Energy and pressure requirements for compression of swine solid fraction compost

The excessive amount of pig slurry spread on soil has contributed to nitrate water pollution both in surface and in ground waters, especially in areas classified as vulnerable zones to nitrate in accordance with European Regulation (91/676/CEE). Several techniques have been developed to manage livestock slurries as cheaply and conveniently as possible and to reduce potential risks of environmental pollution. Among these techniques, solid-liquid separation of slurry is a common practice in Italy. The liquid fraction can be used for irrigation and the solid fraction, after aerobic stabilization, produces an organic compost rich in humic substances. However, compost derived from swine solid fraction is a low density material (bulk density less than 500 kg􀀀m–3). This makes it costly to transport composted swine solid fraction from production sites to areas where it could be effectively utilized for value-added applications such as in soil fertilization. Densification is one possible way to enhance the storage and transportation of the compost. This study therefore investigates the effect of pressure (20- 110 MPa) and pressure application time (5-120 s) on the compaction characteristics of compost derived from swine solid fraction. Two different types of material have been used: composted swine solid fraction derived from mechanical separation and compost obtained by mixing the first material with wood chips. Results obtained showed that both the pressure applied and the pressure application time significantly affect the density of the compacted samples; while the specific compression energy is significantly affected only by the pressure. Best predictor equations were developed to predict compact density and the specific compression energy required by the densification process. The specific compression energy values based on the results from this study (6-32 kJ􀀀kg–1) were significantly lower than the specific energy required to manufacture pellets from biomass feedstock (typically 19-90 kJ􀀀kg–1).

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Nitrogen fertilizer value of animal slurries with different proportions of liquid and solid fractions: A 3-year study under field conditions

The Journal of Agricultural Science ◽

10.1017/s0021859621000083 ◽

2021 ◽

pp. 1-11

Author(s):

Betina Nørgaard Pedersen ◽

Bent T. Christensen ◽

Luca Bechini ◽

Daniele Cavalli ◽

Jørgen Eriksen ◽

...

Keyword(s):

Solid Fraction ◽

Liquid Fraction ◽

N Fertilizer ◽

Organic N ◽

First Year ◽

Net N Mineralization ◽

Pig Slurry ◽

Total N ◽

Plant Availability ◽

Loamy Sand Soil

Abstract The plant availability of manure nitrogen (N) is influenced by manure composition in the year of application whereas some studies indicate that the legacy effect in following years is independent of the composition. The plant availability of N in pig and cattle slurries with variable contents of particulate matter was determined in a 3-year field study. We separated cattle and a pig slurry into liquid and solid fractions by centrifugation. Slurry mixtures with varying proportions of solid and liquid fraction were applied to a loamy sand soil at similar NH4+-N rates in the first year. Yields and N offtake of spring barley and undersown perennial ryegrass were compared to plots receiving mineral N fertilizer. The first year N fertilizer replacement value (NFRV) of total N in slurry mixtures decreased with increasing proportion of solid fraction. The second and third season NFRV averaged 6.5% and 3.8% of total N, respectively, for cattle slurries, and 18% and 7.5% for pig slurries and was not related to the proportion of solid fraction. The estimated net N mineralization of residual organic N increased nearly linearly with growing degree days (GDD) with a rate of 0.0058%/GDD for cattle and 0.0116%/GDD for pig slurries at 2000–5000 GDD after application. In conclusion NFRV of slurry decreased with increasing proportion of solid fraction in the first year. In the second year, NFRV of pig slurry N was significantly higher than that of cattle slurry N and unaffected by proportion between solid and liquid fraction.

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On-farm treatment of swine manure based on solid–liquid separation and biological nitrification–denitrification of the liquid fraction

Journal of Environmental Management ◽

10.1016/j.jenvman.2013.10.014 ◽

2014 ◽

Vol 132 ◽

pp. 87-93 ◽

Cited By ~ 36

Author(s):

B. Riaño ◽

M.C. García-González

Keyword(s):

Liquid Fraction ◽

Swine Manure ◽

Liquid Separation ◽

Biological Nitrification ◽

Solid Liquid ◽

Solid Liquid Separation ◽

On Farm

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Structured bottom section in inclined settlers for efficient continuous solid-liquid separation and washing of the solid fraction

Separation and Purification Technology ◽

10.1016/j.seppur.2020.118142 ◽

2021 ◽

Vol 259 ◽

pp. 118142

Author(s):

Nikolaus Hammerschmidt ◽

Hannah Engelmaier ◽

Christoph Dattenböck ◽

Jure Sencar ◽

Alois Jungbauer

Keyword(s):

Solid Fraction ◽

Liquid Separation ◽

Bottom Section ◽

Solid Liquid ◽

Solid Liquid Separation

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Concentration of Organic Acid from Fermented Food Wastes Using a MF/RO Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.569.281 ◽

2008 ◽

Vol 569 ◽

pp. 281-284 ◽

Cited By ~ 1

Author(s):

Jin Woo Lee ◽

Jong Oh Kim ◽

Jong Tae Jung

Keyword(s):

Organic Acid ◽

Food Waste ◽

Fermentation Broth ◽

Value Added ◽

Chloride Ion ◽

Fermented Food ◽

Ion Concentration ◽

Food Wastes ◽

Solid Liquid ◽

Solid Liquid Separation

The amount of food waste has been increasing every year. Food waste takes relativity high portion of domestic waste and we have much difficulty in treating it. Most of food wastes are landfilled or incinerated after drying for the reduction of water content. The operation cost of the landfill and the incineration are very high. To solve the landfill and the incineration problems in recent years, the recycling of food waste was used by the methods of turning food waste into animal food and fertilizer. Food wastes are compatible to be used as feedstock of the fermentation because they contain valuable nutrients. Among these situations, organic acids, which are effectively used in a variety of industrial processes, can be considered to be a high cost value-added products. The purpose of this study is to evaluate the possibility of organic acid concentration using a MF/RO system. A MF/RO system was believed to be an effective one for the concentration of organic acid from food waste. Water quality of fermentation broth, MF permeate and RO retentate in terms of conductivity, pH, electric conductivity, TS (Total solids), TDS (Total dissolved solids), CODcr concentration, chloride ion concentration was examined as analytic items. pH of fermentation broth was higher than that of MF permeate and RO retentate due to the concentration of organic acid. pH of RO retentate was about 4. Conductivity, TDS, CODCr and chloride ion of RO retentate were about 1.3, 1.3, 2.9, 4.5 times higher than that of fermentation broth, respectively and TS reduced about 0.8 times. This may be ascribed to separate effectively the solid-liquid separation by MF and RO rejection. Consequently, a MF/RO system is believed to be applicable for the concentration of organic acid from fermentation broth of food waste.

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Effect of acidification on solid–liquid separation of pig slurry

Biosystems Engineering ◽

10.1016/j.biosystemseng.2015.11.004 ◽

2016 ◽

Vol 143 ◽

pp. 20-27 ◽

Cited By ~ 6

Author(s):

Giorgia Cocolo ◽

Maibritt Hjorth ◽

Agata Zarebska ◽

Giorgio Provolo

Keyword(s):

Pig Slurry ◽

Liquid Separation ◽

Solid Liquid ◽

Solid Liquid Separation

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Chemically Enhanced Solid–Liquid Separation of Digestate: Suspended Solids Removal and Effects on Environmental Quality of Separated Fractions

Waste and Biomass Valorization ◽

10.1007/s12649-021-01591-y ◽

2021 ◽

Author(s):

Giovanni Beggio ◽

Wei Peng ◽

Fan Lü ◽

Andrea Cerasaro ◽

Tiziano Bonato ◽

...

Keyword(s):

Environmental Quality ◽

Solid Fraction ◽

Total Suspended Solid ◽

Complete Removal ◽

Liquid Separation ◽

Polyaluminum Chloride ◽

Water Extracts ◽

Solid Liquid ◽

Solid Liquid Separation

AbstractChemically enhanced solid–liquid separation (CES) of digestate can improve its membrane filterability but potentially influence the environmental features of the separated solid fraction, thus hindering its possible agricultural reuse. In this study, the effects were assessed of different dosages of polyaluminum chloride (PAC), epichlorohydrine-dimethylamine with ethylendiamine (DEED) and polyacrilamides (PAM) on CES of digestate from biowaste in terms of Total Suspended Solid (TSS) mitigation in the liquid fractions and resulting environmental quality of the solid fractions. Results from lab-scale trials showed that applied chemicals significantly increased the centrifugation efficiency with achieving minimum TSS concentration of 2347 ± 281 mgTSS/L (up to 90% improved TSS mitigation). Also, performed treatments led to almost complete removal of P and Heavy Metals (HMs) from the liquid fractions after centrifugation. Conditioned solid fractions showed higher Al (reaching 20 g kg−1 TS), organic carbon and nitrogen content (up to 324 mgTOC kg−1 TS and 44.1 mgTKN kg−1 TS, respectively) due to residual PAC, DEED and PAM. However, achieved concentrations of HMs guaranteed full consistency with EU regulation limits established for agricultural reuse of organic soil amendments. Further, leaching tests performed on the treated solid fractions indicate higher chlorides and soluble Al concentrations in the water extracts (up to 4.6 g L−1 and 2.3 g L−1, respectively), but lower HMs leachability from the digestates undergone CES. Nevertheless, water extracts from treated biosolids were characterized by higher phytotoxicity, likely related with direct Al toxicity and increased salinity due to chemicals addition. Accordingly, the effects on soil–plant system should be better investigated when agricultural reuse of CES-treated solid fraction of digestate is foreseen. Graphic abstract

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Persistence and Leaching Potential of Microorganisms and Mineral N in Animal Manure Applied to Intact Soil Columns

Applied and Environmental Microbiology ◽

10.1128/aem.02506-12 ◽

2012 ◽

Vol 79 (2) ◽

pp. 535-542 ◽

Cited By ~ 26

Author(s):

M. G. Mostofa Amin ◽

Anita Forslund ◽

Xuan Thanh Bui ◽

René K. Juhler ◽

Søren O. Petersen ◽

...

Keyword(s):

Liquid Fraction ◽

Animal Manure ◽

Soil Columns ◽

Leaching Potential ◽

Content Type ◽

E Coli ◽

Subsurface Injection ◽

Solid Liquid ◽

Solid Liquid Separation ◽

Intact Soil

ABSTRACTPathogens may reach agricultural soils through application of animal manure and thereby pose a risk of contaminating crops as well as surface and groundwater. Treatment and handling of manure for improved nutrient and odor management may also influence the amount and fate of manure-borne pathogens in the soil. A study was conducted to investigate the leaching potentials of a phage (Salmonella entericaserovar Typhimurium bacteriophage 28B) and two bacteria,Escherichia coliandEnterococcusspecies, in a liquid fraction of raw pig slurry obtained by solid-liquid separation of this slurry and in this liquid fraction after ozonation, when applied to intact soil columns by subsurface injection. We also compared leaching potentials of surface-applied and subsurface-injected raw slurry. The columns were exposed to irrigation events (3.5-h period at 10 mm h−1) after 1, 2, 3, and 4 weeks of incubation with collection of leachate. By the end of incubation, the distribution and survival of microorganisms in the soil of each treatment and in nonirrigated columns with injected raw slurry or liquid fraction were determined.E. coliin the leachates was quantified by both plate counts and quantitative PCR (qPCR) to assess the proportions of culturable and nonculturable (viable and nonviable) cells. Solid-liquid separation of slurry increased the redistribution in soil of contaminants in the liquid fraction compared to raw slurry, and the percent recovery ofE. coliandEnterococcusspecies was higher for the liquid fraction than for raw slurry after the four leaching events. The liquid fraction also resulted in more leaching of all contaminants exceptEnterococcusspecies than did raw slurry. Ozonation reducedE. colileaching only. Injection enhanced the leaching potential of the microorganisms investigated compared to surface application, probably because of a better survival with subsurface injection and a shorter leaching path.

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