Halting harmful flue gases - Part 1

This is part one of a two-part article written by Viv Williamson, FPE Global, for World Cement’s BMHR supplement issue. Subscribers can read more high-quality articles by signing in, and can also catch upon-the-go via our new app for Apple and Android.

Flue gas from cement plants, coal fired power stations, biomass plants and energy from waste plants generally contains acidic gases such as hydrogen chloride, sulfur dioxide and hydrogen fluoride, making it a high cause of pollution.

The Industrial Emissions Directive (2010/75/EU) covers the control of such emissions and sets stringent limits for a number of potential pollutants. To effectively manage a facility’s environmental impact, it is important to be aware of exactly what it is.

FPE Global’s established a number of innovative solutions to control this issue, proven to reduce over 90% of harmful flue gas emissions. One method is injecting a bulk powder such as hydrated lime or sodium bicarbonate straight into the exhaust ducting at the optimum point. Generally, over 99% of the HCl, over 95% of the HF and over 95% of SO² can be removed. In addition, bulk powders such as powder activated carbon and urea prill are also used to treat unwanted gases such as mercury, NOx and SOx.

In response to this environmental requirement FPE Global has developed a number of dosing and pneumatic injection systems, designed to allow the automatic introduction of powders into the emission exhaust ducting. In 2010 the company launched a pioneering mobile dosing rig, which has successfully been installed at several blue chip companies across the world.

The unique benefit of this product is its modular plug and play design, which allows it to be easily installed into an existing plant using a fork lift truck. Once in position, it is only a matter of connecting to the compressed air and 3 phase power supply. The Modular Dosing Rig accepts 1000 kg FIBC big bags, normally loaded via a fork lift or hoist. This is the only manual intervention required until the bag becomes empty. The dosing rig is fully automatic; it transfers powder via a flexible or rigid conveying line under positive pressure into a flue gas duct.

The system is usually controlled by an emissions gas monitor mounted in the duct, which regulates the quantity of powder required, thus minimising waste product.

A loss-in-weight loads cell system monitors the discharge rate of powder, which is ultimately dosed via an inverter controlled screw feeder that regulates the speed and delivers the powder into the conveying line.

FPE’s Dosing Rigs can be designed to provide a consistent conveying rate of between 10 – 2000 kg/hr.

The pneumatic transfer system can be designed to convey the powder over a distance of up to 150 m.

Edited for web by Joseph Green

Read the article online at: https://www.worldcement.com/special-reports/14082015/halting-harmful-flue-gases-1/