Abstract:
The present disclosure provides a graded oxygen regulating, explosion preventing and recycling system and method for liquid nitrogen wash tail gas, and relates to the technical field of environmental protection and energy utilization. The system provided by the present disclosure includes a multi section catalytic combustor, the multi-section catalytic combustor being divided into a first-section catalytic combustion region, a second-section catalytic combustion region, and a third-section catalytic combustion region, the first-section catalytic combustion region and the second-section catalytic combustion region being internally filled with multiple layers of catalysts that are disposed at intervals, and an air flow guide pipe being arranged above each layer of catalyst; a first-section heat exchanger communicating with the first-section catalytic combustion region; a second-section heat exchanger communicating with the second-section catalytic combustion region; a pulverized coal drying section communicating with the second-section heat exchanger; and a boiler section communicating with the third-section catalytic combustion region.
Abstract:
A method for treating arsenic-containing flue gas is disclosed. In the method, the arsenic-containing flue gas is subjected to a dry pre-dedusting treatment, and the dedusted flue gas is pre-cooled and then introduced into a vortex quenching system. The arsenic-containing flue gas is divided into high-temperature flue gas and low-temperature flue gas through the vortex quenching system. The outlet temperature of the low-temperature flue gas is dropped below the desublimation temperature of gaseous arsenic trioxide. The low-temperature flue gas is subjected to a gas-solid separation to obtain solid arsenic trioxide and treated flue gas.
Abstract:
The invention discloses a method for simultaneously removing SO2 and NOx in flue gas: uniformly mixing a water-soluble ruthenium salt with ammonia water to obtain an aqueous solution of a ruthenium-amine complex; subjecting the flue gas and the aqueous solution of the ruthenium-amine complex to a countercurrent contact reaction under the temperature of 5-60° C., pH of 7.5-12 to obtain a solution A and purified gas; discharging the solution A of the step (2) into a crystallization tank to crystallize and separate an ammonium salt to obtain a solution B, returning the solution B to replace the aqueous solution of the ruthenium-amine complex. The invention utilizes the ruthenium-amine complex having a strong capability of complexing with NO as well as residual oxygen in the flue gas to carry out liquid phase catalytic oxidation to convert the NOx into ammonium nitrate, and the removal efficiency of the NOx and the SO2 is high.
Abstract:
The present invention discloses a method of preparing a catalyst for low-temperature synergistic catalytic purification of NOx and HCN in a flue gas, and the use thereof. Citric acid is dissolved in ethanol to obtain a citric acid/ethanol solution; tetrabutyl titanate is added, mixed uniformly to obtain a tetrabutyl titanate-citric acid/ethanol solution; glacial acetic acid is added dropwise to react for 30-40 min to obtain a solution A; the metal salt solution was added dropwise into the solution A, mixed uniformly and added with nitric acid, ammonium hydroxide is added dropwise to adjust the pH value, and the temperature is raised at a constant speed to obtain a gel B; dried and then then baked at a temperature of 300-500° C. for 3-4 h, cooled in the furnace, pulverized, tableted and sieved to obtain the catalyst for the low-temperature synergistic catalytic purification of NOx and HCN in the flue gas.
Abstract:
A method for production of ammonium phosphate from phosphate rock slurry. The method includes: introducing flue gas containing SO2 into a phosphate rock slurry, to yield an absorption solution; evaporating waste ammonia water containing 10-20 wt. % ammonia to yield ammonia gas; introducing the ammonia gas into the absorption solution at a temperature of 110-135° C. until a neutralization degree of the absorption solution reaches 1.5-1.6, thus yielding an ammonium phosphate solution and calcium sulfate; separating the calcium sulfate from the ammonium phosphate solution; and introducing the ammonium phosphate solution to a granulator for granulation to yield ammonium phosphate granules; drying and sieving the ammonium phosphate granules, thereby yielding ammonium phosphate.
Abstract:
The present invention discloses a method for detoxifying chromium slag by using high sulfur coal. The method includes: sieving chromium slag into coarse-grained chromium slag and fine-grained chromium slag, air-drying and crushing both the coarse-grained chromium slag and the fine-grained chromium slag; separately mixing the crushed coarse-grained chromium slag and fine-grained chromium slag with the crushed high sulfur coal uniformly; adjusting pH values of a coarse-grained slag mixture and a fine-grained slag mixture to 8.0-11.0 and moisture content thereof to 12%-18%; conducting reduction on the treated coarse-grained slag mixture and fine-grained slag mixture, where the reduction temperature of the fine-grained slag mixture is 500-700° C., the reduction time of the fine-grained slag mixture is 10-30 min, the reduction temperature of the coarse-grained slag mixture is 800-1000° C., the reduction time of the coarse-grained slag mixture is 10-30 min; after the reduction, conducting water quenching, and discharging the product.
Abstract:
The invention is a device and method for purifying sulfur dioxide and nitrogen oxide in flue gas with an electrolysis-chemical advanced oxidation enhanced ammonia method. The device includes a thermal activation reactor, ammonium hydroxide storage tank, absorption tower, electrolytic bath and crystallization separator. The method takes raw material part of an ammonium sulfate solution that is a reaction product of ammonia and sulfur oxide in flue gas, and an ammonium persulfate solution prepared by electrolysis of an electrolytic bath as an oxidant to enhance the efficiency of purifying sulfur dioxide and nitrogen oxide in the flue gas with an ammonia method. A thermal activation reactor activates an ammonium persulfate containing solution to generate a strong oxidizing SO4.−, so that NOx and SO2 in the flue gas may be more efficiently converted into a product having higher solubleness for enhanced removal of sulfur dioxide and nitrogen oxide in the flue gas.
Abstract:
A method for treating arsenic-containing flue gas is disclosed. In the method, the arsenic-containing flue gas is subjected to a dry pre-dedusting treatment, and the dedusted flue gas is pre-cooled and then introduced into a vortex quenching system. The arsenic-containing flue gas is divided into high-temperature flue gas and low-temperature flue gas through the vortex quenching system. The outlet temperature of the low-temperature flue gas is dropped below the desublimation temperature of gaseous arsenic trioxide. The low-temperature flue gas is subjected to a gas-solid separation to obtain solid arsenic trioxide and treated flue gas.
Abstract:
The present invention discloses a method for ammonium-enhanced flue gas desulfurization (FGD) by using red mud slurry. The method specifically includes: crushing red mud, sieving the crushed red mud, slurrying the red mud, conducting aeration treatment, adding an ammonium salt and/or ammonia, and conducting natural sedimentation to obtain pretreated red mud slurry and pretreated red mud liquor; adding an ammonium salt and/or ammonia to the slurry, adding water and conducting uniform mixing, conducting pre-FGD, conducting deep desulfurization on treated flue gas by using the pretreated red mud liquor, and directly discharging desulfurized flue gas; and charging the pretreated red mud slurry and the pretreated red mud liquor obtained after the treatment to a replacement tank below, adding lime milk to the replacement tank, conducting stirring and natural sedimentation, conducting soilization on subnatant thick red mud slurry, and refluxing the supernatant to a red mud aeration tank.
Abstract:
Disclosed is a process for purifying tail gases from an ore-smelting electrical furnace by catalytic oxidization, which comprises: impregnating a catalyst carrier in an impregnating solution, then aging, calcinating, and finally drying, so as to prepare a catalyst of high efficiency; then washing the tail gases from an ore-smelting electrical furnace with an aqueous alkali-containing solution, pre-heating the alkali-washed tail gas; and adjusting the oxygen volume content in the tail gases, charging the tail gases at a certain speed, purifying the gases by a catalytic oxidization fixed bed containing the catalyst of high efficiency, cooling the purified gas, so as to obtain the feed gases for C1 chemistry.