摘要 |
The interior surface of a pipeline is dried by sequentially passing through the pipeline (a) an aqueous cross-linked gelled pig, (b) a fluid mobility buffer comprising a non-crosslinked gelled ankanol of from one to three carbon atoms, (c) a dessicating amount of a liquid alkanol from one to three carbon atoms. For example, a pipeline was dried by sequentially passing through it (a) a borate cross-linked hydroxypropyl guar gum pig, (b) a fluid mobility buffer comprising methanol thickened with hydroxypropyl cellulose, and (c) methanol.
|