Characteristics of Ammonia Desulphurization

Ammonia desulphrization is a high-effective and low energy-consuming wet process, which has a boundful raw materials. Its biggest characteristics is to produce by-products of high additional value by utilizing exhausted gas SO2. The by-product ammonium sulfate can be applied as a good fertilizer, having a prospective market in China.

Jiangnan Ammonium Desulphurization

Jiangnan ammonium desulphurization is one kind of wet ammonium desulphurization, which has 7 advantages totally listed as below:

• Recycling use of the exhausted gas and ammonia sewage
• High-value by-product (ammonium sulfate) and low running cost
• Lower installing requirements on device resistance
• Advanced anti-corrosion technology from abroad and materials/devices of high reliability
• No pretreament on raw materials and simple by-product producing progress. Small devices, apt to old boiler's transformation
• Desulphurization & DeNOx
• Intellectual patents

Jiangsu Century Jiangnan Environmental Protection (JCJEP) Company holds 14 patents on ammonia-fertilizer flue gas desulphurization, and is awarded the sole right to operate, transfer, apply the 11 patents on ammonia FGD and the National "863" Project ammonia-fertilizer technology, invented by East China University of Science and Technolony. This technology has total 25 patents on invention & practical use, almost covers every key aspect of ammonia desulphurization.

Desulphurization & By-product Formation Process
Desulphurizing process causes ammonium sulfate, the so-called " fertilizing powder", which is widely applied as nitrogenous fertilizer or being mixed with other fertilizes. It has the following advantages comparing with other nitrogenous fertilizers:

• High utilization ratio of nitrogen
• Low absorption of humidity and good physical property
• Stable chemistry, uneasy to decompose
• Excellent performance to be mixed with most nitrogenous, phosphate, potash fertilizers.

On basis of national statistics, the ammonium sulfate quantity used for compound fertilizer amounts to 1,500,000 tons per year. Apart from this, the export quantity exceeds 2,000,000 tons per year. However, our current output for ammonia sulfate is appoximately 1,500,000 tons per year. That is to say, the by-product---ammonium sulfate has a tremendous market demand and numerous profit.

Process Flow Diagramm

• The Flue Gas delivered by booster jar enters into the desulphurization tower, absorbs the SO2, and is abated out of chimney after being heated at 70℃ or abated directly.
• During the absorbing process, ammonium sulfit is generated and then oxidized and crystallized into ammonium sulfate,

System Components

The FGD system mainly includes Absorber, Booster, Flue Gas Reheater, Circulating Pump, Circulating Cannelure, Oxidation Fans, Absorbent gouge, Crystallizer, Filter, Segragator, Drier, and Packing Machine.

Anti-errosion Technology

• Jiangnan's FGD system is designed to be used for 30 years, keeping in the same level with boilers' lifespan.
• Anti-errosion of devices: with flake resin powder technology, desulphurization tower and flue are provented from errosion of SO2, HCL, HF.       

Quality index of By-product Ammonium Sulfate
Excuting Criteria: GB535-1995   D/LT808-2002
Sample appearance: no visible impurity; white/gray-white particle or powder
N (%) ≥21.0≥18.0 21.09
H₂o(%) ≤0.3≤1.5 0.09
H₂SO₄(%) ≤0.05≤2.0 0.039
Remarks: This index subjects to the testing data on real samples extracted from FGD project spot
                   by Jiangnan Environmental Protection.
Conclusion: Our by-products meet and exceed the criteria established by the country and industry.