Growing stockpiles of waste oil sludge (WOS) are an outstanding problem worldwide. Self-sustaining Treatment for Active Remediation applied ex situ (STARx) is a treatment technology based on smoldering combustion. Pilot-scale experiments for the STARx Hottpad prove this new concept for the mobile treatment of WOS mixed intentionally with sand or contaminated soil. The experiments also allowed for the calibration and validation of a smoldering propagation numerical model. The model was used to systematically explore the sensitivity of Hottpad performance to system design, operational parameters, and environmental factors. Pilot-scale (~1.5 m width) simulations investigated sensitivity to injected air flux, WOS saturation, heterogeneity of intrinsic permeability, and heterogeneity of WOS saturation. Results reveal that Hottpad design is predicted to be successful for WOS treatment across a wide range of scenarios. The operator can control the rate of WOS destruction and extent of treatment by increasing the air flux injected into the bed. The potential for smoldering channeling to develop was demonstrated for the first time. Under certain conditions, such as WOS saturations of 80%, high heterogeneity of WOS saturations, or moderate to high heterogeneity of soil permeability, smoldering channeling was predicted to accelerate to the point that remedial performance was degraded. Field-scale simulations (~10 m width) predicted successful treatment, with WOS destruction rates an order of magnitude higher than the pilot-scale and treatment times increasing only linearly with bed height. This work is a key step toward the design and effective operation of field STARx Hottpad systems for eliminating WOS.

中文翻译：

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STARx Hottpad 用于废油污泥的阴燃处理：概念证明和关键设计参数的敏感性

不断增长的废油污泥（WOS）库存是世界范围内的一个突出问题。非原位主动修复自持处理 (STARx) 是一种基于阴燃的处理技术。STARx Hottpad 的中试规模实验证明了这种移动处理有意与沙子或受污染土壤混合的 WOS 的新概念。实验还允许校准和验证阴燃传播数值模型。该模型用于系统地探索 Hottpad 性能对系统设计、操作参数和环境因素的敏感性。中试规模（~1.5 m 宽）模拟研究了对注入空气通量、WOS 饱和度、固有渗透率的非均质性和 WOS 饱和度的非均质性的敏感性。结果表明，Hottpad 设计预计可在广泛的场景中成功用于 WOS 治疗。操作员可以通过增加注入床的空气流量来控制 WOS 破坏的速度和处理的程度。首次证明了阴燃通道发展的潜力。在某些条件下，例如 WOS 饱和度为 80%、WOS 饱和度的高度非均质性或土壤渗透性的中度至高度非均质性，预计阴燃窜流将加速到修复性能下降的程度。现场规模模拟（~10 m 宽）预测成功处理，WOS 破坏率比中试规模高一个数量级，处理时间仅随床高呈线性增加。