Abstract Cellulose fiber (CF) is a cost-effective and eco-friendly thermal insulation material which has largely found its application in the construction industry to provide wall insulation in residential and commercial buildings. Biogas digesters too are constructed with walls which should be insulated to limit digester temperature fluctuations which are unfavorable for methane formation. The objective of this study therefore was to evaluate the effectiveness of CF as a thermal insulation material for biogas digesters. Design, development and testing strategies were thus adopted to determine the percentage heat loss reduction on a cylindrical biogas digester insulated with locally made cellulose fiber material. Pilot study results indicate that over 82% of heat loss reduction was achieved with cellulose fiber density of 44.4 kg/m3 on horizontal application, and 62.7 kg/m3 on vertical application with external digester heating from a solar thermal siphon-heat exchanger configuration. This was only 2% less that the analytical frame of 84% with an optimum insulation thickness of 9 cm. CF is thus an effective insulation material for bio-digesters, but must be protected from hazard as might be caused by vermin and moisture penetration. This can be made possible by enclosing the insulation with a rigid protective envelop, which also supports its loose-fill installation.

中文翻译：

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纤维素纤维作为生产沼气系统隔热材料有效性的性能评估

摘要 纤维素纤维 (CF) 是一种具有成本效益和环保的隔热材料，已广泛应用于建筑行业，为住宅和商业建筑提供墙体保温。沼气池的壁也应隔热，以限制不利于甲烷形成的消化池温度波动。因此，本研究的目的是评估 CF 作为沼气池隔热材料的有效性。因此，采用设计、开发和测试策略来确定用本地制造的纤维素纤维材料隔热的圆柱形沼气池的热损失减少百分比。试点研究结果表明，当纤维素纤维密度为 44 时，热量损失减少了 82% 以上。水平应用时为 4 kg/m3，垂直应用时为 62.7 kg/m3，使用太阳能热虹吸热交换器配置的外部消化器加热。这仅比 84% 的分析框架少 2%，最佳绝缘厚度为 9 cm。因此，CF 是一种有效的生物消化器绝缘材料，但必须防止可能由害虫和湿气渗透引起的危险。这可以通过用刚性保护套封闭绝缘体来实现，这也支持其松散填充安装。但必须防止可能由害虫和湿气渗透引起的危险。这可以通过用刚性保护套封闭绝缘体来实现，这也支持其松散填充安装。但必须防止可能由害虫和湿气渗透引起的危险。这可以通过用刚性保护套封闭绝缘体来实现，这也支持其松散填充安装。