改質コーンコアパウダー及び汚泥系バイオ炭前処理における汚泥脱水における細胞外高分子物質の役割

Role of extracellular polymeric substances in sludge dewatering under modified corn-core powder and sludge-based biochar pretreatments.

• Zhiying Guo
• Liping Ma
• Quxiu Dai
• Ran Ao
• Hongpan Liu
• Yi Wei
• Liusen Mu

抄録

汚泥粒子に包まれた細胞外高分子物質(EPS)は、汚泥系における複合水の流出を阻害していると考えられている。汚泥の脱水性との関係を明らかにするためには、EPSの複雑な組成がネックとなっていた。本研究では、改良コーンコアパウダー(MCCP)とスラッジ系バイオ炭(SBB)を組み合わせた条件でスラッジ処理を行い、EPS中の有機物の濃度と形態分布、タンパク質二次構造の分散を調べた。汚泥の脱水性とEPS成分との相関を調べたところ、正味汚泥固形分収率(YN)とろ過比抵抗(SRF)に強い相関があることがわかった(R=-0.923),ゼータ電位(R=-0.971)。さらに、蛋白質の二次構造と脱水性能との関係が強く関連していた。SBBとMCCPの最適投与量では、凝集鎖とα-らせんが放出され、可溶性EPS(S-EPS)のアンフォールディングと脱スパイラル化が改善され、汚泥ネットワークが乱れ、結合水の流動抵抗が減少し、最終的に汚泥の脱水性が向上することが示された。

Extracellular polymeric substances (EPS) which wrapped on sludge particles were deemed to hinder the outflowing of combined water in sludge system. The complex composition of EPS was the bottleneck for revealing its relationship with sludge dewaterability. In this study, a combined modified corn-core powder (MCCP) and sludge-based biochar (SBB) condition was executed to treat sludge for enhancing dehydration performance, and the concentration and the form distribution of organics in EPS, the variances of protein secondary structures were investigated. Correlation between the sludge dewaterability and EPS components were performed, found strong correlations among the net sludge solids yield (YN) and the specific resistance of filtration (SRF) (R = -0.923), Zeta potential (R = -0.971). Furthermore, the relationship between the secondary structures of protein and dehydration performance were strong related. With the optimal dosage of SBB and MCCP, aggregated strands and α -helix were released, indicated that the unfolding and despiralization in soluble EPS (S-EPS) were improved, disordered the sludge network, reduced the flowing resistance of bound water, finally enhancing sludge dewaterability.

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