In our last blog post, we discussed the evolving mercury abatement market, use of powder activated carbon (PAC), designer sorbents and some of the challenges that activated carbon injection (ACI) presents to utilities and industrial boiler owners. Ideally, power producers need a system that allows them to inject any sorbent they want, at whatever rate they want, through a system convey routing that they choose. And of course, reliability is critical to the success of meeting MATS.
Since that last post, we’ve added a short primer on what mercury is, how it effects us, and methods of treatment. View that document under our Technical Information tab.
Eductor technology has long been a standard in ACI technology. However, an eductor system will not perform reliably if the system pressure exceeds 3 PSI. Higher injection rates, longer conveying distances, and the use of designer sorbents will dictate that an alternative be utilized.
A viable alternative to the eductor design incorporates the use of a zero clearance rotary airlock (RAL) to meter product into the dilute pressure conveying system. The zero clearance RAL greatly improves the feeding of PAC due to reduced leakage. This technology provides a slight increase in system pressure capability, up to 6 PSI. However, this design is not entirely reliable at the top end of its pressure range. Some RAL leakage will still occur and material abrasion (especially with some designer sorbents) can reduce the life of the RAL.
By listening to customer needs, Nol-Tec Systems has designed and innovated a convey system which is able to meet the need to convey higher rates, longer distances, and different sorbent types. This pressurized continuous transport system provides the capability to meter material at system pressures up to 12 PSI. Nol-Tec’s Gen 3 systems meet the mercury abatement challenges our customers are facing. For further information, visit our ACI web page.
How do we know we’re meeting our customers’ needs? Because in 2013, Nol-Tec invested a lot of time and effort in to field testing. Next post, we’ll discuss some of those test results.