槽式太阳能热发电站中导热油的低温分步注油工艺流程介绍

INTRODUCTION TO PROCESS OF LOW-TEMPERATURE STEP-BY-STEP OIL INJECTION PROCESS OF HEAT TRANSFER OIL IN TROUGH CSP STATION

中国广核新能源控股有限公司投建并已投产的德令哈50 MW槽式太阳能热发电站是我国国内首座建设在高寒地区的大型槽式太阳能热发电站。该电站以导热油作为传热工质,但由于高寒地区的气温在绝大部分时间不能满足导热油的注入条件,且无相关的低温条件下注入导热油的经验,导致在此气候条件下注入导热油存在风险高、难度大的问题。针对在该热发电站中需注入的导热油量大、导热油系统复杂、管道多、管道直径细、导热油常温下凝结(凝结点为12℃)等特点,提出了一套成熟的低温分步注油工艺流程。该工艺流程将整个导热油系统注油分成多个小单元实行分批注入,并采取了提高初始注油温度、利用集热管集热、利用热空气对系统管道进行加热、通过排放阀排放管道端部的低温导热油等措施。通过实际验证,采用该低温分步注油工艺最终成功实现了在冬季时对德令哈50 MW槽式太阳能热发电站注入导热油。以期将该低温分步注油工艺流程广泛应用于国内西北地区及其他类似气候条件下的槽式太阳能热发电站的建设过程中。

The Delingha 50 MW trough CSP station was built by CGN New Energy Holdings Company Limited and had already put into production.It is the first large-scale trough CSP station built in the alpine region in China.This CSP station uses heat transfer oil as the heat transfer medium.The temperature in this region cannot meet the heat transfer oil injection conditions most of the time,and there is no relevant experience in injecting heat transfer oil under low temperature conditions,resulting in high risk and difficulty in injecting heat transfer oil under this climate condition.And in this CSP station,heat transfer oil to be injected is a great mount,the system is complex,the number of pipeline is large,the diameter of the pipe is small,and the freezing point of the heat transfer oil is low.Because of these factors,this paper proposes a mature low temperature step-by-step oil injection process.Batch injection,and adopted measures such as increasing the initial oil injection temperature,using the heat collecting tube to collect heat,heating the tube,and drain cold heat transfer oil through the drain valve.Through actual verification,the process finally successfully realized the injection of heat transfer oil for the Delingha 50 MW trough CSP station in winter.It is expected that the low-temperature step-by-step oil injection process will be widely used in the construction of trough CSP stations in the northwestern region of China and other similar climatic conditions.