Kraft-Mill Biosolids Treatment by Conventional and Biphasic Fermentation

1999 ◽  
Vol 40 (11-12) ◽  
pp. 169-177 ◽  
Author(s):  
S. Ghosh ◽  
D. C. Taylor
Keyword(s):  
Energy Recovery ◽  
Single Stage ◽  
High Rate ◽  
Net Energy ◽  
Municipal Sludge ◽  
Nutrient Source ◽  
Two Phase ◽  
Fuel Gas ◽  
Reduction Efficiency ◽  
Nitrogen Phosphorus

Kraft primary and mixed primary-activated sludges were gasified by thermophilic (50 °C) high-rate and mesophilic two-phase digestion. Kraft sludges were deficient in nitrogen, phosphorus, and other unidentified nutrients. Municipal sludge proved to be a much better nutrient source than inorganic salts. Performance of the mesophilic (35°C), two-phase anaerobic digestion (TPAD) system was about the same as that of thermophilic single-stage, high-rate digestion at a 10-day HRT as judged in terms of methane yield (0.17 SCM/kg VS added) and VS reduction efficiency (43%). The mesophilic TPAD process yielded a higher methane-content (65%) fuel gas; it is capable of exhibiting higher net-energy recovery efficiency than thermophilic single-stage digestion.

scholarly journals Multi-Country Scale Assessment of Available Energy Recovery Potential Using Micro-Hydropower in Drinking, Pressurised Irrigation and Wastewater Networks, Covering Part of the EU

Water ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 899
Author(s):  
Djordje Mitrovic ◽  
Miguel Crespo Chacón ◽  
Aida Mérida García ◽  
Jorge García Morillo ◽  
Juan Antonio Rodríguez Diaz ◽  
...  
Keyword(s):  
Drinking Water ◽  
Northern Ireland ◽  
Energy Recovery ◽  
Large Scale ◽  
Significant Proportion ◽  
Value Added ◽  
Cost Effective ◽  
Net Energy ◽  
Water Networks ◽  
Scale Assessment

Studies have shown micro-hydropower (MHP) opportunities for energy recovery and CO2 reductions in the water sector. This paper conducts a large-scale assessment of this potential using a dataset amassed across six EU countries (Ireland, Northern Ireland, Scotland, Wales, Spain, and Portugal) for the drinking water, irrigation, and wastewater sectors. Extrapolating the collected data, the total annual MHP potential was estimated between 482.3 and 821.6 GWh, depending on the assumptions, divided among Ireland (15.5–32.2 GWh), Scotland (17.8–139.7 GWh), Northern Ireland (5.9–8.2 GWh), Wales (10.2–8.1 GWh), Spain (375.3–539.9 GWh), and Portugal (57.6–93.5 GWh) and distributed across the drinking water (43–67%), irrigation (51–30%), and wastewater (6–3%) sectors. The findings demonstrated reductions in energy consumption in water networks between 1.7 and 13.0%. Forty-five percent of the energy estimated from the analysed sites was associated with just 3% of their number, having a power output capacity >15 kW. This demonstrated that a significant proportion of energy could be exploited at a small number of sites, with a valuable contribution to net energy efficiency gains and CO2 emission reductions. This also demonstrates cost-effective, value-added, multi-country benefits to policy makers, establishing the case to incentivise MHP in water networks to help achieve the desired CO2 emissions reductions targets.

The Temperature-Phased Anaerobic Biofilter Process

1994 ◽  
Vol 29 (9) ◽  
pp. 213-223 ◽  
Author(s):  
Sandra K. Kaiser ◽  
Richard R. Dague
Keyword(s):  
System Performance ◽  
Anaerobic Treatment ◽  
Size Ratio ◽  
High Rate ◽  
Phase System ◽  
Optimum Size ◽  
Treatment Technology ◽  
Two Phase ◽  
In Series ◽  
Two Temperature

The “temperature-phased anaerobic biofilter” or TPAB process (U.S. Patent pending), is a new high-rate anaerobic treatment system that includes a thermophilic (56°C) biofilter connected in series with a mesophilic (35°C) biofilter providing for two-temperature, two-phase treatment. Three TPAB systems of different thermophilic:mesophilic reactor size ratios were operated at system HRTs of 24 hrs, 36 hrs, and 48 hrs to characterize performance and to determine if an optimum size ratio exists between the thermophilic and mesophilic phases. The three TPAB systems achieved SCOD reductions in excess of 97% and TCOD reductions in excess of 90% for a synthetic milk substrate over a range of system COD loadings from 2 g COD/L/day to 16 g COD/L/day. There was little difference in performance between the three TPAB systems based on COD reduction and methane production. The 1:7 ratio of thermophilic:mesophilic phase TPAB system performed as well as the 1:3 and 1:1 size ratio TPAB systems. In applications of the process, a relatively small thermophilic first-phase can be used without sacrificing overall two-phase system performance. The TPAB process is a promising new anaerobic treatment technology with the ability to achieve higher efficiencies of organic removals than is generally possible for single-stage anaerobic filter systems operated at equivalent HRTs and organic loadings.

pH regulation of the first phase could enhance the energy recovery from two‐phase anaerobic digestion of food waste

2021 ◽  
Author(s):  
Qing Zhao ◽  
Samuel Gyebi Arhin ◽  
Ziyi Yang ◽  
Haopeng Liu ◽  
Zongye Li ◽  
...  
Keyword(s):  
Anaerobic Digestion ◽  
Food Waste ◽  
Energy Recovery ◽  
Ph Regulation ◽  
Two Phase

Eco-friendly fabricated nonporous carbon nanofibers with high volumetric capacitance: improving rate performance by tri-dopants of nitrogen, phosphorus, and silicon

2017 ◽  
Vol 4 (12) ◽  
pp. 2024-2032 ◽  
Author(s):  
Yuwei Yang ◽  
Xueyuan Hou ◽  
Chenfeng Ding ◽  
Jin-Le Lan ◽  
Yunhua Yu ◽  
...  
Keyword(s):  
Carbon Nanofibers ◽  
High Rate ◽  
Rate Performance ◽  
Volumetric Capacitance ◽  
High Rate Performance ◽  
Nitrogen Phosphorus

High rate performance of nonporous carbon nanofibers achieved via tri-dopants of nitrogen, phosphorus, and silicon.

Study on Expander-Auxiliary Compressor Unit Used in Refrigeration System

2011 ◽  
Vol 354-355 ◽  
pp. 811-818
Author(s):  
Tao He ◽  
Zhi Yuan Wang ◽  
Yu Qing Xue
Keyword(s):  
Energy Recovery ◽  
Rotation Speed ◽  
Cooling Capacity ◽  
Compressor Unit ◽  
Performance Parameters ◽  
Refrigeration System ◽  
Two Phase ◽  
Speed Up ◽  
Testing Condition ◽  
Auxiliary Unit

The throttling valve used in the refrigeration system always causes energy loss. In this paper, an energy recovery device in the refrigeration system which was composed of an expander-auxiliary compressor unit to replace the throttling valve was investigated. On the basis of thermodynamic analysis, two typical arrangements which the auxiliary compressor was connected to the main compressor of the refrigeration system were compared and the system performance parameters were discussed. A prototype of an expander-auxiliary unit was manufactured to observe the expander performance using R410A as refrigerant. The results showed the reliability of the unit working in the two-phase flow condition with the rotation speed up to 21020 rpm. And the maximum increases in the cooling capacity by 3.9% and COP by 3.2% could be obtained under the testing condition.

Operando XRD study of LiMn1.5Ni0.5O4 high-voltage cathode under high-rate charge-discharge reaction

2019 ◽  
Vol 34 (S1) ◽  
pp. S8-S13
Author(s):  
T. Konya ◽  
Y. Shiramata ◽  
T. Nakamura
Keyword(s):  
Volume Change ◽  
Low Voltage ◽  
High Rate ◽  
Insertion Reaction ◽  
Phase Reaction ◽  
Two Phase ◽  
Voltage Range ◽  
Lattice Volume ◽  
Rate Determining Step ◽  
Spinel Cathode

Structural variation of LiMn1.5Ni0.5O4 spinel cathode during the Li+ extraction/insertion reaction was studied using operando X-ray diffraction. It was found that the reaction in the voltage range from 3.5 to 4.9 V consisted of two consecutive two-phase reactions, where three spinel phases of LiMn1.5Ni0.5O4, Li0.5Mn1.5Ni0.5O4 and Mn1.5Ni0.5O4 were identified and the lattice volume change in the whole reaction was evaluated as 6%. The reactions were symmetric and reversible under low-current conditions, but some asymmetries were detected during high current operation. Furthermore, a two-phase reaction between cubic and tetragonal phases was observed in the low-voltage reaction at 2.1–3.5 V, where the lattice volume change was approximately 4.9%. The rate-determining step was discussed based on these operando results.

scholarly journals Extraction of tetracycline using the ionic liquid-based aqueous two phase systems: Single-stage versus multi-stage

2018 ◽  
Vol 24 (4) ◽  
pp. 387-397 ◽  
Author(s):  
Yi Liu ◽  
Li Chen ◽  
Jun Zhou ◽  
Zongcheng Yan
Keyword(s):  
Extraction Efficiency ◽  
Ph Value ◽  
Influence Factors ◽  
Volume Ratio ◽  
Line Length ◽  
Single Stage ◽  
Two Phase ◽  
Extraction Behavior ◽  
Multi Stage ◽  
Tie Line

Ionic liquids-based aqueous two-phase extraction (ILs-ATPE) offers an alternative approach to the extraction of tetracycline (TC) through their partitioning between two phases. Single-stage and multi-stage strategies have been evaluated and compared for the purification of TC using ATPE composed of 1-butyl-3-methylimidazolium halide ([Bmim]X(X=Cl,Br)) and K2HPO4. The influence factors on single-stage extraction behavior of TC were optimized systematically, including the pH value, tie line length, and volume ratio. The optimal extraction efficiency of TC could reach above 95% when the volume ratio is higher than 1.5 and the tie line length is 30.52%. The multi-stage ATPE was also investigated by simulating a three-stage crosscurrent operation in test tubes. According to the TC isotherm curve and respective McCabe?Thiele diagrams, a predicted optimized scheme of the countercurrent multi-stage ATPE was determined. TC can be purified in the IL-rich top phase with a final extraction efficiency of 99% and a final TC concentration of 0.25 mg/mL, if a three- -stage [Bmim]Cl-K2HPO4 ATPE with volume ratio of 0.5 and tie line length of 30.52% was employed. Thus, the multi-stage extraction with small volume ratio is necessary to achieve a higher recovery yield, resulting in the reduction of the IL consumption.

scholarly journals Surgical outcome with single stage procedure for neglected congenital talipes equinovarus

2019 ◽  
Vol 6 (1) ◽  
pp. 37
Author(s):  
Vishal H. Chandak ◽  
Ketan J. Khatri ◽  
Shraddha H. Chandak
Keyword(s):  
Developing Countries ◽  
Soft Tissue ◽  
Single Stage ◽  
High Rate ◽  
Prolonged Treatment ◽  
Soft Tissue Release ◽  
Wedge Osteotomy ◽  
Congenital Talipes Equinovarus ◽  
Talipes Equinovarus ◽  
Congenital Talipes

<p class="abstract"><strong>Background:</strong> Congenital talipes equinovarus is one of the commonest congenital anomalies. In developing countries like India especially in the rural population still there are many myths, culture and awareness issues regarding this deformity. Many patients get initial treatment with casting but tend loose follow ups in this prolonged treatment. To give optimal results in these scenarios, the technique for single stage procedure which includes bony and soft tissue repair gives excellent results.</p><p class="abstract"><strong>Methods:</strong> In a retrospective longitudinal study, 13 children with neglected clubfeet were involved. Valid consent, clinical and radiological evaluation was done. Patients underwent single stage (bony and soft tissue) procedure described in the study. Post operatively data was collected and scoring was done as per International clubfoot study group (ICSG) at each follow ups.<strong></strong></p><p class="abstract"><strong>Results:</strong> A total 13 children out of whom 9 were male and 4 females, all having unilateral deformity were studied. The age group was between 5-22 years (mean 13.5). Postoperatively, the children were followed at 6 months intervals. As per ICSG score 10 patients had excellent results, 3 patients had good results and none had poor results. 2 patients had minor complication - delayed wound healing (2-3 weeks).</p><p class="abstract"><strong>Conclusions:</strong> Treatment of neglected clubfoot using single stage procedure dorsal close wedge osteotomy with soft tissue release has a high rate of good and excellent results, with low frequency of complications. It is a good alternative to conventional procedures for management of neglected clubfeet in developing countries, where compliance of patient is a problem.</p>

Sign in / Sign up

Export Citation Format

Share Document