Fossil fuels such as coal and oil contain a certain amount of elemental sulfur, and the combustion products, sulfur oxides (Sox), are one of the major air pollutants. JNEP’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 the fed into the absorber to oxidize the ammonium sulfite/bisulfate into ammonium sulfate.
Flue Gas System: Flue gas enters the desulfurization absorber and goes through cooling, scrubbing and delisting steps. The clean file gas is then discharged from the stack.
Absorption System: 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 from the flue gas coming into the absorber.
Ammonium Sulfate System: Ammonium Sulfate is crystallized either inside the absorber or in an external evaporative crystallizer. Customer process conditions and requirements will dictate the selection method. The crystallized ammonium 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.
Integrated Ultra-clean Desulfurization and Particulate Removal Absorber
The Integrated Ultra-clean Desulfurization and Particulate Removal Absorber is the core patented equipment of JNEP’s 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.
JNEP 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.
Reliable ammonia slip and aerosol control technology
JNEP has overcome the technical challenges of ammonia slip and aerosol generation associated with ammonia-based desulfurization process, achieving ammonia slip ≤ 3 mg/Nm3, with no secondary pollution, and ammonia recovery ≥ 99%.
Rich engineering experience and excellent performance
JNEP has completed over one hundred projects 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
JNEP’s mature, energy-saving crystallization technologies include in-situ saturation crystallization, evaporation crystallization, and saturation-evaporation crystallization. JNEP is also capable of designing the absorption systems using anhydrous ammonia, aqueous ammonia, or urea as the absorbent. In addition, JNEP’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
JNEP 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.
The Performance of EADS
SO2 ≤ 35 mg/Nm3
Particulate content ≤ 5 mg/Nm3
Ammonia slip ≤ 3 mg/Nm3
Ammonia recovery ≥ 99%
No waste water or solid waste generation