Feasibility study of recycling and converting acidic sludge to bitumen in used motor oil refining industries

Background and Aims: 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.Materials and Methods: 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.Results: 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.Conclusion: 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.Key words: Recovery - Acidic sludge - Used motor oi

A novel method for recovery of acidic sludge of used-motor oil reprocessing industries to bitumen using bentonite and SBS

ABSTRACT Acidic sludge is a by-product from used motor oil reprocessing industries, which thousand tons of this sludge are disposed into the environment as a hazardous waste material daily. The acidic sludge contains unsaturated compounds that are polar and asphaltene. The bitumen under certain conditions is produced from mixing of bentonite, polymer styrene – butadiene – styrene (SBS), and acidic sludge. Context and purpose: The objective of this study was the recovery of acidic sludge to bitumen using additives such as bentonite and SBS. Also, the effect of additives with different weight percentages (wt%(on the performance parameters of bitumen was evaluated. At first, spilled oil was separated from the acidic sludge by a centrifugal concentrator. Then, concentrated acidic sludge and additives were mixed in together. Finally, the performance tests were carried out to compare the quality of acidic sludge with the obtained products.The results indicated that performance parameters such as softening point (SP), weight loss, penetration degree, PI, Frass breaking point, and temperature susceptibility (TS) were promoted 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. According to the paired sample t-test analysis, a significant difference was found between the bentonite dosage and the improved performance parameters from concentrated acidic sludge and obtained products (pvalue ≤.001). The bentonite and SBS with 2 and 4 wt%, respectively were determined as the suitable additives in the recovery of acidic sludge to bitumen

Slaughterhouse Wastewater Treatment by Combined Chemical Coagulation and Electrocoagulation Process

Slaughterhouse wastewater contains various and high amounts of organic matter (e.g., proteins, blood, fat and lard). In order to produce an effluent suitable for stream discharge, chemical coagulation and electrocoagulation techniques have been particularly explored at the laboratory pilot scale for organic compounds removal from slaughterhouse effluent. The purpose of this work was to investigate the feasibility of treating cattle-slaughterhouse wastewater by combined chemical coagulation and electrocoagulation process to achieve the required standards. The influence of the operating variables such as coagulant dose, electrical potential and reaction time on the removal efficiencies of major pollutants was determined. The rate of removal of pollutants linearly increased with increasing doses of PACl and applied voltage. COD and BOD5 removal of more than 99% was obtained by adding 100 mg/L PACl and applied voltage 40 V. The experiments demonstrated the effectiveness of chemical and electrochemical techniques for the treatment of slaughterhouse wastewaters. Consequently, combined processes are inferred to be superior to electrocoagulation alone for the removal of both organic and inorganic compounds from cattle-slaughterhouse wastewater

Application of High Rate Stabilization Ponds for Treatment of Kermanshah City Slaughterhouse

Stabilization ponds have high capability for treating the wastewater with high organic and hydraulic loading. Hence this system is a popular means of wastewater treatment for certain industries such as slaughterhouses, dairies and food processing plants. The main objective of this study was to investigate the efficiency of stabilization ponds for treating a high organic load wastewater receiving effluent from a slaughterhouse plant in Iran. The efficiency of Kermanshah slaughterhouse wastewater treatment plant was studied over six months from September 2000 to March 2001. The general conditions and operation of the plant were considered and some wastewater treatment indexes such as pH, TSS, BOD5, COD, coliform and fecal coliform in influent and effluent were determined.The quality of the plant effluent has significant difference with the standard limits recommended by Iranian Environmental Protection Agency. The average amounts of TSS, BOD5, COD, total and fecal coliform in effluent were 280.67 mg/l, 353.17 mg/l , 580.5mg/l, 1.51*107MPN/100ml and 2.10*105 MPN/100ml respectively. The results showed that the effluent could not be used for irrigation or discharged to surface water based on the recommended standard by Iranian Environmental Protection Agency. Also, the comparison of the average number of fecal coliform in effluent with the microbiological quality guideline of World Health Organization (WHO) showed that the effluent was not acceptable for use in unrestricted  irrigation

Efficiency of Worm Reactors in Reducing Sludge Volume in Activated Sludge Systems

The activated sludge process is the most widely used on a global scale for the biological treatment of both domestic and industrial effluents. One problem associated with the process, however, is the high volume of sludge produced. Excess sludge treatment and disposal account for up to 60% of the total operating costs of urban wastewater treatment plants due to the stringent environmental regulations on excess sludge disposal. These strict requirements have encouraged a growing interest over the last few years in reducing sludge volumes produced at biological treatment plants and a number of physical, chemical, and mechanical methods have been accordingly developed for this purpose. The proposed methods are disadvantaged due to their rather high investment and operation costs. An alternative technology that avoids many of these limitations is the worm reactor. In this study, the characteristics of this technology are investigated while the related literature is reviewed to derive the optimal conditions for the operation of this process in different situations

Evaluation of waste management, manufacturing industries, from an environmental standpoint (Case Study: Savojbolagh city Alborz Province)

  Introduction and Purpose: The quantity and quality of industrial wastewater is variable owing to the different lines of production and product variety of industry. Meeting the effluent standards requires proper environmental management. The current study aimed to evaluate the industrial wastewater management in Savojbolagh, Alborz, Iran from an environmental perspective in 2013-2014. Methods: This study was cross-sectional. The data were collected through field visits, questionnaire (of Iran's Environmental Protection Agency), and controlling data from industrial plants with more than 50 workers (totally 108 units). The questionnaire included questions about the quantity, quality, and management of wastewater. Based on an environmental perspective, the way of managing industrial wastewater was classified into four index: wastewater production, per capita production, BOD (Biochemical oxygen demand) per capita, and COD (Chemical Oxygen Demand) per capita which were rated from1 to 6. For each index, a higher score was defined for better management. Results: The wastewater produced by industries was estimated to be 1942 cubic meters per day. Food industry alone produced 59% of the entire industrial wastewater. The industry related to animal slaughtering was shown to have the highest BOD per capita, 320 g/day per every worker; and the cellulose industry enjoyed the highest COD per capita, 561 g/day per every worker. 76% of the industries under investigation had no strategy to reduce the wastewater production. 34% of these industries possessed treatment plants, while only 17% of them were following the effluent discharge standards. The most common method of treated and untreated wastewater disposal was found to be absorbing well. Conclusion: Based on this assessment, the management of wastewater was revealed to be favorable in non-metallic minerals industry, but unfavorable in agriculture industry as the wastewater produced by this industry was considered to be an environmental pollutant

Reliability Performance Assessment of Wastewater Treatment Plants in Assessment of the Reliability Performance of WWTPs in West Azarbaijan

Performance of wastewater treatment plants (WWTPs) in Urmia, Khoy, Miandoab, Salmas, and Bookan were evaluated during the years 2008 to 2011 based on the reliability approach. The approach predicts the overall performance of WWTPs and their processes and, thereby, makes the screening of treatment technologies possible. The required BOD5, COD, and TSS data were collected using the records available at West Azerbayejan Water and Wastewater Company, local surveys, and interviews with operators. Statistical analysis was performed by SPSS. The valid Niku modeling was employed to calculate the Rmeasured , Revaluated, COR, and expected percentages of compliance with discharge standards and a significant relationship was found among these parameters. The results also showed the log normal distribution of effluent characteristics. Furthermore,SBR and biolac processes exhibited higher values of Rmeasured (90-100%), Revaluated (93-100%), and expected percentages of compliance with the discharge standards (95-99.97%) in all the WWTPs studied but lower values of COR (0.41-0.64) than those in aerated lagoons. The coefficients obtained in this study can, therefore, be used for the development and construction designs of similar systems

Degradation of Amoxicillin Using Modified Graphite Felt and Fe3 O4 Nanocatalyst As Electro-Fenton Process

Background: Amoxicillin is the most commonly used antibiotics that draws more attractions due to induce bacterial resistance. This compound can enter the aquatic environment through different routes including sewage and waste disposal of medical health centers, veterinary and industries. The aim of this study was removal of amoxicillin from aqueous environments by Electro-Fenton process using modified graphite felt and synthesized Fe3O4 nanoparticles. Methods: Fe3O4 nanoparticles were synthesized by co- precipitation method. Graphite felt also modified due to avoid aeration. The structural and physical characteristics of nanocatalyst and also modified graphite felt were analyzed by SEM, EDS and BET techniques. After optimization of pH and time variables, the parameters of applied current, amoxicillin concentration, catalyst load and the distance between electrodes were designed using Design Expert 7.0 software and optimized by the response surface method. Results: The graphite felt modification resulted in increase in surface area from 0.89 to 1.92 m2/g. The maximum removal of amoxicillin (97.11%) was obtained in optimal operational conditions (pH=3, time=60 min, applied current =180 mA, amoxicillin concentration=20 mg/L, catalyst load 1 g/L, the distance between electrodes =2 cm) Conclusion: The result of this study indicated that electro-Fenton process using Fe3O4 nanoparticles and modified Graphite felt without external aeration is an effective method for amoxicillin remova

Wastewater Sludge Stabilization Using Lime A Case Study of West Ahwaz Wastewater Treatment Plant

Lime stabilization is a chemical method used for wastewater sludge stabilization. It is capable of decreasing large quantities of pathogens and of preventing microbial degradation of sludge organic materials. The main objective of the present experimental research was to investigate stabilization of the sludge from west Ahwaz wastewater treatment plant by lime addition and to control if the microbial quality of this sludge conforms to the USEPA standards for sludge reuse and safe disposal. The study was carried out on a pilot scale in 5 stages over a period of 12 months (July 2005 to June 2006) at west Ahwaz wastewater treatment plant laboratory using raw sludge. For the purposes of this study, a 30-liter reactor was commissioned and loaded with sludge and appropriate quantities of hydrated lime were added based on the solid waste percent. The parameters used to determine stabilization efficiency were pH, Total Coliform, Fecal Coliform, and parasite eggs. The results showed that lime addition at a ratio of 265g Ca(OH)2/kg. ds was the optimum level for sludge stabilization in westAhwazwastewater treatment plant, which is acceptable from both economic and technical viewpoints. The method is capable of achieving class B but never satisfied class A of USEPA standards