The invention discloses a double-flow-state clean combustion boiler and a double-flow-state clean combustion technology. The boiler comprises a bubbling fluidized bed and a circulating fluidized bed, wherein an overflow port and a first window are formed between a circulating fluidized bed firebox and a bubbling fluidized bed firebox; air distribution plates and primary air chambers are arranged at the bottoms of the circulating fluidized bed and the bubbling fluidized bed; a circulating fluidized bed smoke outlet is connected with a cyclone separator, a return feeder and a return leg in sequence, and then connected to the lower part of the circulating fluidized bed firebox and a tail flue connected with a smoke outlet of the cyclone separator; at least one set of bubbling fluidized bed is arranged on the side surface of the circulating fluidized bed firebox. Under a condition of using the same fuel particles, the clean combustion boiler can decompose and adjust the parameters that possibly conflict in the adjusting process of indexes, so that the indexes can be optimized to the utmost extent through adjustment of a single parameter or a few parameters (such as primary air volume, secondary air volume and oxygen content).

Double-flow-state clean combustion boiler and double-flow-state clean combustion technology

The invention relates to a method for reducing metal oxide-containing feedstock (1), in which the metal-oxide containing feedstock (1) is reduced in at least two fluidised bed aggregates (RA, RE) using a reduction gas (2), at least part of the off gas (3) produced being recycled and the metal-oxide containing feedstock (1) being conveyed into the fluidised bed aggregate RE by a propellant gas. The invention further relates to a device for carrying out the claimed method.

Pneumatic ore charging

A system for fluidized bed reduction of powdered iron ore. Use of high-gas-velocity processing accelerates iron ore reduction speed and greatly improves the gas-treatment capabilities of a unit-cross-sectional fluidized bed. Use of parallel connections involving reduced coal gas lessens the volume of gas passing through a single-stage fluidized bed. Use of serial/parallel-connection processing involving reduced coal gas increases the coal gas utilization rate. The invention achieves the highly-effective reduction of powdered iron ore in a fluidized bed under near-atmospheric pressure. A reduction method based on the present system is also disclosed.

System and method for fluidized bed reduction of powdered iron ore

The invention discloses an iron ore powder and coal powder Y type entrained-flow bed classified reduction gasification iron smelting process After uniform mixing with coal powder, pre-reduced hot iron ore powder and a gasifying agent are respectively sprayed into a gasifying chamber of a Y type entrained-flow bed through a top nozzle and a side nozzle for combustion gasification and reduction reaction; multiple sprayed currents, generated by the top nozzle and the side nozzle, are collided with each other in the center of a hearth to form a Y type rotary collision high-temperature reaction area; solid ash is thrown to the furnace wall of the gasifying chamber, and rotationally flows down; the stop and reduction time of slag is prolonged by above 10 times; thick synthesis gas and the slagflow to a slag-iron separation chamber; the slag is settled and separated as molten iron and iron slag for discharging to enter next procedures; high-temperature synthesis gas is exhausted from the side surface of the top of the separation chamber, and the iron ore powder is sucked to enter a lifting pipe for preheating and partial reduction; the pre-reduced hot iron ore powder separated from thetop of the lifting pipe is mixed with the coal powder as Y type entrained-flow bed feeds; tail gas is purified for afterburning; and afterheat is recycled

Iron ore powder and coal powder Y type entrained-flow bed classified reduction gasification iron smelting process

The invention discloses a system and method for vanadium-titanium magnetite ore powder fluidized high temperature rapid oxidation and reduction. The system adopts three boiling fluidized beds connected in series to carry out vanadium-titanium magnetite ore powder fluidized high temperature rapid oxidation and reduction treatment. The vanadium-titanium magnetite ore powder is preheated and dried, then is fed into an oxidized bed and then is subjected to high temperature oxidation treatment, the product is fed into two stages of reduction beds and is subjected to high temperature reduction, oxidation tail gas is used for preheating and drying vanadium-titanium magnetite ore powder, the reduced tail gas undergoes heat exchange with the oxidized air, then the oxidized component is removed through cleaning and the reduction tail gas is recycled. The pre-oxidization treatment unit and the low gas velocity fluidized bed are connected in series so that high temperature fluidization performances of the vanadium-titanium magnetite ore powder are obviously improved, ore reaction efficiency is improved and process energy consumption is reduced. The system and method have the advantages of high reaction efficiency and high energy utilization rate.

System and method for vanadium-titanium magnetite ore fluidized oxidation and reduction

A system and method for the fluidized direct reduction of iron ore concentrate powder. A two-phase fluidized bed is used for the direct reduction of iron ore concentrate powder. Each phase of the fluidized bed is formed by a bubbling bed and a circulating bed. Use of serial-connection processing involving gas and of high-gas-velocity processing of the circulating bed increase the gas utilization rate and the reduction efficiency of single-phase reduction. Once reduced gases are subjected to preheating, each gas is sent into an initial reduction phase and a final reduction phase so as to implement reduction of minerals. Use of mixed-connection processing involving gas appropriately reduces processing pressure. Hot flue gas produced by combustion in a gas heater is sent to a mineral pre-heating system that is used for pre-heating iron ore concentrate powder.

System and method for fluidized direct reduction of iron ore concentrate powder

Provided are a system and method for producing a high-purity divanadium pentoxide powder; using fluidizing low-temperature chlorination, industrial-grade divanadium pentoxide is converted to vanadium oxytrichloride; by means of a fluidization gas exchanging heat with a chlorination flue gas, a chlorination gas is preheated and an appropriate amount of air is added, which causes the carbon powder to partially combust, thus providing a balanced supply of heat during the process of chlorination, improving chlorination efficiency, and ensuring good selectivity of low-temperature chlorination; the vanadium oxytrichloride is distilled and purified, then fluidized-vapor-phase hydrolyzed, and fluidized-calcined to produce a high-purity divanadium pentoxide product and a hydrochloric acid solution by-product. The system and method have the advantages of highly adaptable starting materials, no discharge of polluted wastewater, low energy consumption in production and low cost in operation, and stable product quality; the invention is suitable for use in the large-scale industrial production of high-purity divanadium pentoxide having a purity of 4N or higher.

范川林

Papers

System and method for fluidized direct reduction of iron ore concentrate powder

System and method for fluidized bed reduction of powdered iron ore

System and method for preparing high-purity divanadium pentoxide powder