Assessment of Protein-Rich Cheese Whey Waste Stream as a Nutrients Source for Low-Cost Mixed Microbial PHA Production

The critical step in the mixed microbial cultures (MMC) polyhydroxyalkanoates (PHA) production process is the selection of an MMC enriched in an efficient PHA-accumulating organism, usually requiring growth-nutrients supplementation. This study aimed at assessing cheese whey (CW) proteins as a source of nitrogen for PHA-producing MMC, thus eliminating or reducing the need for nutrients supplementation. The selection reactor, operated with fermented CW, under a feast–famine regime, was initially supplemented with ammonia–nitrogen in a C/N ratio of 100/15 (Cmol/Nmmol), which was gradually reduced until eliminated, in order to select a culture capable of using CW proteins nitrogen. Decreasing nitrogen supplementation from a C/N ratio of 100/10 to 100/7.5 lead to significant microbial community changes, and reduced the MMC PHA-storing capacity, storage yield, and PHA productivity, decreasing by 30%, and over 45%, respectively. The PHA-storing capacity further deteriorated as nitrogen supplementation was reduced, despite increased protein-uptake. Results show that a culture enriched in PHA-accumulators capable of using proteins as sole nitrogen source could not be attained. In conclusion, this work reports for the first time that an easily bioavailable nitrogen source is required for efficiently selecting PHA-accumulating cultures. Based on the results obtained from this work, a pilot scale plant (two reactors of 100 L) fed with cheese whey for production of PHA is currently being successfully operated under the scope of the YPACK EU project, in which the selection reactor is supplemented with nitrogen (ammonia) from a total C/N ratio of 100/10.

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Polyhydroxyalkanoate (PHA) production from sludge and municipal wastewater treatment

Water Science & Technology ◽

10.2166/wst.2013.643 ◽

2013 ◽

Vol 69 (1) ◽

pp. 177-184 ◽

Cited By ~ 62

Author(s):

F. Morgan-Sagastume ◽

F. Valentino ◽

M. Hjort ◽

D. Cirne ◽

L. Karabegovic ◽

...

Keyword(s):

Wastewater Treatment ◽

Activated Sludge ◽

Municipal Wastewater ◽

Storage Capacity ◽

Waste Treatment ◽

Pilot Scale ◽

Municipal Wastewater Treatment ◽

Solid Waste Treatment ◽

Pha Production ◽

Eu Project

Polyhydroxyalkanoates (PHAs) are biodegradable polyesters with comparable properties to some petroleum-based polyolefins. PHA production can be achieved in open, mixed microbial cultures and thereby coupled to wastewater and solid residual treatment. In this context, waste organic matter is utilised as a carbon source in activated sludge biological treatment for biopolymer synthesis. Within the EU project Routes, the feasibility of PHA production has been evaluated in processes for sludge treatment and volatile fatty acid (VFA) production and municipal wastewater treatment. This PHA production process is being investigated in four units: (i) wastewater treatment with enrichment and production of a functional biomass sustaining PHA storage capacity, (ii) acidogenic fermentation of sludge for VFA production, (iii) PHA accumulation from VFA-rich streams, and (iv) PHA recovery and characterisation. Laboratory- and pilot-scale studies demonstrated the feasibility of municipal wastewater and solid waste treatment alongside production of PHA-rich biomass. The PHA storage capacity of biomass selected under feast–famine with municipal wastewater has been increased up to 34% (g PHA g VSS−1) in batch accumulations with acetate during 20 h. VFAs obtained from waste activated sludge fermentation were found to be a suitable feedstock for PHA production.

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Integrated constructed wetland systems: design, operation, and performance of low-cost decentralized wastewater treatment systems

Water Science & Technology ◽

10.2166/wst.2007.140 ◽

2007 ◽

Vol 55 (7) ◽

pp. 155-161 ◽

Cited By ~ 17

Author(s):

L.L. Behrends ◽

E. Bailey ◽

P. Jansen ◽

L. Houke ◽

S. Smith

Keyword(s):

Wastewater Treatment ◽

Constructed Wetland ◽

Low Cost ◽

Nitrate Removal ◽

Systems Design ◽

Pilot Scale ◽

Ammonia Nitrogen ◽

Surface Flow ◽

Treatment Technology ◽

Decentralized Market

Several different types of constructed wetland systems are being used as decentralized treatment systems including surface-flow, subsurface-flow, vertical-flow, and hybrid systems. Archetypical wetland systems have design strengths and weaknesses, and therefore it should be possible to design combined (integrated) systems to optimize a number of important treatment processes. This study provides comparative efficacy data for two integrated wetland treatment systems (IWTS) designed to enhance treatment of medium strength wastewater generated from a pilot-scale intensive fish farm. Results from the twenty eight months study included consistently high removal of COD (84%+) and ammonia nitrogen (93%) in both systems. Initially, phosphorus removal was also high (>90%) in both systems, but removal efficacy declined significantly over time. Nitrate removal was significantly better in the system that provided sequential aerobic and anoxic environments. Short hydraulic retention times coupled with sustained removal of COD and ammonia indicate that the ReCip components could be a least-cost wastewater treatment technology in the decentralized market sector.

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Nitrogen removal during leachate treatment: comparison of simple and sophisticated systems

Water Science & Technology ◽

10.2166/wst.2004.0358 ◽

2004 ◽

Vol 50 (6) ◽

pp. 45-52 ◽

Cited By ~ 10

Author(s):

J.-L. Vasel ◽

H. Jupsin ◽

A.P. Annachhatre

Keyword(s):

Removal Rate ◽

Low Cost ◽

Operating Time ◽

Pilot Scale ◽

Ammonia Nitrogen ◽

Ammonia Removal ◽

Full Scale ◽

Leachate Treatment ◽

Batch Mode ◽

Treatment Comparison

Membrane bioreactors (MBR) have become common in treating municipal wastewaters. Applied to leachates treatment MBR were also successful with pilot scale experiments and full-scale facilities as well. We succeeded previously in designing an efficient nitrificationÐdenitrification process with an ethylene glycol byproduct as carbon source for denitrification. Moreover, an unexpectedly high inert COD removal efficiency was also observed in the full-scale MBR facility thereby making it possible to increase the operating time of the final GAC (Granulated Activated Carbon) adsorber. Since MBR are very sophisticated systems. Simpler and “lower” cost systems can also be considered. For example it is possible to nitrify leachates from sanitary landfill using a simple infiltrationÐpercolation technique with a low energy cost. To validate previously published laboratory experiments, a semi industrial-scale pilot installation was installed at the Montzen landfill site (Belgium). The process is based on infiltrationÐpercolation through a granular bed. This well known process was modified to increase the load, notably by changing the support medium, adding an electric fan that is run intermittently and maintaining temperatures greater than 15°C. The new material is a type of granular calcium carbonate with a large specific surface area. These technical improvements enabled the system to nitrify up to 0.4 kg NH4+-N/m3 of reactor bed per day at a hydraulic load of 0.35 m.d-1, with an ammonia removal rate in the range of 80 to 95%. Despite the high ammonia nitrogen inlet concentrations, this system exhibits remarkable nitrification efficiency. Moreover, these performances are achieved in a batch mode system without recirculation or dilution processes. If complete nitrification is needed, it can be obtained in a second in series of bioreactors. The system can be classified as a low cost process. An international patent is pending. Possible performances of those systems were compared with the usual methods for leachates treatment.

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Ammonia Recovery from Digestate Using Gas-Permeable Membranes: A Pilot-Scale Study

Environments ◽

10.3390/environments8120133 ◽

2021 ◽

Vol 8 (12) ◽

pp. 133

Author(s):

Berta Riaño ◽

Beatriz Molinuevo-Salces ◽

Matías B. Vanotti ◽

María Cruz García-González

Keyword(s):

Pilot Scale ◽

Ammonia Nitrogen ◽

Land Application ◽

Frequent Change ◽

Permeable Membrane ◽

A Value ◽

Trapping Solution ◽

Ammonia Recovery ◽

Total Ammonia ◽

Eu Project

The reduction and recovery of nitrogen (N) from anaerobically digested manure (digestate) is desirable to mitigate N-related emissions, mainly ammonia and nitrate, derived from digestate land application in nutrient-saturated zones. This work reports the results of a gas-permeable membrane (GPM) pilot-scale plant to recover ammonia from digestate in the framework of the EU project Ammonia Trapping. The total ammonia nitrogen (TAN) concentration in digestate was reduced by 34.2% on average (range 9.4–57.4%). The recovery of TAN in the trapping solution in the form of a (NH4)2SO4 solution averaged 55.3% of the removed TAN, with a TAN recovery rate of 16.2 g N m−2 d−1 (range between 14.5 and 21.0 g N m−2 d−1). The TAN concentration in the trapping solution achieved a value of up to 35,000 mg N L−1. The frequent change of the trapping solution has been proven as an efficient strategy to improve the overall performance of the GPM technology.

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Distribution of heterotrophic and autotrophic organisms in a biological aerated filter

Water Practice & Technology ◽

10.2166/wpt.2008.058 ◽

2008 ◽

Vol 3 (3) ◽

Author(s):

O. González-Barceló ◽

S. González-Martínez

Keyword(s):

Municipal Wastewater ◽

Wastewater Treatment Plants ◽

Low Cost ◽

Ammonia Nitrogen ◽

Organic Load ◽

Homogeneous Distribution ◽

Municipal Wastewater Treatment ◽

Filter Media ◽

Aerated Filter ◽

Secondary Settling

Biological aerated filtration is a viable option for small municipal wastewater treatment plants. A low cost filter media was obtained by triturating volcanic rock. An apparent porosity of 46 % and a specific surface area of 395 m2/m3·d were obtained once the filter was packed by using a grain size of 8.2 mm. The performance of the system, operated as a biological filter, was evaluated under an average organic load of 2.6±0.4 kgCODT/m3·d (6.7±1.1 gCODT/m2·d) without primary and secondary settling. The average CODT decreased from 220 mg/l in the influent to 88 mg/l in the effluent and the CODD was decreased from 148 mg/l in the influent to 50 mg/l in the effluent. The filter media, in combination with the biofilm, allowed a 75 % TSS removal. The ammonia nitrogen decreased from 51 mg/l in the influent to 33 mg/l in the effluent. The maximum flux coefficients of 9.3gCODdissolved/m2·d and 2.9gNH4-N/m2·d at the biofilm surface were used to simulate, with the Michaelis-Menten model, the profiles of dissolved COD, ammonium and nitrates through the aerated filter. It was possible to conclude that the backwashing procedure removed the excess biomass and was responsible for a homogeneous distribution of heterotrophic and autotrophic microorganisms along the filter depth.

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Application of low-cost algal nitrogen source feeding in fuel ethanol production using high gravity sweet potato medium

Journal of Biotechnology ◽

10.1016/j.jbiotec.2012.02.008 ◽

2012 ◽

Vol 160 (3-4) ◽

pp. 229-235 ◽

Cited By ~ 13

Author(s):

Yu Shen ◽

Jin-Song Guo ◽

You-Peng Chen ◽

Hai-Dong Zhang ◽

Xu-Xu Zheng ◽

...

Keyword(s):

Ethanol Production ◽

Nitrogen Source ◽

Sweet Potato ◽

Low Cost ◽

Fuel Ethanol ◽

High Gravity

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Tilapia rearing with high rate algal pond effluent: ammonia surface loading rates and stocking densities effects

Water Science & Technology ◽

10.2166/wst.2018.285 ◽

2018 ◽

Vol 78 (1) ◽

pp. 49-56

Author(s):

I. A. Sánchez ◽

R. K. X. Bastos ◽

E. A. T. Lana

Keyword(s):

Weight Gain ◽

Oxygen Demand ◽

Pilot Scale ◽

Ammonia Nitrogen ◽

High Rate ◽

Surface Loading ◽

Loading Rates ◽

Total Weight Gain ◽

Low Weight ◽

Total Ammonia

Abstract In two pilot-scale experiments, fingerlings and juvenile of tilapia were reared in high rate algal pond (HRAP) effluent. The combination of three different total ammonia nitrogen (TAN) surface loading rates (SLR1 = 0.6, SLR2 = 1.2; SLR3 = 2.4 kg TAN·ha−1·d−1) and two fish stocking densities (D1 = 4 and D2 = 8 fish per tank) was evaluated during two 12-week experiments. Fingerlings total weight gain varied from 4.9 to 18.9 g, with the highest value (equivalent to 0.225 g·d−1) being recorded in SLR2-D1 treatment; however, high mortality (up to 67%) was recorded, probably due to sensitivity to ammonia and wide daily temperature variations. At lower water temperatures, juvenile tilapia showed no mortality, but very low weight gain. The fish rearing tanks worked as wastewater polishing units, adding the following approximate average removal figures on top of those achieved at the HRAP: 63% of total Kjeldahl nitrogen; 54% of ammonia nitrogen; 42% of total phosphorus; 37% of chemical oxygen demand; 1.1 log units of Escherichia coli.

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Novel biofilm reactor for denitrification of municipal wastewater

Water Science & Technology ◽

10.2166/wst.2018.433 ◽

2018 ◽

Vol 78 (7) ◽

pp. 1566-1575 ◽

Cited By ~ 3

Author(s):

S. S. Rathnaweera ◽

B. Rusten ◽

K. Korczyk ◽

B. Helland ◽

E. Rismyhr

Keyword(s):

Carbon Source ◽

Municipal Wastewater ◽

Low Cost ◽

Oxygen Demand ◽

Pilot Scale ◽

Biofilm Reactor ◽

Treated Wastewater ◽

Removal Rates ◽

Good Filter ◽

Solids Removal

Abstract A pilot-scale CFIC® (continuous flow intermittent cleaning) reactor was run in anoxic conditions to study denitrification of wastewater. The CFIC process has already proven its capabilities for biological oxygen demand removal with a small footprint, less energy consumption and low cost. The present study focused on the applicability for denitrification. Both pre-denitrification (pre-DN) and post-denitrification (post-DN) were tested. A mixture of primary treated wastewater and nitrified wastewater was used for pre-DN and nitrified wastewater with ethanol as a carbon source was used for post-DN. The pre-DN process was carbon limited and removal rates of only 0.16 to 0.74 g NOx-N/m²-d were obtained. With post-DN and an external carbon source, 0.68 to 2.2 g NO3-Neq/m²-d removal rates were obtained. The carrier bed functioned as a good filter for both the larger particles coming with influent water and the bio-solids produced in the reactor. Total suspended solids removal in the reactor varied from 20% to 78% (average 45%) during post-DN testing period and 9% to 70% (average 29%) for pre-DN. The results showed that the forward flow washing improves both the DN function and filtration ability of the reactor.

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Pollutant removal from municipal sewage by a microaerobic up-flow oxidation ditch coupled with micro-electrolysis

Royal Society Open Science ◽

10.1098/rsos.201887 ◽

2021 ◽

Vol 8 (12) ◽

Author(s):

Zhen-dong Zhao ◽

Qiang Lin ◽

Yang Zhou ◽

Yu-hong Feng ◽

Qi-mei Huang ◽

...

Keyword(s):

Municipal Wastewater ◽

Low Cost ◽

Oxygen Demand ◽

Ammonia Nitrogen ◽

Influential Factors ◽

Pollutant Removal ◽

Municipal Sewage ◽

Reflux Ratio ◽

Oxidation Ditch ◽

Important Challenge

The development of efficient and low-cost wastewater treatment processes remains an important challenge. A microaerobic up-flow oxidation ditch (UOD) with micro-electrolysis by waterfall aeration was designed for treating real municipal wastewater. The effects of influential factors such as up-flow rate, waterfall height, reflux ratio, number of stages and iron dosing on pollutant removal were fully investigated, and the optimum conditions were obtained. The elimination efficiencies of chemical oxygen demand (COD), ammonia nitrogen (NH 4 + -N), total nitrogen (TN) and total phosphorus (TP) reached up to 84.33 ± 2.48%, 99.91 ± 0.09%, 93.63 ± 0.60% and 89.27 ± 1.40%, respectively, while the effluent concentrations of COD, NH 4 + -N, TN and TP were 20.67 ± 2.85, 0.02 ± 0.02, 1.39 ± 0.09 and 0.27 ± 0.02 mg l −1 , respectively. Phosphorous removal was achieved by iron–carbon micro-electrolysis to form an insoluble ferric phosphate precipitate. The microbial community structure indicated that carbon and nitrogen were removed via multiple mechanisms, possibly including nitrification, partial nitrification, denitrification and anammox in the UOD.

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