Mechanism and kinetics of low-temperature thermo-chemical conversion process for sewage sludge

2001 ◽  
Vol 44 (10) ◽  
pp. 341-347 ◽  
Author(s):  
P. Ho ◽  
L. Shao ◽  
G. Gu ◽  
G. Li
Keyword(s):  
Sewage Sludge ◽  
Low Temperature ◽  
Chemical Conversion ◽  
Transfer Characteristic ◽  
Reaction Model ◽  
Volatile Matter ◽  
Conversion Process ◽  
Gravimetric Analysis ◽  
Aliphatic Compounds ◽  
Elementary Analysis

The low-temperature thermo-chemical conversion process for sewage sludge is a prospective technology, through which the energy in the sludge can be recovered. With the help of elementary analysis of sewage sludge and its conversion products, thermal gravimetric analysis (TGA) of the sludge and GC/MS analysis of the derived oil, a study was carried out on element transfer, characteristic conversion temperature and conversion reaction mechanism of the process. The following results are obtained: 1) the predominant conversion reactions are distillation of aliphatic compounds, splitting of protein peptide bonds and group transfer; and 2) the main components involved in the conversion are aliphatic compounds and protein, with the lower reaction temperature for the former, the higher for the latter and the highest for saccharides. Based on the mechanism analyses, the simplified reaction model of the thermo-chemical conversion process for sewage sludge consists of two serial competitive reactions (producing volatile matter and char respectively). The estimated Arrhennius kinetic parameters of the reaction model based on TGA testing results are A1 = 4.15×106 1/s, n1 = 2, E1 = 98 kJ/mol; A2 = 1.42×105 1/s, n2 = 2, E2 = 85 kJ/mol; A3 = 1.01×1012 1/s, n3 = 4, E3 =190 kJ/mol; A4 = 1.33×109 1/s, n4 = 4,E4 = 146 kJ/mol.

Fate of Benzalkonium Chloride in a Sewage Sludge Low Temperature Conversion Process Investigated by LC-LC/ESI-MS/MS

2007 ◽  
Vol 35 (1) ◽  
pp. 81-87 ◽  
Author(s):  
Heike Sütterlin ◽  
Rainer Trittler ◽  
Sebastian Bojanowski ◽  
Ernst A. Stadlbauer ◽  
Klaus Kümmerer
Keyword(s):  
Sewage Sludge ◽  
Low Temperature ◽  
Benzalkonium Chloride ◽  
Conversion Process ◽  
Esi Ms

Research on low temperature thermo-chemical conversion to oil process for sewage sludge

2000 ◽  
Vol 42 (3-4) ◽  
pp. 301-308 ◽  
Author(s):  
P. He ◽  
G. Gu ◽  
L. Shao ◽  
Y. Zhang
Keyword(s):  
Sewage Sludge ◽  
Low Temperature ◽  
Thermal Energy ◽  
Energy Recovery ◽  
Technological Development ◽  
Chemical Conversion ◽  
Reaction Conditions ◽  
Sludge Incineration ◽  
Secondary Pollutants ◽  
Incineration Process

The process of low temperature thermo-chemical conversion of municipal sewage sludge to oil is a new developing technology in developed countries, which is developed based on some poor fuels processing process in recent years. The process has the advantages of reasonable thermal energy recovery (the whole process is a net thermal energy exporting process), suitable cost and less secondary pollutants. This research included the reaction conditions versus the converted products distributions, the reaction conditions versus the ratio of the process thermal energy input and output, exploring of reaction mechanisms, creating of reaction kinetics models. These results contribute not only to having a clear understanding about the technological features and evaluating the prospectives of technological development, but also provide a sound basis for the technological development on a larger scale. It is concluded that: 1) the sludge treatment process is a net thermal energy producer. 2) The optimal conversion temperature is 270°C, referring to making energy recovery ratio maximum. 3) The parameters of simple conversion reaction kinetics are n=2, A=8.5 S-1 and E=37.9 KJ/mol. 4) The secondary pollutants of the process can be effectively controlled. 5) The investment intensity of the process could be similar to that of the sewage sludge incineration process, and the operational economics of the process are obviously superior to those of the sewage sludge incineration process. The research results show that the technical-economic feasibility of low temperature thermo-chemical conversion process is favorable, because the reaction conditions are more moderate and the separation process of the products is more easily realized.

Drying and low temperature conversion - a process combination to treat sewage sludge obtained from oil refineries

1996 ◽  
Vol 34 (10) ◽  
pp. 133-139 ◽  
Author(s):  
Martin Th. Steger ◽  
Wolfgang Meißner
Keyword(s):  
Sewage Sludge ◽  
Low Temperature ◽  
Fuel Oil ◽  
Conversion Process ◽  
Water Separation ◽  
Oil Refineries ◽  
Solids Concentration ◽  
Oil Water Separation ◽  
Oil Water ◽  
Process Combination

Sewage sludge from oil refineries poses special problems in the disposal of solid, and often hazardous waste. Drying followed by low temperature conversion (i.e., pyrolysis at 400°C) renders sludge to fuel oil and char. This process was operated in full scale, using an input of 40 tonnes. An overall oil yield of 35% and a rate of 45% of char referring to the input of dried solids was achieved during the conversion process using a sludge having 16% dried solids concentration. Halogenated organics and PAH present in the the feed sludge were reduced during the conversion process by 98.4% and 83.7% respectively. Mercury was completely removed from the fuel oil and char through adsorption to the residue of oil/water separation (centrifugal sludge). The conversion oil produced meets fuel oil standards and can be used for industrial purposes. The char produced can be used as a reducing agent in steel manufacture.

Enhancement of IR transparency of arsenic sulfide materials via plasma-chemical conversion of the initial arsenic monosulfide in low-temperature RF plasma

2018 ◽  
Vol 52 (1) ◽  
pp. 015203 ◽  
Author(s):  
Leonid Mochalov ◽  
Alexander Logunov ◽  
Roman Kornev ◽  
Sergey Zelentsov ◽  
Andrey Vorotyntsev ◽  
...  
Keyword(s):  
Low Temperature ◽  
Chemical Conversion ◽  
Rf Plasma ◽  
Arsenic Sulfide ◽  
Plasma Chemical

scholarly journals Elementary analysis and energetic potential of the municipal sewage sludges from the Gdańsk and Kościerzyna WWTPs

2018 ◽  
Vol 26 ◽  
pp. 00004
Author(s):  
Arkadiusz Ostojski
Keyword(s):  
Sewage Sludge ◽  
Water Content ◽  
Calorific Value ◽  
High Water ◽  
Municipal Sewage ◽  
Municipal Sewage Sludge ◽  
High Water Content ◽  
Sewage Sludges ◽  
Heating Value ◽  
Elementary Analysis

This paper aims to present municipal sewage sludge (MSS) elementary analysis and energetic potential based on measurement of heat of combustion (higher heating value HHV) and calculation of calorific values (lower heating value LHV). The analysis takes into the consideration water content in sewage sludge, at different utilization stages, in wastewater treatment plants in Gdańsk Wschód and Kościerzyna – Pomeranian Voivodeship. The study yielded the following results (in % dry matter): ash 19÷31 %, C - 31÷36 %, H - 5÷6 %, N - 4÷6 %, O - 28÷32 %, S – 1 %. Calorific value of stabilized sludges in Gdańsk was on average 13.8÷15 MJ/kg. In case of sludges not undergoing digestion from Kościerzyna WWTP, the calorific value was at the level of 17.5 MJ/kg. Thus, sewage sludges are good energy carriers. High water content though is the problem, as it lowers the useful effect of heat. There is no alternative for thermal sewage sludge neutralization, which is in conformity with valid Polish National Waste Management Plan (KPGO 2022).

Low-temperature, polysulfide reactions of conjugated ene carbonyls: A reaction model for the geologic origin of S-heterocycles

1987 ◽  
Vol 11 (6) ◽  
pp. 563-571 ◽  
Author(s):  
Robert T. LaLonde ◽  
Louis M. Ferrara ◽  
Michael P. Hayes
Keyword(s):  
Low Temperature ◽  
Reaction Model

The low-temperature SCR of NO over rice straw and sewage sludge derived char

2010 ◽  
Vol 156 (2) ◽  
pp. 321-327 ◽  
Author(s):  
Jin Sun Cha ◽  
Jong-Cheol Choi ◽  
Jeong Huy Ko ◽  
Young-Kwon Park ◽  
Sung Hoon Park ◽  
...  
Keyword(s):  
Sewage Sludge ◽  
Low Temperature ◽  
Rice Straw ◽  
Scr Of No ◽  
Low Temperature Scr
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