213 results about "Mercury adsorption" patented technology

A method for removal of mercury from a gaseous stream containing the mercury, hydrogen and/or CO, and hydrogen sulfide and/or carbonyl sulfide in which a dispersed Cu-containing sorbent is contacted with the gaseous stream at a temperature in the range of about 25° C. to about 300° C. until the mercury concentration in the gaseous stream after contacting the sorbent exceeds a predetermined breakthrough level, signaling a spent sorbent. Arsenic, cadmium and selenium present in the gaseous stream may also be captured along with the mercury. The spent sorbent is then contacted with a desorbing gaseous stream at a temperature equal to or slightly higher than the temperature at which the mercury adsorption is carried out, producing a regenerated sorbent and an exhaust gas comprising released mercury. The released mercury in the exhaust gas is then captured using a high-capacity sorbent, such as sulfur-impregnated activated carbon, at a temperature less than about 100° C. The regenerated sorbent may then be used to capture additional mercury from the mercury-containing gaseous stream. The process may be carried out at pressures in the range of about 1 bar to about 200 bar.

To provide mercury-removal adsorbents, a method of producing mercury-removal adsorbents, and a method of removing mercury by adsorption which are capable of realizing efficient removal of mercury by adsorption from liquid hydrocarbon, thermal power station exhaust combustion gas, natural gas, off gas of various process plants, and so on which contain mercuries in various forms such as elemental mercury, ionic mercury, and organic mercury, and a concomitant hindering mercury adsorption.

Mercury-removal adsorbents carrie potassium iodide in an amount of 27 to 70% of a total adsorbent weight, and a volume of pores with a 1 μm pore diameter or more in the mercury-removal adsorbents is 0.6 mL/g or more. These mercury-removal adsorbents are filled in, for example, an adsorption tower 10, and a hydrocarbon liquid is passed therethrough (mercury removal step). In a case where the hydrocarbon liquid contains saturated water, a dehydration unit 9 or the like is installed on a preceding stage of the adsorption tower 10 to dehydrate the hydrocarbon liquid (dehydration step).

Belonging to the technical field of wastewater treatment, the invention in particular relates to a modified vermiculite mercury removal adsorbent, a preparation method and application thereof. The method includes: taking vermiculite as the main raw material, soaking vermiculite with thickness of 0.6-1mm and a particle size of 7-8mm with 25% hydrogen peroxide, performing heating, then placing the vermiculite in certain power microwave to perform heating, thus obtaining expanded vermiculite, grinding the expanded vermiculite to less than 100 meshes, then conducting further modification with a certain amount of chitosan to obtain the modified vermiculite adsorbent with a chitosan loading capacity of 0.01g/g-0.05g/g, and applying the adsorbent for treatment of mercury-containing wastewater. The modified vermiculite mercury removal adsorbent prepared by the method provided by the invention has the advantages of low price, simple operation and the like, and mercury removal examples prove that the adsorbent has fast adsorption speed and strong adsorption capacity to mercury ions, and can be used for treatment of mercury-containing wastewater with a wide concentration range.

The present invention relates to a mercury-containing wastewater treatment technology field, in particular to an attapulgite-crosslinked chitosan composite adsorbent and its solid-phase synthetic method. The attapulgite-crosslinked chitosan composite mercury adsorbent in the invention is synthesized by the method of adding chitosan and glutaraldehyde in batches. In consideration of the limited solubility of chitosan, batch addition can not only dissolve chitosan, but also minimize the use of organic acid, resulting in less discharge of wastewater and waste gas, which is suitable for large-scale industrial production. The prepared mercury adsorbent can be applied to the removal of mercury ions in the wastewater owing to the excellent adsorptive property and regeneration performance. Meanwhile, the solid-phase synthetic procedure for preparing the mercury adsorbent is simple, easy to handle and environmental-friendly. Moreover, the product cost is greatly reduced due to the use of attapulgite.

The invention relates to a method for preparing rare-earth element doped composite metal oxide mercury removal catalyst in the technical field of chemical engineering and environmental protection. The method prepares a mercury removal catalyst by rare-earth element doped composite metal oxide to realize double functions of zero-valent mercury adsorption trapping and catalytic oxidation, which not only can be sprayed into smoke gas in a powder mode to trap the zero-valent mercury onto the mercury removal material, but also can be embedded with smoke gas in a static bed mode to cooperate with oxidant to catalytically oxidize the zero-valent mercury into divalent mercury, and can be absorbed by downstream desulfurization equipment. The mercury removal material prepared by the method has better adsorption capability, catalytic function and sulfur resistance on the zero-valent mercury, and has simple application process, convenient operation and maintenance.

The invention discloses a preparation method of special modified active carbon for removing mercury. The method comprises the following steps of: washing wooden particle active carbon through hydrochloric acid and distilled water, and then drying the washed wooden particle active carbon to standby; heating the active carbon and the hydrogen peroxide with the concentration being 25 to 30wt% at the temperature of 50 to 70 DEG C for 2 to 4h according to the mass-to-volume ratio of 6g:(15-10)ml, and then carrying out the ultrasonic treatment on the active carbon for 20 to 40min; and standing, filtering, drying, washing and drying the active carbon to obtain the special modified active carbon for removing the mercury. The special modified active carbon has high mercury removal efficiency, and the maximal mercury adsorption volume can reach 5.3mg/g and is 1.5 times that of unmodified active carbon.

The invention discloses a modified biomass activated coke mercury removal adsorbent and a preparation method thereof. The mercury removal adsorbent is biomass activated coke undergoing phosphoric acid activation and halogenated ammonium salt modification dual treatment. The preparation method includes: immersing biomass particles into a phosphoric acid solution to conduct continuous stirring impregnation, performing filtering and drying, then under an N2 atmosphere, carrying out pyrolysis activation on the biomass particles subjected to phosphoric acid impregnation treatment; then conducting washing till the filtrate has a pH value of 6-7, and performing drying under 45-50DEG C; immersing the biomass activated coke into a halogenated ammonium salt solution, and carrying out continuous stirring impregnation for 1-2h; and conducting filtering and drying so as to obtain the modified biomass activated coke mercury removal adsorbent, which has the advantages of convenience and simplicity, less pollution, easy industrial popularization and the like.

The invention relates to a mercury-containing fumes emission continuous monitoring system and a monitoring method thereof. The monitoring system comprises a sampling device, a reactor, a gas and water separating device, and a mercury concentration measuring device which are sequentially connected through a pipeline; the reactor is connected with a first container containing a divalent mercury adsorption solution through a first peristaltic pump, and is also connected with a second container containing a divalent mercury reduction solution through a second peristaltic pump; and the sampling device, the first peristaltic pump, the second peristaltic pump and the mercury measuring device are separately electrically connected with a control circuit. The monitoring method comprises: firstly, the divalent mercury adsorption solution is pumped into the reactor to adsorb the divalent mercury in the fumes, and the mercury concentration measuring device is used to measure the concentration of zero valent mercury in the fumes; secondly, the divalent mercury reduction solution is pumped into the reactor to reduce the divalent mercury to be zero valent mercury, and the concentration obtained by the mercury measuring device at the same time is the concentration of the mercury in the fumes. The monitoring system of the invention is simple in structure, can prevent environment pollution, is highly reliable, achieves on-line automatic continuous monitoring, and improves operation efficiency and measurement accuracy.

The invention relates to a zinc sulfide base mercury adsorbent for flue gas zero-valent mercury capturing and a preparation method of the zinc sulfide based mercury adsorbent. The adsorbent is a cobalt-doped zinc sulfide mercury adsorption material CoxZn1-xS, in the formula, x represents the stoichiometric ratio of cobalt in a solution, and the stoichiometric ratio is 0.1-0.3. The preparation method comprises the following steps: (1) dissolving a cobalt salt and a zinc salt of a certain mole ratio into deionized water so as to obtain a mixed solution; (2) mixing and stirring the mixed solutionwith a precipitant; (3) putting a suspension liquid into a reactor, and carrying out heating treatment on the reactor in a baking oven; (4) repeatedly washing the obtained precipitate with deionizedwater, and drying, thereby obtaining the zinc sulfide based mercury adsorbent. Compared with the prior art, the preparation method is wide in raw material source, simple and controllable in preparation process and gentle in reaction condition, and the prepared adsorbent has a mercury adsorption capability which is improved by dozens of times when being compared with pure zinc sulfide, in additionhas a very good anti-SO2 influence property, is capable of maintaining certain high activity within a long time, and is particularly applicable to adsorption and removal of zero-valent mercury in a metallurgical flue gas.

The invention provides a demercuration and regeneration method for a copper-based demercuration adsorbent. The demercuration and regeneration method for the copper-based demercuration adsorbent includes the following steps that the used copper-based demercuration adsorbent and a catalyst are mixed and preheated, then mixed gas containing oxygen, hydrogen chloride and shielding gas is introduced, a demercuration reaction is carried out, and a solid mixture and desorbed mercury are obtained; the solid mixture is screened and ultrasonically washed, and a crude regenerated copper-based demercuration adsorbent is obtained; the crude copper-based demercuration adsorbent is dried and calcined, and the regenerated copper-based demercuration adsorbent is obtained. The catalyst contains chloride and silicon dioxide, or the catalyst contains sulfide and silicon dioxide. Based on the mass of the mixed gas being 100%, the mass ratio of hydrogen chloride to oxygen to the shielding gas is (5%-10%):(1%-2%):(88%-94%); the ultrasonic washing frequency ranges from 1 MHz to 1.5 MHz.

The invention discloses a normal-temperature and normal-pressure preparation method and application of a metal selenide mercury adsorbent. The metal selenide mercury adsorbent is prepared at normal temperature and normal pressure by adopting a precipitation method. The metal selenide mercury adsorbent comprises a compound formed by selenium and one or more of chromium, manganese, iron, copper, cobalt, nickel, zinc, molybdenum, silver and cadmium and a composite of the compound, unstable mercury is converted into stable mercury selenide, mercury in industrial tail gas or by-products of fire coal, metallurgy, waste incineration, cement production and the like is removed, mercury enriched in mercury-containing articles for daily use is absorbed, the recovery and reutilization of mercury resources are realized, and mercury to be treated can exist in the forms of a simple substance state, a free state and/or a compound state and the like. As the metal selenide has extremely high mercury adsorption capacity and adsorption rate, realization of large-scale preparation of the metal selenide under normal temperature and pressure conditions has great significance on mercury pollution prevention and control, and the corresponding technology has wide market application prospects.

Disclosed is a novel demercuration catalyst. As mercury has extremely high accumulation performance in the environment and in organisms, it has very strong toxicity for mankind and wild animals and plants even the concentration is very low. In recent years, mercury is considered as another pollution problem in the world. Present existing demercuration catalysts have disadvantages of poor anti-poisoning capability and high cost, and are difficult to realize industrialization. In order overcome these advantages, a novel demercuration catalyst is invented. The product is prepared from TOx (T is Cu, Fe and V) and ROy (R is La and Ce) with the addition of titanium dioxide pillared montmorillonite. The invention belongs to the technical field of separation. The demercuration catalyst can be used for elemental mercury removal from flue gas. The invention is characterized in that the catalyst has high mercury adsorption capability and mercury oxidation catalysis capability. The catalyst has very strong anti-poisoning capability.

The present invention provides a straw-based selective mercury removal material preparation method, which comprises: (1) carrying out a steam explosion treatment on straws, and then treating at a temperature of 400-800 DEG C under vacuumizing and nitrogen atmosphere; (2) placing the product obtained in the step (1) into a reductive sulfur group-containing mixing liquid, carrying out stirring mixing, filtering, and drying, wherein the reductive sulfur group-containing mixing liquid is a mixing liquid of ammonium thiocyanate, ammonium thiosulfate and thioglycolic acid; and (3) mixing the product obtained in the step (2) and sublimed sulfur, heating under vacuumizing and nitrogen introducing conditions to achieve a temperature of 450 DEG C, maintaining for 2 h, carrying out program heating to 600-1000 DEG C, maintaining the vacuumizing and nitrogen introducing for 2 h, cooling, and grinding so as to obtain the straw-based selective mercury removal material. The invention further provides the mercury removal material prepared through the method and applications of the mercury removal material in mercury removal. According to the present invention, the straw-based selective mercury removal material has advantages of high mercury adsorption capacity, high mercury removal rate, rapid mercury removal, high selectivity, cheap and easily available raw materials, simple and feasible preparation process, environmental protection, economy, and good application prospect.

The invention discloses a preparation method of a gaseous mercury adsorbent. The preparation method comprises following steps: (1) mixing active carbon and concentrated sulfuric acid, aging, filtering, and washing to obtain modified active carbon; (2) mixing thiourea and metal salts to obtain a metal thiourea mixed solution, wherein the metal ions of the metal thiourea mixed solution are copper ions and/or iron ions; and (3) mixing modified active carbon and the metal thiourea mixed solution to impregnate modified active carbon, and after impregnation, drying obtained materials in vacuum to obtain the gaseous mercury adsorbent. The invention also discloses an application of the gaseous mercury adsorbent on absorbing gaseous mercury in high sulfur smelting exhaust gas. The prepared gaseous mercury adsorbent can absorb gaseous mercury and divalent mercury in flue gas, has an excellent sulfur-resistant performance, and has high mercury removing efficiency, even if the concentration of sulfur dioxide is high.

The invention discloses a macroporous skeleton hydrophobicmercury removal material, a preparation method and application thereof. A simple one-step precipitation method is adopted, a surfactant is used for regulating and controlling the crystal size of metal sulfide, the metal sulfide is fixed on a macroporous skeleton hydrophobic material, and a novel mercury removal material is obtained. The preparation method of the macroporous skeleton hydrophobic mercury removal material is simple, the contact area of metal sulfide minerals and mercury is increased, and the resistance of an adsorbent to flue gas is reduced. The macroporous framework hydrophobic mercury removal material has extremely high mercury adsorption capacity and adsorption rate, the hydrophobic performance of pure metal sulfide is improved, and the obtained mercury removal material can be used as a mercury removal medium to be applied to a fixed bed or a liquid phase (such as a wet dust removal device) to be in contact with gaseous elemental mercury; and volatile gaseous elemental mercury is converted into stable solid mercuric sulfide, and the material has the advantages of being flexible in application, high in efficiency, environmentally friendly and the like.

The invention relates to a system for simultaneously sampling and detecting flue gas NO and mercury. The method comprises an off-line mercury detection apparatus and a sampling probe gun used for stretching into a flue, a flue gas pipeline of the sampling probe gun is several independently arranged quartz pipelines, an outlet of the quartz pipeline is communicated to a flue gas dedusting, acid-removal and dehumidifying apparatus, a flow control apparatus and a NO detector, the flow control apparatus and the NO detector are connected to a computer; a heating layer used for keeping the sampling probe gun at temperature of more than 120 DEG C is arranged on an inner wall of a housing of the sampling probe gun, an active carbon adsorption pipe is arranged on each quartz pipeline, and the active carbon adsorption pipe is filled by an adsorbent, the adsorbent is divided into the adsorbent which is a mercuric oxide capture layer of KCl and a simple substance mercury adsorption layer of mercury-removal active carbon according to a flue gas passing sequence. The system can simultaneously realize sampling and detection of NO and mercury pollutants at a same sampling point in the flue gas, and can realize flow parallel sampling and constant current sampling, the detection results can be mutually calibrated.

The invention provides a preparation method of a mercury removal adsorbent for Indonesian oil sand tailings. The method includes: taking Indonesian oil sand tailings as raw materials, subjecting to high-temperature firing and digestion in water to obtain the mercury removal adsorbent for the Indonesian oil sand tailings. The mercury removal adsorbent has a certain mercury removal rate, the mercury removal rate is greatly increased after addition of a strong oxidant in a preparation process, and when the mass percent of the added strong oxidant reaches 1%, the mercury removal rate of the obtained mercury removal adsorbent reaches 95% or above. The preparation method of the mercury removal adsorbent for the Indonesian oil sand tailings is simple, free of secondary pollution in a manufacturing process and high in mercury adsorption rate, recycling of the oil sand tailings is realized, the problem of treatment of oil sand tailings which are hazardous solid wastes is solved, and remarkable economic benefits and environmental protection benefits are achieved.

The invention discloses a method for preparing vinyl chloride synthesizing catalysts from mercury in waste gas. The method includes impregnating activated carbon by the aid of metal chloride solution MCl<x> and then adsorbing the null-valence mercury in the flue gas to prepare the vinyl chloride synthesizing catalysts. The vinyl chloride synthesizing catalysts can be applied to industrially catalytically synthesizing vinyl chloride. Compared with the prior art, the method has the advantages that the method is easy to implement, low in cost and high in mercury adsorption capacity and absorption quantity, the proportion of the null-valence mercury, which is transformed into bi-valence mercury, in the coal-fired flue gas can be increased, the purpose of removing the mercury in the flue gas can be achieved, the novel catalysts obtained after adsorption reaction is carried out can be applied to industrially catalytically synthesizing the vinyl chloride and are stable in catalytic performance and long in usage time, and the like.

The invention relates to a device and a method for removing mercury from a boiler flue gas of a power station, and belongs to the field of air pollutant control. The device disclosed by the invention comprises a dust removal system, an adsorbent injection system, an adsorbent delivery system and an adsorbent regeneration system, wherein an adsorbent injection orifice is formed between an electrostatic dust collector and a bag-type dust remover; the electrostatic dust collector takes charge of collecting coarse ashes and most of fine ashes; and the bag-type dust remover only collects the adsorbent and a few of fine granular fly ashes, and thus the quality of the fly ashes is not affected, and meanwhile, efficient dust collection is achieved. A certain ratio of fine ashes and adsorbent in a fine ash bucket are conveyed to a regeneration device to heat and regenerate in a cycle by using the mercury adsorption property of the fly ashes, and thus cyclic utilization of the adsorbent is achieved; the mercury removal efficiency is increased, and the mercury removal operation cost is obviously lowered.