11 results about "Contact process" patented technology

The application provides a method for rapidly preparing battery-grade iron phosphate by microwave heating, which comprises the following steps: adding iron powder into a phosphoric acid solution, adjusting pH after the iron powder is dissolved, collecting filtrate and heating to a set temperature range; carrying out oxidation reaction on the collected filtrate and an oxidizing agent, pumping the obtained reaction slurry into a tubular reactor for microwave heating reaction; filtering and washing the obtained product, and drying the filter cake after the washing by microwave to obtain hydrous iron phosphate; and calcining the obtained dihydrate iron phosphate after ball milling to obtain battery-grade anhydrous iron phosphate. The application adopts a combination of a kettle reactor and a tubular reactor for reaction, the kettle reactor buffers the violent reaction in the initial contact process of the material, and reduces the particle size of the primary reaction; the tubular reactor enables the material to be more fully contacted, further improves the crystal structure of the material, and improves the conversion rate of the material.

The invention discloses a turbulent flow catalytic device and a preparation method thereof, a cracking furnace and a vacuum coating machine, and the turbulent flow catalytic device comprises a plurality of connecting pieces which are arranged in a cracking pipe and are parallel to each other; the connecting piece extends in the axial direction of the cracking pipe; at least one solid panel; the solid panel is connected with each connecting piece; a gap is formed between the periphery of the solid panel and the inner wall of the cracking pipe to form a first airflow channel; the at least one annular plate is coaxially arranged in the cracking pipe; the outer circumferential face of the annular plate is attached to the inner wall of the cracking pipe so that a second airflow channel can be formed in the center hole of the annular plate. The paths of airflow passing through the two airflow channels are not continuous or parallel, and gas flow lines are extruded and guided to different directions for multiple times, so that heat exchange is enhanced, and the original laminar flow state is broken; the gas can also make physical contact with a catalyst layer on the surface of the plate, it is guaranteed that more raw materials are cracked or activated in the contact process, activation energy needed by the reaction is reduced, and therefore the cracking temperature is reduced.

The invention discloses a cyclic utilization method of a magnesium element in laterite-nickel ore hydrometallurgy. The method comprises the following steps: atomizing the magnesium sulfate-containing waste liquid obtained in the laterite-nickel ore hydrometallurgy process, and pyrolyzing in a reducing atmosphere to obtain magnesium oxide powder and SO2-containing gas; the method comprises the following steps: regulating magnesium oxide powder to obtain magnesium slurry, returning the magnesium slurry to a leaching solution containing Ni < 2 + > and Co < 2 + > at the front end of laterite-nickel ore hydrometallurgy, and carrying out a nickel cobalt hydroxide precipitation reaction; the SO2-containing gas is dedusted and dried, and concentrated sulfuric acid is prepared by adopting a two-conversion and two-absorption contact method. According to the method, the magnesium-containing waste liquid is subjected to spray pyrolysis, and obtained magnesium oxide and SO2 are respectively fed into a laterite-nickel ore hydrometallurgy production line and an acid making production line, so that not only is zero emission of the magnesium-containing waste liquid realized, but also resource cyclic utilization of the magnesium element is effectively realized, and the method is suitable for industrial production. The technical problems that in the prior art, magnesium-containing waste liquid in laterite-nickel ore hydrometallurgy is high in treatment cost and difficult to recycle are effectively solved.

The invention discloses a preparation process and a preparation system for preparing sulfuric acid by a contact method, which are characterized in that pyrite and smelting flue gas are used as preparation raw materials, and when a production system is started again, the temperature of a gas inlet of a sulfur trioxide conversion section can be increased to 400 DEG C or above within 8 hours, so that the requirement of sulfur dioxide gas inlet is met, and time and energy can be saved; and the furnace lifting efficiency of the roasting furnace can be improved, the air inducing amount can be increased, the air amount control flexibility can be improved, and the roasting furnace can adapt to the air inducing amount in a wider proportion range.

The invention relates to the technical field of ventilation equipment, in particular to a pulverized coal pipeline anti-deposition device based on a cyclone, which comprises a cyclone body, a filter assembly, a cleaning assembly and a driving assembly, the cleaning assembly comprises a cleaning brush, and the driving assembly is used for driving the cleaning brush to intermittently contact with a filter plate. In the contact process, the cleaning brush is driven to rotate in the circumferential direction for cleaning; the cleaning brush which can be intermittently close to the filter plate is used for cleaning the filter plate, the situation that the cleaning brush is continuously contacted and abraded with the filter plate for a long time, and consequently the cleaning brush is seriously worn is avoided, the service life of the cleaning brush is prolonged, the cleaning brush is intermittently cleaned in the ventilation process, ventilation operation is not affected, and the ventilation efficiency is improved. Cleaning work is not needed after ventilation work is stopped, so that continuous ventilation work is guaranteed, in the process that the cleaning brush gets close to the filter plate, the cleaning head of the cleaning brush can stretch into the filter holes of the filter plate to push out dust in the filter holes, and then the cleaning effect is further improved.

The invention provides a vanadium catalyst with high hydrothermal stability as well as a preparation method and application thereof. The vanadium catalyst with high hydrothermal stability is prepared from the following raw materials in percentage by weight: 80-90% of a modified diatomite carrier, 7-8.5% of an active component and 1.5-9.0% of a compound functional aid, modified diatomite is used as a carrier, a compound functional aid is added into active components, mixing molding and segmented roasting are performed, the prepared catalyst is suitable for a wet contact method acid preparation process containing 8-20% of H2O and SO2 with the volume fraction of 10% + / -1%, the SO2 conversion rate at 410 DEG C is larger than or equal to 110% (based on 100% of a traditional catalyst), the acid soaking strength is larger than or equal to 45 N / cm, the hydrolysis inactivation rate is reduced by larger than or equal to 60%, and the vanadium leaching amount lt is achieved; the catalyst has the advantages of high activity, excellent pulverization resistance and low cost, the service life of the catalyst can be more than two times that of a traditional catalyst, and the industrial application prospect is wide.

The invention discloses an impurity detection method for a device for granular silicon production in the field of preparation of high-purity monatomic silicon products, and aims to solve the technical problem that large or irregular devices cannot be moved into a laboratory for destructive detection. The method comprises the following steps: soaking and cleaning a silicon block to be rubbed in a soaking solution with a certain volume ratio; cleaning a preset area on the surface of the to-be-tested device, enabling the soaked and cleaned silicon block to be in frictional contact with the preset area, soaking the rubbed silicon block and a blank silicon block which is not rubbed respectively, preparing solutions, and detecting the concentration of metal impurity elements in each solution; and calculating the content of the impurities introduced by the friction of the surface of the to-be-detected device according to the concentration detection result of each metal impurity element in the rubbed silicon block solution and the blank silicon block solution. According to the invention, in-situ and non-destructive detection of large and immovable tools and devices can be realized, and the surface impurity release level of the large and immovable tools and devices can be accurately evaluated by simulating the actual contact process.

To provide a magnetic disc substrate polishing method that enables halation reduction by achieving adjustment of a carrier circumferential speed of a carrier at time of polishing and a polishing agent composition used for the polishing.SOLUTION: A polishing method 1 for polishing a magnetic disc substrate using a polishing agent composition and a polishing machine includes: a polishing agent composition preparation process S1 of preparing a polishing agent composition; and a polishing process S2 including a pad surface contact process of bringing a pad surface into contact with a substrate surface, a polishing agent composition supply process of supplying the polishing agent composition, a rotation process of rotating a flat plate and a polishing pad, and a planetary motion process of causing a carrier 5 fitted to the magnetic disc substrate to perform planetary motion. The polishing agent composition used for the polishing contains at least colloidal silica, acids, and oxidizing agents, a value of pH (25°C) is in a range between 1.3 or more and 4.0 or less, and a content of sulfuric acid in acid composing the polishing agent composition is 0% by mass or more and 1.0% by mass or less.SELECTED DRAWING: Figure 1

This invention relates to the synthesis of methyl thioglycolate, and discloses a method and apparatus for the continuous flow synthesis of methyl thioglycolate, as well as its applications. The method includes: introducing a catalyst, methyl thioglycolate, and methanol into a micromixer for contact; introducing the resulting feedstock into a microreactor for reaction; subjecting the resulting reaction solution to a first vacuum distillation to obtain an overhead effluent and a bottom effluent; heating the overhead effluent and then subjecting it to atmospheric distillation to obtain a methanol effluent and a wastewater effluent; refluxing the methanol effluent for the contact process; heating the bottom effluent and then subjecting it to a second vacuum distillation to obtain a methyl thioglycolate product and a feedstock effluent; cooling the feedstock effluent and then refluxing for the contact process; the feedstock effluent contains unreacted methyl thioglycolate and catalyst. This method and apparatus enable the continuous preparation of methyl thioglycolate, allowing for the reuse of feedstock and catalyst, resulting in a short reaction time, minimal environmental pollution, and high purity, yield, and selectivity of the methyl thioglycolate product.

An integrated chemical process for the production of sulfuric acid is described, that combines a process of producing sulfuric acid from SO2, and a process of producing hydrogen and SO2 from the reaction of hydrogen sulfide, iodine and water. Sulfur dioxide produced from this process is first separated from the liquid effluent using a flash separation process. The resulting sulfur dioxide stream can be purified using an absorber or adsorber unit. The sulfur dioxide is then diluted with air to the desired stoichiometric conditions and fed into a sulfuric acid reactor. This reactor can consist of a contact process, wet sulfuric acid process, or sulfur electrolysis process. The effluent of this reactor is concentrated sulfuric acid, which is a valuable commodity chemical.

The invention provides an electrolytic copper foil anti-oxidation tank, which belongs to the technical field of copper foil processing and comprises an adjusting tank, a reaction tank, a water distributor, a positioning mechanism, a tensioning mechanism and a liquid removing mechanism. Wherein the adjusting tank comprises a containing cavity, and the containing cavity provides a flowing space for anti-oxidation liquid; the reaction tank is vertically arranged on the adjusting tank, the reaction tank comprises a feeding end and a discharging end, and the copper foil is vertically unfolded to pass through the reaction tank; the water distributor is arranged at the bottom, close to the reaction tank, of the adjusting tank in a long strip shape, and the water distributor sprays anti-oxidation liquid from bottom to top to form a water curtain; the two positioning mechanisms are arranged at the feeding end and the discharging end of the reaction tank, and each positioning mechanism is used for clamping and positioning the copper foil. According to the device, the anti-oxidation liquid can be fully and uniformly contacted with the copper foil, the probability of generation of impurities and bubbles in the contact process is reduced, and the anti-oxidation quality of the copper foil is improved.