41results about How to "Suitable process conditions" patented technology

The invention relates to a method for producing diesel oil through hydrogenation modification, modification, isomerization and decondensation of coal tar. Separating coal tar into residual oil and distillate oil, using distillate oil as raw material, adopting a single-stage or series process flow, under suitable operating conditions, distillate oil raw material and hydrogen pass through the catalyst bed to obtain low freezing point diesel products And a small amount of naphtha products with low sulfur and nitrogen content. It is characterized in that the catalyst bed includes a hydrogenation treatment catalyst bed containing 0.5-<20wt% of zeolite beta. The key point of this technology is that it can directly provide high-quality diesel products with low freezing point and high cetane number, and at the same time provide a suitable technological route for the rational application of coal tar.

The invention discloses a method for preparing a foamed aluminum alloy special-shaped piece with a uniform pore structure, which comprises the following steps: the first step: heating the aluminum alloy to melt, adding titanium hydride, stirring to disperse the titanium hydride, and then adding calcium to aluminum In the molten alloy, stir to increase the viscosity of the melt, cool the stirred melt to obtain a preform; the second step: put the above preform into the mold, heat it up, and keep it warm at this temperature, The primary foamed aluminum alloy prefabricated part is made into secondary foam in the mould, and the foamed aluminum alloy is cooled to obtain a foamed aluminum alloy product. In the second step, before the secondary foaming is heated up, the primary foamed aluminum alloy prefabricated part and the mold are preheated and kept warm. In the present invention, titanium hydride is added before the tackifier calcium is added, and the viscosity of the aluminum alloy melt is low, which is conducive to the uniform dispersion of titanium hydride in the aluminum alloy melt in a relatively short period of time, and is conducive to the preparation of a uniform pore structure. Dimensional foam aluminum alloy profiled parts.

The invention discloses a comprehensive utilization method of silicon carbide nucleation residue. The comprehensive utilization method comprises the following steps: S1, removing silicon carbide in the silicon carbide nucleation residue to obtain high-purity carbon material; S2, using the high-purity carbon material to make a filler of the thermal insulation structure; S3, arranging that heat preservation structure outside a silicon carbide nucleation crucible for heat preservation; S4, when the filler in the thermal insulation structure is eroded and cannot be used for thermal insulation, repeating the methods of steps S1-S4 on the eroded filler. The method of the invention realizes the secondary utilization of the nucleation residue, realizes the recycling use of the thermal insulation material on the premise of ensuring the consistency of the thermal insulation performance of the thermal insulation material, and saves the cost.

The invention discloses a hydrocracking start-up method, which includes the following contents: firstly, introducing low-nitrogen start-up oil, hydrogen and vulcanizing agent into the hydrocracking unit, and then performing constant temperature vulcanization on the hydrocracking catalyst under the condition of 220-260°C, After the hydrogen sulfide content in the circulating hydrogen reaches 3000-5000ppm, reduce the adding rate of the sulfiding agent and increase the bed temperature of the hydrocracking catalyst, and increase the adding rate of the sulfiding agent when the bed temperature of the hydrocracking catalyst reaches 310°C-330°C , after continuing the constant temperature vulcanization, raise the temperature to 380°C-390°C and feed the raw oil for reaction, wherein the hydrocracking catalyst contains 0.3%-4% nitrogen element by weight percentage, and the nitrogen element comes from low molecular nitrogen compounds and strongly basic cyclic nitrides. The method has the advantages of short time required for starting up, switching raw materials and entering a stable production state, avoiding the consumption of passivating agent during the starting process and the potential danger in the ammonia injection process, not only saving energy consumption, but also reducing the impact of passivating agent on the environment Pollution and harm to the human body.

The invention discloses a method for improving the operation safety of a hydrocracking unit. The hydrocracking unit contains at least two hydrocracking catalyst beds. When the nitrogen weight in the hydrocracking catalyst in the first hydrocracking catalyst bed is When the percentage content is 0.15~0.35%, cool down to 200~340°C to switch the hydrocracking feed oil with a nitrogen content of 300~500ppm, and switch the nitrogen content when the nitrogen content in the hydrocracking effluent is constant at 50~80ppm For hydrorefined oil less than 40ppm, adjust the reaction temperature of the hydrocracking section so that the mass yield of light oil <360°C is finally constant at 35~40%, and the total constant time is 48~96 hours, and then adjust to hydrocracking Reaction conditions The hydrocracking reaction is carried out. The method solves the problem that the activity of some hydrocracking catalysts is damaged due to frequent start-up and shutdown, thereby affecting the mismatch of reaction temperatures between different catalyst beds in the reactor.

The invention discloses a stable start-up method for a hydrocracking catalyst. In the start-up method, raw material oil is introduced during the vulcanization process, and the reaction temperature is adjusted after the vulcanization is completed so that the mass yield of light oil at <360°C is constant at 65-70%. Adjust to the hydrocracking reaction conditions to carry out the hydrocracking reaction, the hydrocracking catalyst contains 50%-70% molecular sieve by weight, and the molecular sieve includes but not limited to Y-type or USY molecular sieve. The method has the advantages of simple start-up and raw material switching process, stable operation, and avoids the consumption of passivating agent and the potential danger in the ammonia injection process during start-up.

The invention discloses a method for recovering the activity of a low-activity hydrogenation-modifying catalyst. The nitrogen content of 0-10 μg / g is introduced into the low-activity hydrogenation-modifying catalyst bed, and the reaction temperature of the reforming section is adjusted to < The mass yield of light oil at 175°C is constant at 20% to 30%, and the constant time is 24 to 48 hours. After the constant is over, it is adjusted to the hydrogenation upgrading condition for reaction; It contains 0%-less than 20% molecular sieve and 0.15%-0.35% nitrogen element, and the molecular sieve includes at least one of Y-type or USY molecular sieves. The method has the advantages of simple process and stable operation, and solves the problem of how to restore the activity reduction of the hydrogenation reforming catalyst caused by long-term operation in the hydrogenation refining mode.

The invention discloses a method for improving the stable operation of a hydrocracking unit. The hydrocracking unit contains at least two hydrocracking catalyst beds. When the nitrogen in the hydrocracking catalyst in the first hydrocracking catalyst bed is When the nitrogen content is 0.2~0.45%, the temperature is lowered to 200~340°C to switch the hydrocracking feed oil with a nitrogen content of 300~500ppm. When the nitrogen content in the hydrocracking effluent is constant at 50~80ppm, switch the nitrogen content to less than 20ppm of hydrorefined oil, while adjusting the reaction temperature of the hydrocracking section so that the mass yield of light oil <360°C is finally constant at 55~60%, and the constant time is 24~48 hours, and then adjusted to the hydrocracking reaction conditions carry out hydrocracking reactions. The method solves the problem that the activity of some hydrocracking catalysts is damaged due to frequent start-up and shutdown, thereby affecting the mismatch of reaction temperatures between different catalyst beds in the reactor.

The invention discloses a method for improving the operation safety of a hydrocracking unit. The hydrocracking unit contains at least two hydrocracking catalyst beds. When the nitrogen weight in the hydrocracking catalyst in the first hydrocracking catalyst bed is When the percentage content is 0.15~0.4%, lower the temperature to 200~340℃ and switch the hydrocracking feed oil with nitrogen content of 300~500ppm, and switch the nitrogen content when the nitrogen content in the hydrocracking effluent is constant at 50~80ppm For hydrorefined oil less than 30ppm, adjust the reaction temperature of the hydrocracking section so that the mass yield of light oil <360°C is finally constant at 45~50%, and the total constant time is 24~48 hours, and then adjust to hydrocracking Reaction conditions The hydrocracking reaction is carried out. The method solves the problem that the activity of some hydrocracking catalysts is damaged due to frequent start-up and shutdown, thereby affecting the mismatch of reaction temperatures between different catalyst beds in the reactor.

The invention discloses a method for recovering the activity of a low-activity hydrogenation upgrading catalyst. The method is as follows: feed refined oil with a nitrogen content of 0-10 μg / g into the low-activity hydrogenation upgrading catalyst bed, and at the same time adjust the reaction temperature in the upgrading section so that the mass yield of light oil at <175°C is constant at 40 % to 50%, the constant time is 24 to 48 hours, and after the constant is completed, adjust to the hydrogenation and upgrading conditions to react; the low activity hydrogenation and upgrading catalyst contains 50% to 70% of molecular sieves by weight, 0.25 % to 0.45% nitrogen, the molecular sieves include at least one of Y-type or USY molecular sieves. The method has the advantages of simple process and stable operation, and solves the problem of how to restore the activity reduction of the hydrogenation reforming catalyst.

The invention relates to a direct-spun black yarn FDY (full drawn yarn) processing process based on master batch injection melt, which sequentially comprises the steps of: PET (polyethylene terephthalate) melt preparation, black master batch preparation, sufficient mixing of melt and spinning. According to the invention, the technical defects in the prior art of yarn floating during spinning, many broken ends, easiness in web yarn generation, large chroma difference generated while stopping spinning, nonuniform melt blending and the like are solved, and the benefits of saving subsequent dyeing and other aftertreatment processes, saving energy, reducing white slab transportation and fusion processes, saving a great deal energy, and realizing large-scale production of FDY black yarn with no filament breakage, low elasticity and excellent quality are achieved.