The Frothy Mechanism Of Glycol In Laya And Optimum Seeking Of Defoamer

The glycol system of Daqing Laerya Gas Station devices did not run steadily, it is found that theoutlet's resistance of two grade three phase segregator augmented and held back air pressure afterexamining and repairing the devices. Only when returning to primary temperature the system got right. Thesystem frothed severely by sampling and testing the glycol, The system could get its breath againtransitorily only by replacing the glycol system. As the glycol system did not run steadily, it brought somedifficulties to the device function. At the same time, getting back the primary temperature would reduce theoutput of light hydrocarbon, so it brought some loss of economy. So we must find out frothing reasons ofglycol system and took some measures to avoid the similar problem appearing again.In this experiment, we simulated natural gas refrigeration system of practical production. Taking aimat the serious frothing phenomena of glycol system of the shallow cooling devices in the Laerya GasStation of the Natural Gas Corporation, and the unsteady of the operation we put up specific experimentalstudy. We make use of advanced equipments, for example, AA670 type atom spectrophotometer, WK-2Dtype microcoulometry analyzer, D/MAX-ⅢA type X-ray diffraction analyzer, gas chromatography, SR-200interfacial tension apparatus, to detect and analysis various ionic content, sulfide, suspension with phasecomposition, viscosity, surface tension, etc., in the glycol medium. We evaluated the performance of glycolrefrigeration system, furthermore, discussed the frothing reason of the system, and we filtrated thedefoamer adapted to the refrigeration system. On the basis of above, we developed a sort of compositeorganic silicon emulsion defoamer XPJ. Through testing the performance of stability, dispersion nature,resistance of acid and alkali nature of the defoamer, on the basis of evaluating synthetically the ratiobetween dimethylsilicone oil and silicon dioxide, emulsifier combination, the order of adding the feed thatinfluence emulsion stability and defoaming ability, we obtained the proper components ratio of defoamer:20% dimethylsilicone oil, 2.5% silicon dioxide, 3.0% composite emulsifier with Speen-60 and Tween-60,3.0% liquid paraffin, 20% tributyl phosphate. The Hydrophile-Lipophile Balance of emulsifier is 8.9.Emulsifier dissolved in the oil phase, and aqueous phase was added to the oil phase, in this way, we canobtained the better defoamer. The defoaming velocity reached 28.4mm/s at -5℃, even at the lowertemperature, the defoaming velocity is also higher than 20mm/s. Futher study indicated that the defoamingtime of this composite defoamer XPJ is shorter in the alkalescence solution, the defoaming effect is better.All results show that this composite defoamer for gas refrigeration system has a better effect on defoamingand controlling foam.