H2S Scavenger Blend Capacity

The following Calculator can be used to determine the uptake capacity of a certain H2S Scavenger blend. The most common liquid scavengers utilized in the Oil and Gas industry are Triazines and/or variations of them. Most are derived from the reaction of formaldehyde and an alcohol. Numerous chemical suppliers have made “novel” blends to compete with the traditional Triazine offerings. These are however still derived (in most cases) from Formaldehyde and alcohols.

The calculator allows you to determine how much scavenger (of a certain blend) is required to remove a kg of H2S. The result would be a theoretical value assuming 100% efficiency. The value will have to be adjusted to reflect the actual efficiency expected in the field, which is broadly determined by the application method pursued. How do you use the calculator? It is relatively straight forward, you simply select the active components in your scavenger blend form the dropdown menus. The calculator allows for three different components. It should be emphasized again that only active materials should be selected, this refers to the chemistry that will react with the H2S. Any solvents like water or Methanol should not be included. For example, you have a MEA Triazine blend that is 40% active, the other 60% is water.

You will now simply select Component 1 as MEA Triazine and enter 40% as the wt%. Component B and C can be left blank or just add 0% to those. The calculator will automatically assume the difference (60%) is made up of non reacting solvents, which does not affect uptake capacity. Click the calculate button, which should then return a calculated uptake capacity, in this case it should return 8.075 kg per kg H2S. This means that you need at least 8.075 kg of your blend to remove 1 kg of H2S. As mentioned before, the calculated value will have to be adjusted to reflect achievable efficiency. General rule of thumbs, use an efficiency of 50% for direct injection applications and 80% for properly designed Contactor vessels (Bubble columns). You simply take the calculated value and divide it by 0.5 for direct injection and in the case of bubble towers by 0.8. Thus you would require ~ 16.15 kg of product per kg of H2S removed when applying your product via direct injection and ~ 10.09 kg product per kg H2S removed in Contactor vessels (Bubble Columns).

Feel free to use the calculator below to convert the capacity to kg of product per e3m3 gas/ ppm H2S. (kg product/e3m3/ppm)

Canada commonly uses the above format to calculate scavenger treatment rates. For example, you use the capacity calculator and determined your blend has a capacity of 10kg /kg H2S removed. You enter that into the calculator above and it shows a treatment rate of 0.01508 kg/e3m3/ppmv H2S. As an example, gas production is 100 e3m3/day and H2S concentration is 100 ppm(v). Treatment rate is thus 0.01508*100*100 = 150.8 kg/day. Now simply divide by the product density to get to Liters/day.