Patent GB-199004-A (GB)
Title: Method and apparatus for automatic regulation of the supply of oxidising agents, nitric acid, nitrate solution or ethers in the manufacture of sulphuric acid
IPC: C01B17/84
Filed: 1923-05-11
Abstract: The rate at which the oxidizing agent is fed to the reaction in the production of sulphuric acid in chamber, tower, or like apparatus is controlled by the difference of temperature between the gases when leaving and when entering the plant, or the difference between the temperatures of the first and last chambers or towers.  The temperatures are measured by electrical thermometers which are connected through suitable resistances with a galvanometer and battery in the manner of a Wheatstone bridge arrangement so that the difference of temperature is measured by the galvanometer deflection. The zero of the galvanometer scale is arranged to indicate the desired difference of temperature, and two adjustable contacts are arranged on the scale on either side of the zero so that the pointer of the galvanometer on reaching these contacts will make or break a circuit controlling the cock which admits the oxidizing agent, the distance of the contacts from the zero corresponding with the permissible fluctuation of the temperature difference.  It is stated that this controlling apparatus may be connected with more than one apparatus for admitting the oxidizing agents, for instance, in such a way that these are controlled simultaneously or one after the other; or it may be arranged to control two or more admission apparatus for two or more first chambers; or it may control only a part of the total supply of oxidizing agent, the rest being admitted by an apparatus not automatically controlled.ALSO:The rate at which the oxidizing agent is fed to the reaction in the production of sulphuric acid in chamber, tower or like apparatus is controlled by the difference of temperature between the gases when leaving and when entering the plant, or the difference between the temperatures of the first and last chambers or towers.  These temperatures are measured by electrical thermometers which are connected through suitable resistances with a galvanometer and battery in the manner of a Wheatstone bridge arrangement so that the difference of temperature is measured by the galvanometer deflection.  The zero of the galvanometer scale is arranged to indicate the desired difference of temperature, and two adjustable contacts are arranged on the scale on either side of the zero so that the pointer of the galvanometer on reaching these contacts will make or break a circuit controlling the cock which admits the oxidizing agent, the distance of the contacts from the zero corresponding with the permissible fluctuation of the temperature difference.  It is stated that this controlling apparatus may be connected with more than one apparatus for admitting the oxidizing agent, for instance in such a way that these are controlled simultaneously or one after the other; or it may be arranged to control two or more admission apparatus for two or more first chambers; or it may control only a part of the total supply of oxidizing agent, the rest being admitted by an apparatus not automatically controlled.