Optimizing bio-coagulants for brewery wastewater treatment using response surface methodology

Coag-flocculation process was used to treat brewery effluent stream with Detarium Microcarpum seed powder (DMSP) and oyster dried shell powder (ODSP) as coagulants. The proximate analyses of the coagulants were obtained using AOAC standard method. Percentage moisture, ash, fat, crude protein, crude fiber and carbohydrate content were determined for both coagulants. Jar test experiments were employed for the coag-flocculation process and response surface methodology (RSM) optimize the process. A box-Behnken design (BBD) of Design Expert 6.0.8, implementing RSM was used to evaluate the effects and interactions of three factors: coagulant dosage, pH and stirring time on the treatment efficiency. The optimal conditions obtained were coagulant dosage of 100.53mg/L, pH of 2.001 and stirring time of 24.47mins with 90.44% solid particle (SP) removal (desirability value of 1.0) and coagulant dosage of 104.19mg/L, pH of 3.34 and stirring time of 27.54 with 96.55% SP removal (desirability value of 1.0) for DMSP and ODSP, respectively. These agree reasonably with the experimental optimum for both coagulants. A determination coefficient, R2, of 97 and 98%; F-value of 45.8056 and 55.3045; and prob.-value of 1.92E-07 and 2.39E-07 for DMSP and ODSP respectively were used to evaluate the model adequacy.RSM has been demonstrated to be appropriate approach for the optimization of this process.Keywords: Coag-flocculation, Detarium Microcarpum, oyster shell, optimization, response surface methodolog

Computer-aided batch process design, techno-economic and uncertainty analyses of bio-clarified water recovery from south-eastern Nigerian brewery wastewater

Biocoagulation-flocculation-sedimentation (bioclarification) is one of the main wastewater treatment techniques. Despite its effectiveness in treating brewery wastewater for water reuse, the scale-up process for the reclaimed brewery water from wastewater has rarely been documented in the literature. This study presents the computer-aided process design, techno-economic and uncertainty analyses of bioclarified water production from brewery wastewater. The base-case simulation model, process scale-up design and economics were performed in Aspen Batch Process Developer. Process profitability indices (Net Present Value: (NPV), Internal Rate of Return: (IRR) and Payback Time: PBT) were evaluated in a user-defined developed Microsoft-excel version 2018. Monte-Carlo-Simulation in Crystal-Ball-Oracle software was used to perform the sensitivity and uncertainty analyses. The process scale-up simulation results gave annual production capacity (45,000,000 L/year), batch size (9800 L/batch) and annual number of batches produced (4564 batches/year). Base case capacity results showed that the total capital investment, NPV, IRR and PBT are $2,416,358.62,$2,790,608, 36% and 3.27years respectively. Sensitivity analysis shows that production capacity and product selling price have the highest contribution for both NPV and IRR respectively. Certainties of base-case model were 90.27% for the IRR and 99.51% for the NPV. This study showed that brewery wastewater bioclarification scale-up design is feasible

Microwave-assisted extraction proof-of-concept for phenolic phytochemical recovery from Allium Sativum L. (Amaryllidaceous): Optimal process condition evaluation, scale-up computer-aided simulation and profitability risk analysis

Allium Sativum L. (ASL) extract is one of the medicinal and aromatic products used in pharmaceutical, food, cosmetic and perfumery industries. The scientific literature bibliography regarding process scale-up simulation and techno-economics of phenolic extract from ASL Microwave-Assisted Extraction (MAE) is seldom reported. This study presented optimization and techno-economics of phenolic recovery from ASL extraction. Box-benken design extraction experiment was conducted at irradiation power (520 W – 1040 W), extraction time (2- 10 min) and solid-liquid ratio (0.4 – 1 g/100 ml). The extraction conditions that optimized experimental extractible yield and Total Phenolic Content (TPC) evaluated in Box-benken desirability of Response Surface Methodology. Bioactive finger printing of the extract was analyzed using High Performance Liquid Chromatograph (HPLC). Aspen Batch Process Developer was used for the process techno-economic analysis; profitability uncertainty was analyzed using Monte-Carlo Simulation (MCS). Optimal extractible yield (28.62%) and TPC (76.8 mgGAE/g dry extract) were obtained at irradiation time 7.62 min, microwave power 826.67 Watt (63.6%) with solid-liquid ratio 0.55g/100 ml. The HPLC fingerprint revealed bentulinic acid, galic acid, chlorogenic acid, ellagic acid and ferulic acid. Cost of Manufacturing (COM) for 5L, 50L and 500L extractors gave US$1,480, US$ 220 and US$56 respectively. Techno-economic results of 500L extraction capacity with 900 kg/year design gave batch size (0.25 kg), production rate (2 kg/min), cycle time (125 min), discounted net present value (38,133 US$), rate of return (34%) and pay back time (2.94yrs). MCS results show high certainties of achieving base case profitability indices. The study shows that MAE of garlic powder is economically feasible