Effect of Superphosphate as Additive on Nitrogen and Carbon Losses during Pig Manure Composting

2013 ◽  
Vol 295-298 ◽  
pp. 1675-1679 ◽  
Author(s):  
Yi Ming Luo ◽  
De Gang Xu ◽  
Guo Xue Li

A pilot scale experiment of composting in rotting boxes used pig manure with cornstalks was carried out to study the effects of superphosphate on nitrogen and carbon losses including gas emissions. Besides control, there were five amended treatments with superphosphate addition (counted by P content) at 0.05, 0.10, 0.15, 0.20 and 0.25 molar ratio of initial nitrogen. The results indicated that superphosphate addition decreased ammonia volatilization, total nitrogen and carbon losses in composting. Total nitrogen losses of superphosphate-amended treatments were reduced by 9.3%, 14.6%, 30.1%, 45.8% and 71.5%, respectively. About 0.8% to 1.2% of initial nitrogen lost in the form of N2O emission, and the CH4 emission accounted for less than 0.3% of initial carbon. More than 0.15 molar ratio of superphosphate in compost materials caused considerable adverse effects on degradation of organic matter.

2007 ◽  
Vol 55 (11) ◽  
pp. 87-92 ◽  
Author(s):  
M.A. Camargo Valero ◽  
D.D. Mara

A simple apparatus was designed to collect ammonia gas coming out from waste stabilization ponds (WSP). The apparatus has a capture chamber and an absorption system, which were optimized under laboratory conditions prior to being used to assess ammonia volatilization rates in a pilot-scale maturation pond during summer 2005. Under laboratory conditions (water temperature = 17.1 °C and pH = 10.1), the average ammonia volatilization rate was 2,517 g NH3-N/ha d and the apparatus absorbed 79% of volatilized ammonia. On site, the mean ammonia volatilization rate was 15 g N/ha d, which corresponds to 3% of the total nitrogen removed (531 g N/ha d) in the maturation pond studied. A net nitrogen mass balance showed that ammonia volatilization was not the most important mechanism involved in either total nitrogen or ammonia removal. Nitrogen fractions (suspended organic nitrogen, soluble organic nitrogen, ammonia, nitrite and nitrate) from the M1 influent and effluent showed that ammonia is removed by biological (mainly algal) uptake and total nitrogen removal by sedimentation of dead algal biomass.


Soil Research ◽  
2012 ◽  
Vol 50 (5) ◽  
pp. 406 ◽  
Author(s):  
Ksawery Kuligowski ◽  
Robert John Gilkes ◽  
Tjalfe Gorm Poulsen ◽  
Baiq Emielda Yusiharni

Effects of thermally gasified pig manure ash (GA) and lime-free gasified ash (LF-GA) on properties of an acidic soil (pH 4.5) and the growth and elemental uptake of ryegrass (Lolium rigidum Gaudin) were investigated. The GA was an effective liming agent (2% addition raised soil pH from 4.5 to 7.9); both GA and LF-GA increased soil electrical conductivity and bicarbonate-extractable phosphorus (P). Soil fertilised with LF-GA supported slightly higher plant dry matter (DM) yield than GA (1.5–1.7 v. 1.2–1.5 g DM/kg soil) for the first harvest, due to greater initial P availability at pH <5 than at pH >6. However, plant yields for the subsequent two harvests were similar, as soil acidity dissolved lime in untreated ash (GA) over time. Maximum yields for ash-treated soil and soil treated with mono-calcium phosphate (MCP) were similar. Relative agronomic effectiveness of P sources for three harvests, based on plant P content compared with values for MCP, were 6, 11, and 12% for GA and 19, 10, and 33% for LF-GA. Internal efficiency of P utilisation was similar for all three P sources for each harvest, indicating that differences in yield were mostly a consequence of differences in P supply. Heavy metal concentrations in plants fertilised with ash were minor and within regulatory limits. In general, application of ash did not systematically affect the concentrations of elements (Al, B, Cd, Mg, Mn, Fe, Pb, S, Se) in plants.


2010 ◽  
Vol 150-151 ◽  
pp. 753-757 ◽  
Author(s):  
Xiong Hao Li ◽  
Yong Jie Xue ◽  
Min Zhou

This paper discussed the feasibility of unburned and non-autoclaved, steam cured bricks prepared by FGD byproducts from coal-fired power plants. The results show that FGD byproduct, aggregates, cementious materials and water could be used to prepare bricks during the process of stir and compaction under natural cure and steam cured condition. S4 and Z2 are the optimum design mixture composition. The maximum compressive strength and saturation coefficient are 28.7 MPa and 96.7%. FGD byproducts do no harm to environment and a pilot-scale experiment demonstrates that bricks made with FGDA can meet the MU10 level bricks technical requirement.


Catalysts ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1414
Author(s):  
Yekun Ji ◽  
Ye Zhou ◽  
Jinnan Wang ◽  
Aimin Li ◽  
Weilin Bian ◽  
...  

A visible-light-Fenton-like reaction system was constructed for the selective conversion of peroxymonosulfate to sulfate radical. Au@CoS, when doped on monoclinic BiVO4 {010} facets, promoted spatial charge separation due to the different energy band between the m-BiVO4 {010} and {110} facets. The visible-light response of m-BiVO4 was enhanced, which was attributed to the SPR effect of Au. And the photogenerated electrons were transferred from the m-BiVO4 {010} facet to Au via a Schottky junction. Owing to higher work function, CoS was able to capture these photoelectrons with acceleration of the Co(Ⅱ)/Co(Ⅲ) redox, enhancing peroxymonosulfate conversion to sulfate radical (Co2+ + HSO5−→ Co3+ + •SO4− + OH−). On the other hand, holes accumulated on m-BiVO4 {110} facets also contributed to organics oxidation. Thus, more than 95% of RhB was degraded within 40 min, and, even after five cycles, over 80% of RhB could be removed. The radical trapping experiments and EPR confirmed that both the sulfate radical and photogenerated hole were the main species for organics degradation. UV-vis DRS, photoluminescence (PL) and photoelectrochemical analyses also confirmed the enhancement of the visible-light response and charge separation. In a pilot scale experiment (PMS = 3 mM, initial TOC = 151 mg/L, reaction time = 4 h), CoS-Au-BiVO4 loaded on glass fiber showed a high mineralization rate (>60%) of practical wastewater.


2020 ◽  
Vol 270 ◽  
pp. 122373 ◽  
Author(s):  
Fengxiang Zhu ◽  
Chunlai Hong ◽  
Weiping Wang ◽  
Haohao Lyu ◽  
Weijing Zhu ◽  
...  

2020 ◽  
Vol 36 (2) ◽  
pp. 175-185
Author(s):  
Morten Lykkegaard Christensen ◽  
Kristian Keiding ◽  
Peter Vittrup Christensen

Abstract.Full-scale separation apparatuses were used to process mink and sow manure. Mink manure was pretreated with iron sulfate and polymer; pig manure was pretreated with only polymer. Testing was done to study how adding chemicals affected phosphorus removal. Chemical equilibrium simulations show that raw manure contains several minerals, i.e., struvite, calcium phosphate, and vivianite. The estimated mass of struvite fit well with the amount of magnesium measured in the solid material. The amount of calcium phosphate precipitation depended on the stability constant of the complexes of organic material and calcium ions, estimated at pK = 3.5–4. With polymer addition, it was possible to remove mineral-bound phosphorus but not organic-bound phosphorus and orthophosphate. With iron salt addition, it was possible to remove both phosphorus minerals and dissolved orthophosphate. The molar ratio between orthophosphate and iron ions in the precipitate was measured to be 2:3. These data fit well with the chemical equilibrium simulations, which predicted that vivianite would form when the iron ion concentration increased. The simulation also indicated that the amount of struvite decreased slightly with iron addition. Keywords: Coagulation, Flocculation, Solid-liquid separation, Vivianite, Wastewater.


2012 ◽  
Vol 33 (3) ◽  
pp. 345-358 ◽  
Author(s):  
Maciej P. Jakubiak ◽  

Abstract The paper presents results of experimental studies on removal of NOx from flue gas via NO ozonation and wet scrubbing of products of NO oxidation in NaOH solutions. The experiment was conducted in a pilot plant installation supplied with flue gas from a coal-fired boiler at the flow rate 200 m3/h. The initial mole fraction of NOx,ref in flue gas was approx. 220 ppm, the molar ratio X = O3/NOref varied between 0 and 2.5. Ozone (O3 content 1÷5% in oxygen) was injected into the flue gas channel before the wet scrubber. The effect of the mole ratio X, the NaOH concentration in the absorbent, the liquid-to-gas ratio (L/G) and the initial NOx concentration on the efficiency of NOx removal was examined. Two domains of the molar ratio X were distinguished in which denitrification was governed by different mechanisms: for X ≤ 1.0 oxidation of NO to NO2 predominates with slow absorption of NO2, for X >> 1.0 NO2 undergoes further oxidation to higher oxides being efficiently absorbed in the scrubber. At the stoichiometric conditions (X = 1) the effectiveness of NO oxidation was better than 90%. However, the effectiveness of NOx removal reached only 25%. When ozonation was intensified (X ≥ 2.25) about 95% of NOx was removed from flue gas. The concentration of sodium hydroxide in the aqueous solution and the liquid-to-gas ratio in the absorber had little effect on the effectiveness of NOx removal for X > 2.


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