31results about How to "Slow down the speed of coking" patented technology

The invention provides a method for producing aromatics and light oil by catalytic conversion of straight-run diesel oil. The method comprises the following steps: 1) performing pretreatment on straight-run diesel oil to remove basic nitrogen compounds to obtain straight-run diesel oil removed from basic nitrogen compounds; 2) adding transition metal ions to the straight-run diesel oil removed from basic nitrogen compounds The modified nanometer ZSM‑5 molecular sieve catalyst is used as a reaction catalyst to carry out a catalytic conversion reaction to obtain the aromatic hydrocarbons and light oil. In the present invention, the straight-run diesel oil from which basic nitrogen compounds have been removed is used as the reaction raw material, and the modified nanometer ZSM-5 molecular sieve is used as the catalyst to carry out the catalytic conversion reaction, the catalyst has high reactivity, the reaction is more sufficient, the conversion rate of diesel oil macromolecules is improved, and the target product of aromatic hydrocarbons is obtained. The yield is increased, the formation of dry gas by-products is suppressed, and the coking speed of the catalyst is slowed down to prolong the single-pass cycle.

The invention discloses a catalytic cracking and catalytic gasoline hydrogenation combined process. The process comprises: adjusting the operating conditions of an FCC (fluid catalytic cracking) device fractionating tower, and conducting cutting pre-separation on FCC gasoline in the fractionating tower to obtain light fractions and heavy fractions; subjecting the light fractions to alkali-free deodorization, then leaving the light fractions and thermocatalytic diesel oil to enter a hydrogenation prefractionator together to separate light gasoline and medium gasoline; and making the medium gasoline pass a prehydrogenation reactor and a hydrodesulfurization reactor in order to perform moderate selective hydrogenation, subjecting the heavy fractions to deep selective hydrogenation, and mixing the two parts of refined distillate oil with the refined light gasoline so as to obtain a clean gasoline product or a blending component. According to the process provided in the invention, the equipment energy consumption is reduced significantly, the gasoline octane number loss is small, and the gasoline product quality can meet quality requirement for a sulphur content of less than 10 micrograms / g, and the economic benefits of oil refining enterprises can be improved.

The invention discloses a low-energy consumption catalytic gasoline hydrodesulfurization method. The method comprises: adjusting the operating conditions of a catalytic device fractionating tower, conducting pre-separation on FCC (fluid catalytic cracking) gasoline in the fractionating tower so as to obtain light fractions at the tower top and heavy fractions at a lateral line; subjecting mercaptan in the light fractions to hydroconversion into a heavy sulfide, leaving the treated light fractions to enter a hydrogenation prefractionator to fractionate light gasoline and medium gasoline; carrying out moderate selective hydrodesulfurization on the medium gasoline, performing deep selective hydrodesulfurization on the heavy gasoline, subjecting the obtained two refined products to gas stripping, and then mixing them with the light gasoline undergoing mercaptan hydroconversion, thus obtaining a clean gasoline product. Compared with the existing catalytic gasoline hydrodesulfurization technologies, the method provided in the invention can significantly reduce equipment energy consumption, the gasoline octane number loss is small, the obtained gasoline product quality can meet the quality requirement of a sulfur content of less than 10 micrograms / g, and the economic benefits of oil refining enterprises are improved obviously.

The invention discloses a method used for catalytic gasoline deep hydrodesulfurization. The method comprises following steps: catalytic gasoline is delivered into a prefrationation tower firstly; an appropriate separation point is adopted, light gasoline fraction and middle gasoline fraction are discharged through the top of the prefrationation tower, and heavy gasoline fraction is discharged through the bottom of the prefrationation tower; the light gasoline fraction and the middle gasoline fraction are subjected to alkali-free deodorization, and are delivered into a hydrogenation prefrationation tower so as to separate light gasoline and middle gasoline, wherein catalytic cracking hot diesel oil extracted from a main fractionate tower side line is also delivered into the hydrogenation prefrationation tower; separated middle gasoline and heavy gasoline are mixed, and are subjected to selective hydrogenation, and an obtained distillate is mixed with light gasoline obtained via alkali-free deodorization so as to obtain clean gasoline products. Compared with existing catalytic gasoline hydrodesulfurization method, the method and equipment of the invention is capable of reducing energy consumption greatly, octane value loss of the gasoline products is less, sulfur content of the gasoline products is less than 10<mu>g / g, and economic benefits of oil refining enterprises are improved.

The invention provides a coking inhibitor capable of retarding the coking of a furnace tube, filler and a heat exchanger in the distillation process of waste oil and effectively prolonging the on-stream time. The coking inhibitor is fully utilized to soften coke blocks, inhibit condensation and polymerization of condensed aromatics, and prevent or reduce the formation of coking materials; after the product is added in the atmospheric and vacuum distillation process, an acid value is effectively reduced and acid corrosion of equipment is controlled; the coking speed is greatly reduced, and theon-stream time is prolonged, i.e., monthly maintenance is prolonged to three-month maintenance once, so that production days are increased, the input of maintenance cost is reduced and direct economicbenefits are brought for a factory.