Coal fired power plants are constructing scrubbers to remove sulphur gases. Some of these scrubbers are as high as 20 storey hotel. Some of the fibre reinforced plastic (FRP) shells are over 100 ft in diameter.

In a typical system, lime slurry is pumped to the scrubber in pipes as big as 24 inches in diameter. The limestone slurry is sprayed through a 'Christmas tree' structure of piping and nozzles. The flue gases are discharged into FRP lined stacks which can be up to 400 ft high.

All of this requires many tons of FRP. Many areas also have special abrasion resistant coatings to prevent erosion by the slurry.

US power plants have been more reliant on high alloy stainless steels for many of these applications. But with the sharp rise in nickel there has been a switch to FRP. Asia has traditionally shown a preference for FRP because FRP is more readily available than exotic high nickel steels, which must be imported. FRP is a lower cost material but higher in application labour cost and the lower labour costs in Asia make the cost differential attractive.

This industry represents a big but volatile market for FRP. Individual scrubber projects can require millions of dollars ($) of FRP and regulatory deadlines result in uneven scheduling of projects. The result is that the market has peaks and valleys. These tend to be levelled out on a worldwide basis due to the different regulatory timing in each country. Orders were down last year so FRP suppliers will be recognising less FGD revenue next year (Table 1).

Replacement or new

The replacement market is rising rapidly. A number of systems in the USA and Europe are now 30 years old. Since there is a virtual moratorium on new plants in these areas it means that the life of existing plants must be extended.

The worldwide replacement market for FRP components is estimated at $200 million. Therefore the total market  in terms of revenue recognition is $691 million next year, down from $900 million this year.

The long term trend is positive. By 2020 the number of FGD systems will double over 2010.

At the end of 2020 there will be 1.7 million MW of FGD systems in operation (Table 2). In that year 74 000 MW of new FGD systems will go into operation and 1000 MW will be retired.

The revenues for FRP for new systems will remain relatively constant during the next 10 years. However the expenditures will be in Asia and not the Americas and Europe. China will be the leading FGD operator with over 40% of the total capacity.

FRP component replacement revenues will double to $400 million in 2020. This will include upgrades required by more stringent  regulations.

Composites

Successful application of FRP in FGD systems starts with the resins. Ashland and AOC are leading resin suppliers.

There are relatively few companies capable of field filament winding the very large structures needed for this application. Ershigs and Augusta Fiberglass are examples in this category.

Flake glass coatings are needed in the ductwork and scrubber inlet. The Ceilcote division of International Protective Coatings and ITW Futura Coatings are two of the suppliers active in this segment.

There are companies specialising in the scrubber piping. These include Reinforced Plastic Systems, Plasticon, Hanwei, and FGS SuZhou.

Much of the FRP will be purchased by scrubber system suppliers. In the past most of these suppliers have been companies based in Japan, the USA, Austria, Germany, and Italy. Now a number of Chinese companies are becoming leaders (Table 3).

Companies in this sector include Alstom, Babcock & Wilcox, Babcock Power, Mitsubishi, Hitachi, Marsulex, Fisia Babcock, Austrian Energy & Environment, and Chiyoda.  

To put this in perspective, the leading Chinese company now has 8% of all the FGD capacity contracted since 1966, when the first system was purchased in the USA. This experience has allowed some of these companies to begin competing in other Asian countries. This means that the market is truly international. 

Long-term market

Coal now supplies more than half the electricity generated in the world. Under any greenhouse gas reduction scenario coal will remain the main fuel for at least several decades. The harm from sulphur gases and particularly the small particles formed by sulphur dioxide (SO₂) reacting with ammonia and calcium in the atmosphere is well established. As a result, nearly all coal plants will eventually be fitted with scrubbers. FRP will continue to be an economic and high performance material for this application.

Materials selection

There will continue to be analysis and review of the materials selection. On 5-7 May in Shanghai the subject will be under review at the 14th Sulfur Dioxide, Nitrogen Oxide, Mercury and Fine Particle Pollution Control Technology & Management International Exchange Conference, held by the Chinese Society for Environmental Sciences (CSES).

McIlvaine continues to analyse the materials alternatives in Power Plant Air Quality Decisions.