nitrogen emission
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2021 ◽  
Vol 937 (3) ◽  
pp. 032059
Author(s):  
V Gusev ◽  
L Zazykina ◽  
I Sysoeva

Abstract New equipment set for the processing of manure, the main waste of poultry farms, into a range of ancillary products with predetermined properties and parameters is described. This technology decreases the emission of harmful substances into the atmosphere. The method of preparation of manure for the usage as a solid fuel with decreased expenses for drying was developed; this method allows for the significant decrease of nitrogen content in the manure (resulting in the decreased nitrogen emission at burning). The method involves the preliminary mixing of the manure with a natural absorbent (3-5% of the dry matter of manure) sieved through the 0.2 mm screen; separation of the mixture (by centrifuging or pressing) to solid fraction (moisture content 45-56%) and liquid fraction; drying of the solid fraction in a cylinder drier to moisture content 12-22%; the final product can also be pelleted. A part of the product can be burned in a furnace to produce the heat for the drying of the solid fraction; liquid fraction can be further processed in a coagulator to extract protein or can be used as a liquid fertilizer or ingredient of the liquid substrates in the hydroponic greenhouses.


2021 ◽  
Vol 31 (2) ◽  
pp. 160-167
Author(s):  
Farah Nabila ◽  
Vita Restitrisnani ◽  
Retno Adiwinarti ◽  
Agung Purnomoadi

This study aimed to evaluate feed protein utilization and nitrogen emission of young and mature Kejobong goats fed different concentrations of concentrate and forage. Sixteen heads of male Kejobong goats consisted of eight heads young goats (5 months old) and eight heads mature goats (9 months old) with initial body weight (BW) of 14 ± 1.46 kg, and 22.3 ± 1.99 kg, respectively were arranged in a nested design. All goats were fed with two different rations of concentrate and forage (C30 = 30% concentrate: 70% forage and C70 = 70% concentrate: 30% forage). The data were analyzed using ANOVA procedure. This study showed that the average daily gain (ADG) did not differ (p>0.05) in both ages, but it differed (p<0.05) in concentrate levels. The ADG of goats fed C70 was significantly higher (p<0.05) than those of goats fed C30 in both ages. The digestible crude protein (DCP) of young and mature goats was similar (p>0.05), while there was a significantly difference (p<0.05) between the treatments. There were no effects of different ages of goats and concentrate levels on feed conversion ratio (FCR) (p>0.05). The different ages of goats and concentrate levels affected N retention (g/day) and total N2O emission (g/day). It was concluded that ADG, DCP and FCR did not differ in mature and young Kejobong goats, while young goats had less N2O emissions than mature goats. Goats fed 70% of concentrate improved their ADG, DCP, N retention (g/day) and produced less N2O emission.


2021 ◽  
pp. 117870
Author(s):  
Xiao Zhu ◽  
Jianlin Shen ◽  
Yong Li ◽  
Xuejun Liu ◽  
Wen Xu ◽  
...  

2021 ◽  
Vol 26 (1) ◽  
pp. 5-13
Author(s):  
Jerzy Michalski ◽  
Tadeusz Frączek

In the article, based on the literature, the phase changes in iron nitrides on iron powders and on solid samples were discussed. Phase transformations in NH3/H2 atmosphere and in inert atmospheres are discussed. The similarity of phase transformations in different atmospheres used during annealing were indicated. The conditions of phase transformations in iron nitrides during annealing in NH3/H2 atmosphere, argon and vacuum were discussed. Phase transformations occurring during annealing in the NH3/H2 atmosphere are reversible and there is a hysteresis phenomenon. During the phase transformation ɛγ' in the NH3/H2 atmosphere until the transformation is completed, nitrogen emission to the atmosphere takes place. On the other hand, the condition for the course of the transformation of γ'ɛ is the nitrogen flow from the atmosphere to the surface. Phase changes during heating in vacuum and argon are irreversible. During continuous heating at a rate of 30 K / min in vacuum and argon, nitrided iron powders, two phase transformations may occur, which are not accompanied by weight loss, the first (α+γ')γN in the temperature range 540÷550°C in a vacuum and 620÷630°C in argon and the second (γ+γ')ɛ in the range of 610÷620°C in vacuum and 690÷710°C in argon. In the case of heating in argon, the onset of weight loss was recorded at a temperature of about 860°C. Whereas in vacuum the denitration of nitrogen austenite γN ends at this temperature. During annealing at the temperature of 360°C, the phase change ɛγ′ in the ɛ/γ′ layer is accompanied by an increase in the thickness of the γ′ phase, which is at the expense of the thickness of the ɛ zone, while the total thickness of the layer after the transformation is the same as its initial thickness. At the temperature of 420°C, after the completion of the γ′ transformation, the formed monophasic layer γ′ is thicker than the ɛ/γ′ layers in the initial state.


Nitrogen ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 128-138
Author(s):  
Vanessa Theodoro Rezende ◽  
Thierry Bonaudo ◽  
Ricardo Barboza Alves ◽  
Rafael Araújo Nacimento ◽  
Augusto Hauber Gameiro

Soybean is one of the most traded products. Naturally, soy fixes nitrogen through biological symbiosis. Its cultivation transforms natural inert atomic nitrogen into its reactive forms. The advancement of soybean can have environmental impacts, both locally and globally. This study estimated nitrogen flows and their use efficiency in the Brazilian soybean production chain applying material flow analysis. We innovate proposing a new indicator to estimate the “cascade effect of nitrogen” in a framework of 12 years (2007 to 2019). We hypothesized that it is capable to show accumulated nitrogen emissions through the chain. Besides, the method can show the main sources of nitrogen to the environment. The biological fixation was the largest entry. The efficiency in the use of nitrogen was 81% for grain production, and the nitrogen cascade indicator, which represents the ratio of the nitrogen emission in the environment to the total nitrogen available in the product, was only 5.2% in the soybean meal production chain for the year of 2019, with a clear trend of increasing during the period. Thus, Brazil contributes significantly to global nitrogen emissions in the environment since the country is an important producer and player in the world market.


2020 ◽  
Vol 38 (10) ◽  
pp. 1176-1184
Author(s):  
Xuqin Pan ◽  
Maonan Chen ◽  
Fan Wang ◽  
Qibin Li

The effect of biochar on the removal of organic and nitrogen contaminants from leachate in a semi-aerobic aged refuse biofilter (SAARB) was investigated. A preset amount of biochar was mixed with the aged refuse to explore the enhancement ability of pollutant removal by characterizing the leachate effluent and gas. The results showed that biochar contributed to the removal of organic and nitrogen pollutants from the leachate and that increasing the amount of biochar added led to higher colour number, chemical oxygen demand, ammonia nitrogen, and total nitrogen removal efficiencies. Furthermore, the addition of biochar significantly increased the removal of large molecule organic pollutants from the leachate. The improved removal of organics was due to the considerable number of surface functional groups and the large surface area of the biochar, which effectively absorbed and removed a significant amount of the organic matter from the leachate. Biochar elevated the dissolved oxygen concentration in the semi-aerobic system, which facilitated the completion of the nitrification reaction. It also promoted denitrification by acting as a supplementary carbon source. The nitrous oxide (N2O) emissions decreased as the amount of biochar added increased. When the biochar proportion reached 3%, the N2O emission was only 1.11% of the original total nitrogen and the di-nitrogen emission was 19.61%. The findings of this study can be used to improve the treatment of leachate using biochar combined with a SAARB.


2020 ◽  
Vol 227 ◽  
pp. 117401
Author(s):  
Mingrui Ma ◽  
Weihua Chen ◽  
Shiguo Jia ◽  
Ming Chang ◽  
Buqing Zhong ◽  
...  
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