Air Clean-Up


Chinese Power Plants Emit as Much NOX as All the Passenger Cars in the World


China has spent more on equipment to reduce NOx from power plants in the last two years than any other country, but it has a long way to go. The installed capacity of deNOx systems at the end of 2010


was 58,000 MW. This means that about 10 percent of the total coal-fired capacity of 600,000 MW is fitted with deNOx equipment. By contrast, two-thirds of the capacity is fitted with scrubbers to


remove acid gases such as SO2. McIlvaine Company forecasts the market for deNOx systems in World NOx Control Markets and tracks each individual Chinese air pollution control project in Chinese Utility Plans.


There are 200 power boilers at 100 plants in China which have installed Selective Catalytic Reduction systems (SCR). These power plants are mainly located in the population centers of Beijing, Guangdong, Zhejiang, Jiangsu, Shanghai, Fujian, Shanxi, etc. Only four power plants have installed the less efficient but cheaper Selective Non-Catalytic Reduction (SNCR) systems. All boilers installed since 2003 are equipped with Low NOx burners.


World NOx Emissions 200 million tons/yr 2010 Biogenic emissions


Anthropogenic emissions 85 115


The NOx emissions from Chinese coal-fired power plants were 9.5 million tons in 2010.


This compares to three million tons of emissions from U.S. power plants. Japan, South Korea, Taiwan and all of Europe


have higher percentages of NOx control on power plants than the U.S. has. The result is that the Chinese and U.S. coal- fired power plants together emit almost as much NOx as the coal plants in the rest of the


world combined. Man-made or anthropogenic emissions account for 57 percent of the total. Chinese power plants


emit 8.2 percent of the world’s anthropogenic NOx. Chinese power plants emit as much NOx as all the passenger cars in the world. India and other Asian countries are planning large numbers of new coal-fired power plants so the percentage contribution of China and the U.S. will shrink.


China has already demonstrated its willingness to spend large sums of money to clean up power


World Anthropogenic Emissions 115 million tons Chinese coal-fired power plants


Other coal-fired power plants U.S. coal-fired power plants Passenger cars Industry


Biomass combustion Other sources


plant emissions. Because there are so many existing power


plants without NOx control systems and because China continues to lead the world in construction


of new power plants, it will be the largest NOx control market over the next decade.


The market is served by a mix of Chinese and international companies. Initially all the technology came from outside of China. Now there are a number of experienced system vendors, including CPI Yuanda, Fujian Longjin, Beijing Guodian China Datang, Shanghai Electric and nine other significant suppliers.


There is rapidly growing catalyst manufacturing capability. It started with KWH of Germany transferring operations to Sichuan in 2004. A number of other facilities are now in operation. Cormetech of the U.S is partnering with China Chongqing Yuanda and operates a 10,000 M3


/yr


catalyst facility in Chongqing. A total of seven Chinese catalyst manufacturers are profiled in World NOx Control Markets.


Catalyst regeneration and replacement is presently very small market in China because most installations are less than five years old. However, in the longer term, China will offer the largest regeneration and replacement market. Through 2020 the U.S. will be the largest catalyst replacement and regeneration market. Since most international catalyst manufacturers are working at near capacity and the domestic capacity is raising, the potential for import of catalyst to China will diminish.


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Air Scrubber Technology Helps Cut Emissions from Tata Steel


Scrubber technology designed, manufactured and installed by ACWA AIR (UK), has helped Tata Steel achieve a 40% reduction in atmospheric emissions from one of its limestone kilns in Cumbria. Tata Steel operates four Maerz kilns at Shapfell, producing high grade lime for the iron and steel industries.


To control kiln emissions to specific levels set by the UK Environment Agency, each of the four kilns is installed with a wet scrubber, installed at the top of the plant, some 100 feet above ground level.


The four scrubbers have had their shells refurbished several times over their lifetimes, due to the abrasive nature of their operating environment - always ensuring that they achieved the required abatement levels. Recently, however, the scrubber on the No 4 kiln was in need of refurbishment and in line with Tata Steel’s pledge to minimise emissions on


all their production processes, the company asked ACWA AIR what could be done within the constraints of the existing system to reduce emission levels.


Following a site survey, ACWA AIR recommended that, concurrent with the shell refurbishment, the existing process should be modified to integrate its well proven venturi slot tray technology within the process. This would be more effective than the existing scrubbing technology and achieve much higher collection efficiencies.


Working within the constraints of the existing scrubber shell, ACWA AIR was able to engineer a venturi slot tray which provided lower emissions of dust, whilst making use of the existing scrubber vessel. The system integrated with the existing water and effluent pipe-work and gas seals and did not, in any way, impose any significant changes to the operation of the lime kilns.


Following commissioning of the modified scrubber, independent tests have proved that emissions from the No 4 lime kiln are consistently 40% less than previous values recorded before the refurbishments. Tata Steel Ltd also reported no adverse effects to the production process or kiln controls.


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