{"title":"气候温度变化和过大风量对好氧生物反应器中溶解氧和微生物两个关键参数的影响","authors":"Mpho Muloiwa , Julius Musyoka Ndambuki , Caliphs Zvinowanda , Innocentia Velaphi Sibiya","doi":"10.1016/j.sajce.2025.04.001","DOIUrl":null,"url":null,"abstract":"<div><div>The biological treatment process, aerobic bioreactor is essential for biodegradation of nutrients using microbes. The survival of microbes relies on the availability of nutrients and dissolved oxygen (DO). The challenge is that oxygen gas does not dissolve easily in wastewater which motivates plant operators to apply excessive airflow rates to uphold oxygen in the aerobic bioreactor. In addition, the rising climate temperatures suppress DO, which threatens the survival of microbes, risking poor effluent discharge. Hence, the study analyzed the climate temperature changes and excessive airflow rate effect on microbes and DO simultaneously. Climate temperature changes and excessive airflow rate on microbes and DO were analyzed using linear regression, ANOVA, and coefficient of determination (R²). Findings disclosed that climate temperature changes produced R² (0.86) and negative linear regression (0.1076 mg/L) on DO while producing R² (0.59) and positive linear regression (0.168 mg/L) on microbes. Further findings disclosed that excessive airflow rates produced R² (0.84) and positive linear regression (0.0057 mg/L) on DO while producing R² (0.0003) and positive linear regression (0.001 mg/L) on microbes. Overall climate temperatures showed variations on microbes growth <em>(P -</em> <span><math><mrow><mn>8.7424</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mn>9</mn></msup></mrow></math></span> <em>< 0.05)</em> and DO <em>(P -</em> <span><math><mrow><mn>6.301</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mn>29</mn></msup></mrow></math></span> <em>< 0.05)</em> while excessive airflow rates showed no variations on microbes growth <em>(P - 0.7705</em> <em>></em> <em>0.05)</em> and DO <em>(P - 0.98512</em> <em>></em> <em>0.05)</em>. This suggests that climate temperature change will benefit microbes despite DO being suppressed while excessive airflow rates will not benefit microbes but enhance global warming due to emissions released by blowers/pumps.</div></div>","PeriodicalId":21926,"journal":{"name":"South African Journal of Chemical Engineering","volume":"52 ","pages":"Pages 344-351"},"PeriodicalIF":0.0000,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Climate temperature changes and excessive airflow rate effect on two key parameters: Dissolved oxygen and microbes in the biological treatment process-aerobic bioreactor\",\"authors\":\"Mpho Muloiwa , Julius Musyoka Ndambuki , Caliphs Zvinowanda , Innocentia Velaphi Sibiya\",\"doi\":\"10.1016/j.sajce.2025.04.001\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>The biological treatment process, aerobic bioreactor is essential for biodegradation of nutrients using microbes. The survival of microbes relies on the availability of nutrients and dissolved oxygen (DO). The challenge is that oxygen gas does not dissolve easily in wastewater which motivates plant operators to apply excessive airflow rates to uphold oxygen in the aerobic bioreactor. In addition, the rising climate temperatures suppress DO, which threatens the survival of microbes, risking poor effluent discharge. Hence, the study analyzed the climate temperature changes and excessive airflow rate effect on microbes and DO simultaneously. Climate temperature changes and excessive airflow rate on microbes and DO were analyzed using linear regression, ANOVA, and coefficient of determination (R²). Findings disclosed that climate temperature changes produced R² (0.86) and negative linear regression (0.1076 mg/L) on DO while producing R² (0.59) and positive linear regression (0.168 mg/L) on microbes. Further findings disclosed that excessive airflow rates produced R² (0.84) and positive linear regression (0.0057 mg/L) on DO while producing R² (0.0003) and positive linear regression (0.001 mg/L) on microbes. Overall climate temperatures showed variations on microbes growth <em>(P -</em> <span><math><mrow><mn>8.7424</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mn>9</mn></msup></mrow></math></span> <em>< 0.05)</em> and DO <em>(P -</em> <span><math><mrow><mn>6.301</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mn>29</mn></msup></mrow></math></span> <em>< 0.05)</em> while excessive airflow rates showed no variations on microbes growth <em>(P - 0.7705</em> <em>></em> <em>0.05)</em> and DO <em>(P - 0.98512</em> <em>></em> <em>0.05)</em>. This suggests that climate temperature change will benefit microbes despite DO being suppressed while excessive airflow rates will not benefit microbes but enhance global warming due to emissions released by blowers/pumps.</div></div>\",\"PeriodicalId\":21926,\"journal\":{\"name\":\"South African Journal of Chemical Engineering\",\"volume\":\"52 \",\"pages\":\"Pages 344-351\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2025-04-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"South African Journal of Chemical Engineering\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S1026918525000356\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"Social Sciences\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"South African Journal of Chemical Engineering","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1026918525000356","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"Social Sciences","Score":null,"Total":0}
Climate temperature changes and excessive airflow rate effect on two key parameters: Dissolved oxygen and microbes in the biological treatment process-aerobic bioreactor
The biological treatment process, aerobic bioreactor is essential for biodegradation of nutrients using microbes. The survival of microbes relies on the availability of nutrients and dissolved oxygen (DO). The challenge is that oxygen gas does not dissolve easily in wastewater which motivates plant operators to apply excessive airflow rates to uphold oxygen in the aerobic bioreactor. In addition, the rising climate temperatures suppress DO, which threatens the survival of microbes, risking poor effluent discharge. Hence, the study analyzed the climate temperature changes and excessive airflow rate effect on microbes and DO simultaneously. Climate temperature changes and excessive airflow rate on microbes and DO were analyzed using linear regression, ANOVA, and coefficient of determination (R²). Findings disclosed that climate temperature changes produced R² (0.86) and negative linear regression (0.1076 mg/L) on DO while producing R² (0.59) and positive linear regression (0.168 mg/L) on microbes. Further findings disclosed that excessive airflow rates produced R² (0.84) and positive linear regression (0.0057 mg/L) on DO while producing R² (0.0003) and positive linear regression (0.001 mg/L) on microbes. Overall climate temperatures showed variations on microbes growth (P -< 0.05) and DO (P -< 0.05) while excessive airflow rates showed no variations on microbes growth (P - 0.7705>0.05) and DO (P - 0.98512>0.05). This suggests that climate temperature change will benefit microbes despite DO being suppressed while excessive airflow rates will not benefit microbes but enhance global warming due to emissions released by blowers/pumps.
期刊介绍:
The journal has a particular interest in publishing papers on the unique issues facing chemical engineering taking place in countries that are rich in resources but face specific technical and societal challenges, which require detailed knowledge of local conditions to address. Core topic areas are: Environmental process engineering • treatment and handling of waste and pollutants • the abatement of pollution, environmental process control • cleaner technologies • waste minimization • environmental chemical engineering • water treatment Reaction Engineering • modelling and simulation of reactors • transport phenomena within reacting systems • fluidization technology • reactor design Separation technologies • classic separations • novel separations Process and materials synthesis • novel synthesis of materials or processes, including but not limited to nanotechnology, ceramics, etc. Metallurgical process engineering and coal technology • novel developments related to the minerals beneficiation industry • coal technology Chemical engineering education • guides to good practice • novel approaches to learning • education beyond university.