Effects of coagulation/flocculation followed by dissolved air flotation on anaerobic digestion of coffee processing wastewater

IF 3.5 4区工程技术 Q3 ENERGY & FUELS

Biomass Conversion and Biorefinery Pub Date : 2024-09-30 DOI:10.1007/s13399-024-06167-z

Raphael Rivadávia, André Pereira Rosa, Larissa Almeida Nascimento, Dilson Novais Rocha, Fabiana Lopes Del Rei Passos, Natália dos Santos Renato, Alisson Carraro Borges

{"title":"Effects of coagulation/flocculation followed by dissolved air flotation on anaerobic digestion of coffee processing wastewater","authors":"Raphael Rivadávia, André Pereira Rosa, Larissa Almeida Nascimento, Dilson Novais Rocha, Fabiana Lopes Del Rei Passos, Natália dos Santos Renato, Alisson Carraro Borges","doi":"10.1007/s13399-024-06167-z","DOIUrl":null,"url":null,"abstract":"<div><p>This study aimed to optimize the conditions of chemically assisted physical treatment (CAPT) using coagulation/flocculation followed by dissolved air flotation (C/F + DAF) for solid removal, assess the impact of primary treatment on anaerobic digestion using a biochemical methane potential (BMP) test, and evaluate kinetic models’ fit to biogas production results for coffee processing wastewater (CPW). In Phase 1, CPW underwent characterization, and C/F + DAF conditions were optimized using ferric chloride in a rotational central composite design. pH and coagulant were independent variables, while removed turbidity and residual phenolic compounds (PC) were response variables. PC, associated with coffee fruits, can inhibit microbial activity, affecting anaerobic digestion efficiency. Phase 2 evaluated the primary treatment’s impact on anaerobic digestion via biomethane potential tests (BMP). CPW exhibited an acidic pH of 4.20 and high organic matter levels, with a total organic carbon (TOC) concentration of 2950 mg L<sup>−1</sup>. Additionally, it contained phenolic compounds (PC) at 87.2 mg L<sup>−1</sup> and turbidity of 592.7 NTU, indicating a significant pollution load. In the CAPT optimization, turbidity removal ranged from 4 to 90% NTU, and PC removal ranged from 2.4 to 61% mg L<sup>−1</sup> as C<sub>76</sub>H<sub>52</sub>O<sub>46</sub> in the optimization experiment. Substantial reductions in organic load (35%), turbidity (68.23%), and PC (21.11% reduction) were observed after DAF in the absence of a coagulant. Untreated CPW (CPW<sub>u</sub>) and CPW treated with dissolved air flotation (CPW<sub>f</sub>) underwent a BMP test. The accumulated methane production was 379.1 mL ± 4.67 g VS<sup>⁻1</sup> for CPW<sub>u</sub> and 388.6 mL ± 5.23 g VS<sup>-</sup><sup>1</sup> for CPW<sub>f</sub>. The first-order kinetic model described methane production best, with rate constant (<i>k</i>) values of 0.51 and 0.48 d<sup>−1</sup> for CPW<sub>u</sub> and CPW<sub>f</sub>, respectively. DAF effectively removed turbidity and PC without hampering biogas production. The results of this research add to sustainable wastewater management in the coffee industry and have implications for biogas and energy recovery, underlining the potential for generating renewable energy through anaerobic digestion.</p><h3>Graphical Abstract</h3>\n<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":488,"journal":{"name":"Biomass Conversion and Biorefinery","volume":"15 8","pages":"11645 - 11658"},"PeriodicalIF":3.5000,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Biomass Conversion and Biorefinery","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s13399-024-06167-z","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ENERGY & FUELS","Score":null,"Total":0}

引用次数: 0

Abstract

This study aimed to optimize the conditions of chemically assisted physical treatment (CAPT) using coagulation/flocculation followed by dissolved air flotation (C/F + DAF) for solid removal, assess the impact of primary treatment on anaerobic digestion using a biochemical methane potential (BMP) test, and evaluate kinetic models’ fit to biogas production results for coffee processing wastewater (CPW). In Phase 1, CPW underwent characterization, and C/F + DAF conditions were optimized using ferric chloride in a rotational central composite design. pH and coagulant were independent variables, while removed turbidity and residual phenolic compounds (PC) were response variables. PC, associated with coffee fruits, can inhibit microbial activity, affecting anaerobic digestion efficiency. Phase 2 evaluated the primary treatment’s impact on anaerobic digestion via biomethane potential tests (BMP). CPW exhibited an acidic pH of 4.20 and high organic matter levels, with a total organic carbon (TOC) concentration of 2950 mg L⁻¹. Additionally, it contained phenolic compounds (PC) at 87.2 mg L⁻¹ and turbidity of 592.7 NTU, indicating a significant pollution load. In the CAPT optimization, turbidity removal ranged from 4 to 90% NTU, and PC removal ranged from 2.4 to 61% mg L⁻¹ as C₇₆H₅₂O₄₆ in the optimization experiment. Substantial reductions in organic load (35%), turbidity (68.23%), and PC (21.11% reduction) were observed after DAF in the absence of a coagulant. Untreated CPW (CPW_u) and CPW treated with dissolved air flotation (CPW_f) underwent a BMP test. The accumulated methane production was 379.1 mL ± 4.67 g VS^⁻1 for CPW_u and 388.6 mL ± 5.23 g VS^-¹ for CPW_f. The first-order kinetic model described methane production best, with rate constant (k) values of 0.51 and 0.48 d⁻¹ for CPW_u and CPW_f, respectively. DAF effectively removed turbidity and PC without hampering biogas production. The results of this research add to sustainable wastewater management in the coffee industry and have implications for biogas and energy recovery, underlining the potential for generating renewable energy through anaerobic digestion.

Graphical Abstract

查看原文本刊更多论文

混凝/絮凝+溶气浮选对咖啡加工废水厌氧消化的影响

本研究旨在优化混凝/絮凝+溶气浮选（C/F + DAF）去除固体的化学辅助物理处理（CAPT）条件，通过生化甲烷势（BMP）测试评估初级处理对厌氧消化的影响，并评估动力学模型与咖啡加工废水（CPW）产气结果的拟合性。在第一阶段，CPW进行了表征，并在旋转中心复合材料设计中使用氯化铁对C/F + DAF条件进行了优化。pH和混凝剂为自变量，去浊度和残余酚类化合物（PC）为响应变量。咖啡果实中含有的PC，能抑制微生物活性，影响厌氧消化效率。第二阶段通过生物甲烷潜力测试（BMP）评估了初级处理对厌氧消化的影响。CPW的酸性pH值为4.20，有机质含量较高，总有机碳（TOC）浓度为2950 mg L−1。此外，它含有酚类化合物（PC）为87.2 mg L−1，浊度为592.7 NTU，表明污染负荷很大。在优化实验中，C76H52O46的浊度去除率为4 ~ 90% NTU， PC去除率为2.4 ~ 61% mg L−1。在没有混凝剂的情况下，DAF后有机负荷（35%）、浊度（68.23%）和PC（21.11%）显著降低。未处理的CPW （CPWu）和溶气浮选处理的CPW （CPWf）进行BMP试验。CPWu的累积甲烷产出量为379.1 mL±4.67 g VS-1， CPWf为388.6 mL±5.23 g VS-1。CPWu和CPWf的一级动力学模型对甲烷产量的描述最好，其速率常数(k)分别为0.51和0.48 d−1。DAF有效去除浊度和PC，而不妨碍沼气的产生。这项研究的结果增加了咖啡行业的可持续废水管理，并对沼气和能源回收产生了影响，强调了通过厌氧消化产生可再生能源的潜力。图形抽象

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Biomass Conversion and Biorefinery Energy-Renewable Energy, Sustainability and the Environment

CiteScore

7.00

自引率

15.00%

发文量

1358

期刊介绍： Biomass Conversion and Biorefinery presents articles and information on research, development and applications in thermo-chemical conversion; physico-chemical conversion and bio-chemical conversion, including all necessary steps for the provision and preparation of the biomass as well as all possible downstream processing steps for the environmentally sound and economically viable provision of energy and chemical products.