scholarly journals Improving biogas production performance of dairy activated sludge via ultrasound disruption prior to microwave disintegration

2020 ◽  
Vol 81 (6) ◽  
pp. 1231-1241
Author(s):  
M. Al Ramahi ◽  
G. Keszthelyi-Szabó ◽  
S. Beszédes
Keyword(s):  
Activated Sludge ◽  
Specific Energy ◽  
Energy Input ◽  
Suspended Solids ◽  
Biogas Production ◽  
Production Performance ◽  
Specific Energy Input ◽  
Net Production ◽  
Energy Assessment ◽  
Dairy Sludge

Abstract In this study, ultrasound disruption was employed to enhance the efficiency of microwave disintegration of dairy sludge. Results revealed that ultrasound specific energy input of 1,500 kJ/kg TS was found to be optimum with limited cell lysis at the end of the disruption phase. Biodegradability study suggested an enhancement in suspended solids reduction (16%) and biogas production (180 mL/gVS) in floc disrupted (deflocculated) samples when compared to sole microwave pretreatment (8.3% and 140 mL/gVS, respectively). Energy assessment to attain the 15% optimum solubilization revealed a positive net production of 26 kWh per kg sludge in deflocculated samples compared to 18 kWh in flocculated (sole microwave) samples. Thus, ultrasound disruption prior to microwave disintegration of dairy sludge was considered to be a feasible pretreatment technique.

Ultrasound pre-treatment of waste activated sludge

2006 ◽  
Vol 6 (6) ◽  
pp. 35-42 ◽  
Author(s):  
J (Hans) van Leeuwen ◽  
Beril Akin ◽  
Samir Kumar Khanal ◽  
Shihwu Sung ◽  
David Grewell ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Specific Energy ◽  
Energy Input ◽  
Oxygen Demand ◽  
Protein Release ◽  
Waste Activated Sludge ◽  
Bacterial Cells ◽  
Particle Size Reduction ◽  
Specific Energy Input ◽  
Power Ultrasound

Waste activated sludge (WAS) is more difficult to digest than primary sludge due to rate limiting cell hydrolysis. High-power ultrasound can effectively disintegrate the bacterial cells and thus enhance the subsequent digestion. This research examines the effectiveness of ultrasound pretreatment on WAS disintegration at different specific energy inputs, ultrasonic densities and total solids (TS) contents. The results show that the cut diameter (d50) for WAS with 2% TS content declined nearly 6.5-fold at an ultrasonic density of 0.67 W/ml. For higher TS contents of 4 and 6%, higher densities of 1.03 and 0.86 W/ml, respectively, were needed to achieve the same degree of particle size reduction. The efficacy of ultrasonic disintegration measured as soluble chemical oxygen demand (SCOD) release was primarily governed by ultrasonic density (W/ml); whereas ultrasonic density did not show a significant effect on protein release at all TS levels. SCOD release of about 320 mg SCOD/g TS was obtained at a TS content of 2% and specific energy input of 5 kWs/gTS. The SCOD release, however, decreased to 160 and 90 mgSCOD/gTS at 4 and 6% TS contents, respectively. The highest protein release of 73 mg/gTS was obtained at a TS content of 2% and specific energy input of 10 kWs/gTS. The sludge disintegration efficiency declined significantly at higher TS content. Thus, there is a limiting TS concentration that could be effectively disintegrated by ultrasound, and this is governed by the capability of an ultrasonic unit in producing cavitation. The degree of disintegration also depends on types of ultrasonic unit used.

Effect of O2/CH4 ratio on the optimal specific-energy-input (SEI) for oxidative reforming of biogas in a plasma-shade reactor

2013 ◽  
Vol 22 (5) ◽  
pp. 681-684 ◽  
Author(s):  
Jinglin Liu ◽  
Xiaobing Zhu ◽  
Xiaosong Li ◽  
Kai Li ◽  
Chuan Shi ◽  
...  
Keyword(s):  
Specific Energy ◽  
Energy Input ◽  
Specific Energy Input ◽  
Oxidative Reforming

scholarly journals Perspectives of pulsed electric field application for larvae biomass drying

2020 ◽  
Vol 10 (4) ◽  
pp. 12-21
Author(s):  
I.A. Shorstky ◽  
◽  
O. Parniakov ◽  
S. Smetana ◽  
◽  
...  
Keyword(s):  
Electric Field ◽  
Specific Energy ◽  
Energy Input ◽  
Pulsed Electric Field ◽  
Field Application ◽  
Specific Energy Input ◽  
Drying Time ◽  
Drying Temperature ◽  
Electric Filed ◽  
Pulsed Electric Field Treatment

The perspectives of pulsed electric field (PEF) application for larvae biomass drying are considered. Drying process optimization was carried out using two-way analysis of variance in the range of applied specific energy input of from 0 up to 20 kJ/kg and drying temperature of from 50 up to 90°С. It was found out that application of pulsed electric field treatment allowed marked decreasing of larvae biomass drying time from 183 to 124 minutes for the samples treated with electric filed intensity of E = 2 kV/cm and specific energy of 20 kJ/kg. Based on the obtained experimental data the optimal drying and PEF treatment parameters for larvae biomass were determined for the ranges of drying temperature – 82–85℃ and specific energy input – 4.1–6.6 kJ/kg.

scholarly journals Application of Emerging Cell Disintegration Techniques for the Accelerated Recovery of Curcuminoids from Curcuma longa

2021 ◽  
Vol 11 (17) ◽  
pp. 8238
Author(s):  
Hoang Le-Tan ◽  
Thomas Fauster ◽  
Jelena Vladic ◽  
Tina Gerhardt ◽  
Klara Haas ◽  
...  
Keyword(s):  
Specific Energy ◽  
High Performance ◽  
Energy Input ◽  
Curcuma Longa ◽  
Time Saving ◽  
Specific Energy Input ◽  
Beneficial Effects ◽  
High Specific Energy ◽  
The Impact ◽  
Cell Disintegration

Curcuminoids, the bioactive compounds with many beneficial effects on human health, exist in Curcuma longa (turmeric). In the present study, the impact of different cell disintegration techniques to enhance total curcuminoid recovery (TC) from fresh and dried turmeric was investigated. The impact of thermal pretreatment (TP), ultrasound pretreatment (UP), enzyme pretreatment (EP), and pulsed electric field pretreatment (PEF) on the recovery of curcumin (CUR), demethoxycurcumin (DMC), and bis-demethoxycurcumin (BDMC) from fresh and dried turmeric were studied. The cell disintegration index (Zp) and high-performance liquid chromatography (HPLC) analysis of curcuminoids were performed to evaluate the efficiency of the applied techniques. With fresh turmeric, the highest curcuminoid recovery was 83.6 mg/g dry basis with EP. The highest structural tissue damage was obtained with UP achieving a cell disintegration level of 92.5%. The technology with the highest time-saving and low specific energy input was PEF with a total curcuminoid recovery of 80.9 mg/g dry basis. Working with dried turmeric, the drying required high specific energy input for 72 h at 50 °C; however, the untreated dried sample reached 125.3 mg/g dry basis of TC without further pretreatment after drying.

scholarly journals Use of pulsed electric fields to induce breakage of glandular trichome cells in leaves of fresh patchouli (Pogostemon cablin Benth.): Specific energy input consumption

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Sukardi Sukardi ◽  
Sudjito Soeparman ◽  
Bambang Dwi Argo ◽  
Yudy Surya Irawan
Keyword(s):  
Electric Field ◽  
Electric Fields ◽  
Specific Energy ◽  
Energy Input ◽  
Glandular Trichome ◽  
Specific Energy Input ◽  
Variable Electric Field ◽  
Pogostemon Cablin ◽  
Cell Changes ◽  
Electric Field Treatment

Research has been performed using a pulsed electric field (PEF) to damage plant cells to obtain bioactive compounds before extraction. However, research into the use of PEF to break down the glandular trichome (GT) cells of patchouli for essential oil extraction is still limited. The purpose of this study was to determine the specific energy input needed to break patchouli leaf GT cells by PEF treatment. Patchouli leaves were harvested at 7 months of age, then treated with PEF. GT cell changes were analyzed using scanning electron microscopy. The results show that treatment with variable frequencies caused GT cell wrinkling and treatments with a variable electric field caused GT cell rupture. Electric field treatment at E=133.33 V/cm and a PEF exposure time of 2 seconds or E=116.66 V/cm and 3 seconds of PEF exposure resulted in consistent rupture of GT cells. Energy consumption of 0.049 kJ/cm3 promoted GT cell wall shrinkage and consumption of 0.59 kJ/cm3 broke GT cell walls.

Is sonication effective to improve biogas production and solids reduction in excess sludge digestion?

2008 ◽  
Vol 57 (4) ◽  
pp. 479-483 ◽  
Author(s):  
C. M. Braguglia ◽  
G. Mininni ◽  
A. Gianico
Keyword(s):  
Activated Sludge ◽  
Residence Time ◽  
Energy Input ◽  
Biogas Production ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
High Energy ◽  
Organic Load ◽  
Ultra Sound

Results of three semi-continuous anaerobic tests were reported and discussed. Each test was carried out by two parallel anaerobic reactors fed with waste activated sludge, either as it was sampled from the sewage treatment plant of Rome North or previously disintegrated by ultra-sound treatment. Activated sludge was sonicated at the energy input of 5,000 or 2,500 kJ kg−1 dry solids corresponding to a disintegration degree of approximately 8 or 4%, respectively. Sonication proved to be effective both in increasing VS destruction and cumulative biogas production. The best increase of VS destruction (from 30 to 35%) was achieved in test #3 carried out at high organic load (10 d residence time) and low energy input (2,500 kJ kg−1 dry solids). The best increase in cumulative biogas production (from 472 to 640 NL after 67 d of tests i.e.) was obtained in test #1 at low organic load (20 d residence time) and high energy input (5,000 kJ kg−1 dry solids). Specific biogas production varied in the tests carried out with untreated sludge (0.55 – 0.67 Nm3 kg−1 VS destroyed) but was practically unchanged for all the tests with sonicated sludge (0.7 Nm3 kg−1 VS destroyed).

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