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HJ 1178-2021 English PDF

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HJ 1178-2021: (Guidelines for feasible technologies for pollution prevention and control of industrial boilers)
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Basic data

Standard ID HJ 1178-2021 (HJ1178-2021)
Description (Translated English) (Guidelines for feasible technologies for pollution prevention and control of industrial boilers)
Sector / Industry Environmental Protection Industry Standard
Word Count Estimation 17,132
Issuing agency(ies) Ministry of Ecology and Environment

HJ 1178-2021: (Guidelines for feasible technologies for pollution prevention and control of industrial boilers)


---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.
(Guidelines for feasible technologies for pollution prevention and control of industrial boilers) National Ecological Environment Standard of the People's Republic of China Guidance on Feasible Technologies for Pollution Prevention and Control of Industrial Boilers Guideline on available techniques of pollution prevention and control for industrial boiler This electronic version is the official standard text, which is reviewed and typeset by the Environmental Standards Institute of the Ministry of Ecology and Environment. Published on 2021-05-12 2021-05-12 Implementation Released by the Ministry of Ecology and Environment directory Foreword...ii 1 Scope...1 2 Normative references...1 3 Terms and Definitions...1 4 Heat production process and pollutant generation...2 5 Pollution Prevention Techniques...2 6 Pollution control technology...3 7 Environmental management measures...7 8 Possible technologies for pollution prevention...8 Appendix A (Informative Appendix) Typical Industrial Boiler Thermal Production Process and Main Pollution-Producing Nodes...12 Appendix B (informative appendix) Concentration of flue gas pollutants at the furnace outlet of typical industrial boilers...14 Guidance on Feasible Technologies for Pollution Prevention and Control of Industrial Boilers

1 Scope of application

This standard proposes feasible technologies for the prevention and control of waste gas, waste water, solid waste and noise pollution of industrial boilers. This standard can be used as a single steam boiler with an output of 65 t/h and below using coal, oil, gas and biomass briquette fuel as fuel, various capacity Environmental impact assessment of industrial production and civil heating boiler construction projects such as hot water boilers and organic heat carrier boilers, layer-fired boilers of various capacities, etc. price, the formulation and revision of national pollutant discharge standards, the management of pollutant discharge permits and the selection of pollution prevention and control technologies. When selecting pollution prevention technologies for industrial boilers using briquette, coal-water slurry, coal gangue, petroleum coke, oil shale and other fuels, refer to this standard The feasible technologies for pollution prevention and control of coal-fired boilers in Zhunzhong; this standard may be referred to when selecting pollution prevention and control technologies for industrial boilers using alcohol-based liquid fuels Feasible technologies for pollution prevention and control of medium oil boilers. This standard does not apply to pollution prevention and control of industrial boilers fueled by domestic waste and hazardous waste.

2 Normative references

This standard refers to the following documents or clauses thereof. For dated references, only the dated version applies to this standard. For undated references, the latest edition (including all amendments) applies to this standard. GB 8978 Integrated Wastewater Discharge Standard GB 12348 Industrial Enterprise Boundary Environmental Noise Emission Standard GB 13271 Boiler Air Pollutant Emission Standard GB 16297 Comprehensive Emission Standard of Air Pollutants GB 18597 Hazardous Waste Storage Pollution Control Standard GB 18599 General Industrial Solid Waste Storage and Landfill Pollution Control Standard "Administrative Measures for Automatic Monitoring of Pollution Sources" (Order No. 28 of the State Environmental Protection Administration) "Notice on Issuing the Catalogue of Highly Polluting Fuels" (Guohuanqiqiqi [2017] No. 2) "Measures for the Administration of Hazardous Waste Transfer Forms" "National Hazardous Waste List"

3 Terms and Definitions

The following terms and definitions apply to this standard. 3.1 boiler boiler Use the heat energy or other heat energy released by fuel combustion to heat hot water or other working fluids to produce specified parameters (temperature, pressure) and quality steam, hot water or other working fluid equipment. Note. The rated output (heat production) of the boiler is generally expressed in two units, namely thermal power and evaporation. Thermal power in megawatts (MW), evaporation The unit of quantity is ton/hour (t/h). The heat production of 0.7 MW is equivalent to the evaporation of 1 t/h. 3.2 available techniques of pollution prevention and control According to my country's environmental demand and economic level in a certain period of time, comprehensive use of pollution prevention technology and pollution control technology in the process of pollution prevention and control technology and environmental management measures to stably meet the national pollutant discharge standards and large-scale application of technology.

4 Heat production process and pollutant generation

4.1 Thermal production process 4.1.1 The boiler heat production process mainly includes combustion system, storage system, preparation and transportation system, auxiliary system and pollution control system Wait. See Appendix A for the typical boiler thermal production process and main pollution-producing nodes. 4.1.2 The combustion methods of the combustion system mainly include bed combustion (layer combustion furnace represented by chain furnace and coal thrower furnace), fire chamber combustion (chamber combustion furnace), fluidized bed combustion (fluidized bed furnace); the storage system mainly includes fuel silo/storage tank, fuel storage yard, fly ash warehouse, desulfurization by-product warehouse, ash slag yard, etc.; preparation and conveying system mainly includes fuel preparation device, fuel feeding device, fuel conveying device, etc.; auxiliary system Mainly includes softened water preparation system and cooling water system; pollution prevention system mainly includes waste gas, waste water, solid waste and noise pollution prevention and control system, etc. 4.1.3 Fuels mainly include coal, oil, natural gas and biomass briquette fuel. 4.1.4 The chemicals used in the boiler heat production process mainly include desulfurizers (limestone, lime, magnesium oxide, magnesium hydroxide, hydrogen Sodium oxide, sodium carbonate, etc.), denitration reducing agents (urea, ammonia, etc.) and water treatment agents (coagulants, coagulants, flocculants, etc.). 4.2 Generation of pollutants 4.2.1 The pollutants in the exhaust gas mainly include particulate matter, sulfur dioxide (SO2), nitrogen oxides (NOx), mercury and its compounds. of which Particulate matter mainly comes from combustion system, storage system, preparation and delivery system; SO2, NOx, mercury and their compounds are produced in combustion system. See Appendix B for the concentration of flue gas pollutants at the furnace outlet of typical industrial boilers. 4.2.2 Wastewater mainly includes production waste water such as wet desulfurization waste water, softened water regeneration waste water and boiler sewage. 4.2.3 Solid wastes mainly include general industrial solid wastes such as fly ash, slag, desulfurization by-products, waste vanadium-titanium catalysts, waste ion exchange Replace resins, etc., which are included in the "National Hazardous Waste List" or are identified as dangerous according to the identification standards and identification methods of hazardous wastes stipulated by the state. characteristic hazardous waste. 4.2.4 The noise mainly comes from the combustion system (blower, etc.), preparation and conveying system (coal mill, crusher, belt conveyor, etc.), Pollution prevention system (booster fan, desulfurizer circulating pump, etc.) and auxiliary systems (process water pump, etc.).

5 Pollution Prevention Technologies

5.1 General principles 5.1.1 Boiler users should give priority to the use of low-sulfur and low-ash fuels that meet relevant national or local standards and policy requirements to reduce fuel consumption. Concentrations of particulate matter, SO2, mercury and their compounds from fuel combustion. 5.1.2 The boiler user should choose the furnace type and combustion equipment with good low nitrogen combustion effect. 5.1.3 The boiler user shall strengthen the regular maintenance and maintenance of the low-nitrogen combustion equipment to ensure its stable operation. 5.2 Low nitrogen combustion technology 5.2.1 Low-nitrogen combustion equipment is the carrier of low-nitrogen combustion technology. The low-nitrogen combustion technology mainly includes low-nitrogen burners, overall air classification in the furnace Combustion technology, flue gas recirculation technology, etc., have the characteristics of low investment cost and convenient operation and maintenance. When using this technology, it should also be coordinated to control Products of incomplete combustion of carbon such as carbon monoxide. 5.2.2 Low-nitrogen burners are suitable for chamber furnaces and can be classified into diffusion burners (including fuel-graded low-nitrogen burners, air gas staged low nitrogen burners) and premixed burners. 5.2.2.1 Through the optimization of the physical structure, the diffusion burner stratifies and feeds the air and fuel into the furnace to realize staged combustion, expanding the Combustion area, lower flame temperature, reduce NOx generation. Coal, oil, natural gas, coke oven gas using diffusion burners The NOx concentration of boilers burning blast furnace gas can be controlled at.200-600 mg/m3, 100-300 mg/m3, 60-200 mg/m3, 200～500 mg/m3 and 30～200 mg/m3. 5.2.2.2 Premixed burners are suitable for natural gas-fired boilers. According to the principle of reducing NOx generation, they can be divided into lean-burn premixed combustion technology and water Cold premixed combustion technology. The lean premixed burner uses high excess air to reduce the flame temperature, and the burner is divided into structures such as metal fibers Flame, stable combustion can make temperature distribution uniform and reduce NOx generation; using this technology, NOx generation concentration can be controlled at 20 ~ 80 mg/m3. The water-cooled premixed burner uses indirect cooling to remove the heat at the root of the flame from the high temperature area, reducing the temperature of the premixed flame and reducing NOx Generated; using this technology, the NOx production concentration can be controlled at 20 ~ 50 mg/m3. 5.2.3 Furnace overall air staged combustion technology is suitable for layered furnaces, coal-fired chamber furnaces and oil-fired chamber furnaces. The air required for combustion is fed into the combustion flame or fire bed step by step, so that the fuel is burnt in stages and stages in the furnace to reduce the generation of NOx. using this technology The NOx generation concentration of the layer-burning furnace, coal-burning chamber furnace and oil-burning chamber furnace can be controlled at.200-400 mg/m3 and.200-400 mg/m3 respectively. and 100 to 300 mg/m3. 5.2.4 The flue gas recirculation technology is suitable for fluidized bed furnaces, laminar furnaces and chamber furnaces. By using the low-temperature flue gas at the boiler tail as an inert heat sink The working fluid is introduced into the flame zone, which reduces the temperature of the flame zone and the oxygen content in the combustion zone, slows down the rate of combustion heat release, and reduces the generation of NOx. the technology The technology is often used in combination with other low-nitrogen combustion technologies.

6 Pollution control technology

6.1 Flue gas pollution control technology 6.1.1 General principles 6.1.1.1 The boiler user shall give priority to adopting pollution prevention technology according to the actual situation. governance technology. 6.1.1.2 Coal-fired boilers should adopt bag type dust removal, electrostatic dust removal, electric bag composite dust removal, mechanical dust removal bag type dust removal and other technologies to achieve particulate matter removal. standard discharge. When the concentration of particulate matter at the furnace outlet of oil-fired boilers and gas-fired boilers does not meet the standard, bag-type dust removal technology should be used to achieve standard discharge. Burning The material briquette fuel boiler should adopt the mechanical dust bag dust removal technology to achieve the emission of particulate matter up to the standard. 6.1.1.3 The limestone/lime-gypsum wet method, magnesium method, sodium-alkali method, flue gas circulating fluidized bed method and in-furnace calcium injection desulfurization technology should be adopted for coal-fired boilers. technology to achieve SO2 emission standards. If the boiler user has a stable source of waste alkali (such as alkaline wastewater, etc.) The gas desulfurization method realizes the SO2 emission standard. When the SO2 emission of oil-fired, gas-fired and biomass-fired briquette fuel boilers does not meet the standard, it is advisable to refer to coal-fired boilers. The boiler chooses flue gas desulfurization technology. 6.1.1.4 Nitrogen oxide emission control should give priority to using low-nitrogen combustion technology. If the emission standard cannot be achieved, it should be combined with selective catalytic reduction. SCR, selective non-catalytic reduction (SNCR) and SNCR-SCR combined denitrification technology to achieve emission standards. 6.1.1.5 Mercury and its compounds should be discharged up to standard by adopting collaborative treatment technology. 6.1.2 Particulate Matter Control Technology 6.1.2.1 Dry electrostatic precipitator technology Through reasonable design of parameters such as flue gas flow rate and specific dust collection area, the dust removal efficiency is 96% to 99.9%. The flue gas flow rate should be 0.8～ 1.2 m/s, when the specific dust collection area is not less than 100 m2/(m3/s), the particle concentration at the outlet of the dry electrostatic precipitator can reach below 50 mg/m3; When the specific dust collection area is not less than 110 m2/(m3/s), the particle concentration at the outlet of the dry electrostatic precipitator can reach below 30 mg/m3.This technology is suitable for It is used for the removal of particulate matter from coal-fired boilers with a specific resistance between 1×104 and 1×1011 Ω·cm. And the removal effect of fine particles is poor; the system resistance is small, the floor space is relatively large, and the investment cost is relatively high. 6.1.2.2 Bag dust removal technology Through reasonable selection of filter material types, filter wind speed and other parameters, the dust removal efficiency is 99% to 99.99%. When using conventional needle felt filter media, When the filtering wind speed is not more than 1.0 m/min, the particle concentration at the outlet of the bag filter can reach below 30 mg/m3; when the filtering wind speed is not more than 30 mg/m3 At 0.9 m/min, the particle concentration at the outlet of the bag filter can reach below 20 mg/m3.When using high-precision filter media, the filtering wind speed should not be greater than At 0.8 m/min, the particle concentration at the outlet of the bag filter can reach below 10 mg/m3.When dealing with high powder after flue gas circulating fluidized bed desulfurization When the dust concentration is flue gas, the filtering wind speed should not be greater than 0.7 m/min. The technology is basically free from changes in coal type, soot specific resistance and flue gas working conditions and other influences, the operating temperature should be higher than the acid dew point by more than 15 °C and ≤250 °C; Protection measures to reduce the risk of filter bag burning; relatively large system resistance, small footprint, low investment cost, and high filter bag replacement cost. 6.1.2.3 Wet electrostatic precipitator technology This technology is often used after flue gas desulfurization. By reasonably designing parameters such as flue gas flow rate and specific dust collection area, the dust removal efficiency is 60% to 90%. The concentration of particulate matter at the outlet of the wet electrostatic precipitator can reach below 10 mg/m3.The technology is divided into plate wet electrostatic precipitator technology and honeycomb wet electrostatic precipitator Dust technology can effectively remove fine particles and droplets entrained in flue gas after wet desulfurization, and efficiently and collaboratively remove sulfur trioxide (SO3), mercury and its compounds; small system resistance, small footprint and high investment cost. 6.1.2.4 Electric bag composite dust removal technology Through reasonable selection of filter material types and reasonable design of parameters such as the filtering wind speed and the specific dust collecting area of the electric area, the dust removal efficiency of 99%~ 99.99%. When using conventional needle felt filter material, the emission concentration of particulate matter can reach below 20 mg/m3; when using high-precision filter material, particulate matter emission The emission concentration can reach below 10 mg/m3.This technology is suitable for the removal of particulate matter from the flue gas of coal-fired boilers, and has both bag-type dust removal and dry electrostatic dust removal. The advantages of the filter bag are that the filter bag has a long service life and has a good removal effect on difficult-to-charge particles, fine particles and high specific resistance dust; the system has large resistance and occupies a large area. Large area, high investment cost, and high filter bag replacement cost. 6.1.3 Sulfur dioxide treatment technology 6.1.3.1 Limestone/lime-gypsum wet desulfurization technology Using limestone or lime slurry as the desulfurizer, the desulfurization can be achieved by controlling the flue gas flow rate, calcium-sulfur molar ratio and liquid-gas ratio in the tower. The sulfur efficiency is 90%-99%, and the SO2 emission concentration can be controlled at 25-200 mg/m3.The technology is suitable for pots of various fuels, furnace types and capacities Furnace flue gas SO2 treatment has strong adaptability to changes in coal type and load, and has a synergistic treatment effect on particulate matter, mercury and its compounds; it is necessary to consider desulfurization waste For the treatment and disposal of water and desulfurization by-products, the system investment cost is relatively high; the system resistance and area are relatively large. 6.1.3.2 Magnesium-based desulfurization technology The magnesium hydroxide slurry or the magnesium hydroxide slurry formed by the aging of magnesium oxide is used as the desulfurizing agent. According to the parameters such as mole ratio and liquid-gas ratio, the desulfurization efficiency is 90%-99%, and the SO2 emission concentration can be controlled at 25-200 mg/m3.This technology is suitable for It is used for SO2 treatment of boiler flue gas of various fuels, furnace types and capacities in areas rich in magnesium ore resources, and has strong adaptability to changes in coal type and load; Consider the desulfurization wastewater treatment and the resource utilization of desulfurization by-products; the system has small resistance, small footprint, low investment cost, and absorbent consumption costs Ben High. 6.1.3.3 Sodium-alkali desulfurization technology Using sodium-based substance solutions such as sodium hydroxide or sodium carbonate as the desulfurizing agent, by controlling the flue gas flow rate, reaction molar ratio, and liquid-gas ratio in the tower and other parameters, the desulfurization efficiency is 90% to 99%, and the SO2 emission concentration is controlled at 25 to.200 mg/m3.The technology is suitable for a variety of fuels, furnaces Type and capacity boiler flue gas SO2 treatment, the absorbent has high reactivity; effective measures should be taken to reduce soluble salt emissions into the atmosphere; system resistance Small force, small footprint, low investment cost, and relatively high absorbent consumption cost. 6.1.3.4 Flue gas circulating fluidized bed desulfurization technology Calcium-based desulfurizer is used, and by controlling parameters such as calcium-sulfur molar ratio and flue gas residence time, the desulfurization efficiency is 80% to 95%, and the SO2 emission The concentration can be controlled at 35 ~.200 mg/m3.The technology is suitable for coal-fired boilers that use medium and low sulfur coal or coal-fired streams that have been desulfurized in the furnace. The chemical bed boiler consumes less water; the calcium sulfite content in the desulfurization by-product is high, and the resource utilization is limited; The collapsed bed problem that may exist during load operation; the system resistance and floor space are large, and the investment cost and absorbent cost are high. 6.1.3.5 In-furnace desulfurization technology The limestone powder is used as the desulfurizing agent, and SO2 in the flue gas is removed by spraying the desulfurizing agent into the furnace. By reasonably matching the desulfurizing agent injection area parameters such as temperature, calcium-sulfur ratio and desulfurizer particle size, the desulfurization efficiency can reach 50%; when burning coal with sulfur content not more than 0.5%, the furnace outlet SO2 concentration up to.200 mg/m3.This technology is mostly used in fluidized bed furnaces, and is combined with external wet or flue gas circulating fluidized bed desulfurization systems. Low capital cost, simple configuration, low energy consumption and small footprint; there are some problems such as reducing boiler thermal efficiency, increasing furnace wear and high operating material consumption, etc. question. 6.1.4 Nitrogen oxide treatment technology 6.1.4.1 SNCR Denitrification Technology Using ammonia water, urea, etc. as denitration reducing agents, by selecting reasonable reaction temperature range, ammonia-nitrogen molar ratio and other parameters, the layer combustion furnace and chamber combustion The denitration efficiency of the furnace can be controlled at 20% to 40%, and the denitration efficiency of the fluidized bed furnace can be controlled at 40% to 70%. The technology is applied to layer-fired furnaces, chamber-fired For furnace and fluidized bed furnace, the NOx emission concentration can be controlled at 120-200 mg/m3, 120-300 mg/m3 and 90-200 mg/m3 respectively. Should The technical reaction temperature is usually 800 to 1150 °C, which is suitable for coal-fired and biomass-fired briquette fuel boilers, with small footprint, investment cost and transportation. The operation cost is low; the escape mass concentration of ammonia should be controlled to be less than 8 mg/m3. 6.1.4.2 SCR denitration technology Ammonia, urea, etc. are used as denitration reducing agents, under the action of catalyst, by selecting a reasonable reaction temperature region and rationally designing the ammonia nitrogen friction The denitration efficiency can be controlled at 50% to 90%, and the NOx emission concentration can be controlled at 40～ 150 mg/m3.The denitration catalyst of this technology is mainly in the form of honeycomb type or plate type, and the reaction temperature of the catalyst is usually 300-420℃; The efficiency is relatively high and the load adaptability is strong; the system resistance is large, the floor space is large, the investment cost and operation cost are high; the ammonia fugitive quality should be controlled If the concentration is lower than 2.28 mg/m3, the SO2/SO3 conversion rate should be controlled to be lower than 1%. 6.1.4.3 SNCR-SCR combined denitrification technology Ammonia, urea, etc. are used as denitration reducing agents, by selecting a reasonable reaction temperature range, ammonia-nitrogen molar ratio, catalyst activity, catalyst According to parameters such as the number of layers, the denitration efficiency can be controlled at 50% to 90%, and the NOx emission concentration can be controlled at 40 to 150 mg/m3.The technical SNCR area The reaction temperature in the SCR region is usually 800-1150°C, and the catalyst reaction temperature in the SCR region is usually 300-420°C; suitable for coal-fired and biomass-fired High quality briquette fuel boiler, large system resistance and floor space, investment cost and operating cost are between SNCR and SCR, ammonia injection accuracy The requirements are high, and the catalyst wear is relatively large; the new project should control the ammonia escape mass concentration to be less than 2.28 mg/m3, and the renovation project should control the ammonia escape mass concentration. The concentration should be lower than 3.8 mg/m3; the conversion rate of SO2/SO3 should be controlled to be lower than 1%. 6.2 Wastewater pollution treatment technology 6.2.1 Main production wastewater classification and treatment technologies 6.2.1.1 Desulfurization wastewater treatment Desulfurization wastewater is the wastewater discharged from the wet desulfurization process, which has the characteristics of high chloride ion concentration and high suspended solids concentration. Reuse or indirect discharge after adjustment, sedimentation, flocculation, clarification and concentration. 6.2.1.2 Demineralized water regeneration wastewater treatment The softened water regeneration wastewater is the wastewater generated during the regeneration of the boiler softening water device. When it is acid-base wastewater, it should be treated with pH adjustment. Reuse or discharge to the centralized production wastewater treatment system for centralized treatment; when it is concentrated brine, it should be reused or discharged to raw water after flocculation and clarification. Centralized treatment of waste water centralized treatment system. 6.2.1.3 Boiler sewage treatment Boiler sewage is the sewage that needs to be discharged regularly or continuously in order to maintain the water quality in the boiler. It should be treated by pH adjustment, flocculation and clarification. It is reused or discharged to the centralized production wastewater treatment system for treatment. 6.2.2 Centralized Treatment Technology of Production Wastewater Collect and store various production waste water such as softened water regeneration waste water and boiler sewage. Reuse or indirect discharge after centralized treatment such as clarification and concentration. 6.3 Solid waste treatment technology 6.3.1 Disposal 6.3.1.1 Solid waste shall be stored in accordance with the requirements of GB 18597 or GB 18599 according to its waste properties. 6.3.1.2 General industrial solid waste should be used as a resource first, and if it cannot be used as a resource, it should be disposed of in accordance with the provisions of GB 18599. 6.3.1.3 Hazardous waste should be entrusted to qualified units for utilization and disposal. The processes of production, collection, storage, transportation, utilization and disposal should be Meet the provisions of relevant laws, regulations and standards for hazardous waste, and submit relevant information through the National Solid Waste Management Information System. Danger The waste transfer process shall implement the "Management Measures for the Transfer of Hazardous Wastes". 6.3.2 Resource utilization 6.3.2.1 Fly ash can be used to make cement, bricks and other building materials, as well as concrete admixtures, road subgrade treatment, etc. 6.3.2.2 Desulfurized gypsum can be used to make gypsum board, used as cement retarder, and can also be used for mine backfill, soil improvement, etc. 6.3.2.3 Discarded filter bags can be recycled according to the material of the filter bags by mechanical crushing, melting and wire drawing by returning to the furnace, high temperature cracking, etc. use. 6.4 Noise control technology 6.4.1 Muffler Refers to the airflow duct with sound-absorbing lining or special shape, which can effectively reduce aerodynamic noise, and the noise reduction effect is about 15-25 dB (A); It is suitable for the control of the exhaust port noise of various types of fans and coal mills. The muffler should be installed near the exhaust port or at the sensitive point of the environment. 6.4.2 Sound insulation Use walls, doors and windows, sound insulation covers and other components to block the spread of noise. When sound insulation is applied to fixed noise sources, it should be as close as possible to Noise source set sound insulation cover, noise reduction effect...

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