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Many factors affect the volume of biogas production in the anaerobic digestion of plant and animal wastes. In this treatise the three major factors of temperature, pressure and PH are investigated. Here the biodegradable wastes used were Cassava peelings and cow dungs, Beans waste and cow dungs, Cassava peelings and beans wastes. For the purpose of this investigation, a 100 liters capacity steel biogas digester was constructed to investigate these factors. A batch operation method was used whereby a daily biogas generation was monitored for 24 consecutive days. It is pertinent to state here that other factors that could affect the volume of biogas production like alkalinity, acidity etc were ignored. Cassava peelings and cow dungs produced the highest biogas of 0.032m2/kg/day at a pH value of 7.34, followed by beans waste and cow dungs mixture and lastly Cassava peelings and beans waste having the least volume. The respective effects of temperature, pressure and PH were monitored and plotted alongside these biogas productions to showcase their effects. From the plots, their respective effects on the respective volumes of biogas generated can easily be seen. It is important to note in the passing that biogas is a form of renewable energy. [ABSTRACT FROM AUTHOR]

The development of livestock waste biogas technology as an alternative energy source can solve the problem of energy supply and solve the problem of livestock waste contamination to the environment. The utilization of biogas requires community participation, especially in filling and maintaining the digester. This study aims to analyze the level of community participation in biogas and analyze the factors that influence it. This research was conducted in Boyolali Regency, considering that the cattle population in this district is very high, namely 86,363 dairy cows and 86,988 beef cattle, so that the potential for biogas raw materials is high. Respondents of the study were 60 people who used livestock waste biogas. The research method used is descriptive quantitative, with survey data collection techniques, and the data were analyzed descriptively and multiple linear regression test. The results showed that community participation in biogas development began at the planning, implementation, or construction stages of biogas installations and the use of biogas as an energy source. The most significant community participation was at the consultation level (36%). The results of the multiple linear regression test obtained the value of the equation Y=1,835+0,092X1+0,083X2-0,006X3+0,078X4+0,024X5. The results of the F test show that the value of Fcount>Ftable (3.38 > 2.89) means that the variables of education, number of livestock, income, experience, and intensity of counseling together affect participation. In contrast, the results of the t-test show that the variable partially influences the participation number of livestock, income, and power of extension. This study concludes that the most significant community participation in the use of biogas is in consultation, and community participation can be increased through increasing the number of livestock as biogas raw material providers and assistance through counseling activities. [ABSTRACT FROM AUTHOR]

Antibiotics are widely used in animal husbandry, and various types of antibiotic resistance genes (ARGs) are frequently detected in livestock waste around the world. Conventional livestock waste treatment processes do not completely remove ARGs, resulting in their release to soil and water environments. Various exposure routes of these ARGs to humans, including inhalation and ingestion of antibiotic-resistant bacteria (ARB) that harbor them, may be contributing to the rise in resistant clinical infections that are increasingly difficult to treat with antibiotics. In this review, we assess the occurrence and variability of ARGs in livestock wastes and their potential propagation pathways to human pathogens. We also review the mechanisms and environmental factors that influence the dissemination of ARGs through these pathways, and evaluate the ARG removal efficiency of common livestock waste management approaches. Challenges and research needs for assessing and mitigating the risk of antibiotic resistance dissemination from livestock waste are also presented. [ABSTRACT FROM AUTHOR]

Healthy soils are essential for progressive agronomic activities. Organic fertilization positively affects agro-ecosystems by stimulating plant growth, enhancing crop productivity and fruit quality and improving soil fertility. Soil health and food security are the key elements of Organic Agriculture 3.0. Landfilling and/or open-dumping of animal wastes produced from slaughtering cause environmental pollution by releasing toxic substances, leachate and greenhouse gases. Direct application of animal carcasses to agricultural fields can adversely affect soil microbiota. Effective waste management technologies such as thermal drying, composting, vermicomposting and anaerobic digestion transform animal wastes, making them suitable for soil application by supplying soil high in organic carbon and total nitrogen. Recent agronomic practices applied recycled animal wastes as organic fertilizer in crop production. However, plants may not survive at a high fertilization rate due to the presence of labile carbon fraction in animal wastes. Therefore, dose calculation and determination of fertilizer application frequency are crucial for agronomists. Long-term animal waste-derived organic supplementation promotes copiotrophic microbial abundance due to enhanced substrate affinity, provides micronutrients to soils and protects crops from soil-borne pathogens owing to formation of plant-beneficial microbial consortia. Animal waste-derived organically fertilized soils possess higher urease and acid phosphatase activities. Furthermore, waste to fertilizer conversion is a low-energy requiring process that promotes circular bio-economy. Thus, considering the promotion of soil fertility, microbial abundance, disease protection and economic considerations application of animal-waste-derived organic fertilizer should be the mainstay for sustainable agriculture.

Authors discuss actual state in the area of waste management in the Slovak Republic in the light of achieving recycling targets and obligations arising from the legislation of the European Union. The article presents and explains current trends, policies and legislation in this area in the Slovak Republic with emphasis on introducing the new piece of legislation - Act No. 329/2018 Coll. on fees for the waste landfilling. [ABSTRACT FROM AUTHOR]

Poultry litter (PL) is a significant source of nutrients, but a suitable amount of carbon needs to be added as a bulking agent during its composting to a stable nutrient source. Here, we characterized the transformation of phosphorus and other plant nutrients during aerobic composting of PL with sugarcane (SW) and cabbage waste (CW) for 120 d. Periodic samples were collected during composting and analyzed for total C, P (and its fractions), K, Ca, Mg, Cu, Fe, Zn, Mn, EC and pH. At the initial stage of composting (20 d), the P fractions varied in the order: water soluble P > NaHCO3-P (readily plant-available) > HCl-P (Ca+Mg-bound) > residual-P > NaOH-P (Fe+Al-bound). After 120 d, the order was HCl-P > residual-P > water-P > NaHCO3-P > NaOH-P. These variations suggested a transformation of labile Pi to more recalcitrant forms during composting. Water soluble P was the dominant fraction during the initial composting period. This declined progressively with time of composting, while the HCl-P increased, confirming the transformation of the more vulnerable water soluble P to the more recalcitrant HCl-extractable P. This indicated that the composting could be a useful way of managing manure for P stabilization and reducing its losses in runoff water following land application. The total C varied directly with the ratio of sugarcane and cabbage wastes in the manure but was inversely related to the duration of composting. Extractable K, Ca, Mg, and Na increased whereas trace elements concentrations decreased with time of composting. The higher availability of basic plant nutrients and reduced availability of heavy metals in the mature compost are valuable attributes for safe use in sustainable agricultural production. [ABSTRACT FROM AUTHOR]

Summary: Changes in climate due to the enormous amount of carbon dioxide emissions have really encouraged the development of energy sources that are renewable, sustainable, and eco‐friendly. The development of alternative energy sources can also be attributed to the rapid decrease in resources of fossil energy. Biodiesel has gained significant interest in recent years due to its fossil fuel–like properties and sustainable and eco‐friendly characteristics. However, most biodiesels are expensive because of the high cost of feedstock largely based on edible vegetable oil sources. The use of animal fats waste as cost effective feedstock in biodiesel production has gained considerable attention in recent years. Although, most studies regarding the use of animal wastes as feedstock in biodiesel production are still in the early stages, the advantages of this type of feedstock have been highlighted in the literature. However, most studies have not focus on the recent advances in the use of animal fats waste. The studies on the use of novel approach have been reported in isolation. Therefore, this current study attempts to highlight recent developments of the most commonly used animal fats waste in the production of biodiesel. In addition, emphasis was given to the most appropriate production technique, catalyst, energy requirement, and optimum reaction conditions. [ABSTRACT FROM AUTHOR]

Aerobic composting is used widely for animal manure recycling, and it may reduce the amount of antibiotic resistance genes (ARGs) that enter the environment. We sampled three types of animal (bovine, chicken, and pig) manure and the corresponding composts from 12 large-scale farms, and tested multiple ARGs and mobile genetic elements (MGEs) by high-throughput qPCR. A total of 109 ARGs were detected in the manure and compost samples, thereby demonstrating that both are important ARG reservoirs. The diversity and abundance of ARGs were significantly higher in chicken and pig manure than bovine manure, but industrial composting was more efficient at reducing the ARGs in chicken manure than pig and bovine manure. Composting universally reduced some ARGs, but inconsistently influenced other ARGs from different types of animal manures. Network analysis detected the widespread co-occurrence of ARGs and MGEs. floR , ermF , catB3 , aac ( 6′ ) -lb ( akaaacA4 ), and aadA were identified as suitable indicator genes for estimating the total abundance of ARGs. Our results suggest that different animal species had significant effects on the diversity, abundance, and persistence of ARGs, where the abundance of transposons, heavy metal concentration, total nitrogen level, and the dosage and duration of exposure to antibiotics may explain these differences. [ABSTRACT FROM AUTHOR]

BACKGROUND This study investigated the use of a novel start-up strategy to obtain nitrogen removal via nitrite using real-time aeration control, in a sequencing batch reactor (SBR1), for the treatment of slaughterhouse wastewater. In addition, another SBR (SBR2) was operated with the same objective, but with a start-up from seed sludge. Furthermore, analysis of the nitrous oxide (N2O) production and emission was conducted for different nitritation levels. RESULTS Through the absence of an inoculum in SBR1, the nitrifying population could be regulated from the beginning. Beceause of this, nitrite oxidising bacteria could be prevented. This was proved by the nitritation degree (ND) which was already above 80% from day 28, although it took 59 days to achieve sufficient nitrogen removal efficiency (> 80%). In contrast for SBR2, it took 90-110 days to achieve full nitritation, however the nitrogen removal efficiency was above 90% at all times. The maximum N2O emission resulted to be 0.12% of the nitrogen load. CONCLUSION This study suggested the importance of seeding sludge for the achievement of full nitritation. Moreover, a strong positive relationship between the ND and N2O emission was observed. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The importance of renewable energy usage is increasing gradually due to the reasons of energy supplying security, environmental pollution and reducing dependency on external sources in all over the world as also same in Turkey. Biomass is a clean and sustainable energy source that can be produced from various kind of organic waste. Turkey has considerable biomass energy potential, and about 6% of the total potential is located in the eastern region. Ardahan is one of the eastern cities of the country whose economy mainly relies on livestock farming. This paper presents biogas energy potential from animal manure and agricultural residue and corresponding CO 2 emission reduction in Ardahan. Calculations were made according to the analysis of the animal manure and the agricultural crop quantities of 2015 data considering of the biochemical methane potential (BMP), availability factors, volatile solid ratio of the manure, harvested area and unit methane potential of cereals. The total electricity production potential of the evaluated biomass sources is 323 GWh/year. The total CO 2 emission reduction is about 2 million tons/year in the case of biogas combustion power plant exists instead of coal fired power plants. [ABSTRACT FROM AUTHOR]

This study aims to investigate the effects of the organic loading rate (OLR) and the aeration rate on denitrifying phosphate removal (DPR) from slaughterhouse wastewater treated at a temperature of 11 °C. Three laboratory-scale intermittently aerated sequencing batch reactors (IASBRs) were set up and three OLRs and five aeration rates were employed in the study. The results indicated that efficient removals of nitrogen (N) and phosphorus (P) from DPR were achieved. Furthermore, the intermittent aeration pattern benefitted both the phosphorus-accumulating organisms (PAOs) and the denitrifying phosphorus-accumulating organisms (DPAOs) that accumulated at 11 °C. The ratio of P uptake in the aeration periods/P release in the non-aeration periods was in the range of 0.94-1.10 in the three stages. The relationship between the specific poly-β-hydroxybutyrate (PHB) degradation rate (z), the specific P removal rate (x), and the specific total oxidized nitrogen (TON) reduction rate (y) can be fitted approximately as a plane (z = 1.3626x+0.2882y-0.6722, R² = 0.83). [ABSTRACT FROM AUTHOR]

Animal manure waste is considered as an environmental challenge especially in farming areas mainly because of gaseous emission and water pollution. Among all the pollutants emitted from manure waste, ammonia is of greatest concern as it could contribute to formation of aerosols in the air and could hardly be controlled by traditional disposal methods like landfill or composting. On the other hand, manure waste is also a renewable source for energy production. In this work, an environmental friendly animal waste disposal process with combined ammonia recovery and energy production was proposed and investigated both experimentally and economically. Lab-scale feasibility study results showed that 70% of ammonia in the manure waste could be converted to struvite as fertilizer, while solid manure waste was successfully gasified in a 10 kW downdraft fixed-bed gasifier producing syngas with the higher heating value of 4.9 MJ/(N m 3 ). Based on experimental results, economic study for the system was carried out using a cost-benefit analysis to investigate the financial feasibility based on a Singapore case study. In addition, for comparison, schemes of gasification without ammonia removal and incineration were also studied for manure waste disposal. The results showed that the proposed gasification-based manure waste treatment process integrated with ammonia recovery was most financially viable. [ABSTRACT FROM AUTHOR]

We report here a novel synergistic catalysis system combined with porous organic polymeric solid acid (H-PDVB-SO3H) and K2O doped porous γ-Al2O3 solid base (γ-Al2O3-K2O). H-PDVB-SO3H and γ-Al2O3-K2O have abundant nanopores, controllable surface wettability, and high concentrations of acidic and basic sites. The synergistic catalysis system exploited by us could efficiently transform acidulated bone oil and plant oil into high quality biodiesel under mild conditions, which achieved ASTM specifications pertaining to acid number and total and free glycerin. Acidulated bone is a bone meal treated with sulfuric acid containing high-value hydrocarbons, which is generated in large amounts by the cattle industry. This work develops an efficient and cost-effective approach to transform animal waste into high quality biodiesel. [ABSTRACT FROM AUTHOR]

The need to meet rapidly increasing demands for synthetic nitrogen (N) while reducing dependence on fossil fuels has been driving widespread attention to the recuperation and reuse of nutrients present in digestate and animal manure. The N release and mineralization potential of animal manure ( AM), digestate ( DIG), liquid fraction of digestate ( LFDIG) and mineral concentrate ( MC) were assessed in comparison with N availability from calcium ammonium nitrate ( CAN) as a reference. The release was highly dependent on the product [ABSTRACT FROM AUTHOR]

The South African poultry industry has grown exponentially in recent years due to an increased demand for their products. As a result, poultry plants consume large volumes of high quality water to ensure that hygienically safe poultry products are produced. Furthermore, poultry industries generate high strength wastewater, which can be treated successfully at low cost using anaerobic digesters. In this study, the performance of a bench-scale mesophilic static granular bed reactor (SGBR) containing fully anaerobic granules coupled with an ultrafiltration (UF) membrane system, as a post-treatment system, was investigated. The poultry slaughterhouse wastewater was characterized by a chemical oxygen demand (COD) range between 1,223 and 9,695 mg/L, average biological oxygen demand of 2,375 mg/L and average fats, oil and grease (FOG) of 554 mg/L. The SGBR anaerobic reactor was operated for 9 weeks at different hydraulic retention times (HRTs), i.e. 55 and 40 h, with an average organic loading rate (OLR) of 1.01 and 3.14 g COD/L.day. The SGBR results showed an average COD, total suspended solids (TSS) and FOG removal of 93%, 95% and 90% respectively, for both OLR. The UF post-treatment results showed an average of COD, TSS and FOG removal of 64%, 88% and 48%, respectively. The overall COD, TSS and FOG removal of the system (SGBR and UF membrane) was 98%, 99.8%, and 92.4%, respectively. The results of the combined SGBR reactor coupled with the UF membrane showed a potential to ensure environmentally friendly treatment of poultry slaughterhouse wastewater. [ABSTRACT FROM AUTHOR]

The establishment of a reliable index is an essential need to assess the degree of stability and maturity of solid wastes vermicomposts. The objective of this study was to investigate the effects of vermicomposting process on some chemical (pH, EC, OC, TN, lignin and C:N ratio) and biochemical properties of the cow manure (CM) and wheat residue (WR). Results demonstrated that during vermicomposting process of CM and WR urease activity was highly correlated with the time of vermicomposting (r = −0.97 ∗∗ for CM and r = −0.99 ∗∗ for WR), and well able to show the stability of organic waste. The urease activity showed significant correlations with the C:N ratio during the vermicomposting of CM and WR (r = 0.89 ∗ and r = 0.93 ∗∗ respectively) therefore it can be considered as a reliable indicator for determining the maturity and stability of organic wastes during vermicomposting process. [ABSTRACT FROM AUTHOR]

Disposal of animal manure without treatment can be harmful to the environment. In this study, samples of four zoo animal dungs and one horse dung were pre-composted in two ways: (a) traditional composting and (b) bokashi pre-composting for 1 month, followed by vermicomposting for 3 months. The permanence (PEf) and reproductive potential (RP) of Eisenia foetida as well as the quality of vermicompost were evaluated. The PEf values and RP index of E. foetida were higher for samples pre-composted using the traditional composting method (98.7–88% and 31.85–16.27%, respectively) followed by vermicomposting (92.7–72.7% and 22.96–13.51%, respectively), when compared with those for bokashi pre-composted samples followed by vermicomposting, except for the horse dung sample (100% for both the parameters). The values of electrical conductivity (EC), cation exchange capacity (CEC), organic C, total N, available P, C/N ratio, and pH showed that both treatments achieved the norms of vermicompost (<4 mS cm −1 , 40 cmol kg −1 , 20–50%, 1–4%, ≤20, 5.5–8.5, respectively). However, the maturity indices of vermicompost, namely, organic matter loss, N loss, and CEC/organic carbon (OC) ratio indicated that bokashi pre-composting followed by vermicomposting produced the highest values (98.7–70.7%, 97.67–96.65%, and 2.7–1.97%, respectively), when compared with the other method adapted in this study. Nevertheless, further studies with plants for plant growth evaluation are needed to assess the benefits and limitations of these two pre-composting methods prior to vermicomposting. [ABSTRACT FROM AUTHOR]

A nationwide survey of animal manure-based composts was carried out in China. Two hundred and twelve samples were collected and analyzed for the concentrations of 9 heavy metals or metalloids and arsenic (As) speciation. The concentrations of heavy metals vary widely (Zn 11.8–3692, Cu 3.6–916, Cr 0.7–6603, Ni 0.7–73, Pb 0.05–189, As 0.4–72, Co 0.1–94, Cd 0.01–8.7 and Hg 0.01–1.9 mg kg −1 dry weight). Compared with the maximum permissible values of the Chinese standard for organic fertilizers, 13.7% and 2.4% of the composts exceeded the limits for As (15 mg kg −1 ) and Cd (3 mg kg −1 ), respectively. Some samples contained very high concentrations of Zn and Cu, although no limits have been set for these two metals in China. Further analysis showed that As was present mainly as arsenate (As Ⅴ ), with dimethylarsenate (DMA) and monomethylarsenate (MMA) as the minor species in composts. There were significant correlations between the concentrations of Zn, Cu and As, suggesting co-contamination of these elements in some composts. Monte Carlo simulations based on the distributions of metal concentrations and application rate showed that repeated applications of compost likely increase the concentrations of Zn, Cu, Cd and Hg in soil significantly compared with the soil background levels. This study highlights a need to minimize the concentrations of Zn, Cu, Cd, Hg and As in animal manures to ensure their safe recycling to agricultural soils. [ABSTRACT FROM AUTHOR]

Anaerobic digestion (AD), which is a process for generating biogas, can be applied to the treatment of organic wastes. Owing to its smaller footprint, lower energy consumption, and less digestate, high solid anaerobic digestion (HSAD) has attracted increasing attention. However, its biogas production is poor. In order to improve biogas production and decrease energy consumption, an improved thermal treatment process was proposed. Raw swine manure (>20% solid content) without any dilution was thermally treated at 70 ± 1 °C for different retention times, and then its effect on HSAD was investigated via batch AD experiments at 8.9% solid content. Results showed that the main organic components of swine manure hydrolyzed significantly during the thermal treatment, and HSAD’s methane production rate was improved by up to 39.5%. Analysis using two kinetic models confirmed that the treatment could increase biodegradable organics (especially the readily biodegradable organics) in swine manure rather than upgrading its hydrolysis rate. It is worth noting that the superimposed first-order kinetics model was firstly applied in AD, and was a good tool to reveal the AD kinetics mechanism of substrates with complex components. [ABSTRACT FROM AUTHOR]

The study analyses dis-adoption of biogas technologies in Central Uganda. Biogas technology makes use of livestock waste, crop material and food waste to produce a flammable gas that can be used for cooking and lighting. Use of biogas technology has multiple benefits for the households since it reduces the need for fuelwood for cooking and also produces bio-slurry which is a valuable fertilizer. Despite efforts by Government and Non-Governmental Organizations to promote the biogas technology, the rate of its adoption of biogas technology was found to be low, estimated at 25.8% of its potential. A review of literature showed that the households that dis-adopted biogas technology, did so within a period of 4 years after its installation, yet the lifespan of using it is estimated at 25 years. There was need to examine the factors contributing to dis-adoption. Using cross sectional data collected from Luwero and Mpigi districts found in Central Uganda, a probit model was estimated. The findings showed that an increase in the family size, the number of cattle, number of pigs and the age of the household head reduced the likelihood of biogas technology dis-adoption. Other factors that contributed to dis-adoption included the failure to sustain cattle and pig production that are necessary for feedstock supply, reduced availability of family labor the and inability of the households to repair biogas digesters after malfunctioning. Based on the findings, it was concluded that long term use of biogas technology required improved management practices on the farm so as to sustain livestock production. It is also recommended that quality standards and socio-cultural factors be considered in the design of biogas digesters and end use devices. [ABSTRACT FROM AUTHOR]

Manure represents an exquisite mining opportunity for nutrient recovery (nitrogen and phosphorus), and for their reuse as renewable fertilisers. The ManureEcoMine proposes an integrated approach of technologies, operated in a pilot-scale installation treating swine manure (83.7%) and Ecofrit® (16.3%), a mix of vegetable residues. Thermophilic anaerobic digestion was performed for 150 days, the final organic loading rate was 4.6 kgCOD m-3 d-1, with a biogas production rate of 1.4 Nm3 m-3 d-1. The digester was coupled to an ammonia side-stream stripping column and a scrubbing unit for free ammonia inhibition reduction in the digester, and nitrogen recovery as ammonium sulphate. The stripped digestate was recirculated daily in the digester for 15 days (68% of the digester volume), increasing the gas production rate by 27%. Following a decanter centrifuge, the digestate liquid fraction was treated with an ultrafiltration membrane. The filtrate was fed into a struvite reactor, with a phosphorus recovery efficiency of 83% (as orthophosphate). Acidification of digestate could increment the soluble orthophosphate concentration up to four times, enhancing phosphorus enrichment in the liquid fraction and its recovery via struvite. A synergistic combination of manure processing steps was demonstrated to be technologically feasible to upgrade livestock waste into refined, concentrated fertilisers. [ABSTRACT FROM AUTHOR]

The growing number of biogas plants in Europe has resulted in increased production of nutrient-rich digestate with great potential as fertilizer for arable land. The nutrient composition of digestate varies with the substrate treated in the biogas plant and may contain compounds that stimulate or inhibit soil microbial activity. This study compared 20 digestates (D) with 10 pig slurries (PS) and 10 cow manures (CM) regarding their chemical content and their effect on soil microbial activities, i.e. potential ammonia oxidation rate (PAO) and soil respiration. The results showed no significant differences within the D group when divided based on substrate type. i.e. manure dominated vs. other organic waste materials in any of the tests. In general D contained significantly higher concentrations of ammonium while the concentrations of total carbon and volatile fatty acids were higher in PS and CM than in D. The D showed both stimulating and inhibiting effects on PAO, while all CM and all PS except one showed inhibiting effects on PAO. However, PAO activity was negatively correlated with the content of volatile fatty acids in the residues indicating that these compounds may be the cause of the inhibition. The maximum respiration activity ( h peakmax ) was lower and the time point for the maximum respiration activity ( t peakmax ) occurred earlier for D compared with CM and PS. This earlier peak time could be indicative of a high proportion of easily degradable carbon in D compared with PS and CM. However, the utilization rate of carbon, i.e. the proportion of added organic C converted to CO 2 -C during 12 days, did not differ significantly between D, PS and CM, indicating that overall carbon quality in the different fertilizers was still roughly comparable. In short, our results suggest that digestates were different compared with PS and CM but without posing a higher risk with respect to their impact on soil microbial activity. [ABSTRACT FROM AUTHOR]

Manure treatment becomes a focal issue in relation to current EU and national policies on environmental, climate and renewable energy matters. The objective of this desk study was to collect all available data on the treatment of manure from cattle, pig and poultry farms for an overview of manure treatment in France. Specific surveys in 2008 showed that 12% of pig farms, 11% of poultry farms and 7.5% of cattle farms was concerned by manure treatment. Taken together, the treatment of pig, poultry and cattle manure accounted for 13.6 million tons corresponding to 11.3% of the total annual tonnage (120 million tons). The main processes, mostly applied on the farm, were composting (8.5 million tons), aerobic treatment (2.9 million tons of pig slurry) and anaerobic digestion (1 million tons). Other manure treatments, including physical-chemical treatment, were less frequent (0.4 million of m 3 ). Treated manure was mainly used to fertilize the soil and crops on the farm concerned. Manure treatment can thus be considered to be underused in France. However, anaerobic digestion is expected to expand to reach the European target of 20% of energy from renewable sources. Nevertheless, this expansion will depend on overcoming the constraint requiring registration or normalization of the use of the digestate as fertilizer. Thus, to avoid penalizing farmers, the further development or creation of collective processing platforms is recommended, combined with an N recovery process that will enable the production of organic amendments and fertilizers in an easy marketable form. [ABSTRACT FROM AUTHOR]

Crops and livestock transform a general range of 20% to 50% of applied nitrogen (N) into product N (e.g., grain, forage, meat, milk). Most N not incorporated into agricultural products is lost to the environment. The objective of this study was to quantify soil N input (fertilizer N, biologically fixed-N) incorporation into the major diet components fed to dairy cows, diet component N secretions in milk N and excretion in manure N constituents, and manure N recycled back through the feed supply. Alfalfa for silage (AS), corn for silage (CS), corn grain (CG) and soybeans (SB, eventually solvent-extracted into soybean meal, SBM) were enriched in the field with fertilizers containing the stable isotope 15 N. Each 15 N-labeled diet component was fed individually to twelve mid-lactation cows (3 cows per 15 N-enriched diet component) as part of a total mixed ration (TMR). Proportions of each component’s 15 N intake ( 15 NI) recovered in milk, feces, fecal undigested dietary N, urine, urinary urea and retained by cows were determined during a 4-day 15 N feeding period and 4 days thereafter. Diet component 15 N manure was applied to field plots and 15 N uptake by corn for silage was determined over two succeeding years. The wide range in total 15 N recoveries (% 15 NI), greatest from cows fed AS (67) followed by CS (61), SBM (61) and CG (54) indicate significant differences in diet component 15 N retention by cows. Relative 15 N recoveries (% of total 15 N recovered) in milk were greater (and statistically similar) from cows fed CG and SBM (average of 29.2) than from cows fed AS and CS (also statistically similar, average of 18.4). Relative 15 N recoveries in feces were greater (and statistically similar) from cows fed AS and CS (average of 42.2) than from cows fed CG and SBM (also statistically similar, average of 30.7), and 15 N recoveries as fecal undigested dietary N were greatest from cows fed CG (2.5) followed by AS and CS (average of 2.2) and SBM (<1). Relative 15 N recoveries in urine (average of 39.7) and urinary urea (average 34.0) were similar across all diet components. Over the 2-year field study period, greatest manure 15 NUE (% of applied manure 15 N recovered as corn silage 15 N) was obtained in plots amended with manure 15 N derived from SBM (38.2) and lowest from CS (30.5). The greater total N use efficiency (percent N inputs incorporated into milk N plus corn silage N) for SBM (68.3) and AS (51.5) than for CG (47.4) and CS (40.6) can be attributed mostly to differences in N use efficiencies of the biologically-fixed-N and fertilizer N to grow diet components. A balance between corn, alfalfa and soybeans in dairy cropping systems should be encouraged to not only enhance N use efficiency in feed and milk production and manure N recycling, but also to capture many of the long-term benefits associated with corn-legume rotations. [ABSTRACT FROM AUTHOR]

The low cost and efficient CaO catalysts have been successfully prepared from chicken manure by a simple calcination, in this present work. Chicken manure contains significant content of calcium compounds that can easily be converted into the active calcium oxide catalyst after calcination at 850 °C under air. The Hammett indicator test showed that the obtained CaO catalyst has the basic strength in a range of 15 < H_ < 18.4, revealing that the basicity of the obtained catalyst is mainly ascribed to the strong basic properties of metal–O groups. The obtained CaO catalyst exhibited high catalytic activity for biodiesel production from transesterification of waste cooking oil and methanol. Up to 90% FAME yield was obtained at optimum reaction condition (i.e. 7.5 wt% of catalyst, 15:1 of methanol:oil molar ratio and 65 °C). The experimental kinetic data fitted well with the pseudo-first order model and the activation energy was found to be 78.8 kJ mol −1 . Moreover, fuel properties of the produced biodiesel were determined according to the European standard and found to be within the specifications. The uses of chicken manure as a catalyst source and waste cooking oil as a raw material for biodiesel production not only offers the environmentally friendly and cost-effective way to recycle those wastes, but also help to lower the biodiesel production cost to make biodiesel competitive with petroleum-based diesel. [ABSTRACT FROM AUTHOR]

The objective of this research was to analyze the overall performance, especially the removal efficiency, of the combined plug-flow anaerobic digester (PFAD) and upflow anaerobic sludge blanket (UASB) system, at a large swine farm in Thailand. Eighty-four wastewater samples from the digester were collected during the observation period of 302 days. Appropriate influent and effluent regions were selected for wastewater collection. Treatment efficiencies of the system were evaluated by key parameters such as chemical oxygen demand (COD), soluble chemical oxygen demand (SCOD), total solids (TS), total suspended solids (TSS) and total Kjeldahl nitrogen (TKN). In addition, microbiological parameters such as E. coli and Salmonella spp. were measured. These parameters were analyzed according to the Standard Method for Examination of Water and Wastewater. The average removal efficiencies of COD, SCOD, TS, TSS and TKN were 80.6%, 85.6%, 58.7%, 82.7% and 33.9%, respectively. For the COD removal, the solid part was removed by sedimentation process while the soluble part was stabilized anaerobically. The TSS removal efficiency was quite high, indicating that the system could separate suspended solid from wastewater. The effluent had dramatically lower amount of E. coli compared with the influent. The most common Salmonella serovars in the influent samples were Stanley, Rissen, and Anatum, respectively. Biogas production rates fluctuated due to variable organic inputs to the system. These results clearly indicate that the system of PFAD and UASB is capable of treating both solid and soluble portions of swine wastewater as well as reducing pathogenic bacteria to a certain extent. However, a polishing step is required to reduce organic content of the effluent in order to meet the limit set by the regulatory agency of Thailand. [ABSTRACT FROM AUTHOR]

The removal of phosphorus and nitrogen from wastewater has been a matter of great concern for several decades. In this study, a coupled electrochemical process, involving the electrochemical recovery of phosphate as struvite, electrochemical decomposition of the struvite recovered, and removal of the ammonia nitrogen by recycling the struvite electrolysis product, was tested to simultaneously recover phosphate and remove the ammonia nitrogen from swine wastewater. The results demonstrated that when a magnesium alloy was electrolyzed as the magnesium source of struvite crystallization, the recovery efficiency of the phosphate was 99%, at a current density of 2 mA/cm 2 for 45 min. When the struvite recovered was electrolyzed using seawater as a supporting solution, the ammonium in the struvite could be completely removed. The characterization analysis revealed that the active component of the electrolysis product was present as dissolved phosphate and magnesium and insoluble cattiite. An efficiency of >90% of ammonia nitrogen removal could be achieved by recycling the electrolysis product of struvite. A pilot-scale test performed for 30 recycle cycles demonstrated that approximately 93% of the recovery/removal efficiencies of the phosphate and ammonia nitrogen from swine wastewater could be achieved stably by the process proposed, which implied the presence of an important application value in the water eutrophication control and recovery of the phosphorus resources. [ABSTRACT FROM AUTHOR]

Pollution by heavy metals, such as copper and lead, has become a limiting factor for the land application of faecal manures, such as pig manure. This study was conducted to investigate the influence of composting process parameters, including aeration rate, moisture content and composting period, on the distribution of heavy metal species during composting, and to select an optimal parameter for copper and lead inactivation. Results showed that the distribution ratios of exchangeable fractions of copper and lead had a bigger decrease under conditions of aeration rate, 0.1 m3 min−1 m−3, an initial moisture content of 65% and composting period of 50 days. Suboptimal composting process conditions could lead to increased availability of heavy metals. Statistical analysis indicated that the aeration rate was the main factor affecting copper and lead inactivation, while the effects of moisture content and composting period were not significant. The rates of reduction of copper-exchangeable fractions and lead-exchangeable fractions were positively correlated with increased pH. The optimal parameters for reducing heavy metal bioavailability during pig manure composting were aeration rate, 0.1 m3 min−1 m−3, initial moisture content, 65%, and composting period, 20 days. [ABSTRACT FROM AUTHOR]

All life forms require phosphorus (P), which has no substitute in food production. The risk of phosphorus loss from soil and limited P rock reserves has led to the development of recycling P from industrial residues. This study investigates the potential of phosphorus recovery from sewage sludge and manure ash by thermochemical treatment (ASH DEC) in Finland. An ASH DEC plant could receive 46–76 kt/a of sewage sludge ash to produce 51–85 kt/a of a P-rich product with a P 2 O 5 content of 13–18%, while 320–750 kt/a of manure ash could be supplied to produce 350–830 kt/a of a P-rich product with a P content of 4–5%. The P 2 O 5 potential in the total P-rich product from the ASH DEC process using sewage sludge and manure ash is estimated to be 25–47 kt/a, which is significantly more than the P fertilizer demand in Finland’s agricultural industries. The energy efficiency of integrated incineration and the ASH DEC process is more dependent on the total solid content and the subsequent need for mechanical dewatering and thermal drying than on the energy required by the ASH DEC process. According to the results of this study, the treated sewage sludge and manure ash using the ASH DEC process represent significant potential phosphorus sources for P fertilizer production. [ABSTRACT FROM AUTHOR]

This study assessed an alternative concept for co-treatment of sewage and organic kitchen waste in Vietnam. The goal was to apply direct membrane filtration for sewage treatment to generate a permeate that is suitable for discharge. The obtained chemical oxygen demand (COD) concentrations in the permeate of ultrafiltration tests were indeed under the limit value (50 mg/L) of the local municipal discharge standards. The COD of the concentrate was 5.4 times higher than that of the initial feed. These concentrated organics were then co-digested with organic kitchen wastes at an organic loading rate of 2.0 kg VS/m³.d. The volumetric biogas production of the digester was 1.94±0.34 m³/m³.d. The recovered carbon, in terms of methane gas, accounted for 50% of the total carbon input of the integrated system. Consequently, an electrical production of 64 Wh/capita/d can be obtained when applying the proposed technology with the current wastes generated in Ho Chi Minh City. Thus, it is an approach with great potential in terms of energy recovery and waste treatment. [ABSTRACT FROM AUTHOR]

A two-step catalytic process for the production of biodiesel from waste frying oil (WFO) at low cost, utilizing waste animal-bone as catalyst and solar radiation as heat source is reported in this work. In the first step, the free fatty acids (FFA) in WFO were esterified with methanol by a catalytic process using calcined waste animal-bone as catalyst, which remains active even after 10 esterification runs. The trans-esterification step was catalyzed by NaOH through thermal activation process. Produced biodiesel fulfills all the international requirements for its utilization as a fuel. A probable reaction mechanism for the esterification process is proposed considering the presence of hydroxyapatite at the surface of calcined animal bones. [ABSTRACT FROM AUTHOR]

A novel bio-zeolite fixed-bed bioreactor combining with physicochemical and biological methods for mitigating ammonia inhibition was developed to improve the anaerobic digestion of ammonium-rich livestock wastes. The fixed-bed bioreactor was constructed by zeolite that was fixed using three different kinds of polymer materials including chlorinated polyethylene (CPE), polymer foaming sponge (PFS) and porous nylon (PN). Using ammonium-rich swine wastes (NH 4 + -N: 7511 mg/l) as substrate, a series of batch anaerobic fermentation experiments were carried out under 35 °C. The bioreactor suspending with CPE fixed zeolite showed the shortest start-up period (2 days) and the highest methane production (about 96 times higher than that of the Control) after 30-days anaerobic digestion. Furthermore, the higher and stable methane concentration and yield during 100-day of semi-continuous anaerobic digestion clearly indicated the long-term practical effectiveness of CPE-fixed zeolite bioreactor. Synergy of ammonia adsorption and microorganism immobilization by CPE fixed zeolite contributed to the enhanced anaerobic digestion efficiency. The developed novel CPE fixed zeolite bioreactor was suggested to be a favorable system for improve the anaerobic digestion of ammonium-rich agricultural wastes. [ABSTRACT FROM AUTHOR]

The combination of anaerobic digestion and hydrothermal liquefaction can provide enhanced energy production from animal wastes such as cow manure. Hydrothermal liquefaction (HTL) of anaerobic digestate is a novel approach for waste management to recover residual carbon Anaerobic digestion of cow manure was conducted at room temperature with different hydraulic retention times (HRT) viz. 10, 18, 28, 38, 50 and 60 days. The digested cow manure (16%w/w dry weight solids) obtained from various HRTs was subjected to hydrothermal liquefaction at 350°C, 18MPa for a fixed reaction time of 30 min in the presence of 5 wt % Na2CO3. The results showed cumulative biogas production in the range of 3.9-22.6 m3/kgVSadded. HTL of the resultant digestates led to ∼20-42 wt % biocrude yield. The biocrude has a higher heating value (HHV) of 28.4-31.2 MJ/kg. About 76% energy, ∼51-83% carbon and ∼2-4% nitrogen was recovered in the biocrude following HTL of the digestates. A positive energy balance was achieved for the products derived from the combination of anaerobic digestion and hydrothermal liquefaction. © 2015 American Institute of Chemical Engineers Environ Prog, 34: 1662-1673, 2015 [ABSTRACT FROM AUTHOR]

A sequential extraction approach was used to evaluate the effects of various combinations of passivators (sepiolite, phosphate rock, and coal fly ash) on the concentration and speciation of Cu in swine manure aerobic compost along with soil to which the compost had been applied. The results indicate that the various passivators altered the bound forms of Cu in pig manure and soil; the concentrations of exchangeable and Fe-Mn-bound Cu decreased, whereas the residual Cu concentration increased, indicating that Cu transformed to low-availability forms after the passivator treatments. The concentrations of the carbonate-bound and organic-bound Cu varied widely. Among all treatments, the treatment of the control + straw + sepiolite + coal fly ash (2.5 %) + phosphate rock (5.0 %) resulted in the most efficient passivation of Cu; the percentage of residual Cu reached 3.91-21.14 %, obviously surpassing the percentage for the control without passivation. The treatment of the control + straw + sepiolite + phosphate rock (2.5 %) resulted in the lowest residual Cu fraction (0.85 %) among passivator treatments. These results show that the addition of suitable combinations of passivators to the composting process reduced the availability of Cu and the risk of Cu pollution during the application of composted pig manure to soil. Passivation also decreased the Cu content of Apium graveolens. [ABSTRACT FROM AUTHOR]

The authors developed, in the current paper, within a simulation, a series of scenarios regarding the soil and water pollution decrease in the rural areas, by collecting the waste resulting from the livestock activities from the rural population owning livestock and processing this waste into manure for the crop production sector. Specifically, the authors propose a series of steps to determine the rural population to deliver the daily obtained livestock waste to a specially built and equipped platform where the waste to be properly managed and processed into manure. The authors have developed two scenarios whose materialization would contribute significantly in the decrease of pollution caused by livestock activities because of the current improper management. Moreover, the authors have compiled a primary data research across several communes of the Iasi County, in terms of livestock, regarding the livestock, taking to study and illustration the Andrieşeni commune, Iaşi County. [ABSTRACT FROM AUTHOR]

During the early phases of aerobic composting of animal manures, pathogens are inactivated primarily from the accumulation of heat produced by indigenous microbial activity. When compost materials are not exposed to these lethal temperatures, the required holding time needed to obtain a pathogen-free product that may be applied to fields is unknown. Consequently, a series of studies examined whether the carbon amendment (wheat straw, peanut hulls, rice hulls, and pine needles) added to animal manures affected survival of either Salmonella or E. coli O157:H7 during storage of compost mixtures at sublethal temperatures (20 to 40°C). Pathogens consistently survived for longer periods of time in compost mixtures prepared with pine needles than compost mixtures prepared with either of the other three carbon amendments. Pathogen inactivation in wheat straw- or peanut hull-amended compost mixtures was dependent on the target pathogen, moisture level, and storage temperature. Moisture levels in wheat straw-amended compost mixtures stored at 40°C had no effect on inactivation of E. coli O157:H7. In contrast, wheat straw-amended mixtures stored at 30 to 35°C and equilibrated to suboptimal moisture contents (30 to 40%) were less effective for inactivating pathogens compared with drier (25% moisture) or moister (60% moisture) mixtures. In peanut hull-amended compost mixtures, inactivation of E. coli O157:H7 was affected minimally by moisture levels, whereas Salmonella survival increased as the moisture level was decreased. The different inactivation responses of Salmonella and E. coli O157:H7 in compost mixtures prepared with wheat straw or peanut hulls and equilibrated to different moisture levels suggest that there are different mechanisms for inactivation. Hence, developing reliable guidelines relying on time-temperature for holding of compost mixtures at sublethal temperatures will be challenging and, perhaps, not possible. [ABSTRACT FROM AUTHOR]

Sanitizing human and animal waste (e.g., urine, fecal sludge, or grey water) is a critical step in reducing the spread of disease and ensuring microbially safe reuse of waste materials. Viruses are particularly persistent pathogens and can be transmitted through inadequately sanitized waste. However, adequate storage or digestion of waste can strongly reduce the number of viruses due to increases in pH and uncharged aqueous ammonia (NH3), a known biocide. In this study we investigated the kinetics and mechanisms of inactivation of the single-stranded RNA virus MS2 under temperature, pH and NH3 conditions representative of waste storage. MS2 inactivation was mainly controlled by the activity of NH3 over a pH range of 7.0-9.5 and temperatures lower than 40°C. Other bases (e.g., hydroxide, carbonate) additionally contributed to the observed reduction of infective MS2. The loss in MS2 infectivity could be rationalized by a loss in genome integrity, which was attributed to genome cleavage via alkaline transesterification. The contribution of each base to genome transesterification, and hence inactivation, could be related to the base pKa by means of a Bronsted relationship. The Bronsted relationship in conjunction with the activity of bases in solution enabled an accurate prediction of MS2 inactivation rates. [ABSTRACT FROM AUTHOR]

BACKGROUND Pyrolysis of slaughterhouse waste could promote more sustainable phosphorus (P) usage through the development of alternative P fertilizers. This study investigated how pyrolysis temperature (220, 350, 550 and 750 °C), rendering before pyrolysis, and wood or corn biomass additions affect P chemistry in bone char, plant availability, and its potential as P fertilizer. RESULTS Linear combination fitting of synchrotron-based X-ray absorption near edge structure spectra demonstrated that higher pyrolysis temperatures decreased the fit with organic P references, but increased the fit with a hydroxyapatite ( HA) reference, used as an indicator of high calcium phosphate ( CaP) crystallinity. The fit to the HA reference increased from 0% to 69% in bone with meat residue and from 20% to 95% in rendered bone. Biomass additions to the bone with meat residue reduced the fit to the HA reference by 83% for wood and 95% for corn, and additions to rendered bone by 37% for wood. No detectable aromatic P forms were generated by pyrolysis. High CaP crystallinity was correlated with low water-extractable P, but high formic acid-extractable P indicative of high plant availability. Bone char supplied available P which was only 24% lower than Triple Superphosphate fertilizer and two- to five-fold higher than rock phosphate. CONCLUSION Pyrolysis temperature and biomass additions can be used to design P fertilizer characteristics of bone char through changing CaP crystallinity that optimize P availability to plants. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

For farmers, management of cattle slurry (CS) is now a priority, in order to improve the fertilizer value of the slurry and simultaneously minimize its environmental impact. Several slurry pre-treatments and soil application methods to minimize ammonia emissions are now available to farmers, but the impact of such management strategies on groundwater is still unclear. A laboratory experiment was performed over 24 days in controlled conditions, with undisturbed soil columns (sandy soil) in PVC pipes (30 cm high and 5.7 cm in diameter). The treatments considered (4 replicates) were: a control with no amendment (CTR), injection of whole CS (WSI), and surface application of: whole CS (WSS), acidified (pH 5.5) whole CS (AWSS), the liquid fraction obtained by centrifugation of CS (LFS), and acidified (pH 5.5) liquid fraction (ALFS). An amount of CS equivalent to 240 kg N ha −1 was applied in all treatments. The first leaching event was performed 72 h after application of the treatments and then leaching events were performed weekly to give a total of four irrigation events (IEs). All the leachates obtained were analyzed for mineral and organic nitrogen, electrical conductivity (EC), pH, total carbon, and phosphorus. Total coliforms and Escherichia coli were also quantified in the leachates obtained in the first IE. The results show that both acidification and separation had significant effects on the composition of the leachates: higher NO 3 − concentrations were observed for the LFS and ALFS relative to all the other treatments, throughout the experiment, and lower NO 3 − concentrations were observed for acidified relative to non-acidified treatments at IE2. Acidification of both the LF and WS led to higher NH 4 + concentrations as well as an increase of EC for treatment ALFS relative to the control, in the first IE, and lower pH values in the AWSS. Furthermore, the E. coli and total coliform concentrations in AWSS, LFS, and ALFS were significantly higher than in WSI or WSS. In conclusion, none of the strategies generally used to minimize ammonia emissions impact positively on leaching potential relative to the traditional surface application of CS. Furthermore, some treatments, such as separation, might increase significantly the risk of leaching. [ABSTRACT FROM AUTHOR]

Purpose -- The purpose of this paper is to optimize manure allocation through nutrient budgeting strategy to meet crop nutrient requirements under maximizing economic returns and environmental constraints, and then to evaluate the economic and environmental effects of different nutrient budgeting strategies in animal excreta treatment. Design/methodology/approach -- In this study, a holistic integrated "ecological-economic" model is developed. It incorporates the systems of animal-crop production and waste treatment is developed for a pilot pig farm in China in order to simulate the economic and environmental effects of several nutrient budgeting strategies in excreta treatment for resource use. Findings -- The results reveal nutrient management deficiencies cause some serious environmental problems. The operations including biogas and composting are economically and environmentally efficient methods for manure management through nutrient budgeting strategy in an intensive animal farming with limited access to cropland. The nutrient budgeting strategy of constrained phosphorus, however, creates better environmental effects and brings more income from the waste treatment than the strategy of constrained nitrogen. The current standard of manure application in cropland which emphasizes on crop requirements for nitrogen should be reconsidered. Originality/value -- The paper is an original work and its methodology makes a meaningful contribution to understanding the relations between different nutrient budgeting strategies and their economic and environmental effects. [ABSTRACT FROM AUTHOR]

Estrogens and veterinary antibiotics (VAs) that are contained in animal excrements are spread into agricultural soil when using animal wastes on farmland. The impacts of VAs on soil health have already been well documented. However, there is limited knowledge regarding the influence of estrogens, particularly the combined effects of estrogens and VAs, on the soil microbial community. In this study, a short-term analysis (11 days) of the effect of the estrogens estrone and 17β-estradiol on soil microbial activity and on bacterial community structure was performed using a dehydrogenase activity (DHA) test and a PCR-denaturing gradient gel electrophoresis (DGGE) assay, respectively. Meanwhile, the potential influence of the VA sulfamethoxazole (SMX) as a co-pollutant on the effects of estrogens was examined. It was found that (1) estrone and 17β-estradiol biodegraded within hours in non-sterilized soil, even in the presence of up to 100 mg/kg SMX. (2) Estrone or 17β-estradiol alone markedly promoted soil DHA and stimulated the growth of partial bacteria strains, which were demonstrated as new or more intensive bands in DGGE profiles relative to the control treatment at the later incubation period. (3) The presence of SMX as a co-pollutant at concentrations of 10 and 100 mg/kg removed the stimulatory effects of estrogens on soil DHA and significantly reduced the DHA level to below the level of the untreated control. SMX also depressed the appearance of bacterial bands that were stimulated by estrone or 17β-estradiol alone. Moreover, the coexistence of SMX and estrogens induced additional bacterial bands, which may be tolerant strains. Overall, these results imply that the load of estrogens might serve as nutrient substances for soil microorganisms, whereas VAs as co-pollutants would cause a shift of these positive effects toward a significant threat to the natural soil microbial community. Therefore, the removal of VAs in animal waste is essential to ensure the safe use of animal waste in agricultural land. [ABSTRACT FROM AUTHOR]

This study describes a type of conversion technology of livestock waste to resources, including energy and fertilizer production. The most difficult part when treating livestock wastes is how to remove a high content of water in them. Generally, livestock wastes from concentrated animal feeding operations contain 90% water by weight. Therefore, an existing treatment system must be equipped with a wastewater treatment system as well as liquid/solid separation process. Moreover, the accompanied wastewater system results in a high capital, and operational and maintenance costs of having an entire system. However, the advanced compost and energy system is able to treat livestock wastes in one system. Thus, the advanced compost and energy system is a cost-effective method. In the advanced compost and energy system, technically, a high water content in livestock wastes evaporate by an exothermal reaction caused from a specific group of aerobic fermentation microorganisms. The microorganisms produce heat higher than 80°C thus evaporating moisture retained in wastes, while digesting long-chain molecules of organic compounds in them. Livestock wastes include cow, hog, and poultry manures in this study. Food wastes were also comparatively tested along with livestock wastes. Resulting materials showed relatively high caloric value and energy yield, 4,500 kcal/kg, in a heating value test. Therefore, they can be directly used as refuse derived fuel without adding such coals, cokes, and oils as energy boost additives that are normally utilized for a conventional refuse derived fuel manufacture process. Solid materials from the advanced compost and energy system can also prevent any secondary pollution from an incomplete combustion. The advanced compost and energy system is also environmentally benign with a zero discharge and even resource production from waste materials, which was recognized through lab-scale and full-scale experiments. [ABSTRACT FROM PUBLISHER]

Highlights: [•] Direct field emissions from organic fertilizer dominated environmental impacts. [•] The amount of avoided mineral fertilizers largely influenced environmental impacts. [•] Modified plant available nitrogen calculation considers total nitrogen emissions. [•] Calculation method for amount of avoided mineral fertilizers. [ABSTRACT FROM AUTHOR]

A spin-type centrifugal spreader was evaluated using fresh and aged poultry litter upon dry mass, product nitrogen (N), phosphorus (P) and potassium (K), incubation study soil available N and particle size distribution patterns. Relative to the aged litter (37% moisture content), the fresh litter (17% moisture content) had greater <1.00 mm particle size fraction weights and atmospheric particulate was launched, which posed as a potential fallout to adjacent fields, waterways and residences. Relative to the aged litter, the broadcast fresh litter resulted in higher coefficients of variation (CV) over its transverse distance, a narrower calculated space distance between passes for uniform spread and lower soil available N concentrations. For nitrogen application over the broadcast transverse distance the fresh litter displayed a high R 2 best fit 4th order polynomial distribution pattern, while the aged litter showed high R 2 best fit 6th order polynomial distribution pattern. A soil incubation study of the fresh and aged broadcast litter resulted in a more variable or lower R 2 best fit 2nd order polynomial distribution pattern. For both the fresh and aged litter, the calculated distance between passes to achieve a uniform mass distribution was greater than that required for the broadcast of soil available N. For the fresh litter, the soil available N and litter P concentration levels strongly correlated (relatively high p and R 2 values) with the <1.00 mm fraction weight, while for the aged litter this relationship was not as significant. In addition to reducing the health risk (i.e. pathogens, antibiotic residues and resistant bacteria) and/or environment issues (particulate fallout onto waterways, adjacent fields and/or residences) our study mass, particulate and N distribution patterns results suggest that poultry litter should be allowed to age before broadcast application is attempted. [Copyright &y& Elsevier]

Aiming to help municipalities develop effective education and outreach campaigns to reduce stormwater pollutants, such as pet waste, this study applied the Health Belief Model (HBM) to identify perceptions of dog waste and corresponding collection behaviors from dog owners living in a small U.S. city. Results of 455 online survey responses strongly support the HBM, a well-established health communication theory, and provide evidence for helping municipalities develop dog waste reduction campaigns. These findings guide dog waste behavior change campaign strategies discussed at the end of the article, and point to HBM's potential application to other environmental issues. [ABSTRACT FROM AUTHOR]

In this paper, a laboratory-scale experimentation allowed comparing the performances of two upflow anaerobic packed-bed filters filled with different packing materials and operating at mesophilic conditions (30°C) for treating slaughterhouse wastewaters. Methane production was experimentally evaluated considering different volumetric organic loading rates as well as feeding overloading conditions. Although filter performances declined with loading rates higher than 6 kg CODinm−3d−1, the chemical oxygen demand (COD) removal efficiency remained always above 60%. The experimental results allowed for determining kinetic parameters for bacterial growth rate and methane production, following Monod and Chen–Hashimoto models, respectively. Results demonstrated that the reactors reached a cellular retention time significantly greater than the hydraulic retention time. The kinetic parameter values (Ks, μmax) revealed the low microorganisms’ affinity for the substrate and confirmed the moderate biodegradability of slaughterhouse wastewater. The kinetic analysis also allowed the comparison of the filters performances with another anaerobic system and the assessment of the parameters useful for real-scale plant design. The system design, applied to a medium-sized Argentinean slaughterhouse, demonstrated to (i) be energetically self-sufficient and (ii) contribute to the plant's water heating requirements. [ABSTRACT FROM PUBLISHER]

Animal slurry management is associated with a range of impacts on fossil resource use and the environment. The impacts are greatest when large amounts of nutrient-rich slurry from livestock production cannot be adequately utilised on adjacent land. To facilitate nutrient redistribution, a range of different technologies are available. This study comprised a life cycle assessment of the environmental impacts from handling 1000kg of pig slurry ex-animal. Application of untreated pig slurry onto adjacent land was compared with using four different treatment technologies to enable nutrient redistribution before land application: (a) separation by mechanical screw press, (b) screw press separation with composting of the solid fraction, (c) separation by decanter centrifuge, and (d) decanter centrifuge separation with ammonia stripping of the liquid fraction. Emissions were determined based on a combination of values derived from the literature and simulations with the Farm-N model for Danish agricultural and climatic conditions. The environmental impact categories assessed were climate change, freshwater eutrophication, marine eutrophication, terrestrial acidification, natural resource use, and soil carbon, nitrogen and phosphorus storage. In all separation scenarios, the liquid fraction was applied to land on the pig-producing (donor) farm and the solid fraction transported to a recipient farm and utilised for crop production. Separation, especially by centrifuge, was found to result in a lower environmental impact potential than application of untreated slurry to adjacent land. Composting and ammonia stripping either slightly increased or slightly decreased the environmental impact potential, depending on the impact category considered. The relative ranking of scenarios did not change after a sensitivity analysis in which coefficients for field emissions of nitrous oxide, ammonia and phosphorus were varied within the range cited in the literature. Therefore, the best technology to implement in a given situation depends on the environmental problem in question, local policy, cost and practicality. [Copyright &y& Elsevier]