| Literature DB >> 26104412 |
Eun Young Lee1, Min Hwan Oh1, Seung-Hak Yang1, Tae Han Yoon2.
Abstract
In this study, the optimal operation factors forEntities:
Keywords: Anaerobic Digestive Fluid; Struvite; Swine Manure
Year: 2015 PMID: 26104412 PMCID: PMC4478498 DOI: 10.5713/ajas.14.0679
Source DB: PubMed Journal: Asian-Australas J Anim Sci ISSN: 1011-2367 Impact factor: 2.509
Characteristics of the thermophilic anaerobic digestion fluid
| Parameter | Concentration range | Average |
|---|---|---|
| TCOD (mg/L) | 15,900 to 18,600 | 17,125 |
| TKN (mg/L) | 3,100 to 4,046 | 3,534 |
| TSS (%) | 3.08 to 3.26 | 3.15 |
| VSS (%) | 56.15 to 62.18 | 59.08 |
| NH4+-N (mg/L) | 2,974 to 3,907 | 3,400 |
| PO43−-P (mg/L) | 1,120 to 1,468 | 1,342 |
| pH | 8.10 to 8.26 | 8.15 |
TCOD, total chemical oxygen demand; TKN, total Kjeldahl nitrogen; TSS, total suspended solid; VSS, volatile suspended solid.
Experimental conditions of struvite crystallization
| Parameters | Conditions | ||
|---|---|---|---|
|
| |||
| Test 1 | Test 2 | Test 3 | |
| Sample | Anaerobic digestion supernatant of swine manure, 1 L | ||
| pH | pH 9, 10, 11, 12, 13 | pH 8.8 | pH 8.8 |
| Molar ratio of PO43−:Mg2+ | 1:1 | 1.5 | 1:1, 1,1, 1,2, 1,3, 1,4, 1:1.5 |
| Agitating velocity, temp. | 100 rpm, Room temp. | 100 rpm, 200 rpm, Room temp. | 100, Room temp. |
| Reaction time | 1 h | 10 min, 1 h, 24 h | 1 h |
Figure 1Effect of the initial pH on the struvite crystallization of anaerobic digestive fluid of swine manure.
Figure 2Effect of mixing time on the struvite crystallization of anaerobic digestive fluid of swine manure. * This experiment was done at 200 rpm for 1 h; others (without asterisk) were done at 100 rpm for 10 min, 1 h, and 24 h.
Figure 3Effect of PO42− -P to Mg2+ mole ratio on the struvite crystallization of anaerobic digestive fluid of swine manure.
Figure 4Microscopic pictures of struvite crystal morphology: scanning electron microscopy at pH 8.8 with magnification of ×700 (a), light microscopy at pH 8.8 with magnification of ×100 (b); The measure bars on (a) indicate 20 μm.
Figure 5X-ray diffraction patterns of struvite crystal.