Method for storing discontinuously produced energy

Abstract

A method for temporarily storing energy in which iron ore is reduced with hydrogen and the resulting intermediate product of reduced iron ore and possibly accompanying substances is subjected to further metallurgical processing; the hydrogen is produced through electrolysis of water; the electrical energy required for the electrolysis is regenerative energy from hydroelectric and/or wind and/or photovoltaic sources or other regenerative forms of energy and the hydrogen and/or the intermediate product is produced regardless of the current demand, whenever enough regeneratively produced electrical energy is available; and unneeded intermediate product is stored until there is demand or it is used so that the regenerative energy that is stored therein is also stored and a method for storing discontinuously produced energy in which the discontinuously produced energy, when it is present or after its production, is conveyed into a process in which a storable intermediate product is produced from a source material and the storable intermediate product is stored until it is required and retrieved for the production of an end product.

1 . A method, for storing discontinuously produced energy, comprising:
 supplying the discontinuously produced energy, when it is present or after it is produced, to a process in which a storable intermediate product is produced from a source material;   storing the storable intermediate product until it is required; and   retrieved retrieving the storable intermediate product for the production of an end product;   wherein the intermediate product is a ferrous material obtained from a direct reduction method; the source material is iron ore, which is directly reduced with the aid of hydrogen and/or carbon-containing or hydrogen-containing gas flows, and the hydrogen is produced through electrolysis of water using regeneratively produced electrical energy, and the hydrogen for the reduction has at least enough carbon-containing or hydrogen-containing gas added to it in various modifications to make the carbon content in the intermediate product 0.0005 mass % to 6.3 mass %.   
     
     
         2 . The method according to  claim 1 , comprising producing as much intermediate product as an existing discontinuously produced energy quantity permits and storing the intermediate product regardless of a demand for the intermediate product. 
     
     
         3 . The method according to  claim 1 , wherein the intermediate product is a product that is smelted or transformed using electrical energy and/or is a product that is prepared from a raw material or source material through mechanical processing using electrical energy and/or is a product that is transformed by a gas that has been produced using electrical energy. 
     
     
         4 . (canceled) 
     
     
         5 . The method according to  claim 1 , in which iron ore is reduced with hydrogen and with carbon-containing or hydrogen-containing gas flows and the resulting intermediate product of reduced iron ore and possibly accompanying substances is subjected to further metallurgical processing, comprising producing the hydrogen through electrolysis of water wherein the electrical energy required for the electrolysis is regenerative energy from hydroelectric and/or wind and/or photovoltaic sources or other regenerative forms of energy and
 the hydrogen and/or the intermediate product is produced regardless of the current demand, whenever enough regeneratively produced, electrical energy is available, where   unneeded intermediate product is stored until there is demand or it is used so that the regenerative energy that is stored therein is also stored.   
     
     
         6 . The method according to  claim 5 , comprising, in the reduction of the iron ore to produce the intermediate product, adding a carbon-containing or hydrogen-containing gas to the hydrogen in various modifications in order to be incorporated as carbon into the intermediate product in the reduction process. 
     
     
         7 . The method according to  claim 1 , wherein the carbon-containing or hydrogen-containing gas is methane or other carbon-containing gases from industrial processes or from biogas production or the pyrolysis of renewable resources. 
     
     
         8 . The method according to  claim 1 , wherein the hydrogen for the reduction has at least enough carbon-containing or hydrogen-containing gas added to it in various modifications to make the carbon content in the intermediate product 1 mass % to 3 mass %. 
     
     
         9 . The method according to  claim 1 , comprising introducing the reduction gas composed of hydrogen and possibly a carbon-containing or hydrogen-containing gas into the reduction process at a temperature of 450° C. to 1200° C. 
     
     
         10 . The method according to  claim 1 , wherein excess pressure in the reduction is between 0 bar and 15 bar. 
     
     
         11 . The method according to  claim 1 , wherein a ratio between hydrogen from regenerative production and carbon-containing or hydrogen-containing gas flows is varied continuously as a function of availability; when there is sufficient regenerative energy, hydrogen from the production with regenerative energy is used, and in the absence of discontinuously produced regenerative energy, the system switches to carbon-containing or hydrogen-containing gas flows from continuously produced regenerative energy. 
     
     
         12 . The method according to  claim 1 , comprising adjusting the content of hydrogen and/or carbon-containing or hydrogen-containing gas flows in the overall gas flow using a predictive control; wherein the predictive control is used to measure the predicted yield/production quantity of hydrogen and/or regenerative energy and/or carbon-containing or hydrogen-containing gas flows from biogas synthesis or from the gasification of renewable resources and/or forecasts flow into the estimation of regenerative energy; and demand predictions of other external consumers also flow into the process, thus permitting the electrical energy from regenerative sources to be distributed optimally and in the most economical fashion. 
     
     
         13 . The method according to  claim 1 , wherein almost the entire gas flow that exits the direct reduction system is conveyed back into the process.