Anaerobic co-biodegradation of polyhydroxyalkanoate and swine manure for volatile fatty acid production: The impact of C/N ratios and microbial dynamics.

Polyhydroxyalkanoate (PHA) is the important biodegradable plastic, however, biodegradation of PHA waste in anaerobic environments emits more CH, a potent greenhouse gas. Bioconversion of PHA waste to useful byproducts - volatile fatty acids (VFAs) is a practical method to upcycle carbon from PHA. In this study, PHA waste was anaerobically co-digested with swine manure (SM) (the typical high nitrogen waste) at different C/N ratios.

Enhanced lactic acid production through enzymatic hydrolysis: Assessing impact of varied enzyme loadings on co-fermentation of swine manure and apple waste.

Anaerobic co-fermentation of swine manure (SM) and apple waste (AW) restricts by the slow hydrolysis of substrates with complex structures, which subsequently leads to low lactic acid (LA) production. Therefore, a novel strategy based on enzymatic pretreatment for improving LA production from anaerobic co-fermentation of SM and AW was proposed in this study. The results indicated that the maximal LA concentration increased from 35.

Lactic acid production with two types of feedstocks from food waste: Effect of inoculum, temperature, micro-oxygen, and initial pH.

Lactic acid (LA) is an important chemical with broad market applications. To optimize LA production, food waste has been explored as feedstock. Due to the wide variety of food waste types, most current research studies have obtained different conclusions.

Enzyme enhanced lactic acid fermentation of swine manure and apple waste: Insights from organic matter transformation and functional bacteria.

Anaerobic co-fermentation is a favorable way to convert agricultural waste, such as swine manure (SM) and apple waste (AW), into lactic acid (LA) through microbial action. However, the limited hydrolysis of organic matter remains a main challenge in the anaerobic co-fermentation process. Therefore, this work aims to deeply understand the impact of cellulase (C) and protease (P) ratios on LA production during the anaerobic co-fermentation of SM with AW.

Effects of self-produced lactic fermentation (SPLF) on GHG and VSC emissions during swine slurry storage.

Self-produced lactic fermentation (SPLF) is a new valued utilization technology, but its impact on gas emission remains unclear. The objective of this study is to investigate the effect of replacing the HSO additive with SPLF on greenhouse gas (GHG), and volatile sulfur compound (VSC) emissions from swine slurry storage in a laboratory-scale study. In this study, SPLF is directed toward producing lactic acid (LA) through the anaerobic fermentation of slurry and apple waste under the most suitable conditions, with the LA concentration kept at 10,000-52000 mg COD/L and the pH remaining within 4.

Revealing mechanism of micro-aeration for enhancing volatile fatty acids production from swine manure.

Micro-aeration is considered a new strategy for improving volatile fatty acids (VFAs) production of agricultural waste. This study investigated the effect and mechanism of micro-aeration of air and oxygen (O) on VFAs production from swine manure. The results showed that Air-micro-aeration had the most significant improvement effect, with the highest VFAs of 8.

Antibiotic removal potential for low greenhouse gas emission process of anaerobic digestion (AD) producing volatile fatty acids (VFAs).

This study aimed to investigate the antibiotic of sulfachloropyridazine (SCP) reduction and its effects on volatile fatty acids (VFAs) accumulation and microbial community structures during the process of anaerobic digestion (AD) producing VFA. Results showed that initial SCP concentrations have a positive correlation with reduction of SCP and accumulation of VFAs. The removal rates of SCP were 22.

Improving production of lactic acid and volatile fatty acids from dairy cattle manure and corn straw silage: Effects of mixing ratios and temperature.

Anaerobic co-fermentation (AcoF) of dairy cattle manure (DCM) and corn straw silage (CSS) for producing lactic acid (LA) and volatile fatty acids (VFAs) was investigated. Batch experiments were conducted at seven different DCM/CSS ratios and at mesophilic and thermophilic temperatures. Results indicated that the highest concentration of LA was 17.

Produce individual medium chain carboxylic acids (MCCA) from swine manure: Performance evaluation and economic analysis.

Environmental issues caused by untreated animal manure require the development of resource recovery from waste through a circular economy approach. Producing medium chain carboxylic acids (MCCA) with higher value than biogas from manure has become promising. The objective of this study was to develop an effective individual MCCA produce process utilizing manure.

Roles of micro-aeration on enhancing volatile fatty acids and lactic acid production from agricultural wastes.

Micro-aeration was proven to be an environmentally friendly strategy for efficiently enhancing volatile fatty acids (VFAs) and lactic acid (LA) production. The roles of micro-aeration on mono-digestion of swine manure (SM) for VFAs production and co-digestion of SM with corn silage (CS) for LA production were investigated, respectively. In this study, micro-aeration increased the maximum VFAs concentration by 20.

Optimization of lactate production from co-fermentation of swine manure with apple waste and dynamics of microbial communities.

Co-anaerobic fermentation (co-AF) of swine manure (SM) and apple waste (AW) has been proved to be beneficial for lactic acid (LA) production. In order to further improve the LA production, three important parameters, namely AW in feedstock, temperature, volatile solids (VS) of feedstock, were evaluated using Box-Behnken design and response surface methodology. The quadratic regression model was developed and interactive effects was found between the three parameters.

Fate of antibiotics during membrane separation followed by physical-chemical treatment processes.

Membrane separation technology has been widely utilised to obtain clean permeate and concentrated nutrients from biogas digested slurry. However, some antibiotics are frequently found in digested slurry. Antibiotic removal during the steps, including paper filtration (PF), hollow-fibre membrane ultrafiltration (HF), nanofiltration (NF) and reverse osmosis (RO), of combined membrane separation processing (CMP) remain poorly understood.

Effect of Pretreatment on Hydraulic Performance of the Integrated Membrane Process for Concentrating Nutrient in Biogas Digestate from Swine Manure.

Nanofiltration (NF) or reverse osmosis (RO) process has been widely applied for concentrating nutrient in biogas digestate. However, efficient pretreatment is key to the sustainable operation of NF or RO. In this study, the combination of NF and RO for concentrating biogas digestate was compared using different pretreatments of hollow fiber ultrafiltration membrane (HFUFM) and ceramic membrane (CUFM).

Bioconversion of swine manure into high-value products of medium chain fatty acids.

This research proposes and demonstrates, for the first time, the utilization of swine manure as a complex feedstock to produce high-value medium chain fatty acids (MCFA). The two-stage anaerobic digestion (AD) carboxylates platform was adopted for the conversion of swine manure to short chain fatty acids (SCFAs) and then SCFAs to MCFA (n-caproate, n-heptanoate, and n-caprylate) with ethanol supplementation. We defined the appropriate initial pH of 10.

Additional function of pasteurisation pretreatment in combination with anaerobic digestion on antibiotic removal.

Pasteurisation pretreatment (PP) in combination with anaerobic digestion (PPAD) is one of the best ways for sterilisation of pathogenic microorganisms in manure. However, the effect of antibiotic residues in manure on PPAD has not been studied. This study investigated the function of PPAD on antibiotic removal and the effect of antibiotic on PPAD performance.

The Combined Process of Paper Filtration and Ultrafiltration for the Pretreatment of the Biogas Slurry from Swine Manure.

The membrane process had been applied for the advanced treatment of pig farm biogas slurry. As studied, this physical pretreatment, with low cost and high efficiency of the suspended solids removal and nutrient retention, is required to control membrane fouling. The combined process of paper filtration and ultrafiltration in a pilot scale was applied in the present study.

Effect of Time and Mixing in Thermal Pretreatment on Faecal Indicator Bacteria Inactivation.

Faecal indicator bacteria of faecal coliform, spp., and faecal are present at high levels in faecal sludge and affect human health. Mesophilic anaerobic digestion cannot reduce faecal indicator bacteria to meet the standards for biosolids; therefore, the thermal pretreatment of faecal sludge is essential.

Antibiotic degradation and microbial community structures during acidification and methanogenesis of swine manure containing chlortetracycline or oxytetracycline.

Anaerobic digestion (AD) has been applied to animal manure stabilization, and antibiotics is frequently found in animal manure. However, antibiotic degradation and microbial community structures during two-stage AD (acidification and methanogenesis) remain poorly understood. This experiments on two-stage anaerobic swine manure digesters were performed to investigate the degradation mechanisms and effects of chlortetracycline (CTC) and oxytetracycline (OTC) on microbial community structures.

Effects of biofilter media depth and moisture content on removal of gases from a swine barn.

Unlabelled: Media depth (MD) and moisture content (MC) are two important factors that greatly influence biofilter performance. The purpose of this study was to investigate the combined effect of MC and MD on removing ammonia (NH), hydrogen sulfide (HS), and nitrous oxide (NO) from swine barns. Biofiltration performance of different MDs and MCs in combination based on a mixed medium of wood chips and compost was monitored.

Effects of anaerobic digestion on chlortetracycline and oxytetracycline degradation efficiency for swine manure.

Manure containing antibiotics is considered a hazardous substance that poses a serious health risk to the environment and to human health. Anaerobic digestion (AD) could not only treatment animal waste but also generate valuable biogas. However, the interaction between antibiotics in manure and the AD process has not been clearly understood.

Study on anaerobic digestion treatment of hazardous colistin sulphate contained pharmaceutical sludge.

Pharmaceutical sludge is considered as a hazardous substance with high treatment and disposal fees. Anaerobic digestion could not only transform the hazardous substance into activated sludge, but also generate valuable biogas. This research had two objectives.

Study on anaerobic treatment of hazardous steel-mill waste rolling oil (SmWRO) for multi-benefit disposal route.

Steel-mill waste rolling oil (SmWRO) is considered as hazardous substance with high treatment and disposal fees. Anaerobic process could not only transform the hazardous substance into activated sludge, but also generate valuable biogas. This study aimed at studying the biochemical methane potential of SmWRO under inoculum to substrate VS ratios (ISRs) of 0.