| Popis: |
Abstract A nonpolymeric gas hydrate inhibitor has been successfully field tested on a platform containing ten gas lift injection wells in an offshore location on Gulf of Paria near Trinidad. Several wells are connected to a common 2" pipeline with a typical pressure in the system of 1800-1900 psi. Gas decompression at the wellhead results in lowering the temperature below freezing and creates favorable conditions for hydrate formation. Prior to the test and in spite of using methanol, the field operator, Trinmar Ltd. experienced frequent flow disruptions due to gas hydrate formation. The inhibitor formulated in hydrocarbon solvent solution was injected into a gas line at initial concentration 1/2 of the previous methanol usage and the dosage concentration was gradually lowered to 1/15 of methanol until hydrate formation was observed. The hydrate disappeared upon inhibitor concentration increase to 1/10 of methanol. The treatment with the gas hydrate inhibitor was finally optimized at 1/8 of the former methanol usage. The entire field has been converted from methanol hydrates protection to the inhibitor following the successful test and the treatment has been running since late 1996 without any problems. No product accumulation in the system (gunking, agglomerating, etc.) has been observed. This is a result of the fact that the neat inhibitor is a liquid oligomer. Trinmar realized large direct and indirect monetary gains due to this new treatment. P. 711 |
