2291 results about "Nitrogen oxides" patented technology

The invention relates to the technical field of industrial flue gas purification, and discloses a flue gas denitration pollution reduction and carbon reduction method and system based on model prediction control. The method comprises the following steps: collecting flue gas data through a sensor to obtain a flue gas distribution state; the state is processed through a preset model, and a nitrogen oxide concentration predicted value is determined; judging a regulation and control demand based on the predicted value and generating an adjustment coefficient sequence; calculating an opening value of an ammonia spraying distributor by adopting a particle swarm optimization algorithm, and determining ammonia spraying amount distribution; a control instruction is sent according to ammonia spraying amount distribution, and a temperature uniformity index is evaluated based on temperature feedback data; adjusting optimization algorithm parameters according to the indexes, and generating an optimized ammonia spraying strategy; updating the predicted value and determining the stable range of the denitration efficiency; verifying the ammonia escape concentration in the stable range to obtain a system performance index; and forming a continuous regulation and control sequence according to cyclic feedback of the indexes. According to the invention, accurate dynamic regulation and control of ammonia spraying amount are realized, denitration efficiency and system stability are effectively improved, and the risk of ammonia escape is significantly reduced.

The invention relates to a boiler combustion optimization control system of a thermal power plant, relates to the technical field of thermal power generation control, and aims to solve the problems of inaccurate multi-source data perception, slow control response and insufficient multi-target collaborative optimization capability under fire coal quality fluctuation and load change. The system comprises a data perception and fusion module, a working condition self-adaptive identification module, a multi-target dynamic optimization decision module and a distributed execution control module, and through multi-source data acquisition and feature extraction, depth time sequence mode identification, multi-target optimization model solving and distributed coordination control, the multi-target dynamic optimization decision module and the distributed execution control module are subjected to multi-source data fusion. Dynamic balance of boiler heat efficiency improvement and nitrogen oxide emission reduction is achieved, and adaptability and control precision of the system under complex working conditions are enhanced.

The invention provides a nitrogen oxide incineration equipment control method for drying carbonization, which comprises the following steps: acquiring combustion characteristic data of high-humidity sludge blocks in a fluidized bed incinerator, and extracting nitrogen oxide peak intensity, occurrence time, duration and peak shape steep degree to obtain a parameter set; real-time load data of the induced draft fan are obtained, the hearth negative pressure stability fluctuation range is analyzed in combination with the adjustment value, and if fluctuation exceeds a preset safety range, the load adjustment amplitude of the induced draft fan is calculated, and a load adjustment curve is generated; a multi-actuator cooperative control time sequence model is constructed based on the load adjustment curve and the adjustment value, the nitrogen oxide peak generation time and the duration are fused, the cooperative adjustment time sequence of secondary air supply and the draught fan load is calculated, and a control instruction is generated; and a control instruction is transmitted to a fluidized bed incinerator executing mechanism, the opening state of the tuyere and the air volume ratio are adjusted, the load of the induced draft fan is updated, and the adjusted hearth operation parameters are continuously monitored.

The invention discloses a denitration system inlet nitric oxide disturbance and super-emission control method and system, and the method comprises the steps: adjusting the operation oxygen amount and the over fire air ratio in real time based on the measured values of the carbon monoxide concentration and the nitric oxide concentration of the denitration system inlet; based on denitration system operation data, combining actual sampling delay time to carry out sample data alignment and construct a training sample set; constructing a prediction model based on the training sample set, obtaining a nitrogen oxide concentration prediction value of the inlet of the denitration system through the prediction model, and updating the prediction model in real time; based on the difference between the average value of the outlet nitrogen oxide concentration of each partition and a set value and the difference between the concentration value of the nitrogen oxide at the outlet of the denitration system and the set value, and by combining the predicted value of the nitrogen oxide concentration at the inlet of the denitration system, treatment measures after the nitrogen oxide concentration super-emission are set in a segmented mode. The control performance of the denitration system can be improved, the ammonia spraying amount is reduced, the ammonia escape concentration is reduced, and the system automation input rate is increased.

The invention relates to an SSZ-39 molecular sieve and preparation and application thereof.The preparation method comprises the following steps that 1, after water, an alkali source and a template agent are mixed, mesoporous Y zeolite and a silicon source are added, the mixture is stirred to be uniform, and the mixture is aged to be in a white gel shape; (2) transferring the obtained white gel into a reaction kettle, carrying out crystallization treatment, and filtering, washing, drying and calcining a crystallized product to obtain a Na-SSZ-39 molecular sieve; (3) carrying out ammonium ion exchange on the Na-SSZ-39 molecular sieve, filtering, washing, drying and calcining to obtain an H-SSZ-39 molecular sieve; and (4) carrying out copper ion exchange on the H-SSZ-39 molecular sieve, filtering, washing, drying and calcining to obtain the Cu-SSZ-39 catalyst. Aluminum used in the method is provided by mesoporous Y zeolite, the pure-phase SSZ-39 molecular sieve can be synthesized in a wide gel range, the crystallization time is shortened to 24 h, and after copper ion exchange, the pure-phase SSZ-39 molecular sieve shows high denitration activity in the selective catalytic reduction reaction of nitrogen oxide ammonia.

The invention provides a method for rapidly detecting the content of nitrogen oxides in air. The method comprises the following steps: acquiring original signal data of nitrogen oxides in air in a target detection area in real time through a plurality of nitrogen oxide sensors; performing noise reduction filtering processing on the original signal data to generate target signal data; performing signal drift compensation correction on the target signal data based on a preset sensor calibration model to generate standardized concentration data; performing space-time correlation analysis on the standardized concentration data through a nitrogen oxide concentration prediction algorithm model in combination with environment parameter data collected in real time to generate a target prediction concentration value; and comparing the target predicted concentration value with a preset concentration standard threshold value based on a fuzzy logic judgment algorithm, and constructing a detection report. The whole process from data acquisition to report generation is intelligent, and the detection flexibility is remarkably improved.

The invention discloses an efficient pulsating heat pipe air pre-heater gas stove, and relates to the technical field of gas stoves. The air pre-heater comprises an air pre-heater body, a pulsating heat pipe and an air supply pipeline, the pulsating heat pipe is embedded in an inner cavity of the air pre-heater body, and the bottom of the air pre-heater body communicates with the top of the air supply pipeline; the air pre-heater body comprises a heat insulation radiation cavity and an air pre-heating cavity. The heat transfer efficiency of the pulsating heat pipe is far higher than that of traditional metal heat conduction, heat of high-temperature flue gas can be rapidly absorbed, waste heat loss is reduced, the heat efficiency is improved, secondary air is heated through the air preheater, the temperature of the secondary air is increased, the combustion temperature is increased, gas combustion is more sufficient, emission of carbon monoxide and nitric oxide is reduced, and the energy-saving and environment-friendly effects are achieved. The pulsating heat pipe has the unique advantages of being small and exquisite in structure, flexible in arrangement and efficient in heat transfer, and the heat efficiency of the gas stove is effectively improved through the L-shaped pulsating heat pipe heat insulation air pre-heater structure.

The invention relates to the technical field of flue gas purification, in particular to a nitrogen oxide and dioxin efficient synergistic removal and discharge system which comprises a pretreatment frame and an advanced treatment frame, the pretreatment frame is arranged at the upper end of the advanced treatment frame, and a removal mechanism, a transition air cylinder and an activated carbon storage cylinder are sequentially arranged in the pretreatment frame; local parts of the bottoms of the transition air cylinder and the activated carbon storage cylinder extend into the advanced treatment frame, and a reaction cylinder II is arranged in the advanced treatment frame and corresponds to the activated carbon storage cylinder up and down; the efficient synergistic removal of nitrogen oxides and dioxin is realized through the synergistic treatment of a two-stage layered structure, dynamic mixing deacidification and dynamic adsorption optimization, and meanwhile, the adaptability of equipment to complex working conditions is improved through an adjustable transmission assembly.

The invention relates to the technical field of hydrogen internal combustion engines, in particular to a water-hydrogen combined supply internal combustion engine which comprises a first power generation unit driven by hydrogen and air combusted by a hydrogen internal combustion engine unit. The gas recovery unit converts water vapor in exhausted gas into liquid water through a condensation driving module and drives the second power generation unit at the same time; the fuel supply unit adjusts the hydrogen injection amount through a generated adjusting instruction based on multi-dimensional data detected by the monitoring unit and processed by the data processing unit and the confidence decision-making unit, and then generation of nitric oxide is inhibited. Condensate water recovery and combustion control of the hydrogen internal combustion engine are deeply combined, the actual exhaust humidity is reversely deduced by monitoring the flow of the condensate water, the gas detection error tolerance range is dynamically corrected, the hydrogen-oxygen combustion ratio judgment result is linked, safety amplitude limiting control over hydrogen fuel supply is achieved, and nitrogen oxide generation of the hydrogen internal combustion engine is reduced.

The invention discloses a method for predicting nitrogen oxide infection change of a plant based on an AI image in the technical field of plant research, and the method comprises the steps: building a dynamic mapping relation of morphological indexes-infection concentration and time; the image morphology of the plant under time lapse and / or other concentrations is directly predicted by inputting the current image of the plant, the plant tissue does not need to be damaged, the whole-stage dynamic monitoring of the same plant from the health state to the pollution stress can be realized through regular image acquisition, the interference of traditional chemical sampling on the plant growth is avoided, and the monitoring accuracy is improved. The method is particularly suitable for rare plant or long-term ecological research, the abstract RGB value and the nitrogen oxide concentration are converted into visual results such as a color gradient diagram and a dynamic feature point evolution curve, non-professionals can rapidly judge the pollution level through color depth and patch distribution, and the environment early warning response time is shortened.

The invention relates to the technical field of flue gas denitration, and discloses an efficient dust and nitrate integrated SCR denitration system and method in a high-temperature and low-dust environment. A lower high-temperature dust removal unit containing a gradient three-dimensional porous metal fiber filtering element and an upper SCR denitration reactor located at the downstream of the lower high-temperature dust removal unit containing a multi-layer vanadium-titanium honeycomb type catalyst module are arranged in the upper SCR denitration reactor; the ammonia spraying module sprays ammonia to the upstream or the interior of the SCR reactor; and the intelligent control module controls the ammonia spraying and dust removal unit to remove dust, comprises a catalyst characteristic identification sub-module, a working condition disturbance prediction sub-module and a collaborative optimization control sub-module, and realizes an optimization decision of a final ammonia spraying instruction. High-temperature dust removal and SCR denitration are integrated in the integrated box body, so that the compactness of the system structure is realized; front efficient dust removal provides a clean flue gas environment for the catalyst, the service life of the catalyst is effectively prolonged, and the denitration efficiency is guaranteed; and the intelligent control module ensures the accuracy and self-adaption of ammonia spraying operation, and the removal rate of nitrogen oxides and the operation economy are remarkably improved.

The utility model discloses a lepidolite spodumene roasting flue gas multi-pollutant efficient treatment device which comprises a high-temperature dust removal and denitration integrated tower, a fan, a flue gas deacidification tower and a flue gas heat exchanger, the high-temperature dust removal and denitration integrated tower is communicated with a kiln tail of a roasting kiln, and a cooling section of the flue gas heat exchanger is communicated with the high-temperature dust removal and denitration integrated tower and the fan. Flue gas is subjected to heat exchange in the cooling section and then conveyed to the flue gas deacidification tower through a fan, a gas outlet of the flue gas deacidification tower is communicated with the heating section of the flue gas heat exchanger, the flue gas is subjected to heat exchange with flue gas of the high-temperature dust removal and denitration integrated tower in the flue gas heat exchanger to be heated, and the flue gas is discharged through a chimney communicated with the heating section on the flue gas heat exchanger. The device disclosed by the utility model can be used for cooperatively treating various pollutants including dust, SO2, HF, HCL, nitrogen oxides, dioxin, heavy metals and the like, so that high-efficiency treatment on flue gas is realized, and good economic benefits are achieved.

The invention relates to the technical field of bypass ventilation denitration systems, and discloses an intelligent bypass ventilation SCR (Selective Catalytic Reduction) coupling SNCR (Selective Non-Catalytic Reduction) denitration system which comprises a smoke chamber, a cyclone cylinder, a precise ammonia spraying system, an air mixing chamber, a cooling fan, a cold air valve, a dust collection chamber, an SCR reactor, an exhaust fan, a chimney, a stock bin, a bin pump, a compressed air system and an intelligent control system, the air inlet is connected with the smoke chamber, and the feed opening is connected with the bin pump. Under any working condition, NOx emission at a chimney outlet can reach the standard, the ammonia water consumption is lowest, the denitration effect is good, the investment cost is low, the problem that NOx emission of the kiln tail chimney is unstable and prone to exceeding the standard is solved, the catalyst abrasion and blocking risk can be greatly reduced, the catalyst dosage is small, the maintenance cost is low, and the method is suitable for industrial production. And long-term stable operation of the system is realized.

The invention discloses a fire grate, a combustor and a water heater, and relates to the technical field of water heaters, the fire grate comprises a fire grate body and a combustion head, the fire grate body is provided with a mixing cavity and at least two air inlet flow channels, the mixing cavity is provided with a fire opening, the exhaust ends of the at least two air inlet flow channels are communicated with the mixing cavity, and the combustion head is communicated with the mixing cavity. The gas inlet end of each gas inlet flow channel forms an injection opening, each injection opening is used for conveying gas and air to the corresponding gas inlet flow channel, the combustion head is arranged on the fire opening, and the combustion head is provided with a plurality of fire holes communicated with the mixing cavity. According to the technical scheme provided by the invention, the primary air coefficient of the fire grate can be increased, the overall high temperature of the combustion head is prevented, and the flame distribution of the combustion head is more uniform, so that the local high temperature of the combustion head is avoided, the generation of thermal nitrogen oxides can be greatly reduced, and the emission of harmful substances is reduced.

The invention relates to the technical field of industrial measurement, and provides an industrial process soft measurement method and device, a storage medium and computer equipment, and the method comprises the steps: obtaining a historical process data set of a coal-fired boiler, training a dynamic measurement and prediction model based on the historical process data set, and obtaining a trained dynamic measurement and prediction model; acquiring real-time process data of the coal-fired boiler and a working condition weight of a previous moment corresponding to the real-time process data; and inputting the real-time process data and the working condition weight of the previous moment corresponding to the real-time process data into the trained dynamic measurement and prediction model to obtain a real-time nitrogen oxide concentration estimated value. According to the embodiment of the invention, the working condition weight of the previous moment is introduced as model input, so that the dynamic measurement prediction model can effectively capture the dynamic association and evolution rule of the working condition state in the time sequence, and the accuracy and reliability of the real-time soft measurement estimation value of the nitrogen oxide concentration of the coal-fired boiler are effectively improved.

The waste gas treatment method comprises the following steps: according to the concentration of target gas collected by a first collector and the concentrations of methane and hydrogen collected by a second collector, adjusting the concentrations of methane and air to a first target concentration, the first target concentration is matched with the concentration of the target gas; according to the concentration, collected by the fourth collector, of the target gas, whether the concentration meets a preset condition or not is judged, and the input air concentration is regulated and controlled according to the preset condition. The concentration of the nitrogen oxide is matched by dynamically adjusting the concentration of the methane and the air, and an efficient reaction system for reducing the nitrogen oxide by the methane can be constructed in a plasma reaction zone under the condition of no adsorbent, catalyst or reducing agent. Methane and nitric oxide are enabled to fully react in a plasma environment, and reduction removal of the nitric oxide is directly realized.

The invention discloses a fire grate, a combustor and a water heater, and relates to the technical field of water heaters, the fire grate comprises a fire grate body, the fire grate body is provided with a mixing cavity, a first air inlet flow channel and a second air inlet flow channel, the mixing cavity is provided with an air outlet, and the air inlet end of the first air inlet flow channel is provided with an injection opening used for introducing air and fuel gas; the exhaust end of the first air inlet flow channel is communicated with a mixing cavity, the air inlet end of the second air inlet flow channel is provided with an air inlet used for introducing air, the exhaust end of the second air inlet flow channel is communicated with the first air inlet flow channel, and the second air inlet flow channel is used for jetting flow to the first air inlet flow channel. A jet flow angle is formed between the jet flow direction of the second gas inlet flow channel and the gas conveying direction of the first gas inlet flow channel, and the jet flow angle is larger than 45 degrees and not larger than 70 degrees. And the combustion head part is arranged at the air outlet, and the combustion head part is provided with a fire hole communicated with the mixing cavity. According to the technical scheme provided by the invention, emission of carbon monoxide and nitrogen oxide can be reduced.

A system, method, and apparatus for zero or low NOx emissions during a certain operating period are provided. A system can include an aftertreatment system including a catalyst. The system can include a pump coupled to at least an intake of an engine and an exhaust of the engine. The system can include a heater positioned downstream of the engine. The system can further include a controller coupled to at least the aftertreatment system. the pump, and the heater. During a warmup period for the aftertreatment system. the controller is configured to maintain the engine in an off state. initiate the heater to increase a temperature of the aftertreatment system while the engine is in the off state. and control the pump to generate an airflow directed from the intake to the heater to increase the temperature of the aftertreatment system.

The invention discloses an integrated treatment method and system suitable for multi-component industrial waste gas, and relates to the technical field of industrial waste gas treatment, and the method comprises the steps of S1, waste gas pretreatment, S2, pre-oxidation and sulfur fixation, S3, thermal oxidation, S4, non-quenching temperature self-adaptive adjustment, S5, selective catalytic reduction denitration, S6, emission and monitoring, and S7, intelligent dynamic system control. The gradient temperature field of the heat storage ceramic body is used for providing accurate and stable air inlet temperature for the SCR reaction, an independent quenching device is omitted, and therefore the comprehensive energy consumption and the operation cost of the system are greatly reduced, and by additionally arranging the pre-oxidation layer and adopting the dual-function SCR catalyst, the heat storage effect of the system is greatly improved. The system effectively realizes advanced fixation of organic sulfur and efficient removal of nitrogen oxides, dynamically adjusts the ammonia injection amount and combustion intensity, ensures that the system can still maintain extremely high treatment efficiency and stability under flow fluctuation and complex working conditions, reduces ammonia escape to the greatest extent, and is convenient to use.

An exhaust aftertreatment system (10) in the exhaust stream of an internal combustion engine (12) that is at least partially powered by an alcohol fuel is permeable to an exhaust stream containing nitrogen oxides as well as an alcohol and / or formaldehyde. The exhaust aftertreatment system (10) comprises a metering device (14) for metering ammonia into the exhaust stream, a first SCR catalyst (16), and a second SCR catalyst (18), wherein the first SCR catalyst (16) is arranged in the exhaust stream downstream of the metering device (14) and is configured to generate a treated exhaust stream from the exhaust stream of the internal combustion engine (12) that contains nitrogen oxides and at least one nitrogen-containing hydrocarbon compound.The second SCR catalyst (18) is arranged in the exhaust stream downstream of the first SCR catalyst (16) and is designed to reduce the nitrogen oxides contained in the generated treated exhaust stream by consuming the nitrogen-containing hydrocarbon compound contained in the generated treated exhaust stream. Furthermore, a method for exhaust aftertreatment and the use of an exhaust aftertreatment system (10) are specified.

An exhaust aftertreatment system (10) in the exhaust stream of an internal combustion engine (12) that is at least partially powered by an alcohol fuel is permeable to an exhaust stream from the internal combustion engine (12) containing nitrogen oxides as well as an alcohol and / or formaldehyde. The exhaust aftertreatment system (10) comprises an oxidation catalyst (14) for removing methanol and formaldehyde from the exhaust stream, an SCR catalyst (18), and a metering device (16) for metering ammonia into the exhaust stream, wherein the oxidation catalyst (14) is arranged in the exhaust stream upstream of the SCR catalyst (18). The metering device (16) is arranged in the exhaust stream upstream of the SCR catalyst (18) and upstream or downstream of the oxidation catalyst (14). Furthermore, a method for exhaust aftertreatment and the use of the exhaust aftertreatment system (10) are specified.

The invention discloses a device and a detection method for online oxidation-enrichment-reduction determination of nanogram-level nitrogen isotopes in a solid, and belongs to the technical field of nitrogen isotope analysis. The device comprises an oxidation system, a nitrogen oxide enrichment system, a nitrogen reduction system, a mass spectrum interface system, a stable isotope ratio mass spectrometer and pipelines for connecting all parts of the device. The device provided by the invention greatly reduces the quantitation limit of the nitrogen isotope in the solid sample, can realize high-precision determination of the nanogram-level nitrogen isotope in the solid sample, and has the advantages of simplicity and convenience in operation, high accuracy and the like.

The present invention relates to a urea injection amount control method, device, electronic device, and computer storage medium, belonging to the technical field of engine exhaust purification. The method comprises: obtaining a first nitrogen oxide measurement value at an SCR system inlet, a second nitrogen oxide measurement value at an SCR system outlet, and a calculated ammonia concentration value at the SCR system outlet; calculating a calculated nitrogen oxide concentration value at the SCR system outlet based on the second nitrogen oxide concentration measurement value and the calculated ammonia concentration value, and calculating a nitrogen oxide conversion efficiency based on the first nitrogen oxide concentration measurement value and the calculated nitrogen oxide concentration value; calculating a urea injection amount correction factor and a nitrogen oxide conversion efficiency correction factor based on the calculated ammonia concentration value at the SCR outlet, the calculated nitrogen oxide conversion efficiency value, and a preset nitrogen oxide conversion efficiency target value, and adjusting the urea injection amount. The present invention can improve the accuracy of the final urea injection control, reduce nitrogen oxide emissions, and reduce ammonia leakage.

The invention provides a celluloid nitrocotton stability quantitative determination method based on conductivity analysis, and the method comprises the following steps: determining the conductivity of standard nitrogen oxide gas dissolved in an aqueous solution by adopting a conductivity meter through a standard gas simulation mode according to the criterion of Beckmann-Lockg method 2mL / g; taking the numerical value as a stability index critical value of the celluloid nitrocotton; the method comprises the following steps: absorbing nitrocotton with the same mass by using ultrapure water, heating at 132 DEG C for 2 hours, releasing nitrogen oxide gas, recording the change value of the conductivity in the solution along with time in real time by using an oxidation stability tester, obtaining the change value of the conductivity after 2 hours, and determining the content of nitrogen oxide according to the comparison between the conductivity value and a critical value. And judging whether the stability of the celluloid nitrocotton sample is qualified or not. The method provided by the invention can solve the technical problem that accurate quantitative judgment is difficult to realize due to large sample quantity, high safety risk, tedious operation process and large color change error of test paper observed by human eyes in the traditional method.

The utility model belongs to the technical field of combustion, and particularly discloses a fire grate and a combustor. The fire grate comprises an inner shell, a rectification inner core and an outer shell assembly. Two inner rectifying plate parts are arranged at the upper end of the inner shell; the rectification inner core is inserted between the two inner rectification plate parts and is provided with a plurality of rectification inner plates, the two rectification inner plates on the outermost side are attached to the adjacent inner rectification plate parts, a first flame channel is formed between every two adjacent rectification inner plates, and the lower end of each first flame channel communicates with the corresponding first injection channel; second flame channels are formed in the positions, on the two opposite sides of the inner shell, of the outer shell assembly, an air channel is formed between the outer shell assembly and the inner shell, a communicating structure is arranged between the inner shell and the outer shell assembly, and the second flame channels communicate with the second injection channel through the communicating structure. According to the utility model, the combustion sufficiency can be improved, the local high temperature generated by combustion is reduced, and nitrogen oxides generated by combustion are reduced.

The invention relates to a Ru / CeO2 passive nitrogen oxide adsorbent as well as a preparation method and application thereof. The Ru / CeO2 passive nitrogen oxide adsorbent comprises the following components in percentage by weight: 0.1 to 5.0 percent of Ru and 95.0 to 99.9 percent of CeO2. The Ru / CeO2 adsorbent is prepared by adopting an excessive impregnation method, and the specific method is as follows: adding the prepared CeO2 carrier into a ruthenium nitrate solution, adding deionized water for dilution, stirring for 10-15 hours at normal temperature, then carrying out rotary evaporation on the mixed solution at 60-80 DEG C, drying for 6-12 hours in a drying oven at 60-120 DEG C, and finally roasting for 2-6 hours in an air atmosphere at 400-600 DEG C. The adsorbent is used for treating NOx-containing tail gas. Compared with the prior art, the adsorbent disclosed by the invention has the advantages that the adsorption capacity at 80 DEG C is up to 299 mu mol / g, the adsorbent is efficiently desorbed at 200-500 DEG C, the desorption capacity is up to 285 mu mol / g, and the adsorbent has excellent water-resistant and CO-resistant performance and cycling stability. The desorption temperature window of the Ru / CeO2 adsorbent is highly matched with the subsequent selective catalytic reduction (SCR) of nitrogen oxides, and the Ru / CeO2 adsorbent is matched with the subsequent SCR to realize efficient degradation of the nitrogen oxides, so that the Ru / CeO2 adsorbent has a wide application prospect.

The invention relates to the technical field of boiler pulverized coal monitoring, in particular to a boiler pulverized coal monitoring method which comprises the following steps: determining whether a separation mode of a pulverized coal separator is qualified or not according to a comparison result of a particle size distribution characterization value of pulverized coal in a pulverized coal pipe at an outlet of a coal mill and a preset distribution characterization value; under the condition that the separation mode of the pulverized coal separator is determined to be unqualified, the angle of a guide blade of the pulverized coal separator is adjusted according to the radial flow velocity difference value of the pulverized coal pipe at the outlet of the coal mill; whether airflow mixing of the thick pulverized coal phase and the thin pulverized coal phase is qualified or not is determined based on the ignition interval; under the condition that airflow mixing is determined to be unqualified, a plurality of air speed adjusting coefficients are set according to the uniformity characterization value of temperature gradient distribution of the hearth to adjust the air speed of secondary air, and the air speed adjusting coefficients are optimized according to the flame shape characterization value in the hearth; and optimizing the preset distribution characterization value according to the fluctuation intensity of the combustion efficiency curve. The combustion efficiency of the pulverized coal is guaranteed while generation of nitric oxide is inhibited.

The invention provides a dual-fuel low-nitrogen combustor. The dual-fuel low-nitrogen combustor comprises a central ignition unit, a premixing air duct, a fuel distribution unit and a combustion-supporting air distribution unit. The premixing air cylinder comprises an outer cylinder, a center hole and n premixing cylinders. The center ignition unit penetrates through the center hole, and the n premixing barrels are distributed on the periphery of the center air pipe in an array mode along the circumference, so that the whole fire outlet interface of the premixing air barrels is fully utilized, the uniformity and stability of flames are improved, and generation of nitric oxide is reduced. The fuel distribution barrel is divided into four cavities through axial front-back separation and radial inner-outer separation, the structure is compact, and fuel can be evenly and stably distributed to all the injection pipes. According to the invention, two fuels with high and low calorific values can be adopted, and the two fuels do not interfere with each other, operate independently, can be used at the same time and can also be used independently, so that the selectivity of the fuels is relatively wide. The flame structure can be kept the same, and application occasion adaptability is improved.

The utility model belongs to the technical field of ethylene glycol preparation, and particularly relates to an esterification purge gas treatment device in a process of preparing ethylene glycol from synthesis gas, which comprises an MN recovery tower, a gas mixer, a tail gas heater, a tail gas reactor, a cooler and a tail gas absorption tower, tower top outlet gas of the MN recovery tower and purge gas from PSA desorption gas of a hydrogenation unit enter a gas mixer, are mixed in the gas mixer, then enter a tail gas heater to be heated and then enter a tail gas reactor to react, an outlet of the tail gas reactor is connected with an inlet of a cooler, an outlet of the cooler is connected with a tail gas absorption tower, and an outlet of the tail gas absorption tower is connected with an outlet of the MN recovery tower. The tail gas absorption tower is connected with a spray water inlet pipe and a waste gas discharge pipe; and the tail gas reactor is a fixed tubular reactor. According to the device, nitrogen oxide which cannot be directly discharged in esterification purge gas can react to generate harmless gas such as nitrogen and nitrogen dioxide, environmental pollution is avoided, the device can adapt to the shutdown working condition of an esterification system, air does not need to be supplemented to the MN recovery tower, and the technological operation risk is reduced.

To provide a method for producing formaldehyde capable of reducing negative influence on catalysts and the like during a process for producing formaldehyde by using methanol.SOLUTION: A method for producing formaldehyde using methanol as a raw material, the methanol containing nitrogen oxides, wherein the concentration of NO2 in the methanol, as detected by ion chromatographic analysis, is 0.002 mass ppm or more and 100 mass ppm or less.SELECTED DRAWING: Figure 1