NEWS RELEASE DECEMBER 2014
Huge but Changing Power Plant Air Pollution Market in China Has $100 Billion Potential
China will spend $100 billion for air pollution control for power plants over the next decade. The question is where will that money be spent and for what equipment? The answer will be shaped by technology. This is an unprecedented opportunity for the development of better solutions with the assurance that there will be a high ROI for the winners.
Where: More stringent regulations have been set for power plants operating near cities. For example, some power plants will have to meet particulate limits of 5-10 mg/Nm3 vs. 30 mg nationwide. The location will also depend on the success of the effort to convert coal-to-gas and liquids. Under this program 800 million tons of coal per year will be converted to gas and piped from the western and northern coal fields to the large eastern cities. The cleaner burning gas will then be used for home heating and power. The investment in air pollution control for the conversion projects is going to be as big as the investment to clean up the coal burning power plants.
What: The equipment history for the Chinese power plant air pollution control industry starts with electrostatic precipitators. China has been the leading manufacturer of dry electrostatic precipitators for many years. Eighty-five percent of all the large coal-fired power plants in China are equipped with these devices. More than 800,000 MW of power plant precipitators are in operation in China.
Ten years ago China implemented regulations requiring SO2 removal from coal-fired power plants. There has also been a retrofit program. So now the majority of power plants have scrubbers. In the last five years there has been a program to reduce NOx through use of selective catalytic reduction (SCR). More than 25 percent of the power plants have SCR systems.
The latest regulations are shown below. However, more stringent regulations apply to some of the larger cities. Also there are already plans to reduce limits even lower.
No. |
Type of Facility and Fuel |
Pollutant |
Conditions |
Limits |
1 |
Coal-fired boilers |
Particulate |
All |
30 |
Sulfur Dioxide (SO2) |
New Boilers |
100
|
||
Existing Boilers |
200/400 |
|||
Nitrogen Oxides |
All |
100/200 |
||
Mercury |
All |
0.03 |
||
2 |
Oil-fired boilers or gas turbines |
Particulate |
All |
30 |
SO2 |
New boilers and gas turbines |
100 |
||
Existing boilers and gas turbines |
200 |
|||
NOx |
New oil-fired boilers |
100 |
||
Existing oil-fired boilers |
200 |
|||
Gas turbines |
120 |
It is safe to say that very low particulate, NOx, and SO2 limits will be applied over the coming decade. Many power plants will be retrofitted. There are choices to be made as to how to reduce each pollutant.
Particulate
- Improve the operation of the existing precipitator. There has been recent success with new components to meet the 30 mg/Nm3.
- Switch to a fabric filter and reduce to less than 10 mg/Nm3.
- Add a fabric section in the last stage of the precipitator to achieve 12 mg/Nm3.
- Add a wet electrostatic precipitator and achieve emissions below 10 mg/Nm3.
- Install a catalytic filter with DSI for emissions below 12 mg/Nm3.
On July 21, 2014, China Environmental Monitoring Station reported emissions for the No. 7 and No. 8 units of the Zhejiang Jiaxing power plant. The unit is equipped with an SCR, dry precipitator, scrubber and then a wet precipitator.
Pollutant |
Zhejiang emissions mg/Nm3 |
National limit mg/Nm3 (new units) |
Discrete particulate |
3.08 |
30 |
SO2 |
15.1 |
100 |
NOx |
23.67 |
100 |
The wet electrostatic option is a new one. It is possible to install it at the top of the scrubber, so this would be attractive for retrofits. On the other hand, a number of dry precipitators have been converted to fabric filters. This is also an attractive retrofit option.
NOx
There are several options for NOx reduction:
- Selective catalytic reduction (SCR) with plate or honeycomb catalysts located upstream of the air heater or downstream of the scrubber and a gas-to-gas heat exchanger
- SNCR
- Hybrid SNCR /SCR
- Catalytic filter
- Chemicals such as hydrogen peroxide
- Ozone in combination with a scrubber
For new plants, SCR will likely be the choice. However, any of the other technologies could be attractive for retrofits. The big attraction of the catalytic filter is the clean hot 850oF gas which can then be directed to an efficient heat exchanger. This can result in a low net carbon footprint for the plant.
SO2
Wet scrubbers using limestone as the reagent and gypsum as the end product are utilized in more than 80 percent of the existing Chinese power plants. But there are lots of options:
- Wet limestone gypsum
- Dry vessel type scrubber (spray drier or fluid bed)
- Dry sorbent injection
- Two stage system making hydrochloric acid in the first stage and gypsum in the second stage using lime rather than limestone
- Ammonia and other systems to produce fertilizers or sulfur products
China is on the cutting edge to extract the rare earths and metals from flyash. Option #4 would be a cost effective approach for the extraction. At this point it exists only as a recommendation from the McIlvaine Company. There is a significant potential for the catalytic filter/efficient heat exchanger to greatly reduce the net carbon foot print and reduce rather than add costs. So there is a very big incentive for international and Chinese companies to invest in research and development and become the leaders in this very large market.
For more information, click on:
N018 Electrostatic Precipitator World Market