A method of cooling a liner in a plasma chamber. A recycle gas is contacted with or passed through the liner to cool the liner and pre-heat the recycle gas. The pre-heated gas is then recycled through the plasma chamber to become part of the plasma forming process. The method further comprises the liner is graphite, the recycle gas passes through at least one cooling channel present in the liner, at least one of the cooling channels are covered with at least one removable liner/channel cover, carbon deposits are formed from the presence of hydrocarbons in the recycle gas, at least one channel is formed in a spiral cooling channel pattern, at least one channel is formed in a substantially straight cooling channel pattern, and a plenum to aid in the production of an even distribution of cooling gas in the channels.

Method and installation for calcining cement raw meal in a calciner whereby fuel and a calciner oxidant having an oxygen content of at least 30% vol are introduced into the calciner so as to generate either an oxidant-lean zone or a fuel-lean zone in the calciner located between the lowermost fuel inlet level and the lowermost oxidant inlet level of the calciner, between 50% and 100% by weight of the raw meal being supplied to the calciner upstream of and/or within the oxidant-lean, respectively the fuel-lean zone.

Employing furnace combustion gases for both thermochemical regeneration and heating of regenerators to preheat oxidant for the furnace provides synergistic efficiencies and other advantages.

The invention provides a powder-gas heat exchanger for exchanging heat between a powder stream and a gas stream in counter-current flow comprising a powder stream mass flow rate substantially equal to a gas stream mass flow rate in a vertical shaft heat exchanger. A hot gas stream may be adapted for use in heating a cool solids stream, or a cool gas stream may be adapted for use in cooling a hot solids stream.

A pressurized cavity is provided around at least a portion or all of a regenerator, within which gas such as flue gas is maintained at a pressure in excess of the pressure within the regenerator, to protect against leakage of gas through the walls of the regenerator.

Disclosed are a flue gas purification and waste heat utilization system and method. The system comprises a flue gas exhaust unit, a primary waste heat utilization unit, a primary flue gas purification unit, a secondary waste heat utilization unit and a secondary flue gas purification unit that are sequentially connected in a flue gas flow direction, wherein the primary flue gas purification unit is configured for removing NO.sub.x, large particles and CO in the flue gas, the secondary flue gas purification unit is configured for removing NO.sub.x and dioxin in the flue gas, an ammonia-spraying device is externally connected between the flue gas exhaust unit and the primary waste heat utilization unit, and the ammonia-spraying device is configured for injecting ammonia gas into the flue gas exhausted from the flue gas exhaust unit.

A method for reducing combustion temperature and/or thermal radiation within a lime kiln of a pulp production plant, which kiln is a rotary kiln having a kiln tube (1) internally covered with refractory tiles (13) and having a burner (2) supplied by fuel for heating of the rotary kiln by a flame (3). The effects are achieved by supplying calcium carbonate containing particles to the flame (3) and/or to surrounding area around the flame (3). The particles are supplied into the rotary kiln by at least one lance (9) to the upper part of the flame (3). Calcium oxide containing particles may be supplied to the rotary kiln to areas surrounding the flame (3) for reducing the thermal radiation to an area over the flame (3) and/or to the area at the side of the flame (3), where the refractory tiles (13) of the kiln are rotating downwards.

The invention relates to a melting unit and method in which: a melting chamber is heated by means of combustion, the combustion fumes are used to heat the air used as a heat-transfer gas, the heated air is used to pre-heat the combustion oxygen and/or the gaseous fuel, the tempered air resulting from the pre-heating is compressed, the compressed tempered air is heated by means of heat exchange with the combustion fumes, and the mechanical and/or electrical energy is generated by expansion of the heated compressed air.

A sintering furnace with a first zone, in particular a burn-off zone, and a second zone, in particular a sintering zone, and also a transitional zone arranged between the first zone and the second zone. The sintering furnace has at least one transporting mechanism for transporting bodies to be sintered on a transporting area. With this transporting mechanism, the bodies to be sintered can be transported from the first zone and through the transitional zone to the second zone. The sintering furnace also has at least one gas removal device with at least one gas removal device opening. Here, the gas removal device opening is at least partially arranged in the region of the transitional zone. Furthermore, a method by means of which gases can be removed from a sintering furnace is claimed.

Disclosed in the present application is a cooling system for a reflow furnace, the reflow furnace comprising a heating zone, and the cooling system being used to regulate a temperature of the heating zone, the cooling system comprising: at least one gas inlet and at least one gas discharge port, the at least one gas inlet and the at least one gas discharge port being disposed on the heating zone; a blowing apparatus; at least one gas intake pipeline, an inlet of the at least one gas intake pipeline being connected to the blowing apparatus, an outlet of the at least one gas intake pipeline being connected to the at least one gas inlet, the at least one gas intake pipeline being able to controllably establish fluid communication between the blowing apparatus and the at least one gas inlet; and at least one gas discharge pipeline, an inlet of the at least one gas discharge pipeline being connected to the at least one gas discharge port, an outlet of the at least one gas discharge pipeline being connected to the outside, and the at least one gas discharge pipeline being able to controllably establish fluid communication between the at least one gas discharge port and the outside. The cooling system of the present application can shorten the time taken for the reflow furnace to change from a higher heating temperature to a lower heating temperature.