کاهش آب مصرفی نیروگاه بخار با استفاده از برج خنک‌کن خشک اجباری با ریزش آب

نویسندگان

1 نیروگاه اسلام‌آباد، اصفهان

2 دانشگاه اصفهان

چکیده

مصرف زیاد آب در برج‌های خنک‌کن تر نیروگاه‌های بخار، از چالش‌های بزرگ در دنیاست. روش پیشنهادی برای کاهش مصرف آب این نیروگاه‌ها، استفاده از برج خنک‌کن خشک اجباری به‌جای برج تر است که تاکنون انجام نشده است. استفاده از این نوع برج‌های خنک‌کن علاوه بر کاهش راندمان نیروگاه، به شرایط جوی نیز وابسته است. یک روش برای حل این مشکل، ریزش آب روی برج در ساعت‌های اوج گرماست. در این مقاله این‌گونه از برج‌ها به‌صورت تحلیلی مطالعه شده و هر دو حالت خشک و تر آن بررسی شده‌اند. سپس برای یک نیروگاه بخار، اندازه و مشخصات برج‌های خنک‌کن خشک و تر در دمای طرح محاسبه شده‌اند. این نتایج با داده‌های تجربی و اطلاعات برج تر یک نیروگاه مقایسه شده و صحت آن مورد تأیید قرار گرفته است. فقط در دماهای محیط بیشتر از دمای طرح، از ریزش آب روی لوله و پره‌های برج خنک‌کن استفاده می‌شود. با استفاده از داده‌های هواشناسی، تعداد ساعاتی که دمای هوای محیط بیشتر از دمای طرح می‌باشد، محاسبه شده و میزان مصرف آب به دست آمده است. محاسبات نشان می‌دهند که برای واحدهای 320 مگاواتی نیروگاه اصفهان در دمای طرح °C30، حدود 97% در مصرف سالیانۀ آب صرفه‌جویی می‌شود. مقدار کاهش قدرت خروجی نیروگاه به‌دلیل مصرف الکتریکی فن و پمپ‌های برج خنک‌کن خشک 93/3% قدرت خروجی نیروگاه محاسبه شده است.

کلیدواژه‌ها


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