The most common location for foaming in an amine system is in gas treaters or absorbers. Foaming in amine absorbers can result in reduced treating capacity, off specification products and high amine losses. If the problem is condensing hydrocarbons, the foaming may be resolved by increasing the Lean Amine temperature. If hydrocarbons are entrained in the gas feed, increasing the temperature may have little or no effect.

The injection of DEFOMAMINE 700  into the Lean Amine feed to the absorber(s) should resolve the foaming. It can be injected with “shot feed” injection equipment or with a chemical injection pump. For shot feed applications, two to four quarts are injected at a time. The dosage for a continuous injection system is typically 10 to 50 ppm (mg/L)/day based on system volume.
The use of DEFOMAMINE 700  has also been beneficial in improving the separation of gas, liquid hydrocarbon and amine solution when injected into the Rich Amine upstream to the Flash Drum. One of the most serious locations for foaming is in the regenerator. Foaming in the regenerator usually corresponds with a loss of liquid level in the bottom of the tower, reduced tower top temperature and a higher Lean Amine loading. Reducing the steam rate may allow the hydrocarbon to descend in the tower, reducing the foaming by reducing vapor traffic. Alternately, a small amount of DEFOMAMINE 700  injected into the Rich Amine or Reflux can help resolve the problem. Hydrocarbons that vaporize overhead should be removed by purging the reflux accumulator to the waste water system.
 

As with any foaming control chemical, the presence of other antifoams may have a negative side effect on performance. Whenever possible, allow several hours or even days for one antifoam product to exit nthe system prior to injecting a new product. DEFOMAMINE 700 has been found to be compatible with most polyglycol and alcohol type of antifoams but high concentrations of silicone based products reduce its performance.