A blast furnace slag level estimation method and blast furnace slag level estimation apparatus can estimate the liquid level of slag to a high degree of accuracy. An operation guidance method, method of producing hot metal, and operation guidance apparatus also provide guidance for the operation of a blast furnace based on a highly accurately estimated liquid level of slag. The blast furnace slag level estimation method includes a step (S2) of calculating a liquid level of melt containing slag for each region in a plurality of regions separated by a low permeability zone, using a physical model that takes at least one of hot metal tapping rate, slag tapping rate, hot metal production rate, and slag production rate as an input and that is based on a mass balance assuming existence of the low permeability zone with poor permeation of slag at a bottom of a furnace.

Disclosed is a system and method for evaluating a status of a refractory material in metallurgical vessels, including furnaces and ladles, wherein a slag buildup is formed on the surface of such material as a result of scrap accumulation and chemical reactions occurring during the melting of metals in such vessels. The system and method are operative to determine both a rate of degradation of the material under evaluation, including the thickness of such material, and a measure of the slag buildup to predict and extend the operational life and improve the maintenance plan of the vessel. The system is capable of determining the thickness of and the slag buildup on the entire material under evaluation by sampling a number of regions of such material with different types of sensors, characterizing the surface profile of such material, and using appropriate signal processing techniques and artificial intelligence algorithms.

The invention relates to a melting apparatus (100) for melting paraffin (1), having: a melting container (110) for receiving paraffin (1) to be melted; a storage container (190) for storing molten paraffin (4); having a melting container heating device (120) for heating the melting container (110), having a storage container heating device (191) for heating the storage container (190), having a fluid connection (113) fluidically connecting the melting container (110) and the storage container; the melting container (110), the storage container (190), and the fluid connection (113) being arranged so that molten paraffin (4) flows out of the melting container (110) into the storage container (190).

An apparatus includes: a guide portion in which a reflection plate is disposed in an opening portion at one end, and an antenna is disposed at the other end, and which is to be inserted into a blast furnace through an opening of the furnace; a guide portion moving unit which moves the guide portion to the inside or outside of the furnace; a guide portion rotating unit which rotates the guide portion; and a reflection plate tilting unit which changes a tilt angle of the reflection plate with respect to the antenna. During measurement, the opening portion of the guide portion is protruded into the furnace, and the guide portion rotating unit and the reflection plate tilting unit are driven to scan planarly or linearly the surface of a burden in the furnace.

An immersion device is provided for molten metal, as well as a method for making steel. The immersion device allows a trouble free operation. The immersion device includes a measuring head, a carrier for the measuring head, and a lance detachably connected to the carrier, preferably by a detachable tubular connecting element. A gas path runs from the lance to the detachable tubular connecting element. A gas tight connection is provided between a connecting surface of the lance and the detachable tubular connecting element. The tubular connecting element has wipers in the form of fins, which wipe the connecting surface of the lance during attaching and/or detaching the tubular connecting element and the lance.

The furnace 10 comprises a vessel 12 having a centre axis extending between a roof and a base. The vessel holds a body 20 of material having an upper surface 24 having an upper level l.sub.u. The furnace comprises a non-contact sensor 30.1 for sensing a distance 32 between a reference point and a position on the upper surface. The non-contact sensor comprises an electromagnetic signal transceiver 36, 38, an antenna 40 for launching the signal towards the upper surface and receiving a reflection of the signal and a signal guide 46 extending between the transceiver and the antenna. The transceiver is located at one of a) a level lower than the upper level l.sub.u and b) a level higher than the upper level l.sub.u and beyond a first line 39 which is spaced a distance d.sub.0>0 from the layer on a line 41 perpendicular to the centre axis.

A system for automatic monitoring of smelt flow exiting a recovery boiler based on optical information. A processor is used to read at least one stationarily imaged video sequence, comprising digital image frames, including an area under examination representing at least part of the smelt flow exiting the recovery boiler. The processor is used to identify, in the area under examination, an area distinguishable based on colour and/or intensity information. The processor is used to determine, based on the identified distinguishable area, a monitored flow property of the smelt flow.

The present invention relates to a submerged combustion furnace for melting ceramic frits by means of a submerged combustion process, said furnace comprising at least one control loop with feedback of the overall weight regulating at least one process variable of the furnace for producing ceramic frit.

The invention also relates to a regulating method for a submerged combustion furnace having these features, whereby obtaining a batch production of a ceramic frit having certain characteristics. The regulating method is implemented in the system by means of regulating process variables relating to the production of molten material during production.

The present invention relates to a method for measuring the liquid-metal surface level (13) and the slag surface level (14) in the crucible (1) of a metallurgical shaft furnace comprising the following steps: measuring, at one or more points on the external wall (2) of the crucible, the following variables: the circumferential strain in said external wall (2) by means of a number of strain-gauge sensors (6) fixed to the armor (4) of the external wall (2) of the crucible; and the temperature of said external wall (2) by means of one or more temperature sensors (7) fixed to the armor (4) of the external wall (2) of the crucible; introducing said variables measured at a number of points on the external wall of the crucible into the general equation governing circumferential strain, the solution of which is analytical, and which contains two unknowns, the liquid metal level and the overall liquid metal/slag level, considering set parameters; and solving said equation and obtaining an analytical solution giving the liquid metal surface level (13) and the slag surface level (14) in the crucible (1).

A system and method for sensing the melt level of an ingot and/or molten material within one or more of a melting hearth, a refining hearth, tundish, and/or a casting mold within a furnace system. One or more laser melt height systems is configured and oriented to measure the melt level of one or more furnace system vessels within a closed furnace chamber, and thereby provide control information for regulating an overall melting, refining, casting, and/or atomization process.