ظرفیت گرمای ویژه و ضریب هدایت حرارتی کود ورمی کمپوست

نوع مقاله: مقاله پژوهشی

نویسندگان

1 دانشگاه محقق اردبیلی

2 دانشگاه تهرن- پردیس ابوریحان

3 دانشگاه تهران-پردیس ابوریحان

چکیده

یکی از بهترین روش­های بازیافت، تولید ورمی­کمپوست از زباله شهری است. جداسازی بهینه کرم­ها از مواد آلی بعد از اتمام فرآیند ورمی کمپوست­سازی باعث افزایش نرخ تجزیه مواد زائد توسط کرم­ها می­شود. جهت طراحی و ساخت دستگاهی برای القاء حرارت به بستر کود ورمی کمپوست به صورت کنترل شده که هم باعث جداسازی کرم­ها از بستر شده و هم آسیبی به کرم وارد نشود، داشتن پارامترهای حرارتی کود ورمی کمپوست ضروری می­باشد. در این تحقیق ظرفیت گرمای ویژه و ضریب هدایت حرارتی به ترتیب با روش اختلاط و روش سیم داغ به دست آمد. آزمایشات با سطوح محتوای رطوبتی 10، 20، 30، 40 و 50%(w.b) در دماهای 40، 50، 60 و C°70 انجام گرفت. مقدار ظرفیت گرمای ویژه از 6537/1 تا kj/kg°C 5236/3 با افزایش دما و رطوبت افزایش یافت. مقدار ضریب هدایت حرارتی بین 1054/0 تا Wm-1°C-1 9163/0 با افزایش دما و رطوبت به صورت خطی افزایش یافت.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Specific Heat and Thermal Conductivity of vermicompost

نویسندگان [English]

  • Seyed Amir Zaki 1
  • Ezzatollah Askari Asli ardeh 1
  • Mohammad Hosein Kianmehr 2
  • Javad Khazaei 3
1 Mohaghegh Ardebili University
2 Abureyhan Campus
3 Abureyhan Campus
چکیده [English]

One of the best ways for recycling is the Producing of vermicompost from municipal waste. Worms optimal separation of organic material after finishing process increases the rate of decomposition of waste by composting worms placed.To design and build a system for induction heating the substrate in a controlled vermicompost fertilizer which leads to separation worms from bed and does not get hurt, the thermal parameters manure vermicompost is the essential. The method of mixtures and hot wire as a heating source was used for measuring the specific heat and thermal conductivity of vermicompost, respectively. The measurements were done at 40, 50, 60 and 70ºC temperature levels and 20, 30, 40 and 50% (w.b) moisture content levels. The specific heat of vermicompost increased from 1.6537 to 3.5236 kj/kg°C, with increase in the experimental temperature and moisture content levels. The thermal conductivity of vermicompost increased from 0.1054 to 0.9163 wm-1°C, with increase the temperature and moisture content.

کلیدواژه‌ها [English]

  • Hot wire method
  • Method of mixtures
  • Moisture content
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