Tubes Used for Spot Sampling in Metal Refineries 

The GASTEC gas detector tube system is a complete sampling and analysis system for determining hazardous gas and vapour concentrations quickly and easily. The pump is used with unique colorimetric tubes which display results almost immediately, with no need for further lab analysis.

Recently, a1-cbiss (UK) supplied a large amount of tubes to a large worldwide metal refinery company as part of a trial to encourage them to switch from Draeger tubes to GASTEC because of the ease of usage.

The GASTEC tubes allow accurate detection in less pump strokes than using the Draeger Accuro Pump.

The tubes used in the refinery process as a spot checking technique included:

Chlorine (GAS8LA) is a corrosive, pungent smelling, green/yellow gas. It is a very heavy gas and is readily absorbed by most materials. The behaviour of chlorine makes it a very difficult gas to detect yet GASTEC tubes make this possible.

Hydrogen Sulphide (GAS4H) is well known because of its bad egg odour, which can be smelt down to less than 0.1ppm. High concentrations over 150ppm cannot be smelt due to paralysis of the olfactory glands, and exposure over 1000ppm can lead to instant death. GASTEC tubes are used to spot check the correct levels of gas in the process.

Hydrogen Chloride (GAS14L) is a highly corrosive and toxic colourless gas that forms white fumes on contact with moisture. These fumes consist of hydrochloric acid which forms when hydrogen chloride dissolves in water. Inhalation of the fumes can cause coughing, choking, inflammation of the nose, throat, and upper respiratory tract, and in severe cases, death.

Nitric Oxide (GAS11L) is a colourless gas but nitrogen dioxide is an acid, pungent smelling, brown gas. Nitrogen Oxide that is produced is a bypass of the smelting process. At the point of exhaust, nitric oxide accounts for about 90% of NOx. However it reacts spontaneously with oxygen in the open atmosphere to produce nitrogen dioxide.

Mercaptans (GAS70) is added to natural gas (methane) to make it easier to detect in case of a leak: natural gas in its native state is colourless and odourless. Mercaptan contains sulphur, and has a strong odour similar to rotten cabbage or bad eggs. 

The low cost of the tubes and easy change out option make them the perfect solution for spot sampling in such a fast paced environment.

“We have recently decided to change from Draeger tube analysis to Gastec. The main drive for the change is the competitive price of the Gastec tubes and the next working day delivery as standard. In addition after a trial of the Gastec pump the user found it easier and quicker to use as most of the time the Gastec pump requires only one pull against 10 strokes on the draeger pump” Commented the Process Control Manager.