Abstract: Electronic thermostat for an oven that includes a shaft with a first end suitable for being coupled to a rotary knob for modifying the temperature set point according to its angular position, and an electronic board with a potentiometer, a second end of the shaft being coupled to the potentiometer. The electronic thermostat includes a support having a base in which the electronic board is fixed, a side wall extending from the base, and a support wall extending from the base and arranged parallel to the side wall, the shaft going through the side wall and the support wall.

Abstract: A method of operating a home appliance having a treating chamber for receiving an article for treatment according to an automatic cycle of operation stored in memory of a programmable controller operably controlling one or more actuators to implement the cycle of operation, the method includes implementing the cycle of operation, receiving sensor feedback, calculating gradients from the sensor feedback, and controlling an actuator based thereon.

Abstract: A device and method of controlling excess air during and after ignition of a gas furnace by operating a variable speed combustion blower assembly at an initial speed; operating a gas valve assembly and a burner assembly to initiate an ignition sequence; operating the variable speed combustion blower assembly at an increasing plurality of speeds until an excess air measurement is less than or equal to a predetermined value, and operating the variable speed combustion blower assembly at a steady state airflow rate to maintain the excess air measurement at the predetermined value.

Abstract: The invention relates to a dental furnace, in particular a firing furnace or press furnace, for firing or pressing a dental restoration part which is receivable in the furnace, possibly after pre-heating in a pre-heating furnace, and which is placeable on a base, in particular centrally thereon, wherein the dental furnace comprises a firing chamber whose diameter is larger than, in particular at least twice as large as, the largest dental restoration part to be fired, and which comprises a control device and an operating unit at the or for the dental furnace (10), wherein by means of the operating unit (26) the size and/or the weight and/or the number of the dental restoration part(s) (18) to be fired or pressed is adjustable in units.

Abstract: A method and apparatus comprising a cure of a curable material. A cure of a curable material is initiated by using cure parameters. The cure parameters are based on material data related to curing the curable material. Temperature values are obtained based on temperatures measured periodically during the cure by a plurality of sensors. A cure setting is adjusted during the cure based on at least one cure parameter of the cure parameters and at least one temperature value of the temperature values to substantially maintain a desired effect. The cure parameters comprise a hot threshold, a cold threshold, a hot alarm, and cold alarm.

Abstract: An energy consumption controller may be communicatively coupled with a plurality of alternative energy sources and an engine. The controller may be configured to manage energy consumption from the alternative energy sources interconnected with the engine and to keep the engine within a desired temperature range. Within the desired temperature range, the engine will start and run at a full load more rapidly than if the engine cooled excessively. The controller may change the selected energy source as required, based on factors such as cost, engine maintenance and testing and/or imminent need of the engine.

Abstract: A rotary aluminum kiln temperature regulation system comprising a temperature sensing device in the kiln that is configured to take temperature readings in an area of the kiln in proximity to the temperature sensing device. The system including a wireless transmitter operatively associated with the temperature sensing device and a receiver wirelessly associated with the transmitter, such that the transmitter and receiver wirelessly transmit the temperature readings taken by the temperature sensing device from the transmitter to the receiver. The system also including a control unit operatively connected to the receiver that is configured to receive the transmitted temperature readings and determine when the transmitted temperature readings exceed a predefined temperature set point. The control unit operatives one or more forward feed control loop subsystems that assist in safely operating the kiln in accord with a predetermined temperature profile programmed into the control unit.

Abstract: A heat source system has a plurality of heat sources that can be utilized therein. The plurality of heat sources include unused heat such as sewage and wastewater generated in a facility in which an external load that receives a supply of heating medium heated or cooled by using the heat sources is installed. A system control device (10) of the heat source system determines potential temperatures and amounts of potential heat of the individual heat sources; and selects heat sources based on the potential temperatures and the amounts of potential heat.

Abstract: Provided are a method and an apparatus for controlling combustion in an oxygen fired boiler which are easily applicable to an existing air fired boiler for easy and stable control of the combustion. Oxygen with a setting amount in accordance with a boiler load demand 35 is supplied to a boiler body 4. Heat absorption amount of the boiler is measured from inlet temperature of feedwater supplied to the boiler body 4 and outlet temperature of steam. Recirculation flow rate of combustion exhaust gas 14a is controlled such that heat absorption amount 41 of the boiler body 4 becomes equal to a targeted heat absorption amount 42 to thereby control oxygen concentration in all gas guided to the boiler body 4.

Abstract: A heater-integrated canister unit may include a canister, a temperature controller integrally coupled with the canister to indirectly heat a charcoal inside the canister by increasing a temperature of a space in the canister, and an electronic control unit controlling the current supplied to the temperature controller. The temperature controller may be disposed at the opposite side of the evaporation gas intake port in the canister and support the charcoal or may be coupled to the outside of the canister by a seating slot formed in the canister. The temperature controller may include a heater plate transmitting the current by forming a positive electrode and a negative electrode, a connector supplying the current to the heater plate and a heater generating heat on the heater plate.

Abstract: A rising characteristic of a temperature is improved, and high-accuracy temperature control is enabled. A temperature sensor according to the present invention includes a temperature detecting element, a heat receiving body to which the temperature detecting element is fixed and that is heated by receiving surrounding heat, a heat receiving body supporting mechanism supporting the heat receiving body at a predetermined position, and a protective tube adjusting the heat receiving body in a predetermined direction and at a predetermined position and holding the heat receiving body therein. In the temperature sensor, the heat receiving body is in a flat plate shape, the temperature detecting element is fixed to the heat receiving body, and the heat receiving body supporting mechanism includes a plurality of connecting narrow tubes connected to one another and a connecting wire passing through the respective connecting narrow tubes to connect and support all the connecting narrow tubes.

Abstract: A delayed coking heater for heating a feedstock to delayed coking temperature is disclosed. The delayed coking heater may include: a heater including a radiant heating zone comprising a lower portion including a hearth burner section and an upper portion including a wall burner section, the hearth burner section comprising a plurality of hearth burners located adjacent to the bottom hearth for firing in the radiant heating zone; and the wall burner section comprising a plurality of wall burners located adjacent to opposing walls; and a multiple parallel serpentine heating coil located in the radiant heating zone.

Abstract: A heater-integrated canister unit may include a canister, a temperature controller integrally coupled with the canister to indirectly heat a charcoal inside the canister by increasing a temperature of a space in the canister, and an electronic control unit controlling the current supplied to the temperature controller. The temperature controller may be disposed at the opposite side of the evaporation gas intake port in the canister and support the charcoal or may be coupled to the outside of the canister by a seating slot formed in the canister. The temperature controller may include a heater plate transmitting the current by forming a positive electrode and a negative electrode, a connector supplying the current to the heater plate and a heater generating heat on the heater plate.

Abstract: The present invention provides a method and apparatus for thermally processing plastic discs, in particular mould wafers.

Abstract: An energy savings water heater is described. The water heater is controlled by an energy savings algorithm that uses one or more of a variable setpoint differential, a variable setback threshold, additional setback thresholds, and an adjustable minimal setpoint to improve the operation of an energy efficient water heater. Additionally or alternatively, a different setback control algorithm may be used that obtains additional data to adjust the setpoint. As a result, the operating cost of the water heater is reduced, while minimizing user complaints of cold water.

Abstract: The temperature of an object is controlled by a feedback control algorithm based on the temperature control characteristics of a homeothermic plant.

Abstract: The present invention relates to an arrangement (10) for heating of a magnetic material (100) located in the centre region of an inscribed sphere within a region of action, which arrangement comprises:—selection means (210) for generating a magnetic selection field (211) having a pattern in space of its magnetic field strength such that a first sub-zone (301) having a low magnetic field strength and a second sub-zone (302) having a higher magnetic field strength are formed in the region of action (300),—drive means (220) for changing the position in space of the two sub-zones (301, 302) in the region of action (300) by means of a magnetic drive field (221) so that the magnetization of the magnetic material (100) changes locally, and—control means (76) for controlling the drive means (220) to change the position in space of the first sub-zone (301) along a sequence of locations around said inscribed sphere for so long and with such a frequency that the centre region of said inscribed sphere is heated.

Abstract: The furnace of the facility includes partitions in which hot gases from the baking of carbonaceous blocks circulate, and heating ramps (21, 22, 23) revolving in relation to the furnace, equipped with burners or fuel injectors. Gas circulation lines (24) are defined along the partitions between an air blowing leg (20) and a corresponding gas suction leg (12). To detect even partial partition blocking of a partition, the process includes, on a continuous basis: a. for each gas circulation line, continuous recording of at least one of the following measured parameters: temperature, pressure, flow, oxygen concentration and carbon monoxide concentration; b. evaluation of at least one factor from the measured parameters; c. comparison of this factor with a corresponding reference value; d. emission of a malfunctioning signal when the comparison between the factor and the corresponding reference value does not meet with the predefined safety criteria.

Abstract: A multi-zone portable heater is provided having an oscillating heater and a plurality of remote sensors. The plurality of remote sensors are radially positionable about the oscillating heater in a spaced apart configuration, each defining a heating region. The remote sensors read a region temperature in their corresponding heating region and can transmits the corresponding region temperature to the heater signal transmitter/receiver. Alternatively, the oscillating heater can transmit a set temperature to each of the plurality of remote sensors, where the remote sensors calculates a region temperature difference between the read region temperature and the set temperature. The region temperature difference being transmitted to the oscillating heater. In this manner, the operational parameters of the oscillating heater can be selectively controlled for each of the regions.

Abstract: A method for the temperature control and/or regulation of a heating device (10) for preforms (46) made from a thermoplastic material, the method being intended for controlling the temperature of the preforms (46) prior to a subsequent blow molding or stretch blow molding process. The temperature control process includes at least two distinct, consecutive heating stages (12, 14). At least one temperature reading of the preforms after the first heating stage is taken, and deviations of the at least one temperature reading from a specified set point temperature is determined, a first temperature reading of the at least one temperature reading being taken after the first heating stage. Radiators in the second heating stage are regulated or adjusted as a function of the first temperature reading and temperature deviations of the preforms from the specified set point temperature are compensated for prior to exit of the preforms from the heating device.

Abstract: A rotary aluminum kiln temperature regulation system comprising a temperature sensing device in the kiln that is configured to take temperature readings in an area of the kiln in proximity to the temperature sensing device. The system including a wireless transmitter operatively associated with the temperature sensing device and a receiver wirelessly associated with the transmitter, such that the transmitter and receiver wirelessly transmit the temperature readings taken by the temperature sensing device from the transmitter to the receiver. The system also including a control unit operatively connected to the receiver that is configured to receive the transmitted temperature readings and determine when the transmitted temperature readings exceed a predefined temperature setpoint.

Abstract: A cooling fan controller is provided for controlling the revolving speed of a cooling fan that introduces outside air as a cooling wind to cool a fluid being cooled; in order to optimally control the revolving speed if the cooling fan in accordance with load, and to suppress noise caused by the cooling fan. The cooling fan controller includes a fluid temperature sensor 40 for sensing a temperature To of the fluid, an air temperature sensor 30 for sensing a temperature Ta of the air, and a control 20 for calculating a difference between the fluid temperature To sensed by the fluid temperature sensor 40 and the air temperature Ta sensed by the air temperature sensor 30, and setting a target revolving speed Nf of the cooling fan in accordance with a magnitude of the calculated difference.

Abstract: A marine life decontamination system embodiment of the present invention comprises a drive-in chamber large enough to accommodate a boat on its trailer and even the two vehicle too. Once inside the chamber, eaters are used to bring the boat and trailer temperatures up to 112° F. to 165° F. for a minimum soak-in time, with five minutes being sufficient in most cases. Humidity measurements of the off-gassing water vapors are used to sense when all the available water that could harbor marine life has been removed. Such combination of high temperatures and no available water assures that pests cannot survive to contaminate a new body of water.

Abstract: A substrate treating apparatus includes a treating unit for treating substrates, a piping for supplying a treating liquid to the treating unit, a heater mounted on the piping, an electronic thermal unit mounted on the piping in series with the heater, a temperature sensor for measuring a temperature of the treating liquid, and a controller for controlling the heater and the electronic thermal unit. The controller sets a first temperature control mode for performing a room temperature control using the electronic thermal unit when the temperature measured by the temperature sensor is below a predetermined boundary temperature between room temperature and high temperature, and for performing a high temperature control with the heater when the temperature measured by the temperature sensor is above the predetermined boundary temperature between room temperature and high temperature.

Abstract: A water heating system including a tank to store water, a temperature sensor positioned to detect a temperature of the water, and a temperature control element configured to alter the temperature of the water. The system also includes a controller configured to control the temperature of the water based on a first temperature threshold during a first time period and monitor the amount of time that the temperature control element is in either the activated state or the deactivated state during the first time period. The control then determines a second temperature threshold for a subsequent time period based on the monitored amount of time.

Abstract: The multi-chamber heat treatment device includes a temperature sensor (31) attached to an object to be treated (X), a signal transmission unit (30) which transmits a detected signal from the temperature sensor to the outside of a heating chamber and a cooling chamber, and a temperature measuring unit (40) which is arranged outside the heating chamber and the cooling chamber to measure the temperature of the object from the detected signal of the temperature sensor transmitted from the signal transmission unit (30).

Abstract: A substrate treating apparatus includes a treating unit for treating substrates, a piping for supplying a treating liquid to the treating unit, a heater mounted on the piping, an electronic thermal unit mounted on the piping in series with the heater, a temperature sensor for measuring a temperature of the treating liquid, and a controller for controlling the heater and the electronic thermal unit. The controller sets a first temperature control mode for performing a room temperature control using the electronic thermal unit when the temperature measured by the temperature sensor is below a predetermined boundary temperature between room temperature and high temperature, and for performing a high temperature control with the heater when the temperature measured by the temperature sensor is above the predetermined boundary temperature between room temperature and high temperature.

Abstract: Provided are a substrate processing apparatus, a semiconductor device manufacturing method, and a temperature controlling method, which are adapted to improve equipment operational rate. A calculation parameter computing unit computes a calculation parameter using at least a first calculation parameter correction value determined by a first calculation parameter setting unit based on an accumulated film thickness on a reaction vessel, a second calculation parameter correction value determined by a second calculation parameter setting unit based on an accumulated film thickness on a filler wafer, and a third calculation parameter correction value determined by a third calculation parameter setting unit based on the number of filler wafers.

Abstract: The invention relates to a dental furnace (1) comprising a hood-shaped combustion chamber (3) with a heating element (12) that is placed therein and an opening (13), and a closing plate (4) which is arranged so as to be movable relative to the combustion chamber (3) and is used for accommodating a material (5) that is to be baked, particularly a tooth replacement object. Said dental furnace (1) further comprises a sensor (31) for determining the combustion chamber temperature. In order to optimize the drying time and closing time, a measuring instrument (7b) is provided for recording the actual value of the position of the closing plate relative to the combustion chamber (3) while an arithmetic unit (51) is provided for determining the deviation from the comparison between the determined actual value and a defined required value so as to derive a control variable for triggering the relative position between the closing plate (4) and the combustion chamber (5).

Abstract: An object of the present invention is to accurately control temperatures of microorganisms or the like. In the present invention, a temperature controller comprises a plurality of cells for storing microorganisms or the like, heaters, and a cooling section. The heaters selectively heat the plurality of cells, and the cooling section wholly cools the plurality of cells. When the maximum value of temperature of a plurality of places is not lower than a first lower limit, the cooling section is driven. When a temperature of one place is not higher than a first lower limit, the heater to heat the place is driven. When the maximum value is not higher than a second lower limit, the cooling section is stopped. When a temperature of one place is not lower than a second upper limit, the heater to heat the place is not driven.

Abstract: To provide a processing system for a process object capable of preventing a transport arm mechanism from being thermally damaged, so as to effectively perform a transport operation of the process object. A processing system 2, which takes out a process object W from a storage box 6 for process object, and thermally process the process object, includes: a vertical processing unit 24; a process-object transport area 10 disposed below the processing unit; a plurality of process-object boats 20 configured to hold the process objects; a boat elevating means 68 configured to vertically move the process-object boat 20; a boat table for transport 52, on which the process-object boat can be placed; and a transport arm mechanism configured to transport the process objects between the storage box 6 and the process-object boat 20 placed on the boat table for transport 52. The transport arm mechanism 56 is vertically moved by an arm elevating means 58.

Abstract: The present invention generally provides a system for warming an outdoor surface. The system includes a heat exchange unit to provide heated air for use across the surface to melt snow or ice or to warm, evaporate or distribute water. The heat exchange unit is used to recapture the heated air. The present invention also generally provides a method of warming an outdoor surface. The method comprises the steps of providing heated air across the surface to melt snow or ice or to warm, evaporate or distribute water, recapturing the heated air, and redistributing the heated air across the surface.

Abstract: A method and apparatus for trimming the edges of a float glass ribbon whose thickness can vary between 0.4 mm and 24 mm in which a specific depth crack is generated for the respective thickness. The depth of the crack is actively influenced by energy introduced by means of a laser which is controlled as a function of the surface temperature of the float glass ribbon and by a subsequent cooling whose acting period is variable. To ensure a permanently reliable process, the severing crack and the thickness of the float glass ribbon are detected in order to initiate a new initial crack immediately in the event that the severing crack should break up and so that a cutting unit comprising the scribing device, the beam-shaping optics and the cooling nozzles is always at a constant vertical distance from the surface of the float glass ribbon. The method and apparatus are distinguished particularly by the fact that only a low laser power is required.

Abstract: A system for controlling a temperature of a liquid residing within a tank comprises a temperature sensor, a temperature control element, memory, and logic. The temperature sensor is configured to detect the temperature of the liquid residing within the tank, and the temperature control element is coupled to the tank. The memory stores data indicative of a usage history of the tank, and the logic is configured to automatically control the temperature control element based on the data.

Abstract: A baking apparatus according to one embodiment of the invention includes a hotplate which performs heat treatment to a substrate placed on the hotplate, a base which has at least three support pins passing through through-holes made in the hotplate and supporting the substrate on the hotplate from a backside of the substrate and is vertically movably placed, and a plurality of sensors which are provided at a tip portion of each support pin respectively and sense contact with the substrate.

Abstract: A system for determining dry cleaning timing, includes: a manufacturing apparatus configured to process materials assigned by a sequence of lots; an apparatus controller configured to control the manufacturing apparatus and obtaining operational conditions of the manufacturing apparatus as apparatus information; a lot information input terminal configured to obtain process conditions of one of the lots as lot information; an apparatus information storage unit configured to store the apparatus information from the apparatus controller as an apparatus information database; a lot information storage unit configured to store the lot information from the lot information input terminal as a lot information database; and a cleaning determination unit configured to determine timing to perform a dry cleaning of the manufacturing apparatus based on the apparatus information database and the lot information database.

Abstract: The present invention includes a method and system for limiting the ramp rate of a variable under control in order to control stress in a process or plant under control. The present invention takes a limit curve provided by the user and combines that limit curve with a scale factor curve obtained from a model of the system to produce an allowable limit curve. A ramp rate limiter then uses the allowable limit curve to control the ramp rate of the variable under control such that the ramp rate of the variable under control is able to achieve the maximum allowable limit but no more.

Abstract: Systems and methods for performing adjustable ratio control for a furnace with a plurality of workpieces located within a furnace and a sensor for determining the temperature of each of the workpieces. Adjustable ratio control is performed by controlling the temperature of an atmosphere of the furnace wherein a first workpiece with a lower temperature is heated at a higher rate than a second workpiece with a higher temperature.

Abstract: In a known control method, a large deviation between the temperature of a heating plate and a temperature-setting pattern occurs, and an overshoot or undershoot occurs. Therefore, a workpiece is unstably formed, the number of defective parts is increased and the productivity is decreased. Any two temperatures from among the temperature of the heating medium in the inlet manifold 5 that distributes and supplies the heating medium to each heating plate, the temperature of the heating medium in the outlet manifold 8 that collects the heating medium discharged from the heating plates 4 and the temperature of the heating plates 4, are detected. Then, a temperature value is obtained by selecting any one of the two temperatures based on a temperature-setting pattern 16, or is obtained by obtaining a weighted average of at least two temperatures from among the three temperatures based on preset weights.

Abstract: A substrate cooling unit comprises a cooling plate on which the substrate is placed, a cooling temperature adjusting element which adjusts the cooling plate to a predetermined temperature, a temperature controller which controls a temperature of the cooling temperature adjusting element according to a transfer function, a temperature sensor attached to the cooling plate, and a control parameter changing section which changes at least any one setting of a proportional operation coefficient, integral time or derivative time among control parameters in the transfer function based on a temperature of the cooling plate detected by the temperature sensor after the substrate that is an object to be cooled is placed on the cooling plate.

Abstract: A process controls oxy-boost firing and air-fuel burner firing in furnaces, including large glass furnaces such as float furnaces. The large side-fired regenerative float furnaces use oxy-boost firing for a variety of reasons, including production increase, improved glass quality, lowering of superstructure temperatures, and reduction of emissions. An adaptive controller receives input data from process parameter sensors throughout the furnace, and adjusts its control logic for controlling both the oxy-boost burners and the air-fuel port burners.

Abstract: A radiation furnace assembly for use in heating parts. The radiation furnace assembly includes a muffle having a top side, a bottom side, and a first side wall. The muffle defines a chamber with a main heating portion and a first side heating portion. Disposed adjacent to the muffle are top and bottom heating elements. A first control device is used to adjust the temperature of at least one of the top and bottom heating elements thus controlling the temperature within the main heating portion of the chamber. A first side heating element is disposed adjacent to the first side wall of the muffle. A second control device is used to adjust the temperature of the first side heating element independently of the top and bottom heating elements to increase the temperature within the first side heating portion of the chamber relative to the main heating portion.

Abstract: An oxy-combustion firing configuration, process, and apparatus can reduce the consumption of oxygen and fuel in an oxy-fuel combustion processes. Processes in accordance with the present invention include operation of an automated logic control device which controls an oscillating valve and controller. The valve and controller are used to oscillate the fuel and/or oxygen supplied to individual burners in a furnace. The oscillating parameters, such as frequency, amplitude, duty cycle, and phase difference between individual burners and their stoichiometry ratio are set to initiate preferable oxy-combustion in that furnace. Selective burner placement in the furnace enables the formation of deflagration zones which can provide very intense heating and complete combustion.

Abstract: A heat flux measuring device for transporting through a heated chamber, the device having an array of sensors, each sensor comprising first and second surfaces bounding a region, a thermally insulating layer substantially occupying said region, and means for providing a signal which is a measure of the temperature difference across the layer. The said first surface of each sensor is in thermal contact with a heat sink and the said second surface of each sensor is exposed.

Abstract: The present invention includes a method and system for limiting the ramp rate of a variable under control in order to control stress in a process or plant under control. The present invention takes a limit curve provided by the user and combines that limit curve with a scale factor curve obtained from a model of the system to produce an allowable limit curve. A ramp rate limiter then uses the allowable limit curve to control the ramp rate of the variable under control such that the ramp rate of the variable under control is able to achieve the maximum allowable limit but no more.

Abstract: A substrate heater having a chamber, a heating element located in the chamber, and an elevator having a substrate holder. The holder can hold a plurality of planar substrates in a general spaced stacked configuration. The holder can be moved to allow substrates to be inserted and removed from various locations on the holder. In one embodiment the substrates are located very close to each other to accelerate the rate of heat transfer to newly inserted substrates. In another embodiment, the holder has an individual horizontal heater on the elevator for each substrate.

Abstract: A thermal protection system for a chemical vapor deposition machine (CVD). The system of the present invention includes a thermal sensor for providing a temperature signal corresponding to a CVD chamber temperature, a heating component for heating the CVD chamber, and a controller for regulating the CVD chamber temperature. The controller is coupled to receive the temperature signal and to control the heating component in response thereto. An interlock circuit is coupled between the heating component and the controller. The interlock circuit has an open state and a closed state. A comparison circuit is coupled to receive the temperature signal and coupled to control the interlock circuit, wherein the comparison circuit effects a comparison between the temperature signal and a reference and commands the interlock to the open state when the temperature signal exceeds the reference.

Abstract: A method of controlling the feeding of part trays into a roller-hearth brazing furnace includes feeding a part tray into the furnace after the expiration of a time period. The temperatures in each heating zone of the furnace are monitored. After the expiration of the time period and before a part tray is fed into the furnace, these temperatures are compared to a specified temperature range for each zone. If all temperatures within the heating zones are within specification, the time period is decremented by a small amount. This process continues automatically until a temperature in a heating zone is not within specification when the time period expires. When this occurs, the time period is incremented by a small amount, which can be different from or the same as the amount used to decrement the time period.

Abstract: A heater including a housing, a heating assembly having a burner, and at least one of an oxygen level detection assembly adapted to distinguish between a relatively normal oxygen level, a relatively low oxygen level and relatively unsafe oxygen, a carbon monoxide sensor and a combustible gas sensor. The heater may also include an indicator adapted to produce at least one of an audible indication and a visible indication in response to a detection of a relatively low oxygen level, a detection of a predetermined level of carbon monoxide, or a detection of combustible gas.

Abstract: A method and plant for heat treatment of lime sludge (CaCO.sub.3) formed by the causticizing process during the manufacture of paper pulp. The lime sludge is dried and pulverized in a first process stage and preheated in a second process stage by means of hot exhaust gas coming from a kiln. In order to ensure that the temperature in the second process stage does not exceed a predetermined temperature lying within the range from 400.degree.-600.degree. C., the relationship between the amount of energy available in the exhaust gas for preheating in the second process stage and the amount of accumulated energy in the material which is to be preheated is regulated.