DNC gases

Survey of DNC gases

MoRe Research has developed methods for measuring the flows and analyzing dilute non-condensable gases, DNCG*, or the sulfur content (TRS**) in the pulp mills' odorous gases. The concept is based on the fact that a portable gas chromatograph (GC) is set up on the site so that the weak gases from different test points can be quickly analyzed.

What is usually called dilute non-condensable gases, DNCG, or TRS gases contains a mixture of different sulfur-containing substances such as hydrogen sulphide, methylmercaptan, DMS and DMDS. The method for pulp mills to solve the problem with odorous gases to pull the different emissions together and collect them to a point, such as the soda boiler, for combustion. But in order to be able to dimension a plant for this, the size of the flows and their composition must be known and mapped.

According to EU directive 2010/75/EU, the requirements of the BAT conclusions must be met by 30 September 2018 and all pulp mills must show how the requirements are followed or how they plan to follow them.

Since there is a wider deadline when new emission conditions apply to sulfur, we see here a need that we solve for our customers. Although the use has environmental permits that go beyond the time limit set by the EU, the sulfur condition will be renegotiated and, in many ways, the need may be to have the flows measured and analyzed.

Eurocon collaborates with MoRe in designing systems for collecting and destroying TRS gases, according to EU directive 2010/75/EU on BAT. More info.

*)Diluted non-condensable odorous gases: TRS-containing gases which are not strong odorous gases (e.g. gases coming from tanks, washing filters, chip bins, lime mud filters, drying machines).

**)Total reduced sulphur: The sum of the following reduced malodorous sulphur compounds generated in the pulping process: hydrogen sulphide, methyl mercaptan, dimethylsulphide and dimethyldisulphide, expressed as sulphur.

Contact: Michael Sjögren, +4670 572 87 20, E-mail