An apparatus is disclosed for a metallurgical furnace having a roof with an integrated off-gas hood. The roof has a hollow metal roof. The hollow metal roof has a top, a bottom, an outer sidewall and an inner sidewall. An opening extends from the top to the bottom and is defined by the inner sidewall. The opening is configured for one or more electrodes to pass therethrough. An enclosed space is defined between the top, the bottom, the inner sidewall and the outer sidewall. A spray-cooled system is disposed in the enclosed space and configured to spray coolant in the enclosed space on the bottom surface of the hollow metal roof. A channel having walls is disposed through the enclosed space, wherein the spray-cooled system extends between the top of the hollow metal roof and the wall of the channel.

Waste heat recovery in an ammonia-based desulfurization and decarbonization system. The heat in the decarbonization system may be removed by using the heat of the process gas before desulfurization. The process gas before desulfurization may heat an intermediate medium through a gas heat exchanger. The intermediate medium may drive a refrigerator for refrigeration. A refrigerant may obtain the cooling capacity and may then cool the decarbonized process gas through a liquid-liquid heat exchanger.

Processes and plants for producing cement clinker, wherein no recirculation of preheater exhaust gases occurs and the ratio of solid fed in to exhaust gas in the preheater is set to greater than 1.0 kg of solid to gas.

The present application describes an industrial calciner for particulate material, wherein the industrial calciner comprises: a calcination vessel; and a gas supply system in fluid communication with the calcination vessel, the gas supply system configured to supply a flow of calcination gas to the calcination vessel, wherein the industrial calciner further comprises at least one electric heater configured to heat the calcination gas, the industrial calciner further comprising at least one humidity modifier and a humidity control system for controlling the output of the at least one humidity modifier. Use of the industrial calciner and a method of calcining particulate material with the industrial calciner are also described.

A furnace for a heating, ventilation, and/or air conditioning (HVAC) system includes a heat exchanger tube including a tube inlet and a tube outlet, such that the heat exchanger tube is configured to receive combustion products via the tube inlet, circulate the combustion products through the heat exchanger tube, and discharge the combustion products via the tube outlet. Additionally, the furnace includes a collector box coupled to the heat exchanger tube and having a cavity configured to receive the combustion products via the tube outlet. The furnace includes a diverter plate disposed within the cavity, where the diverter plate overlaps the tube outlet to disperse the combustion products received via the tube outlet throughout the collector box.

Techniques for utilizing excess heat generated by an oven to generate electricity are provided. In one example, an oven can comprise a coolant pathway positioned adjacent to a hollow space within the oven, wherein the hollow space can contain heat. The oven can also comprise a chamber in fluid communication with the coolant pathway. The oven can further comprise a turbine in fluid communication with the chamber and an outlet. Moreover, the oven can comprise a generator connected to the turbine, wherein rotation of the turbine can power the generator.

A device for preheating rod-like, metal workpieces, in particular aluminium rods, by means of a fluid flow heated by residual heat or waste heat of a combustion process occurring in a heating device for heating the workpieces. The device has a preheating chamber for receiving at least one workpiece, wherein, in order to transfer the heat from the fluid flow to a heat transfer medium flow in a fluid flow line between a fluid flow connection and the preheating chamber, a heat-exchanger unit is provided in such a way that the workpiece is preheated indirectly via the heat transfer medium flow heated in the heat-exchanger unit by the fluid flow.

An exhaust structure includes a piping section, wherein the piping section has a first inner diameter in a central region of the piping section, the piping section has a second diameter in at least one of an inlet or an outlet, and the second diameter has a same value as the first inner diameter. The exhaust structure further includes a plurality of smoothing layers configured to resist turbulence and condensation produced by a flow of one or more gasses in the piping section.

A total heat energy recovery system for furnace-process phosphoric acid is disclosed by the present disclosure, and relates to the technical field of phosphorus chemical industry. The system comprises a phosphorus burning tower, a hydration tower, an absorption tower, a Venturi tube, a demister, an induced draft fan, a deaerator, an economizer, a dilute acid circulating tank, a phosphoric acid pump, and a feedwater pump. In consideration of the whole process system, fresh soft water is deoxidized after being heated by an upper head of the phosphorus burning tower and a gas guide tube, and the deoxidized water is then pumped into the economizer by a high-pressure pump to recover the heat of the hydration tower and then enters a steam pocket of the phosphorus burning tower to generate medium-high pressure steam. Therefore, unified recovery of the heat of a furnace-process phosphoric acid device is achieved, the medium-high pressure steam is generated, the effective energy is improved, a circulating cooling tower of the furnace-process phosphoric acid device is omitted, and the production system is efficient, energy-saving, environment-friendly, and green.

A method for upgrading used or rejected electric battery cells, which include upgradable compounds, such as iron, zinc, manganese, copper, and fixed and volatile carbon, and heavy metals and dangerous compounds. The used or rejected battery cells are introduced as a load into a furnace for melting metal, such as a cupola furnace, a free arc furnace, or an induction furnace. A device for purifying gases produced by the furnace and for capturing and removing noxious elements, such as mercury, chlorides, and fluorides, and heavy molecules such as dioxins, furans, and aromatic substances, is provided in a discharge route of the hot gases, downstream from the melting furnace.