Indian Institute of Technology Bhubaneswar, Odisha, 752050, India.
Indian Institute of Technology Bhubaneswar, Odisha, 752050, India.
J Environ Manage. 2021 Nov 1;297:113345. doi: 10.1016/j.jenvman.2021.113345. Epub 2021 Jul 27.
The applicability of waste to energy conversion technique is facing many issues because of current waste management practices. Focusing on the segregation issue of low-density polyethylene (LDPE) from food waste (FW), microwave (MW) co-pyrolysis of FW and LDPE was investigated in this study. Multifactor optimization of the operating parameters, viz., residence time, LDPE in feed and temperature, was done with response surface methodology to achieve maximum bio-oil yield with a low total acid number (TAN). Bio-oil yield and TAN varied from 17 to 42 wt% and 16-45 mg KOH/g respectively, in various experimental runs. The optimum conditions for maximum bio-oil yield with minimum TAN were residence time -7 s, LDPE in the feed-13% and temperature - 550 °C. A quadratic model was developed to predict bio-oil yield and TAN as a function of operating parameters with an error <8.1 %. Addition of LDPE improved the bio-oil yield (by 20 %). The bio-oil also exhibited reduction in moisture content and TAN (30% and 62 %) and increase in pH and higher heating value (HHV) (40 % and 44 %). Sugars (3.09 wt%), alkanes (1.64 wt%), acids (1.07 wt%), alcohols (0.85 wt%), phenols (0.59 wt%), furans (0.58 wt%) and ketones (0.55 wt%) were the major identified compounds in the bio-oil. Thus, the high HHV and chemical composition of bio-oil indicate its potential use in boilers, engines, turbines, transportation fuels and as a renewable feed for chemical synthesis. The main mechanism for bio-oil quality improvement was the synergetic effect of FW hydrocarbon and hydrocarbon radical (HC) and hydrogen radical (H) of LDPE. The energy consumption analysis showed an energy requirement of 13.11 kWh/kg for bio-oil production.
由于当前的废物管理实践，能源转换技术的适用性面临许多问题。本研究聚焦于从食物废物（FW）中分离低密度聚乙烯（LDPE）的问题，研究了 FW 和 LDPE 的微波（MW）共热解。采用响应面法对操作参数（停留时间、进料中的 LDPE 和温度）进行了多因素优化，以在低总酸值（TAN）下获得最大生物油产率。在不同的实验运行中，生物油产率和 TAN 分别在 17 到 42wt%和 16 到 45mg KOH/g 之间变化。最大生物油产率和最小 TAN 的最佳条件是停留时间-7s、进料中的 LDPE-13%和温度-550°C。建立了一个二次模型，以预测生物油产率和 TAN 作为操作参数的函数，误差<8.1%。添加 LDPE 可提高生物油产率（提高 20%）。生物油的水分含量和 TAN（分别降低 30%和 62%）以及 pH 和高位发热值（HHV）（分别增加 40%和 44%）也有所提高。在生物油中主要鉴定出的化合物有糖（3.09wt%）、烷烃（1.64wt%）、酸（1.07wt%）、醇（0.85wt%）、酚（0.59wt%）、呋喃（0.58wt%）和酮（0.55wt%）。因此，生物油的高热值和化学成分表明其在锅炉、发动机、涡轮机、运输燃料以及作为化学合成的可再生原料方面具有潜在用途。生物油质量提高的主要机制是 FW 烃和烃自由基（HC）与 LDPE 的氢自由基（H）的协同作用。能量消耗分析表明，生产生物油的能量需求为 13.11kWh/kg。
