EE - Forum Styles

Overcoming the Toxic Gas Threat in Pulp and Paper Plants

A wide variety of applications ranging from coke ovens to wastewater treatment facilities have the potential for toxic gas exposure. Toxic gas exposure – in this case, hydrogen sulfide (H2S) – can have minor to severe implications:

5 - 10 ppm: Relatively minor metabolic changes

100 ppm: Immediately Dangerous to Life and Health (IDLH)

100 - 1,000 ppm: Serious respiratory, central nervous, and cardiovascular system effect

1,000 - 2,000 ppm: Loss of consciousness and possible death

Obviously, toxic gas is a critical problem, not only threatening life, but also property since it’s equally flammable. One of the industries with a high potential for H2S release is pulp and paper manufacturing. Equipment associated with the kraft process where H2S can be a concern includes digesters, the recovery boiler, and steam / power production units. H2S is generated from the chemical processes to delignify wood material in batch or continuous digesters and H2S may become entrained in steam lines that run throughout the plant, threatening personnel and plant safety.

Like many industries, pulp and paper manufacturing is cost sensitive, which is why the advent of wireless toxic gas monitoring is so significant to these plants. Look at this comparison:

Wireless toxic gas monitoring with the Rosemount 928 puts protection against H2S within reach of every plant. In pulp and paper plants, wireless gas monitors should be installed near recovery boilers where “black liquor” is burned.

Monitoring for toxic gas is not only an issue of plant safety but also one of operational efficiency. A spike in H2S concentration is one indication that something has gone wrong with the process, plus aborted maintenance trips due to unreported gas leaks can be costly and time-consuming. Wireless toxic gas monitoring can be implemented at a fraction of the cost of conventional monitoring and provide far more flexibility – a win/win for the pulp and paper industry.