Abstract: A support ring for accommodating a plate-like element in a vessel includes a bracket disposed on a wall of the vessel and configured to support the plate-like element, the bracket having an upper supporting surface inclined downward relative to horizontal.

Abstract: A process for a combustion of sulfur with an oxygen-containing gas to produce sulfur dioxide. The process includes introducing the sulfur and the oxygen-containing gas to a furnace. The sulfur is evaporated and subsequently a portion of the sulfur is oxidized to sulfur dioxide under sub-stoichiometric conditions in a first portion of the furnace. The sulfur dioxide formed in the first furnace portion is introduced together with any unoxidized sulfur to a second portion of the furnace which is disposed adjacent to the first furnace portion. The sulfur dioxide and unoxidized sulfur are subjected to post-combustion with the oxygen-containing gas in an inlet of a downstream waste heat boiler.

Abstract: To protect a plate-type heat exchanger (1) against corrosion due to the attack of sulfuric acid, it is proposed in accordance with the invention that the region through which flows sulfuric acid has at least one metal cathode (16, 17) and one reference electrode (27), that at least half the metal plates (7) have an electric contact (23) which is connected with the anode (21) of an electric d.c. voltage source of variable electric voltage, that the metal cathode (16, 17) likewise is electrically connected with the d.c. voltage source, and that the d.c. voltage source belongs to a potentiostat (20) which is electrically connected with the reference electrode (27).

Abstract: To protect a plate-type heat exchanger (1) against corrosion due to the attack of sulfuric acid, it is proposed in accordance with the invention that the region through which flows sulfuric acid has at least one metal cathode (16, 17) and one reference electrode (27), that at least half the metal plates (7) have an electric contact (23) which is connected with the anode (21) of an electric d.c. voltage source of variable electric voltage, that the metal cathode (16, 17) likewise is electrically connected with the d.c. voltage source, and that the d.c. voltage source belongs to a potentiostat (20) which is electrically connected with the reference electrode (27).

Abstract: This invention relates to a method for the protection against corrosion of steel parts made of austenitic or semi-austenitic steel during the production of sulfuric acid. To improve the corrosion resistance of the steel parts which are in contact with the sulfuric acid, it is proposed to use austenitic or semi-austenitic steel which has a Cr content of 15 wt-% to 36 wt-% and an Ni content of 9 wt-% to 60 wt-% and in which the ratio of the chemical elements (Cr+Si)/(Ni+Mo) lies in the range from 0.9 to 1.9 or in which the ratio of the chemical elements Cr/(Ni+Mo) lies in the range from 0.8 to 1.5, and to additionally provide this steel part with an anodic corrosion protection.

Abstract: Ferritic chromium-molybdenum steels containing26 to 30% chromium1.8 to 3.0% molybdenum3.0 to 4.5% nickelcarbon.ltoreq.0.02%silicon.ltoreq.1.00%manganese.ltoreq.1.00%sulfur.ltoreq.0.015%carbon+nitrogen.ltoreq.0.045%niobium.gtoreq.12.times.%C.ltoreq.1.2%balance iron and impurities which are due to the melting technologyare used as corrosion-resisting material to make structural parts which are resistant to sulfuric acid in a concentration of and above 94% by weight and at a temperature up to the boiling point of the sulfuric acid.