SPC Single Tower Integrated Desulfurization and Dedusting Depth Purification Technology (SPC-3D) is a proprietary technology developed independently by Beijing SPC Environment Protection Tech Co., Ltd. It provides desulfurization efficiency of above 99% and dedusting efficiency of above 90% within one absorber, meeting super clean emission requirements of 35mg/Nm3 for sulfur dioxide and 5mg/Nm3 for soot.
I. Technical principle
1. Efficient desulfurization and dedusting technology with rotational flow and sink flow coupling
Flue gas from the induced draft fan flows into absorber and through efficient rotational flow and sink flow coupling device to form a strong controllable turbulence space on hydrodynamic principle, where gas, liquid and solid phases are in full contact with each other, to improve mass transfer efficiency, with a liquid-gas ratio 30% lower than similar technologies. This is the first step of efficient desulfurization and dedusting.
2. Efficient energy-saving spray technology
This technology improves the structure of spray layer, changes nozzle arrangement, increase single layer slurry coverage to more than 300% and expands surface area required for chemical reaction, completing the second step of scrubbing. After 2 scrubbings through the efficient rotational flow and sink flow coupling device and energy efficient spray device for superimposed desulfurization efficiency, SO2 in the flue gas could be reduced to less than 35mg/Nm3.
3. Centrifugal bundle-type dedusting technology
After efficient desulfurization and preliminary dedusting, the flue gas goes through further efficient dedusting and demisting in the centrifugal bundle-type dedusting device to be stripped of micrometer-class dust and fine mist drops. This makes soot concentration lower than 5mg/Nm3.
II. Characteristics and advantages of SPC-3D technology
1. High desulfurization and dedusting efficiency
When SO2 concentration at absorber inlet is 1500-15000mg/Nm3, desulfurization efficiency is up to 99.8%; when soot concentration at absorber inlet is 30-50mg/Nm3, the soot concentration at the outlet is ≤5mg/Nm3 and fog drop content in purified flue gas ≤20mg/Nm3.
2. Short duration of reconstruction and small quantities of work
This technology can be applied to existing absorber without changing its external structure. Its application is simple and can be finished within 20-50 days.
3. Low investment and operation costs
This technology integrates desulfurization and dedusting by modifying absorber internals, requiring 30-50% less investment than conventional technology. Furthermore, the centrifugal bundle-type dust precipitator does not consume electricity and its resistance is comparable to demister.Its operation cost is 20-30% of the cost for conventional technology.
4. High stability and reliability of system operation
Highly adaptable to a wide range of flue gas pollutant contents and loads, the system runs stably and reliably and is easy to operate.
5. It can completely eliminate "gypsum rain".
6. It addresses the effect of insufficient space.
III. SPC-3D demonstration projects
1. Phase II #3 Unit (300MW) Improvement Project (Put into Operation in October 2014), Shanxi Datang International Yungang Thermal Power Co., Ltd.
2. FGD Reconstruction of #1 Coal-fired Unit (600MW) for Datang Tuoketuo Power Plant Phase I in Inner Mongolia (Put into Operation in December 2014)
IV. Expert review comments from technical review meeting on SPC Single Tower Integrated Desulfurization and Dedusting Depth Purification Technology
China Electricity Council held an expert review meeting on SPC Single Tower Integrated Desulfurization and Dedusting Depth Purification Technology (SPC-3D) in Beijing on December 20, 2014. This meeting was attended by representatives and experts from over 20 organizations such as the Resource Conservation and Environmental Protection Department under National Development and Reform Commission, Technology Standard Department under the Ministry of Environmental Protection, other relevant departments, related power generation groups and research institutes.
The SPC-3D technology is an innovation characterized by high efficiency using a single tower, low energy consumption, high adaptability, short construction period, no need for additional space and easy operation. It is suitable for deep purification of flue gas containing SO2 and soot.
The expert review panel agreed that this technology is innovative and advanced, offering a new, integrated solution to SO2 and soot purification for coal-fired power plants. Its application could be expanded to existing units for performance improvement and to new units for compliance with special emission limit and deep purification.