65results about How to "Reduce carburization" patented technology

The invention relates to assistant materials used for continuous casting of steelmaking, in particular to a high casting speed continuous casting covering slag used for ultra-low-carbon steel, comprising pre-melt material and accessory material. The percentage proportion of chemical components of the pre-melt material is as follows: 30 to 40 percent of CaO, 35 to 45 percent of SiO2, 3 to 10 percent of Al2O3, 1 to 5 percent of MgO, 4 to 8 percent of F, 6 to 12 percent of Na2, 0.5 to 3 percent of B2O3, and the rest is micro-impurity contained in the materials. The alkalinity, namely CaO/SiO2, of the pre-melt material is 0.70 to 1.05; the viscosity is 0.2 to 0.5Pa.s; and the pre-melt material is processed by pre-melting. The accessory material comprises 0.7 to 0.9 percent of simple-substance carbon and 0.25 to 1.5 percent of boron flame retardant, wherein a small part of the boron flame retardant is added in the form of borax and the majority of the boron materials is pre-melted into the pre-melt material; and the content of B2O3 in the pre-melted slag is 0.5 to 3 percent. The accessory material also comprises 0.2 to 0.8 percent of CaSi powder and 0.8 to 4.0 percent of manganese minerals. The high casting speed continuous casting covering slag not only can effectively reduce the carburetion of the covering slag to molten steel, but also can avoid negative impact on the metallurgical physicochemical property of the covering slag.

The present invention relates to a cracking furnace tube for retarding coking and carburizing of an ethylene cracking furnace tube, and a manufacturing method thereof. According to the present invention, the inner surface of the cracking furnace tube is provided with a layer of an oxide film, wherein the oxide film comprises at least one element selected from Cr, Ni, Fe, Mn, Al, Si and B; the manufacturing method comprises: directly adding at least one element selected from Al, Si or B to a nickel-chromium alloy containing elements of Cr, Ni, Fe, Mn and C during the conventional cracking furnace tube manufacturing process to prepare the tube, then carrying out a heat treatment for the resulting tube under low oxygen partial pressure atmosphere to generate a layer of the metal and/or nonmetal oxide thin film on the inner surface of the tube; when the cracking furnace tube of the present invention is adopted for producing olefin with low carbon number by the petroleum hydrocarbon cracking furnace, the deposition of the coke on the inner wall of the furnace tube can be reduced by more than 70%.

The invention discloses a powder catalyst for synthesizing ultrafine granular diamond. The powder catalyst is mainly prepared from the following alloying components by weight percent: 20% to 25% of Fe, 3% to 5% of Co, 0.5% to 2% of Ce, 3% to 5% of Mn, 0.5% to 1% of SiC, 0.5% to 1% of Mo and the balance being Ni. By utilizing the technical scheme of the powder catalyst, the high-purity ultrafine-particle spherical or approximately spherical powder catalyst can be prepared, and the granularity of the obtained powder catalyst is 600 to 1000 meshes. When the powder catalyst is applied to synthesis of ultrafine diamond single crystal, single-crystal diamonds within 400 meshes can be produced.

The invention provides a tundish covering agent for continuous casting of low-carbon steel containing Al and Ti and an application thereof. The tundish covering agent is prepared from, by mass, 32%-43% of CaO, 7%-14% of SiO2, 25%-32% of Al2O3, 6%-14% of MgO, 6%-13% of (Na2O+Li2O), 3%-7% of B2O3, 0.5%-1.5% of C and 1.1%-2% of TiO2. The tundish covering agent is low in melting temperature and viscosity and high in alkalinity. The tundish covering agent has the advantages that the tundish covering agent is suitable for continuous casting of the low-carbon steel containing Al and Ti, the mass percentage of C is smaller than or equal to 0.1%, the content of Al is smaller than or equal to 0.5%, and the content of Ti is smaller than or equal to 0.5%, inclusions in the low-carbon steel containing Al and Ti can be efficiently absorbed, the cleanliness of molten steel in a tundish is increased, secondary oxidation of the molten steel is well avoided, recarburization is avoided, the quality of a casting blank is improved, and meanwhile good thermal insulation performance is achieved.

The invention relates to a gas-based shaft furnace reducing system. The system comprises a gas-based shaft furnace, a cooling gas supply system and a reducing gas supply system, wherein the cooling gas supply system is used for preparing water vapor and desulfurated natural gas into cooling gas with main components of methane and water, and conveying the cooling gas to the gas-based shaft furnace;and the reducing gas supply system is used for treating cooling tail gas used by the gas-based shaft furnace to obtain reducing gas with carbon monoxide and hydrogen gas as main components, and conveying reducing gas to the gas-based shaft furnace. The invention further relates to a method for reducing and cooling metallized pellets. According to the system and the method disclosed by the invention, methane and water vapor in cooling gas have reforming reaction to generate CO and H2 under catalytic action of hot-stated metallized pellets (also can be ferrugination pellets), the reaction is remarkable in heat absorbing effect, retention time, at a cooling section of the gas-based shaft furnace, of the metallized pellets is remarkably shortened, dosage of cooling gas is also remarkably reduced, and compaction and production efficiency improvement of a shaft furnace body are facilitated.

The invention belongs to the technical field of cyanide-free copper plating technology, and particularly relates to a preparation method of an HEDP copper-plated non-porous thin layer. The preparation method comprises the steps that abrasive paper is used for polishing to remove floating rust at first, then, chemical degreasing and activation are carried out, and finally deionized water is used for cleaning; a plating solution is prepared; plating is carried out, particularly, an electrolysis copper plate is used as an anode, an oxidation film on the surface of the copper plate is removed, activation treatment is carried out for 5-10 s through a 10%-20% dilute hydrochloric acid solution, a base plate which is treated is used as a cathode to be placed in the plating solution, the temperature is 50-65 DEG C, the pH value is 9-11, direct current plating is carried out, the current density is 0.5-3.5 A/dm<2>, plating is carried out under the cathode moving condition, the moving speed is 3 cm/s-5 cm/s, and the HEDP copper-plated non-porous thin layer is obtained. The HEDP alkaline plating solution is low in toxicity, environmentally friendly and quite low in corrosion to production equipment, the leveling ability, dispersing ability and deep plating ability of the HEDP alkaline plating solution can reach or even exceed those of a cyanide copper plating solution, the cathode current efficiency reaches up to 95% or above, and the plating solution is stable in performance.

The invention relates to an unburned magnesium-calcium zirconate brick not containing free carbon. The unburned magnesium-calcium zirconate brick comprises the following raw materials in parts by weight: 10-20 parts of 97 fused magnesite with the granularity of more than 0 and less than or equal to 1 mm (0-1 mm), 25-35 parts of 200-mesh 97 fused magnesite fine powder, 10-20 parts of 20 calcium magnesium sand with the granularity of more than 1 mm and less than or equal to 3 mm (1-3 mm), 10-15 parts of 20 calcium magnesium sand with the granularity of more than 3 mm and less than or equal to 5 mm (3-5 mm), 5-15 parts of rotary kiln calcium magnesium sand with the granularity of more than 0 and less than or equal to 1 mm (0-1 mm), 5-15 parts of rotary kiln calcium magnesium sand with the granularity of more than 1 mm and less than or equal to 3 mm (1-3 mm), 5-15 parts of rotary kiln calcium magnesium sand with the granularity of more than 3 mm and less than or equal to 5 mm (3-5 mm), 0-3 parts of fused zirconia micro-powder, 0-2 parts of high-temperature asphalt powder and 2-4 parts of a binder. Two calcium magnesium sands with different heat expansion coefficient high-temperature properties are compounded to facilitate prolonging the service life of a refractory material. No graphite is not added, and no free carbon is contained, so that carburetion to molten steel is minimized.

Provided is a bimetallic tube for transport of hydrocarbon feedstocks in refinery process furnaces, and more particularly in furnace radiant coils, including: i) an outer tube layer being formed from stainless steels including chromium in the range of 15.0 to 26.0 wt.% based on the total weight of the stainless steel; ii) an inner tube layer being formed from an alumina forming bulk alloy including 5.0 to 10.0 wt.% of AL 20.0 wt.% to 25.0 wt.% Cr, less than 0.4 wt.% Si, and at least 35.0 wt.% Fe with the balance being Ni, wherein the inner tube layer is formed plasma powder welding the alumina forming bulk alloy on the inner surface of the outer tube layer; and iii) an oxide layer formed on the surface of the inner tube layer, wherein the oxide layer is substantially comprised of alumina, chromia, silica, mullite, spinels, or mixtures thereof. Also provided are methods of making and using the bimetallic tube.

The invention provides an oxidation-resistant coking-resistant hydrocarbon cracking furnace pipe and a preparation method thereof. A cracking furnace pipe is used as a barrel-shaped cathode, a molybdenum elementary substance, a silicon elementary substance and a modified material are put into the barrel-shaped cathode, through a glow discharge principle, molybdenum ions, silicon ions and modified substance ions are formed, and a MoSi2-modified substance composite permeable layer is formed on the inner surface of the cracking furnace pipe. The permeable layer can reduce high temperature oxidation and carburization of the cracking furnace pipe, reduce deposition of coke on the inner surface of the cracking furnace pipe in a hydrocarbon steam-cracking process, and obviously prolongs an operation period and a use life.

The invention discloses an eliminating type coke oven afterheat recovery power generating system based on a voltage stabilizing power supply circuit. The eliminating type coke oven afterheat recovery power generating system mainly consists of a coke oven top big pit and an oven top cylinder brick covering the top surface of the coke oven top big pit, wherein a perforated steel plate, a heat insulation plate layer and a perforated steel plate are sequentially arranged inside the coke oven top big pit from bottom to top, a heat insulation brick layer arranged between the perforated steel plate and the heat insulation plate layer is formed by filling heat-resistant sealing slurry in an inside gap part of the coke oven top big pit, a heat exchanger and an evaporator forming a sealed loop are arranged outside the coke oven top big pit, an afterheat power generating system is also arranged on the evaporator, an afterheat control circuit is arranged in the afterheat power generating system, a static electricity eliminating circuit, an overcurrent protection circuit, a control type power supply circuit, a voltage stabilizing power supply circuit and a control type output circuit are arranged in the afterheat control circuit, and the overcurrent protection circuit, the control type power supply circuit, the voltage stabilizing power supply circuit and the control type output circuit are in sequential connection.

Provided is a bimetallic tube for transport of hydrocarbon feedstocks in refinery process furnaces, and more particularly in furnace radiant coils, including: i) an outer tube layer being formed from stainless steels including chromium in the range of 15.0 to 26.0 wt.% based on the total weight of the stainless steel; ii) an inner tube layer being formed from an alumina forming bulk alloy including 5.0 to 10.0 wt.% of Al, 20.0 wt.% to 25.0 wt.% Cr, less than 0.4 wt.% Si, and at least 35.0 wt.% Fe with the balance being Ni, wherein the inner tube layer is formed plasma powder welding the alumina forming bulk alloy on the inner surface of the outer tube layer; and iii) an oxide layer formed on the surface of the inner tube layer, wherein the oxide layer is substantially comprised of alumina, chromia, silica, mullite, spinels, or mixtures thereof. Also provided are methods of making and using the bimetallic tube.

The invention discloses a current source feedback type waste heat generating system based on blast furnace superconducting cooling. The current source feedback type waste heat generating system based on the blast furnace superconducting cooling mainly comprises a blast furnace body (1), an electrical power generating system (12), a steam utilizing device, more than one superconducting annular heat exchange ring (2) which is hierarchically arranged along the side wall of the blast furnace body (1) in a surrounding manner and a waste heat control treatment system. The current source feedback type waste heat generating system based on the blast furnace superconducting cooling has the advantages that hot water after heat exchange is discharged in a concentrated manner by virtue of the superconducting annular heat exchange rings which are embedded in the side wall of the blast body and a corresponding annular pipeline system, so that heat exchange intensity is improved, heat exchange efficiency and cooling efficiency are improved; and temperature of the traditional cooling water is increased to 250 DEG C from 40 DEG C, and then the traditional cooling water is overheated to 400 DEG C by applying the superconducting heat exchange rings twice, so that cooling waste used for power generation is realized.

The invention discloses a blast furnace superconductive cooling waste heat power generation system based on a bias adjustable current source. The system is mainly formed by a blast furnace body (1), a power generation system (12), a steam utilization device, more than one superconductive annular heat transfer ring (2) in layered encircling arrangement along the side wall of the blast furnace body (1), pouring solidification bodies (10) made of wear-resisting heat-shock-resistant anti-permeability coal elastic refractory castables and arranged on each superconductive annular heat transfer ring (2), and lower conduits (32) connected in series with a lower circulation port of each superconductive annular heat transfer ring (2). According to the system, hot water obtained after heat transfer is exported in a concentrated manner through the superconductive annular heat transfer rings embedded in the side wall of the blast furnace body and annular pipeline systems corresponding to the superconductive annular heat transfer rings, so that heat transfer intensity is enhanced, heat transfer efficiency and cooling efficiency are improved, and cooling water temperature is improved from the original 40 DEG C to 250 DEG C; and then, the water is overheated to a temperature of 400 DEG C through twice applications of the superconductive annular heat transfer rings, and thus the cooling waste heat is allowed to be utilized for power generation.

A carbonaceous support member for a high-temperature heat-treated metal molding object, particularly a setter for heat-treatment in powder metallurgy, is formed as a carbon-ceramic composite shaped product having a bulk density of 1.2-1.6 g/ml and including a carbonaceous matrix and 3-20 wt. % of ceramic particles which are uniformly dispersed in the carbonaceous matrix and partly exposed to the surface of the composite. The support member can effectively prevent carburization of a metal molding object supported thereby during the heat-treatment without causing a problem of peeling of coating layer as encountered in a ceramic-coated support member. The support member may be prepared by compression molding of a powdery mixture of a fine carbon precursor and ceramic particles, followed by heating at 1000-2000° C. to carbonize the fine carbon precursor.

The invention discloses a protection type coke oven waste heat recovery power generation system based on a boost power supply circuit. The system is mainly composed of a coke oven top large pit and oven top quarry tiles covering the surface of the top of the coke oven top large pit. A porose steel plate, a heat insulation plate layer and a porose steel plate are sequentially arranged in the coke oven top large pit from bottom to top. Heat preservation brick layers between the porose steel plates and the heat insulation plate layer are formed by filling the inner gaps inside the coke oven top large pit with heat-resisting sealing slurry. A heat exchanger and an evaporator which form a closed loop are arranged outside the coke oven top large pit. A waste heat power generation system is arranged on the evaporator. A waste heat control circuit is arranged in the waste heat power generation system. An over-current protection circuit, a control type power supply circuit, the boost power supply circuit and a control type output circuit are connected in sequence and arranged in the waste heat control circuit.

The invention discloses a coke oven top waste heat recycling and electricity generation system based on an efficient drive power source circuit. The coke oven top waste heat recycling and electricity generation system is mainly composed of a large coke oven top pit and oven top quarry tiles covering the surface of the top of the pit. The large coke oven top pit is internally and sequentially provided with a porous steel plate, a heat insulation plate layer and the porous steel plate from bottom to top. A heat preservation tile layer arranged between the porous steel plates and the heat insulation plate layer is formed by pouring heat-resisting sealing slurry into seams of the large coke oven top pit. A heat exchanger and an evaporator for forming a sealing loop are arranged outside the large coke oven top pit. The evaporator is further provided with a waste heat electricity generation system. The waste heat electricity generation system is internally provided with a waste heat control circuit. The waste heat control circuit is internally provided with a control type power circuit, the efficient drive power source circuit, and a control type output circuit which are sequentially connected.

The invention discloses an alarm type coke oven waste heat recovery power generation system based on a power supply adjustment circuit. The system is mainly formed by a coke oven top large pit and oven top clinker tiles which cover the top surface of the coke oven top large pit. The internal part of the coke oven top large pit is orderly provided with a perforated steel plate, a heat insulation plate layer and a perforated steel plate from bottom to top. A heat preservation tile layer arranged between the perforated steel plate and the heat insulation plate layer, and the internal gap of the coke oven top large pit is filled with heat resistant sealing slurry. The external part of the coke oven top large pit is provided with a heat exchanger and an evaporator to form a closed loop. The evaporator is provided with a waste heat power generation system which is internally provided with a waste heat control circuit. The waste heat control circuit is internally provided with a power-off alarm circuit and is also provided with an overcurrent protection circuit, a control type power supply circuit, a power supply adjustment circuit and a control type output circuit which are connected in order.