LIUBo,ZHANGZi-geng,YUANHong-lin,et al.Floating Transportation Performance of Sodium Alginate-based Food Waste Microcapsule in Sewage Pipes[J].China Water & Wastewater,2025,41(19):66-73.
Floating Transportation Performance of Sodium Alginate-based Food Waste Microcapsule in Sewage Pipes
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第41卷
Number:
第19期
Page:
66-73
Column:
Date of publication:
2025-10-01
- Keywords:
- food waste; sodium alginate; microcapsule; sewer pipe; carbon emissions
- Abstract:
- Transferring food waste (FW) from the solid waste stream to the wastewater stream represents a promising integrated management strategy within the context of dual carbon objectives. However, the process of pulverizing FW and discharging it directly into the sewer system may substantially intensify unregulated greenhouse gas (GHG) emissions originating from the sewer network. To address this issue, the rapid gelation reaction between sodium alginate (SA) and Ca2+ was utilized to fabricate microcapsules. Additionally, hydroxypropyl methylcellulose (HPMC) was incorporated as a foaming agent to enable the floating transportation of FW. By optimizing the preparation process of microcapsules and investigating their comprehensive properties under simulated pipeline water flow conditions, the resulting microcapsules exhibited a high embedding rate, high drug loading capacity, and low density. Additionally, they demonstrated excellent solubility inhibition and floating performance in the simulated pipeline environment. The morphology and elemental composition of the microcapsules were characterized using field emission scanning electron microscopy (SEM), confirming their ability to effectively encapsulate FW. The carbon emission calculation results indicated that microencapsulation reduced the carbon emissions of urban sewer network by 75.60% and 72.58% when the hydraulic retention time (HRT) was set to 3 hours and 6 hours, respectively, compared with pulverized direct discharge. This approach offers a novel strategy for achieving carbon neutrality in urban sewer system.
Last Update:
2025-10-01