TO STRONG THERMAL STRESSES, CHARACTERIZED IN THAT THEY ARE CONSTRUCTED BY MEANS OF PRECAST CONCRETE ELEMENTS 1, 2, 3 WHICH ASSUME IN THE WIDEST MEASURES OR COMPLETELY THE FUNCTIONS OF STRENGTH AND STABILITY AS WELL AS THE TECHNICAL FUNCTIONS OF REACTORS AND INDUSTRIAL OVENS AND THE FUNCTIONS OF THE REFRACTORY COATING.

Description

i

  The present invention relates to reactions

  torers and industrial ovens subjected to thermal stresses, for example rotary tube ovens, drying drums, tubular pipes, tank ovens and smoke tanks.

  Industrial reactors and ovens of cy- form

  lindrique or the like, for example rotary tube ovens, drying drums and heat exchangers have been produced all over the world for decades by the assembly of tubular steel elements

  and constitute high-cost steel constructions.

  In addition, for the protection of steel construction and

  for reasons inherent in the processes applied therein

  These devices must have a refractory coating.

to hush up.

  The construction method adopted up to now for reactors and industrial furnaces has the following serious drawbacks: - their manufacture and their repair require the use of large quantities of quality steel, - the elasticity of the steel material causes deformations of the construction and, consequently, the destruction of the refractory lining,

  - the differences between the coefficients of dila-

  thermal rating of steel construction and coating

  refractory lining pose problems of stability and, consequently, cause walking incidents, the refractory lining requires manufacturing

  of special refractory bricks with a large number-

  bre of different formats, - the wear of the refractory lining imposes costly and complicated capping and repair work, - due to its high weight, the refractory lining requires additional constructions containing

  a lot of steel and foundations of corresponding importance

  laying, - the refractory lining does not have any interesting constructive properties as regards

the stability of the installation.

  The object of the invention is to allow, for the

  construction and operation of reactors and furnaces

  manufacturers subject to high thermal constraints, reduce installation costs, significantly improve operating safety and eliminate the disadvantages of

known construction methods.

  The object of the invention is therefore, for the construction of

  tion and operation of reactors and industrial furnaces

  subject to high thermal stresses, to reduce for-

  the proportion of steel used and to replace it

by better adapted materials.

  This object is achieved, according to the invention, because the industrial reactors and furnaces are constructed from precast concrete elements which constitute complete construction elements filling the

  solidity and stability conditions imposed and

  at the same time meeting the requirements arising from the processes applied in the apparatus and the requirements imposed on the refractory lining. The invention therefore makes it possible to produce reactors and industrial ovens in which the refractory nature of the coating, the requirements relating to

  stability and requirements arising from the processes applied

  that in the devices are ensured by the elements of

precast concrete.

  According to the invention, the problem is solved for example by the fact that the reactors and industrial furnaces are constituted by precast concrete elements which comprise several layers and are constituted by tubes comprising ribs, placed outside and provided with a frame, or an inner frame and which

  are securely connected to each other by an adapta-

  tion of their shapes and a solid interlocking while

can be dissociated.

  The advantages of the invention reside in the fact that the stability properties of the steel construction or of the steel shield and the properties of the refractory lining are associated in the construction. The following advantages result:

  the quantity of steel required for construction

  tion and repair of the corresponding installations is reduced to a minimum, - there are practically no more deformations, - the problems resulting from the. difference between the expansion coefficients of the steel shield and the refractory lining are eliminated,

  - the work of sealing the refractory lining -

shut up cracked are removed,

  - the manufacture of special refractory bricks

is no longer necessary,

  - repairs to reactors and ovens

  manufacturers produced according to the invention can be insured

  through modern processes such as, for example, the use of

  sprayed concrete or replacing elements of

individual concrete.

  The invention has still other advantages with regard to rotary tube ovens because the problems resulting from thermal expansion at the level of the shielding of the oven and the hoop are eliminated, that the problems of the heating regimes cease to exist. be

  essential because refractory concrete, in particular,

  puts a rapid rise in temperature, that the thermal insulation is significantly improved because it is possible to make the precast concrete elements in several layers using insulating concrete, and that there is no longer any question of deformation of the shielding of steel, with all the negative consequences that this deformation entailed

for refractory lining.

  The invention is described below in a way

  more detailed with reference to the drawing.

  The single figure represents an industrial oven

  cylindrical or similar in shape subject to strong

  thermal traces, for example a heat exchanger

  like those used in the cement industry.

  The precast concrete elements shown

  in fig. 1 are the lower part 1, the upper part

  including the wall 2 and the cover 3 which, for

  meet the conditions prevailing in the corresponding areas

  dantes, are made of refractory concrete and include a reinforcement

  inner structure 4 and a layer 5 of thermal insulation.

  The precast concrete elements are connected to each other, by adapting their shapes, in a leaktight and

  so that they can be separated.

  The advantages of the invention consist in that

  that, contrary to what characterized the mode of cons-

  previous construction, there is no longer any need for steel shielding, that the thermal insulation is improved, that there is no longer any break in a refractory lining, that there is no longer any need for bricks special refractories to achieve the coating, that repairs can be carried out by reloading concrete, using shotcrete or by replacing individual precast concrete elements and that damage to the coating due to differences in coefficient of thermal expansion between the shielding in

  steel and refractory lining are eliminated.

  Other possible embodiments allowing the application of the invention are tank ovens, rotary tube ovens and drying drums for which also the steel construction

  and steel shielding can be removed.

Claims (3)

  1. Cyt-shaped reactors and industrial furnaces   lindrique or the like subjected to strong thermal constraints   miques, characterized in that they are constructed by means of prefabricated concrete elements (1, 2, 3) which assume to the greatest extent or completely the functions   strength and stability as well as the technical functions   reactors and industrial furnaces and the functions refractory lining.   2. Reactors and industrial furnaces according to claim 1, characterized in that, preferably, the rotary tubular furnaces are constructed, in part or in whole, by means of precast concrete elements in one or more layers (5), provided a frame (4) and   having a layer of thermal insulation.   3. Reactors and industrial furnaces according to one of   claims 1 or 2, characterized in that the elements   prefabricated are connected to each other, by adaptation of their shape and tight interlocking, in a removable manner or solidly.