Piggery Wastewater Treatment Research Articles

Ammonium Removal by a Newly Isolated Heterotrophic Nitrification-Aerobic Denitrification Bacteria Pseudomonas Stutzeri SDU10 and Its Potential in Treatment of Piggery Wastewater.

A strain SDU10 was isolated from swine manure compost and identified as Pseudomonas stutzeri SDU10. It demonstrated excellent capability in NH4+-N removal. Optimal conditions of NH4+-N removal were determined, which were sodium acetate as the optimal carbon source, carbon to nitrogen (C/N) ratio of 10, temperature of 30°C, pH of 7.0. Especially, P. stutzeri SDU10 could remove high concentration NH4+-N of 1500.0 and 2000.0mg/l in 120h with the NH4+-N removal rates of 91.1% and 61.6%, respectively. In batch experiments, the highest NH4+-N removal rate of 97.6% and chemical oxygen demand (COD) removal rate of 94.2% were obtained at initial C/N ratio 10 during piggery wastewater treatment using P. stutzeri SDU10. Results showed that P. stutzeri SDU10 had the potential for treatment of wastewater of high NH4+-N concentration.

Establishing a Smart Farm-Scale Piggery Wastewater Treatment System with the Internet of Things (IoT) Applications

The conventional piggery wastewater treatment system is mainly a manual operation system which may be well managed by experienced technicians. However, the pig farmers must simultaneously manage their pig production as well as their on-farm wastewater treatment facility. For this study, Internet of Things (IoT) applications were introduced on a 1000-pig farm to establish a smart piggery wastewater treatment system, which was upgraded from a self-developed fully automatic wastewater treatment system. Results showed that the removal efficiency of biochemical oxygen demand (BOD), chemical oxygen demand (COD), and suspended solids (SS) of the piggery wastewater based on the sensor data before and after water quality sensor calibration were 89%, 94%, and 93%, and 94%, 86%, and 96%, respectively. Moreover, the removal efficiency of BOD, COD, and SS of the piggery wastewater based on the analytical chemical data before and after water quality sensor calibration were 93%, 89%, and 97%, and 94%, 86%, and 96%, respectively. Experimental results showed that overall removal efficiency of BOD, COD, and SS of the piggery wastewater after water quality sensor calibration were 94%, 86–87%, and 96%, respectively. Results revealed that the farm-scale smart piggery wastewater treatment system was feasible to be applied and extended to more commercial pig farms for establishing sustainable pig farming.

TREATMENT EFFICIENCY OF PIGGERY WASTEWATER BY SURFACE AND HORIZONTAL SUBSURFACE FLOW CONSTRUCTED WETLANDS

Constructed wetlands have been used to treat various types of wastewaters such as urban runoff, acid mine drainage, municipal, industrial, and livestock wastewaters. This study is conducted to evaluate the effectiveness of two constructed wetlands (surface and horizontal subsurface flows) for piggery wastewater treatment after biogas process. The wetland plant Phragmites australis Cav. was used in 45 days for the experiments. The CWs were designed to treat up to 100 liters/day with the hydraulic retention time (HRT) of 3 days. Parameters including pH, COD, TSS, NH4+-N, total nitrogen (TN) and total phosphorus (TP) were measured. The pH of the CWs system was in the range of 6.7 to 7.3. The results showed that the horizontal subsurface flow CW had better treatment performance compared to the surface flow system. The removal efficiency of TP, TSS, COD, TN and NH4+-N by surface flow CW was 80, 60, 66, 60 and 65%, respectively while those by horizontal subsurface flow system was 86, 78, 74.6, 67.1 and 74.2%, respectively. The water quality of the effluents of both two CWs met the Vietnamese standards for livestock wastewater (QCVN62/2016-BTNMT, column B).

A systematic optimization of piggery wastewater treatment with purple phototrophic bacteria

The increase in natural water bodies pollution caused by intensive animal farming requires the development of innovative sustainable treatment processes. This study assessed the influence of piggery wastewater (PWW) load, air dosing, CO2/NaHCO3− supplementation and pH control on PWW treatment by mixed cultures of purple phototrophic bacteria (PPB) under infrared radiation in batch photobioreactors. PPB was not able to grow in raw PWW but PWW dilution prevented inhibition and supported an effective light penetration. Despite the fact that PPB were tolerant to O2, carbon recovery decreased in the presence of air (induced by stripping). CO2 supplementation was identified as an effective strategy to maximize the removal of carbon during PPB-based PWW treatment with removal efficiencies of 72% and 74% for TOC and VFAs. However, the benefits derived from CO2 addition were induced by the indirect pH control exerted in the cultivation medium. Thus, PPB supported an optimal pollutant removal performance at pH 7, with removal efficiencies of 75%, 39% and 98% for TOC, TN and VFAs.

Screening of a Chlorella-bacteria consortium and research on piggery wastewater purification

The aerobic formers of Exiguobacterium and Bacillus licheniformis were screened to construct a Chlorella-bacteria consortium for the piggery wastewater treatment. The optimal consortia of Chlorella-Exiguobacterium (C.v-E.x) and Chlorella-Exiguobacterium/Bacillus licheniformis (C.v-E.x/B.l) were designated to purify wastewater scaled-up in a column photobioreactor. The results showed that the rates of contaminant removal and cell growth of the Chlorella-bacteria consortium were all higher than those of the axenic Chlorella system and pure bacterial system. The C.v-E.x consortium had the best purification effect, and the concentrations of total phosphorus (TP) and ammonia nitrogen (NH4+-N) were reduced to 1.8 mg L−1 and 35.0 mg L−1 after 12 days, respectively. The final removal rates of total nitrogen (TN), TP, NH4+-N, and chemical oxygen demand (COD) were 78.3%, 87.2%, 84.4%, and 86.3%, respectively, and these levels were below the wastewater discharge standard (GB18596-2001, China). The mutualistic interactions between Chlorella and its coculture bacteria were explored by detecting total inorganic carbon (TIC), net photosynthetic activity (NPA), dissolved oxygen (DO), pH, and nitrogen-related enzyme activity. The results showed that the C.v-E.x consortium had a higher NPA (70.8% increase), DO concentration (172.4% increase), and TIC concentration (71.0% increase) and maintained a low pH 9.3 compared with the axenic C. vulgaris system. Therefore, the synergistic interactions of cell growth promotion and the exchange of carbon and oxygen between microalgae and bacteria were identified. The detection of nitrogen-related enzymatic activities in the photosynthesis pathway of Chlorella demonstrated that Exiguobacterium obviously improved the activities of nitrate reductase (NR), nitrite reductase (NiR), glutamine synthetase (GS), and glutamate synthetase (GOGAT) by 94.2%, 57.5%, 58.6%, and 79.4%, respectively. This result indicated that cocultured bacteria might secrete some metabolites as enzyme activators, and there was a synergistic mechanism in the enzymology between microalgae and bacteria. The research provides a reference for the wastewater resourceful treatment by microalgae-bacteria consortia.

Effects caused by chlortetracycline and oxytetracycline in anaerobic digestion treatment of real piggery wastewater: Treatment efficiency and bacterial diversity

The treatment efficiency and bacterial diversity caused by chlortetracycline (CTC) and oxytetracycline (OTC) in anaerobic digestion treatment of real piggery wastewater were studied by polymerase chain reaction - denaturing gradient gel electrophoresis (PCR-DGGE) and real-time PCR. The COD removal efficiency and methane production were inhibited with the increasing concentration of CTC and OTC. The antagonism of CTC and OTC on methane production was observed, the inhibition rate was expanded to 55.46% from 18.34%; antagonism and enhancement were observed on inhibition rate of COD removal efficiency, and the inhibition rate was expanded to 24.84% from 4.16%. The bacterial diversity and similarities of each group were decreased with the increasing concentration of CTC and OTC. The identified species Thermotogae bacterium, Bacteroidetes bacterium, Chloroflexi bacterium, Eubacterium, Mesophilic bacterium, etc. were beneficial for COD removal and biodegradation of CTC and OTC. The quantitative fluorescence analysis was opposite to the rule of bacterial diversity by real-time PCR.

Nutrients removal from piggery wastewater coupled to lipid production by a newly isolated self-flocculating microalga Desmodesmus sp. PW1

A newly isolated microalgal strain, Desmodesmus sp. PW1, possessing not only high potential for removing nitrogen and phosphorous from piggery wastewater but excellent self-flocculating ability, was provided here. Strain PW1 grew well in diluted and undiluted piggery wastewater, and could effectively remove total nitrogen and total phosphorus with removal rates up to 90% and 70%, respectively. In the laboratory scale by 30-L photobioreactor, microalga also performed well in TN (65.3%) and TP (83.5%) removal. Strain PW1 cultivated in the stationary phase achieved high self-flocculating efficiency (>90%) in 2.5 h of settling; meanwhile, temperature and pH slightly influenced on the flocculation. The potential mechanism on self-flocculation was considered related to hydrophobic extracellular polymeric substances. Furthermore, the fatty acid compositions of PW1 were mainly hexadecanoic acid, oleic acid and linoleic acid. Taken together, Desmodesmus sp. PW1 was the promising candidate to overcome the microalgae harvesting problem in piggery wastewater treatment.

Start-up of partial nitrification-Anammox (PN/A) process treating piggery wastewater

Start-up of partial nitrification-Anammox (PN/A) process treating piggery wastewater

The effect of using pig manure as an internal carbon source in a traditional piggery wastewater treatment system for biological denitrification

Due to a low ratio of chemical oxygen demand (COD) to total nitrogen (TN) and poor biodegradability of digested piggery wastewater, lack of a carbon source in subsequent biological treatment limits denitrification, resulting in an accumulation of NO2-N and NO3-N and a low denitrification efficiency. In this project, combined ultrasonication/alkali treatment of pig manure was used to generate a source of pig manure carbon source(PMC). This report mainly discusses the effects of adding the PMC on subsequent biological denitrification and microbial community changes. The experimental results showed that in subsequent biological treatment with the addition of 1.78% PMC, the effluent NO2-N and NO3-N were 0.02 mg·L−1 and 0.90 mg·L−1, respectively. The TN removal percentage was 72.29%, which was 62.29% higher than that obtained without an added carbon source and 36.74% higher than that obtained with added raw wastewater carbon (RWC). High-throughput sequencing revealed that the relative abundances of the dominant microflora Thauera and Thermomonas, which are related to denitrification, increased from 1.13% and 0.55% to 6.19% and 4.69%, respectively, after the addition of PMC. The addition of PMC improved the denitrification of digested piggery wastewater in subsequent biological treatment, and the denitrification effect was obvious and could enable waste resource utilization.

Swine waste: A reservoir of high-risk blaNDM and mcr-1

Multidrug resistance associated with pigs not only affects pig production but also threatens human health by influencing the farm surrounding and contaminating the food chain. This paper focused on the occurrence and prevalence of high-risk resistance genes (using blaNDM and mcr-1 as marker genes) in two Chinese swine farms, and investigated their fate and seasonal changes in piggery wastewater treatment systems (PWWTSs). Results revealed that blaNDM and mcr-1 were prevalent in both confined swine farms, and even prevailed through various processing stages of PWWTSs. Moreover, the abundance of blaNDM and mcr-1 in winter was higher than that in summer, with 0.01–1.01 logs variation in piggery wastewater. Of concern is that considerable amounts of blaNDM and mcr-1 were present in final effluent that is applied to farmland (up to 102–104copies/mL), raising the risk of propagation to indigenous bacteria. Worse still, those pig-derived isolates harboring the blaNDM/mcr-1 gene were confirmed to spread multidrug resistance to other bacteria, which further increased their dissemination potential in agricultural environment. This study highlights the prevalence of blaNDM and mcr-1 in swine farms, meanwhile, also emphasizes the necessary to mitigate the release and propagation of these high-risk genes from swine farms following land fertilization and wastewater usage.

Microalgae cultivation for municipal and piggery wastewater treatment in Brazil

Microalgae are a source of high-valuable products covering a wide range of applications. However, costs incurred by cultivating them make it an expensive process. The combination of wastewater treatment and microalgae cultivation is a viable option to reduce expenses related to cultivation. However, municipal wastewater from the centralized Brazilian sanitation system is highly diluted, and it is technically and economically impractical to use it for microalgae cultivation. As an alternative, diluted effluent can be mixed with a different kind of wastewater, aiming to increase the nutrient concentration (carbon, nitrogen and phosphorus) for microalgae cultivation. In this study, microalgae cultivation and wastewater mixture (municipal and piggery wastewater) treatment were monitored for four weeks. The pilot treatment system consisted of UASB as pre-treatment and Chlorella sorokiniana cultivation in three flat panel photobioreactors. High UASB efficiency was obtained in organic matter removal (> 90%), even with a large variability of initial mixture characteristics. C. sorokiniana production reached about 1 g L−1, with an average removal of dissolved inorganic carbon, orthophosphate and ammonia around 46 to 56%, 40 to 60% and 100%, respectively. Possible solutions to improve the microalgae growth and the system treatment are discussed.

Lab‐scale testing of operation parameters for algae based treatment of piggery wastewater

AbstractBACKGROUNDMicroalgae–bacteria‐based processes are among the most promising low‐cost technologies to treat livestock wastewaters. The current literature reports the need for pretreatment or dilution of piggery wastewater for adequate microalgal growth. The aim of this study is to optimize the potential of microalgal–bacterial communities to treat undiluted and untreated piggery wastewater by investigating the influence of some operational parameters such as phosphorus and CO2 availability and hydraulic retention time on the nitrogen removal efficiency and biomass productivity.RESULTSThe microalgal community (dominated by Chlorella spp.) developed quickly and remained quite stable. The rates of biomass production and NH4‐N removal were 55 ± 30 mg TSS L−1 day−1 and 13 ± 3 mg NH4‐N L−1 day−1 respectively. CO2 adjustment had a positive effect on microalgal growth and NH4‐N removal.CONCLUSIONData confirm the ability of the microalgal–bacterial consortium to grow on undiluted and untreated piggery wastewater under semi‐continuous conditions. Synergy between algae and bacteria seems positive since photosynthesis produces the oxygen needed for ammonia oxidation. © 2019 Society of Chemical Industry

Effective removal of nitrate by denitrification re-enforced with a two-stage anoxic/oxic (A/O) process from a digested piggery wastewater with a low C/N ratio

The combined process of a long-term biogas digester and double anoxic/oxic tanks is very commonly used in piggery wastewater treatment in South China, but the effluent does not meet the discharge standard of total nitrogen (TN) and chemical oxygen demand (CODCr) due to a low C/N ratio and insufficient organic carbon in digested piggery wastewater. Thus, a typical two-stage anoxic/oxic (A1/O1/A2/O2) process, which is widely used to treat digested piggery wastewater in the engineering application, was selected for study on a laboratory scale. Finally, the average removal efficiency of ammonia nitrogen in the two-stage AO process was 98.7%; at the same time, the content of nitrate increased to 180–190 mg/L. To further eliminate nitrogen, an anaerobic tank (S1), which was equipped the sludge that was acclimated in our laboratory by a high nitrogen loading slurry, was employed to treat the effluent from the two-stage AO process and contributed more than 70% removal efficiency. Further analysis showed that ammonia-oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) in the O1 and O2 tanks together contributed to the conversion of ammonia nitrogen to nitrate, but the process of heterotrophic denitrification was inhibited in the A1 and A2 tanks because of insufficient carbon sources. In addition, most of the nitrate concentration was reduced under conditions with insufficient carbon sources, while Thauera-dominated the bacterial population in the sludge sample of the S1 tank.

Assessing the potential of purple phototrophic bacteria for the simultaneous treatment of piggery wastewater and upgrading of biogas

The potential of purple phototrophic bacteria (PPB) for the simultaneous treatment of piggery wastewater (PWW) and biogas upgrading was evaluated batchwise in gas-tight photobioreactors. PWW dilution was identified as a key parameter determining the efficiency of wastewater treatment and biomethane quality in PPB photobioreactors. Four times diluted PWW supported the most efficient total organic carbon (TOC) and total nitrogen removals (78% and 13%, respectively), with CH4 concentrations of 90.8%. The influence of phosphorous concentration (supplementation of 50 mg L−1 of P-PO43−) on PPB-based PWW treatment coupled to biogas upgrading was investigated. TOC removals of ≈60% and CH4 concentrations of ≈90.0% were obtained regardless of phosphorus supplementation. Finally, the use of PPB and algal-bacterial consortia supported CH4 concentrations in the upgraded biogas of 93.3% and 73.6%, respectively, which confirmed the potential PPB for biogas upgrading coupled to PWW treatment.

Co-cultivation of Rhodotorula glutinis and Chlorella pyrenoidosa to improve nutrient removal and protein content by their synergistic relationship

With the continuous development of the livestock breeding industry, the amount of piggery wastewater discharged increases year by year, and the pressure of controlling environmental pollution continuously increases. A novel method using a co-culture of Chlorella pyrenoidosa and Rhodotorula glutinis in piggery wastewater was proposed in this study, which was aimed at treating piggery wastewater and producing useful products. The results showed that the optimal inoculum ratio of algae to yeast was 3 : 1 in the wastewater, which achieved the removal efficiencies of 58.53%, 36.07%, 33.20% and 56.25% for ammoniacal nitrogen (NH3-N), total nitrogen (TN), total protein (TP) and chemical oxygen demand (COD), respectively, after 6 d. The synergistic relationship of C. pyrenoidosa and R. glutinis was preliminarily validated using the oxygen/carbon dioxide exchange balance and scanning electron microscopy images. The co-cultivation system gained 59.8% (w/w) protein within 5 d which can be used as a feed additive, and produces aquatic animals with better growth and quality. Thus, the 1000 litre pilot scale bioreactor was used indoors and removed 82.65% of TN, 53.51% of TP, 93.48% of NH3-N and 85.44% of COD in 21 d which gave a better performance for TN (p < 0.05) than the bench scale results. This system improves the nutrition removal and protein production efficiencies, and is a promising method for piggery wastewater treatment and the pig breeding industry.

A systematic comparison of the potential of microalgae-bacteria and purple phototrophic bacteria consortia for the treatment of piggery wastewater

This study evaluated the performance of two open-photobioreactors operated with microalgae-bacteria (PBR-AB) and purple photosynthetic bacteria (PBR-PPB) consortia during the treatment of diluted (5%) piggery wastewater (PWW) at multiple hydraulic retention times (HRT). At a HRT of 10.6 days, PBR-AB provided the highest removal efficiencies of nitrogen, phosphorus and zinc (87 ± 2, 91 ± 3 and 98 ± 1%), while the highest organic carbon removals were achieved in PBR-PPB (87 ± 4%). The decrease in HRT from 10.6, to 7.6 and 4.1 day caused a gradual deterioration in organic carbon and nitrogen removal, but did not influence the removal of phosphorus and Zn in both photobioreactors. The decrease in HRT caused a severe wash-out of microalgae in PBR-AB and played a key role in the structure of bacterial population in both photobioreactors. In addition, batch biodegradation tests at multiple PWW dilutions (5, 10 and 15%) confirmed the slightly better performance of algal-bacterial systems regardless of PWW dilution.

Development and evaluation of a constructed pilot-scale horizontal subsurface flow wetland treating piggery wastewater

Abstract This paper reports on the development and evaluation of a pilot horizontal subsurface flow constructed wetland (HSSFCW) for removal of biochemical oxygen demand (BOD), chemical oxygen demand (COD), total dissolved solids (TDS), total nitrogen (TN) and total phosphorus (TP) from primary piggery wastewater. Two locally available plants, Pennisetum clandestinum and Pennisetum purpureum, were planted in two of three cells while the remaining unplanted cell served as the control. Monitoring of the wetland influent and effluent wastewater was carried out every two weeks for 7 months. The study revealed successful treatment of the wastewater by the wetland in terms of BOD, COD, TDS, TN and TP effluent compliance with Nigerian discharge standards. Average removal efficiencies were 66.53, 64.95, and 60.27% for BOD5; 44.85, 41.61 and 36.37% for COD; 63.61, 58.27 and 52.88% for TDS; 62.49, 58.89 and 50.14% for TN and 48.53, 44.91 and 41.27% for TP for the three wetland cells including the control respectively. Planted cells achieved the highest removal efficiency with no significant difference in pollutant removal between the two planted cells indicating their suitability for use as wetland plants. Effluent concentrations were within FEPA discharge limits except TP. The performance of the constructed wetland suggests that HSSFCW could be a suitable alternative technology for on-farm treatment of piggery wastewater in Nigeria. The study has provided a starting point for the use of HSSFCW and gives insight of the potential application of this technology for on- farm pollution control in Nigeria.

Piggery wastewater treatment by aerobic granular sludge: Granulation process and antibiotics and antibiotic-resistant bacteria removal and transport

The aim of this work was to study the responses of aerobic granulation process to antibiotics and investigate the antibiotics and antibiotic-resistant bacteria (ARB) removal and transport. Results showed that aerobic granular sludge (AGS) was dominant in the bioreactor at day 45, and the relatively high protein content from tightly bound extracellular polymeric substances (TB-EPS) facilitated aerobic granulation and maintained biomass stabilization. The protein contents in EPS and TB-EPS were positively correlated with relative hydrophobicity, thereby improving the adsorption capacity among hydrophobic particles. The chemical oxygen demand (COD), NH3-N, and total N removal efficiencies were 98.0%, 97.0%, and 92.4%, respectively. Five antibiotics, including kanamycin, tetracycline, ciprofloxacin, ampicillin, and erythromycin, were examined in piggery wastewater, with concentrations up to the concentration range of 29.4–44.1 µg/l, and the total antibiotics removal rate reached up to 88.4% ± 4.5%. A total of 5.2% of the total antibiotics were discharged from bioreactor, and 62.5% of the total antibiotics were degraded, and 32.3% of total antibiotics were adsorbed by aerobic granules. The presence of antibiotics rarely exhibited an influence on AGS formation, and the relatively high microbial activity of aerobic granules was beneficial to antibiotics removal. The ARB removal rate increased up to 89.4% ± 3.3%, but a large amount of ARB was enriched in aerobic granules.

Treatment of duck house wastewater by a pilot-scale sequencing batch reactor system for sustainable duck production.

The objective of this study is trying to solve water pollution problems related to duck house wastewater by developing a novel duck house wastewater treatment technology. A pilot-scale sequencing batch reactor (SBR) system using different hydraulic retention times (HRTs) for treating duck house wastewater was developed and applied in this study. Experimental results showed that removal efficiency of chemical oxygen demand in untreated duck house wastewater was 98.4, 98.4, 87.8, and 72.5% for the different HRTs of 5, 3, 1, and 0.5 d, respectively. In addition, removal efficiency of biochemical oxygen demand in untreated duck house wastewater was 99.6, 99.3, 90.4, and 58.0%, respectively. The pilot-scale SBR system was effective and deemed capable to be applied to treat duck house wastewater. It is feasible to apply an automatic SBR system on site based on the previous case study of the farm-scale automatic SBR systems for piggery wastewater treatment.

High prevalence and dissemination of β-lactamase genes in swine farms in northern China

β-Lactamase (extended-spectrum β-lactamase (ESBL)/AmpC/carbapenemase)-encoding genes, primarily discovered in clinical settings, are increasingly recovering from the environment, thus posing potential threats to public health. This paper addresses the occurrence of high-risk β-lactamase genes (bla genes) in Chinese swine farm and its surrounding farmland, and investigated their seasonal variation and fate in piggery wastewater treatment system (PWWTS) using real-time quantitative PCR. It is observed that blaTEM-1, blaGES-1,blaOXA-1 and blaAmpC were the dominant bla genes in swine farms, which were present in all pig feces, and prevailed through each treatment stage of PWWTSs. Furthermore, bla genes were more abundant in winter than that in summer, with 0.01–1.65 logs variation in swine wastewater. Troublesomely, significant bla gene levels were still discharged via the final effluents (up to 106 copies/mL) into farmland, resulting in the increase of bla gene abundance in soil (approximately 1–3 orders of magnitude). The discharge of bla genes in wastewater from swine farm highlights the need to mitigate the persistence and spreading of these elevated bla genes in agricultural systems.