| Efficient Ammonia
Desulfurization (EADS) Technology |
| Fossil fuels such as coal and oil contain a certain amount of sulfur, and the combustion produces, sulfur oxides (SOx), which is a major air pollutants. JNG (China)'s EADS process is based on the reaction between ammonia and sulfur dioxide. In the patented multi-functional ammonia desulfurization absorber, ammonia reacts with SO2 to yield ammonium sulfite/bisulfite as an intermediate product. Air is then fed into the absorber to oxidize the ammonium sulfite/bisulfate into ammonium sulfate. |
| The Integrated Ultra-clean Desulfurization and Particulate Removal Absorber is the core patented equipment of JNG (China) desulfurization system. It integrates the functions of flue gas absorption, oxidation, concentration and crystallization, demisting, and fine particulate removal. The in-situ saturation crystallization utilizes the heat from the flue gas to concentrate and crystallize ammonium sulfate, which significantly reduces the energy consumption of the system. |
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| Resource recovery type technology |
| JNG (China) has overcome the technical challenges of high ammonia recovery associated with ammonia-based desulfurization process, achieving ammonia recovery ≥ 99% with no secondary pollution. |
| Rich engineering experience and excellent performance |
| JNG (China) has completed over around two hundred projects and over three hundred installations spanning industries such as oil & gas, coal chemical, power, iron & steel and pharmaceutical. EADS technology is capable of treating flue gas with SO2 concentrations up to 30,000 mg/Nm3 and sulfur content in coal used in coal-fired boilers of 0.4%～5% with greater than 99% sulfur removal efficiency and greater than 99% ammonia recovery. |
| Customized technical solutions |
| JNG (China)'s mature, energy-saving crystallization technologies include in-situ saturation crystallization, evaporation crystallization, and saturation-evaporation crystallization. JNG (China) is also capable of designing the absorption systems using anhydrous ammonia, aqueous ammonia, or urea as the absorbent. In addition, JNG (China)'s expertise in granulation technology allows for the production of ammonium sulfate in either large or small granules to meet the market needs. |
| Waste ammonia recycling technology |
| The recovery of ammonia from the waste water generated in the oil & gas or coal chemical industries reduces waste water treatment problems and provides ammonia as the absorbent for the EADS process. |
| Integrated desulfurization and denitrification technology |
| JNG (China) has rich experience in designing and constructing SCR and SNCR denitrification systems. The integration of desulfurization and denitrification systems will further reduce the capital and operating costs. |
· SO2 emissions ≤ 35 mg/Nm3
· Particulate content ≤ 5 mg/Nm3
· Ammonia recovery ≥ 99%
· No waste water or solid waste generation |
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| Flue gas enters the desulfurization absorber and goes through cooling, scrubbing and demisting steps. The clean flue gas is then discharged from the stack. |
| Sulfur dioxide is absorbed in the absorption section of the absorber by ammonia to form ammonium bisulfate, which is subsequently oxidized into ammonium sulfate. The ammonium sulfate solution is concentrated through evaporation with the residual heat heated in the flue gas coming into the absorber. |
| Ammonium sulfate is crystallized either inside the absorber or in an external evaporative crystallizer. Customer process conditions and requirements will dictate the selection of the crystallization method. The crystallized ammonium sulfate then undergoes a series of dewatering steps which include a hydrocyclone, centrifuge, and dryer. The granulated fertilizer product is then packaged and ready to be sold in the market. |
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| JNG (China) initiated the research and development of the EADS technology in August 1998 and has successfully addressed the ammonia slip and aerosol issues, which had been the key technical challenges of the ammonia-based desulfurization process. The EADS technology has been constantly improved to help our clients meet the increasingly stringent emissions regulations. The latest (4th generation) EADS is capable of satisfying China's newly-proposed ultra-low emission regulations, in which the air pollutant emissions from coal-fired boilers/power generators must be controlled to the same level of gas-fired boiler/power generators. |
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| Ultrasound-enhanced SO2 and Particulate Control Technology (USPAC) |
| In order to further improve air quality, according to China's Action Plan of Energy saving, Emission Reduction, Upgrading and Retrofitting of Coal-Fired Power Plant (2014-2020), air pollutant emissions concentrations of newly-built coal-fired power generating units shall generally meet the emission standards for gas-fired boiler/power generators. This is known as the Ultra-low Emissions Standard, which requires dust, SO2 and nitrogen oxide concentrations in the flue gas to be lower than 10, 35 and 50 mg/Nm3, respectively. JNG (China)'s ultrasound-enhanced desulfurization and particulate removal technology is capable of controlling SO2 concentration in the treated gas to lower than 35 mg/Nm3 and PM lower than 5mg/Nm3. It has been proven to be an effective approach to achieve ultra-low emissions. |
| This enhanced technology improves the performance of the original ammonia absorption system by optimizing spray density, liquid–gas distribution and the oxidation process. In addition, fine particulates in the flue gas are agglomerated with scrubbing and ultrasound mechanisms, and are removed by our patented demister (Patent No. 2014201864177), which significantly improves the overall SO2 and PM removal efficiency. |
The USPAC technology offers the following advantages compared with a Wet Electro-Static Precipitator (WESP):
· A small footprint, integrated with the absorption system
· A simple process flow, installed within the FGD absorber
· High reliability, less maintenance
· 40% less capital cost
· 40% less operating cost, approximately 50% less power consumption
· No extra process waster cost, no waste water disposal |
| Comparison between WESP and USPAC Technology: |
| Performance of USPAC Technology |
· PM emission ≤ 5 mg/Nm3
· SO2 emission ≤ 35 mg/Nm3
· Ammonia recovery ≥ 99%
· For mist droplets ≥1 µm, the removal efficiency is over 98% |
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