老舊燃氣立管問題分析及改造管材選型研究

〔摘 要〕隨著我國城市燃氣設施逐步進入老化周期，早期建設的燃氣立管因管材腐蝕、老化導致的泄漏問題日益嚴重，不僅威脅公共安全，還加劇了甲烷排放引發的環境問題。針對鍍鋅鋼管與鋁塑復合管在戶外應用中存在的工藝缺陷、防腐不足、維護困難等問題，提出涂覆碳鋼管與戶外用聚乙烯耐候管兩種改造方案。通過材料特性、施工工藝、經濟性及實際應用案例的對比分析，發現戶外用聚乙烯耐候管初始投資的戶均成本略高，但使用壽命長且具有免維護的特性，在全壽命周期經濟性上更具競爭力，可作為老舊燃氣立管改造的首選材料。

〔關鍵詞〕老舊燃氣立管；管材選型；甲烷減排；涂覆碳鋼管；聚乙烯耐候管

中圖分類號：TU996.9 " 文獻標志碼：B" 文章編號：1004-4345（202５）0１-0057-05

Analysis of the Problems of Old Gas Risers and Research on the Selection of Retrofitting Pipe Materials

LAN Yexiang1， GUO Yan2

（1. Jiangxi Provincial Investment Gas Co.， Ltd.， Nanchang， Jiangxi" 330096， China;

2. Jiangxi University of Technology， Nanchang， Jiangxi" 330098， China）

Abstract As China’s city gas facilities gradually enter the aging cycle， the leakage of gas risers constructed in the early days due to corrosion and aging of pipes is becoming more and more serious， which not only threatens the public safety， but also aggravates the environmental problems caused by methane emission. Aiming at the process defects， insufficient anti-corrosion and maintenance difficulties of galvanized steel pipe and aluminum-plastic composite pipe in outdoor applications， two transformation schemes of coated carbon steel pipe and outdoor polyethylene weathering pipe are proposed. Through the comparative analysis of material characteristics， construction process， economy and actual application cases， it is found that the average household cost of the outdoor polyethylene weathering pipe is slightly higher than the initial investment， but it has a long service life and is maintenance-free， which makes it more competitive in terms of whole-life cycle economy， and it can be used as the preferred material for the renovation of old gas risers.

Keywords" old gas risers; pipe selection; methane emission reduction; coated carbon steel pipe; polyethylene weathering pipe

截至2023年年底，被稱為城市“生命線”的全國城市和縣城燃氣管道總長度約達121.9萬km。自二十世紀八九十年代起，我國從煤制氣時代邁入天然氣快速發展時期。在這個過程中，很多早期建設的燃氣管網設施已使用長達二三十年，進入了老化周期。當時建設的燃氣管網設施受設備、管材、防腐技術、規劃條件、設計規范、技術能力等因素制約，存在建設標準低、施工質量較差等問題。在實際運行中，燃氣企業未能及時落實日常維護、保養及更新等安全主體責任。相應的監管力量及監管執法能力水平也未與之匹配，存在執法“寬、松、軟”現象。多重因素疊加造成燃氣管道腐蝕泄漏，進而加劇了溫室效應并頻發安全事故。……