In searching for lignocellulosic-based alternative pellets, quality is key, ash in particular, for market acceptance and penetration. One such feedstock of growing importance, pressed empty fruit bunches (EFB) fibres, was exploited in this study via 3 different physical pretreatment methods (Tests 1–3) prior to pre-pelletising in an industrial-scale plant for improving the ash content. The ash removal effects on quality of resultant pelletised EFB (in terms of fuel and physicochemical properties) were assessed and compared with commercial pellets based on available standards. The combined sieved and water sprayed feedstock (Test 3), 1.60 wt.% ash content (pre-pelletising), yielded EFB pellets with correspondingly better ash quality (1.58 wt.%, post-pelletising) than the sieved only (Test 2) option, 2.78 wt.% and 3.63 wt.%, and the untreated (control, Test 1), 4.07 wt.% and 4.66 wt.%, respectively. Besides, all the pretreated feedstocks/biopellets exhibited much improved proximate and ultimate properties, bulk density and calorific value (≤ 18 MJ kg⁻¹) after pre-pelletising/pelletising steps due to size reduction and drying. Both treatments (Tests 2–3) were able to produce lignocellulosic-based EFB pellets with fuel properties comparable to non-wood pellets, except for durability index (≤ 95%) and chlorine content (> 0.2 wt.%). In terms of wood pellets, Test 3 showed an advanced quality for ash compliance and reduction of unwanted ash-inducing elements, chlorine and potassium in particular, with > 40% removal efficiency. Henceforth, the combined sieving and spray water washing physical treatment of a high-ash lignocellulosic biomass offers an immediate low-hanging approach for practical utilisation and improvement of ash-related fuel properties of commercial solid biofuels.

在寻找基于木质纤维素的替代颗粒时，质量是关键，尤其是灰分，对于市场接受和渗透。在本研究中，通过 3 种不同的物理预处理方法（测试 1-3）在工业规模的工厂中进行预制粒以提高灰分含量，利用了一种日益重要的原料，即压榨空果串 (EFB) 纤维。评估了除灰对所得颗粒状 EFB 质量的影响（在燃料和物理化学性质方面），并根据可用标准与商业颗粒进行比较。结合筛分和喷水的原料（测试 3），灰分含量为 1.60 重量％（预制粒），产生的 EFB 颗粒的灰分质量（1.58 重量％，制粒后）比仅筛分的（测试 2）更好选项，2.78 wt.% 和 3.63 wt.%，和未处理的（对照，测试 1）分别为 4.07 重量％和 4.66 重量％。此外，所有预处理过的原料/生物颗粒都表现出大大改善的近似和最终性能、堆积密度和热值（≤ 18 MJ kg^-1 ) 由于尺寸减小和干燥，在预制粒/制粒步骤之后。除了耐久性指数（≤ 95%）和氯含量（> 0.2 wt.%）外，两种处理（测试 2-3）都能够生产出燃料特性与非木质颗粒相当的木质纤维素基 EFB 颗粒。在木屑颗粒方面，测试 3 显示出在灰分顺应性和减少不需要的灰分诱导元素（尤其是氯和钾）方面的先进质量，去除效率 > 40%。今后，高灰分木质纤维素生物质的组合筛分和喷水洗涤物理处理为商业固体生物燃料的灰分相关燃料特性的实际利用和改进提供了一种直接的低挂方法。