جستجوی مقالات مرتبط با کلیدواژه « acidic sludge » در نشریات گروه « پزشکی »

Inappropriate management of hazardous industrial waste has caused many problems for human societies. The aim of this study was to evaluate the management of acidic sludge produced in industrial parks in Isfahan, Iran, in the year 2013.
This cross-sectional study was conducted in 180 plants in 5 industrial parks, including Oshtorjan, Mobarakeh, Razi, Jay, and Mourchekhort, Iran. The status of the plants was examined using a questionnaire. For other industrial parks, the amount of acidic sludge was calculated based on yield of norm.
Findings: Acidic sludge was investigated in 8 different industrial subgroups. The paraffin and organic solvents group, with the amount of 3092 tons per hectare per year, produced the highest amount of acidic sludge and the oil treatment subgroup, with 623 tons per hectare per year, produced the lowest amount. Razi Industrial Park (2700 tons per year) and Urea Natanz (62 tons per year), respectively, produced the highest and lowest amount of sludge in the paraffin and organic solvents subgroup. In the subgroup of treatment oil, Mourchekhort (746 tons per year) and Alavicheh (39 tons per years) produced the highest and lowest amount of sludge, respectively.
Acidic sludge has been identified as hazardous waste. Thus, in order to reduce its adverse effects on the environment, the use of management methods which significantly reduce its produced volume.

Acidic sludge is a by-product of used motor-oil reprocessing industries which is disposed of in the environment as hazardous waste material. The polymer bitumen under certain conditions is produced from mixing Bentonite soil, polymer styrene - butadiene – styrene(SBS) and acidic sludge. The aim of this study was retrieval of acidic sludge from polymer bitumen using additives such as bentonite soil and polymer SBS. In this experimental study, the effect of additives with different weight percentages on the performance parameters of bitumen was evaluated. At first, spilled oil phase into the acidic sludge was isolated with centrifugal concentrator. Acidic sludge and additives with a high shear mixer 2500 rpm were mixed together for 30 minutes at 180 °C. Finally, performance tests on acidic sludge and obtained products were performed.The obtained data were analyzed using Excel microsoft 2007. The results indicated that the performance parameters such as softening point temperature, weight loss, penetration degree, PI, Frass breaking point and thermal sensitivity increased from 37 °C, 1/3 %, 230 dmm, -0.07854, -5 °C and 0.0451 to 54 °C, 1%, 130 dmm, 2/7094, -11 °C, 0.02721 respectively. The bentonite soil and SBS polymer in weight percentages of 2 and 4 respectively were the suitable additives in retrieval of acidic sludge from the polymer bitumen.

Thousand tons of acidic sludge is produced daily as by-product in the used motor oil refining industries. The acidic sludge contains unsaturated compounds which are non-polar and asphaltene. The objective of this study was performance improvement of acidic sludge by using the additives (bentonite, polymer SBS, sodium hydroxide and the lime) so that recovery to bitumen. The polymer styrene - butadiene - styrene (SBS) is bitumen modifier as one of the elastomer - thermoplastic with weight percentages (2 to 4 percent), bentonite due to the chemical structure as fillers, stabilizers and agent concentration with weight percentages (1,2,4,6,8,10) and lime and sodium hydroxide were used to decreasing acidity rate of acidic sludge and promoting the role of bentonite stability in bitumen with ratios equal (1 to 5 g) were mixed with acidic sludge of industry (samples 50 g) and their effect on the acidic sludge was investigated. Evaluation of studies indicated that because of increasing acidic sludge softening point, temperature from 25 to 48 oC, decrease weight loss from 3% to 1.25, promoting the penetration degree to 230 mm, Frass breaking point to -7 and penetration index (PI) to the degree standard set (+1), the acidic sludge properties and performance were modified. The measurement of last three parameters was unavailable in primary sludge. Environmental and health hazards of acidic sludge will be decreases by treatment and neutralization. Also obtained products can be used in the building and road construction according to its specific bitumen criteria and characteristics.