146 results about "Acid concentration" patented technology

The utility model discloses a waste acid concentration and recovery device, which relates to the technical field of waste acid recovery, and comprises a flocculation barrel and a heating barrel, and further comprises a disturbance impurity removal unit and a transfer filtering unit which are arranged between the flocculation barrel and the heating barrel, the disturbance impurity removal unit comprises a collection hopper, an impurity removal vertical pipe, a rotating rod, a driving motor, a disturbance transverse plate and a spiral blade; the adjusting and filtering unit comprises a circular brush plate, a servo motor, a screw rod, a flocculating agent input pipe and a circular filter plate. In the utility model, the disturbance transverse plate fixedly arranged on the peripheral surface of the rotating rod can disturb and stir waste acid and a flocculating agent, flocculate is extruded by the circular filter plate and then is gathered through the aggregate bin, and when the flocculate is removed, a pipe plug on the impurity removal vertical pipe is taken down, so that the waste acid and the flocculating agent can be removed. And the spiral blade wound on the peripheral surface of the rotating rod can push and guide out the gathered flocculate on the impurity removal vertical pipe to complete removal, so that the flocculate is smoothly discharged and guided out, and the subsequent treatment effect is ensured.

Disclosed in the present invention is a process for preparing a monosaccharide solution by means of acid gradient treatment of a straw lignocellulose. The process comprises the steps of: S1: performing a first acidolysis reaction on a lignocellulose biomass using an acid solution with a concentration of 50 wt% or above to obtain a first acidolysis solution; S2: uniformly mixing the first acidolysis solution with an organic solvent, and performing solid-liquid separation to obtain a glycan-containing residue; and S3: adding water and / or an acid solution to the glycan-containing residue to obtain a mixed solution with an acid concentration of 45 wt% or below, and performing a second acidolysis reaction to obtain a monosaccharide-containing reaction solution. In the present invention, pretreatment is performed at room temperature and atmospheric pressure without the need to provide additional energy, and various agents used in the pretreatment process are all recoverable, which greatly reduces the production cost. In addition, in the present invention, a relatively low liquid-solid ratio is used, monosaccharide can be directly obtained after the pretreatment, and finally a monosaccharide solution with a high and adjustable concentration is obtained, thereby avoiding a large amount of input in enzyme costs.

The invention discloses an establishing method, a monitoring method and an adding method of a monitoring model for the concentration of hydrochloric acid in an etching solution. The establishing method of the monitoring model for the concentration of hydrochloric acid in the etching solution comprises the following steps: acquiring sample data; calculating each coefficient value in a pre-established multivariate polynomial regression model according to the sample data to obtain a regression model; obtaining verification data, taking the temperature, the oxidation-reduction potential, the hydrochloric acid concentration and the Cu < 2 + > concentration in the verification data as the input of the regression model, and outputting the predicted value of the conductivity; calculating the closeness degree of the predicted value of the conductivity and the actual value of the conductivity in the verification data; when the calculated closeness degree is smaller than a preset threshold value, recalculating each coefficient value in the regression model until the closeness degree is greater than or equal to the preset threshold value; and when the calculated closeness degree is greater than or equal to a preset threshold value, taking the obtained regression model as a hydrochloric acid concentration monitoring model.

The utility model belongs to the technical field of heat exchanger cleaning, and discloses a heat exchanger cleaning device which comprises a box body, a circulating system and an acidity meter, acid liquid is contained in the box body, the circulating system is connected with the box body and a heat exchanger and can enable the acid liquid in the box body to enter the heat exchanger in a circulating mode, and the acidity meter comprises a probe and a display screen. The probe is arranged in the box body and used for detecting the concentration of the acid liquid in the box body, and the display screen is used for displaying the real-time acid concentration of the acid liquid. According to the heat exchanger cleaning device provided by the utility model, the acid liquid is used for circularly cleaning the heat exchanger, so that the heat exchanger is prevented from being disassembled and assembled, and the working difficulty of workers is reduced; it is ensured that the acid liquid can chemically react with scale every time the acid liquid enters and exits the heat exchanger, effective cleaning is achieved every time the acid liquid enters and exits the heat exchanger, and the cleaning efficiency of the heat exchanger is effectively improved.

The invention discloses a resourceful treatment method for stainless steel pickling waste liquid and waste water. The waste liquid is divided into high-concentration waste liquid and low-concentration waste liquid according to the acid concentration and the salt concentration to be treated respectively. Sequentially recovering gypsum, chromic hydroxide, nickel sulfide, ferrous hydroxide and manganese-rich slag from the low-concentration waste liquid through gradient precipitation; and neutralizing free acid from the high-concentration waste liquid by using ferrous hydroxide generated in a low-concentration section, cooling and crystallizing to recover ferrous sulfate, deeply removing nickel by using nickel sulfide generated in the low-concentration section, and precipitating to recover chromium hydroxide. In the whole process, generation of ferric iron is strictly controlled, and high-value productization recovery of free acid and all metals is achieved. The method has the advantages of low medicament consumption, high metal recovery rate, high product value, no secondary pollution and the like.

Proposed is a method for producing a grain-oriented electromagnetic steel sheet, with which it is possible to further improve magnetic properties and suppress fluctuations in magnetic properties and film properties in a coil without using an inhibitor. This method for producing a grain-oriented electromagnetic steel sheet includes: a hot rolling step for hot rolling a steel roll material having a constituent composition which contains C, Si, Mn, acid-soluble Al, N and Sb and in which S and Se are contained so as to satisfy a prescribed relational expression; an optional hot-rolled sheet annealing step; a cold rolling step; an acid washing step; a primary recrystallization annealing step; and a finish annealing step. In intermediate annealing in the hot-rolled sheet annealing step or cold rolling step before a final cold rolled steel sheet is obtained, the γ-phase fraction in the steel structure at the annealing temperature is 1.0-25.0 vol%, the average cooling speed after annealing is 20-50ºC / s, acid washing is carried out using a solution which contains 2-15 mass% of Fe ions and has an acid concentration of 1-20 mass% in the acid washing step, and an annealing separating agent contains a Ti compound at a quantity of 0.3-8 parts by mass in terms of Ti relative to 100 parts by mass of magnesia in the finish annealing step.

This invention relates to the field of scheelite processing technology, and particularly to a method for processing scheelite ore, comprising the following steps: first, slurry conditioning; pH adjustment, the method for controlling the pH value of the reaction solution includes: after controlling the reaction solution to a first pH value, lowering the pH value to a second pH value every first time period, and finally controlling the residual acid concentration of the reaction solution to be controlled at 8-11 g / L and maintained for a second time period; first filtration; second slurry conditioning; leaching; second filtration. Using the scheelite ore processing method provided by this invention, after treating the scheelite ore with a first reagent under certain conditions, followed by leaching treatment, effectively reduces the tungsten content in the slag and reduces tungsten loss. This method has the advantages of a short process, less reagent addition, less slag and solution formation, and significantly reduced tungsten loss.

The invention relates to a weighted authigenic acid as well as a preparation method and application thereof. The weighted authigenic acid comprises an acid generating component and a weighting component, the acid generating component comprises an acid generating agent, a product solubilizer, a catalyst and a corrosion inhibitor; the acid generator comprises organic weak acid and a chlorine-containing acid generator; the weighting component comprises weighting salt, a resistance reducing agent and water; the aggravated authigenic acid is high in acid generation efficiency and controllable in acid generation concentration, the concentration of generated H < + > can reach up to 4.95 mol / L, the aggravated authigenic acid has high corrosion inhibition capacity, the corrosion rate is as low as 30 g / (m < 2 >. H) or below, the preparation method is simple, raw materials are easy to obtain, and the aggravated authigenic acid can be used for efficient transformation of ultra-deep high-temperature carbonate reservoirs with the temperature reaching up to 120-200 DEG C.

The invention belongs to the technical field of biological detection, and particularly relates to active powder for rapidly detecting the concentration of succinic acid, a detection device and a detection method, the detection process is simplified through standardized addition of the active powder, online monitoring of the concentration of succinic acid can be realized in combination with a matched detection device, the accuracy of a detection result is improved, and the detection efficiency is improved. Rapid detection of the concentration of succinic acid can be achieved, the concentration of succinic acid can be monitored on line in combination with a matched device, and the production efficiency and the product quality control level are greatly improved.

The invention provides a pickling line monitoring system, which comprises a sensor, a control module and an actuator, the sensor monitors the acid concentration, temperature, liquid level and pickling line transmission speed of a pickling tank, and the actuator is used for controlling the technological actions of acid supplement, acid dilution, acid discharge, heating and circulation of the pickling tank. The control module controls the actuator in real time according to data of the sensor so as to maintain the concentration of acid liquor in the pickling tank to be close to the optimal value of the pickling process; the real-time control strategy of the control module comprises the steps that output parameters of an actuator are adjusted in real time through a feed-forward control and PID feedback control integrated composite control strategy, feed-forward compensation is improved for the change of the transmission speed of the pickling line through feed-forward control, and disturbance of acid concentration, temperature and liquid level data to output is reduced through PID feedback control setting dead zones. According to the invention, the acid concentration adjusting precision and the automation degree of the pickling line are improved.

The invention discloses a titanium dioxide waste acid concentration system and method, and belongs to the technical field of sulfuric acid process titanium dioxide production or similar waste acid concentration. The system comprises a primary concentration and ferrous separation module and a secondary concentration and ferrous separation module. The primary concentration and ferrous separation module realizes primary concentration and solid-liquid separation of waste acid through an evaporation concentration kettle, a flash tank and a primary diaphragm filter press; and the secondary concentration and ferrous separation module is used for carrying out deep concentration and secondary separation on the waste acid through a scraper evaporator and a secondary diaphragm filter press. The system adopts the technologies of ultrasonic descaling, stepped concentration and solid removal, partition temperature control film evaporation and the like, and is matched with a mirror surface level inner wall scraper evaporator and an adjustable rapping device, so that the problem of scaling blockage in the waste acid concentration process is effectively solved. The method can increase the concentration of waste acid to 60% or above, realizes continuous automatic operation, and has the advantages of low equipment investment, low operation cost, environmental friendliness, high resource recovery rate and the like.

The invention relates to the field of phosphoric acid production, and particularly discloses an improved nitric acid method crude phosphoric acid production process and a denitration concentration system. The production process comprises the following steps: decomposing phosphorite with dilute nitric acid, freezing and crystallizing the obtained acidolysis solution, filtering, and adding concentrated sulfuric acid to obtain a mixed acid solution containing phosphoric acid and nitric acid; and introducing the mixed acid liquid into a first-effect evaporator and a second-effect evaporator for double-effect evaporation, and distilling in a rectifying tower to obtain a crude phosphoric acid product. According to the application, mixed acid is subjected to denitration concentration by adopting a downstream double-effect evaporation technology, by virtue of a pressure-temperature double-gradient design and in combination with a rectifying tower, staged denitration is realized by utilizing the pressure dependence of the volatility of nitric acid, and primary denitration and energy supply are realized by adopting a high-pressure and high-temperature evaporation section as a first-effect evaporation section; the second-effect evaporation is a vacuum low-temperature evaporation section, deep denitration and acid enrichment are achieved, and the concentration of nitric acid enriched in the low-temperature section reaches 55 wt%. The concentration of phosphoric acid in the finally obtained product is more than or equal to 75wt%, and the residual nitric acid is less than or equal to 0.5

The present application relates to the technical field of rhombohedral manganese ore leaching, and particularly discloses a rhombohedral manganese ore dressing and smelting combined efficient leaching process, which comprises the following steps: 1. low-acid leaching: rhombohedral manganese ore powder is added into low-acid anolyte for stirring leaching, the acid concentration of the anolyte is 42-46 g / L, 8-10 cubic meters of low-acid anolyte is used for each ton of rhombohedral manganese ore powder, after the leaching is completed, the end point pH value is controlled to be 6.0-6.5 by adding a neutralizing agent, and the leaching slurry is concentrated by a thickener to separate supernatant and concentrated ore slurry. The present application can efficiently realize rhombohedral manganese ore leaching and is suitable for promotion.

The invention relates to the field of chemical analysis and detection, in particular to a method for rapidly detecting the concentration of industrial concentrated acid based on neutralization reaction, which comprises the following steps: 1, theoretical calculation; converting molar concentration according to acid density and mass fraction; 2, accurately measuring the volume of target acid by using a pipette; 2, injecting 100-150ml of pure water into the triangular flask, and adding 3-5 drops of phenolphthalein; 3, slowly injecting an acid sample into the triangular flask, and slightly shaking and uniformly mixing; 4, adding 10.00 ml of NaOH solution by using the pipette, and oscillating for 10-20 seconds; 3, result interpretation: transparency and colorless: acid is excessive when the acid concentration reaches the standard, pH is less than or equal to 8.2 after neutralization, pink lasts for 20-30 seconds, and reinspection is needed when the acid concentration is insufficient and the pH is greater than or equal to 8.3. The method has the beneficial effects that 1, a reverse judgment method is adopted, namely the conventional end-point titration is replaced by fixed alkali amount, so that the detection time is shortened to 2 minutes; 2, safety design: pre-dilution reduces the risk of acid mist, and only a trace amount of raw acid is needed to avoid acid corrosion; 3, multi-acid adaptation: compatibility with detection of different types of concentrated acids is realized through pipetting volume adjustment;

This utility model belongs to the field of stainless steel pipe pickling technology, specifically relating to an acid concentration adaptive automatic pickling tank, including a tank body. A perforated plate is fixedly connected to the inner wall of the tank body. An acidity detector is embedded in the tank body. A sealing baffle is detachably connected to the tank body. A disturbance component is arranged below the perforated plate. A reflux component and a vibration component are arranged on the side wall of the tank body. The disturbance component includes a motor, which is fixedly mounted on a mounting frame. A bevel gear is fixedly connected to the output shaft of the motor. This acid concentration adaptive automatic pickling tank, through the use of the disturbance component, uses a motor to drive the agitator blades to rotate, agitating the acid solution. The reflux component, through synchronous transmission, rotates the spiral blades, transporting the acid solution from the bottom of the tank to the top, promoting the circulation and mixing of the upper and lower layers of acid solution, significantly reducing concentration stratification and avoiding excessive or insufficient acid replenishment due to local concentration deviations, thus ensuring stable pickling results.

The invention relates to the technical field of concentration detection of phosphate, in particular to a method for detecting the concentration of phosphate ions in a nickel-free hole sealing tank solution. The detection method comprises the following steps: adding a nickel-free hole sealing tank solution into a quantitative bottle for quantification, adding an ascorbic acid solution and a molybdate solution into a volumetric flask, carrying out a standing reaction at 28-32 DEG C for 15-25 min, determining the light absorption value of the reaction solution at 700 nm by using a spectrophotometer, obtaining the phosphorus content M according to a phosphorus standard curve model, and calculating the phosphate ion concentration P according to a formula. Compared with an existing method for detecting the concentration of orthophosphoric acid through IC equipment, the concentration data measured through the spectrophotometric method is more stable and smaller in difference, the accuracy of concentration analysis of the phosphate ions in the nickel-free hole sealing groove can be achieved, and the situation that materials are scrapped due to the fact that the concentration of the phosphate ions is abnormal in the production process is effectively avoided.

The invention discloses a rinsing system and a rinsing method for regulating and controlling the deacidification effect of a latex solidification film, the film to be rinsed is output from the right end of the system after sequentially passing through one to multiple stages of rinsing tanks, the acid content of the film is gradually reduced after multiple times of thinning and rinsing, and the acid content of circulating water in the rinsing tanks is also gradually reduced. Acid-free make-up water enters the system from an inlet of a make-up water pump in the rear-stage rinsing tank, sequentially passes through the rear-stage rinsing tank and the front-stage rinsing tank, and then is discharged from the front-stage rinsing tank; the distribution trend of the acid content of the make-up water is consistent with the distribution trend of the acid content of the circulating water from the previous-stage rinsing tank to the last-stage rinsing tank, and a large concentration difference is maintained between the make-up water and the circulating water in each tank, so that the deacidification effect of the make-up water is fully exerted, and the purpose of saving water is achieved. The acid concentration difference value between the make-up water and the circulating water in each tank can be changed by changing the flow of the make-up water, and the deacidification effect of the film is changed.

This invention belongs to the field of fly ash treatment technology, specifically disclosing a method for separating potassium and sodium from fly ash, including the following steps: adjusting the acid concentration in the fly ash washing solution to 40-65% and the temperature to 40-65℃, adding a sodium precipitating agent and maintaining the reaction temperature, and filtering to obtain sodium salt and potassium-containing waste liquid. This invention utilizes precipitation to recover sodium ions from fly ash washing solution. After filtration, sodium salt precipitate and potassium-containing waste liquid are obtained. During this process, the reaction is controlled under acidic conditions to prevent potassium ion precipitation. At 40-60℃, the sodium precipitating agent reacts with sodium ions to obtain sodium salt precipitate with large crystals, which allows for more convenient and thorough filtration, resulting in better separation of potassium and sodium ions in the fly ash washing solution. The sodium salt precipitate is further washed with a displacement agent to replace the potassium ions attached to the surface of the sodium salt precipitate with sodium, improving the purity of the sodium salt product. Finally, multiple water washings are performed to reduce the acidity of the sodium salt precipitate, resulting in a sodium salt product with stable quality.

Embodiments of the present technology include electroplating methods that include providing a first portion of an electrolyte feedstock to a first compartment of an electrochemical cell. The first portion of an electrolyte feedstock may be characterized by an initial metal ion concentration and an initial acid concentration. The methods may include providing a second portion of an electrolyte feedstock to a second compartment of the electrochemical cell. The second compartment and first compartment may be separated by a first membrane. The methods may include providing an acidic solution to a third compartment of the electrochemical cell. The third compartment and second compartment may be separated by a second membrane. The acidic solution may be characterized by an initial acid concentration. The methods may include applying a current to an anode of the electrochemical cell. The anode of the electrochemical cell may be disposed proximate the first compartment and across from the first membrane.

An electroplating system including a Cu bath disposed within a vessel, the Cu bath characterized by a predetermined threshold of Cu concentration, and a predetermined threshold of acid concentration, and where a substrate is submerged in the Cu bath; and a jet array configured to spray a fluid onto the substrate, where the fluid has a same composition as the Cu bath. Further, a method including spraying a fluid onto a substrate with the jet array, wherein the fluid has a same composition as the Cu bath and where spraying the substrate increases a deposition rate of a deposited Cu onto the substrate, where the predetermined threshold of acid concentration increases a bath conductivity of the Cu bath, and where the increased bath conductivity improves a coplanarity of deposited copper structure.

The utility model provides an automatic sulfuric acid concentration detection device which is characterized in that a liquid inlet pipe is arranged on one side of a shell, a sampling valve is arranged at the upper end of the liquid inlet pipe, a cavity with a closed structure is arranged at the upper half position of one side in the shell, and a first sulfuric acid concentration meter and a second sulfuric acid concentration meter are arranged in the cavity; the detection ends of the first sulfuric acid concentration meter and the second sulfuric acid concentration meter extend into the shell and are close to the bottom of the shell, a liquid level sensor is further arranged between the first sulfuric acid concentration meter and the second sulfuric acid concentration meter, the detection end of the liquid level sensor penetrates through the cavity to face the interior of the shell, and a liquid outlet is further formed in one side of the bottom of the shell. And an acid discharge pump is arranged on the liquid discharge port. According to the automatic detection device, the working environment is improved, the operation safety and convenience are improved, and meanwhile the requirement for safety management is met.

This invention proposes an indirect steam heating device resistant to strong acid corrosion, belonging to the field of steam heating technology for strong acid corrosion resistance. Addressing the technical problems of existing strong acid environment heating technologies, such as acid concentration dilution, poor corrosion resistance of ordinary materials, low heating efficiency of plastic materials, and small heat exchange area, this invention provides an indirect steam heating device resistant to strong acid corrosion in strong acid environments. It achieves the technical goals of not diluting the acid concentration, long-term resistance to strong acid corrosion, and efficient increase in the temperature of strong acid solutions. Furthermore, by optimizing the pipeline layout to increase the heat exchange area, it further improves heating efficiency, meeting the requirements for efficient oxide layer removal in beryllium copper strip production.

1. The name of this design product: Graphite Acid Remover. 2. Purpose of this product design: used for sample pretreatment, reducing the acid concentration in the sample solution, protecting instruments and equipment, and improving the accuracy of analysis results. 3. The key point of the design of this product lies in its shape. 4. The picture or photo that best illustrates the key points of the design: Design 1 3D drawing. 5. Designate Design 1 as the base design.

The invention discloses a method for inhibiting reduction of the acid concentration of a steam stripping defluorination tower in a wet-process phosphoric acid purification process, which comprises the following steps: 1) after heavy removal and coarse decoloration of phosphoric acid with the concentration of 79% obtained by concentration of concentration equipment, introducing the phosphoric acid into a membrane filter for filtration, and caching the phosphoric acid in a clear liquid aeration tank; 2) monitoring whether the temperature of the phosphoric acid flowing out of the heat exchanger reaches 100-120 DEG C in real time, and if the temperature of the phosphoric acid is lower than 100 DEG C, increasing the flow rate of steam entering the heat exchanger to 1.5-2.2 m < 3 > / h; and 3) defluorinating phosphoric acid in the steam stripping defluorination tower, feeding the defluorinated phosphoric acid into a premixer through a pipeline, mixing the defluorinated phosphoric acid with hydrogen peroxide, and sequentially feeding the mixture into a first decolorizing tower and a second decolorizing tower which are connected in series through a pipeline. After the method is used, phosphoric acid with the mass concentration of 75-77% and the chromaticity of 10-20 black units can be directly obtained without increasing the concentration of phosphoric acid in concentration equipment.

Peroxycarboxylic acid compositions comprising compatible ionic compounds to deliver conductivity signals to enable monitoring of the peroxycarboxylic acid concentration by conductivity when diluted for use are disclosed. Methods of measuring peroxycarboxylic acid concentration by conductivity are also disclosed. Beneficially, conductivity measurement allows a user to determine concentration of the peroxycarboxylic acid at a point of use without cumbersome titration steps to determine the concentration providing various benefits at an application of use.

The present application relates to a kind of acid tank dismantling construction methods in confined space, neutralize acid concentration in acid tank, use purified water to carry out cycle flushing;According to the size of structure platform column spacing, cut several sections segmentedly;Use air pick to remove acid-resistant brick width 300mm in cutting seam, expose tank body rubber lining;Use flat shovel to remove lining in cutting seam;Use oxyacetylene along cutting seam to disintegrate tank body;Remove the pattern plate of structure platform above acid tank, hoist tank body by crane through below platform, rotate 90 degrees, and hoist tank body away from platform edge;Lay down roller steel pipe below, hoist tank body out and place in specified location area and stack.The present application can realize the quick dismantling of acid tank, solve the problem that acid tank is not easy to remove in confined space.The present application can shorten the acid tank dismantling time, and the construction method is reliable in connection;Use crane to disintegrate and hoist to remove, reduce heavy physical labor, improve work efficiency.

The utility model discloses a waste acid concentration treatment and recycling device, which relates to the technical field of treatment and recycling devices and comprises a tank body, a heating structure, a stirring structure, a filtering structure and a placing structure, an electric heating pipe is opened, the electric heating pipe is heated, then the interior of the tank body is heated, a screw is screwed out, then the screw is separated from a first round hole and a second round hole, a first mounting plate is separated from a second mounting plate, and therefore a protection plate is separated from the second mounting plate; the protection plate is separated from the second mounting plate, so that the protection plate can be opened, the electric heating tube can be checked or replaced, and the maintenance cost of the equipment is reduced; when the hot air in the tank body is enough, a third control valve is opened, then waste acid is poured from a liquid inlet pipe, then a motor is started, the motor drives a rotating shaft to rotate, the rotating shaft rotates to drive stirring blades to rotate, and the rotation of the stirring blades is beneficial to driving the hot air in the tank body to flow, so that the evaporation and concentration work of the waste acid is accelerated, and the waste acid is recycled.

The invention discloses a method for extracting scandium from a byproduct FeSO4 # imgabs0 # H2O in a sulfuric acid process titanium dioxide waste acid concentration process, and belongs to the field of valuable resource recovery. The method comprises the following steps: mixing and dissolving FeSO4 # imgabs1 # H2O and water, filtering to obtain a ferrous sulfate solution, freezing, crystallizing and filtering to obtain a scandium-containing solution, and circulating for multiple times to increase the scandium concentration; then ferric iron in the solution is reduced, the pH is adjusted with barium hydroxide, scandium is precipitated, and a mixed solid of barium sulfate and scandium hydroxide is separated out; the method comprises the following steps: dissolving scandium hydroxide with acid, filtering and washing, precipitating scandium with oxalic acid or sodium oxalate, and finally roasting scandium oxalate at high temperature to prepare scandium oxide with Sc2O3 greater than or equal to 99.99% and Sc2O3 / REO greater than or equal to 99.9999%. The method has the advantages of being convenient to operate, simple in technological process, low in production cost and good in environmental protection benefit, industrialization is easy, the scandium element in the sulfuric acid process titanium dioxide waste acid concentration byproduct can be efficiently recycled, and efficient utilization of resources is achieved.

The invention discloses an MTW molecular sieve as well as a preparation method and application thereof. The acid concentration in pores of the MTW molecular sieve accounts for 20-90% of the total acid concentration. According to the invention, the regulation and control of the acid distribution inside and outside the MTW molecular sieve pore can be realized only by regulating and changing the types and the addition amount of the template agent and the alkali metal ions in the raw materials. The molecular sieve with the adjustable number of acid sites in the pore channel shows high activity and adjustable para-position / meta-position product selectivity in an alkylation reaction of olefin / aromatic hydrocarbon.

Stimulation treatments are designed and performed in a manner that takes into account radial acid flow into the formation. A reservoir core plug is selected and a linear core flow test is performed. The core flow test comprises measuring a flowing fraction, injecting into the core plug a treatment volume of at least one candidate stimulation fluid at an injection rate at reservoir conditions, and measuring an effective reaction rate constant. The linear flow data are then scaled to radial flow. A skin, an acid concentration at a wormhole tip and a fluid velocity at a wormhole tip are calculated. A stimulation treatment is then performed. The method can also be performed on analog cores. The stimulation treatment may be matrix acidizing, fracture acidizing or acidizing natural fractures.