A long chain polyacrylate which was a functional composition of a new water-based stripper (WLOAC) for art masking fluid was prepared using azobisisobutyronitrile under the solution polymerization method. The WLOAC was mixed with natural latex to form an art masking fluid (WACN). The optimized preparation conditions, i. e., reaction time 4 h, reaction temperature 80 °, C, and stirring rate 200 r/min were selected by the orthogonal experimental design method. The proton (1H NMR) and carbon (13C NMR) nuclear magnetic resonance spectra of polyacrylate were recorded. There were no peaks at 6. 5–, 5. 5 ppm in 1H NMR and at 128. 3 ppm and 130. 2 ppm in 13C NMR, which indicated that the radical polymerization was indeed occurred. The rheological properties of the WLOAC emulsions were investigated by a rheometer, and the rheology tests indicated that the WLOAC emulsion is a pseudoplastic fluid. The surface tension, peel strength, tensile strength and scanning electron microscopy (SEM) of WACN were all determined. The results showed that the surface tension decreased by the addition of WLOAC. The peel strength decreased from 0. 58 to 0. 29 N/mm with WLOAC increased from 5 to 12. 5 wt%. With the addition of WLOAC, the tensile stress increased from 10. 56 to 22. 36 MPa. The SEM results showed that WACN coatings could be detached without causing any damage to the paper substrate.

This process provides a method for prevention of deposit formation over the outer surface of process equipment in alcohol plants from sugar beet molasses and particularly in sugar cane molasses.In this process, the fermented molasses are softened and precipitated before entering the distillation column. Firstly, the pH of the fermented molasses will be increased up to 10-10.5 by sodium carbonate. In other words, the solution is carbonized and then its temperature will be increased up to 50oC and a certain amount of ethanol is added to the mixing solution. After adding some ethanol, the components in molasses (specially carbonized calcium and magnesium cations), are precipitated and deposited quickly. Also, the liquid and deposited phases are separated and liquid phase (free of calcium and magnesium cation) is sent into the distillation column.

Many changes in combine harvesting machines can be noticed in recent years. All attempted to improve field capacity of combine. One of these changes is the introduction of stripper head. While using this type of the head, ground speed of combine can be increased up to 10km/hour. In this study a new method was introduced in pea harvesting in Iran. We tried to use stripper head in addition to transporting channel to harvest pea. The transport of chick pea pods from the stripper to the thresher was carried out not by the regular feed chains but by the throwing action of the stripper cylinder combined with the force of the produced wind thereof. The objectives of this research was to determine the effect of more important factors. Many parameters can affect transporting of materials in this mechanism. Type of stripper fingers, rotational speed of stripper rotor, inlet area of head and shape of channel towards threshing mechanism are also important factors. To study the effect of these variables, a mechanism was constructed which its inlet area was adjustable. By using of a variable speed electromotor the rotational speed of rotor could be varied. Four, types of stripper fingers were designed and constructed. Finally the transporting channels were made in three shapes. A factorial experimental based on completely random design with four factors, each at three levels, and four replicates was conducted for test anafysis under load. Experiments were undertaken in Tehran's Agricultural Machinery Engineering Discipline's Lab. A meshed conveyor was used for artificial feeding of pea pods to the stripper. The most suitable treatments level for better transportation of material as well as the effect on the shattered, damaged and returned pods was determined. Results indicated that all factors have significant effect on material transporting and head loss, at 1% probability level. Finally, after much theoretical and experimental work it was. indicated that the stripper finger of medium triangular form, inlet area of 32° opening in head interance, 75 rad/sec for rotational speed of rotor and a channel with the ratio of outlet/inlet equal to 0.20 was a desirable design for harvesting of pea in this study.

The main problem is the high energy consumption in the gas sweetening process, especially in the distillation column, which makes it necessary to optimize the energy consumption of this process. A new method was used in this study for heat integration of natural gas sweetening process. For this purpose, the liquid and vapor streams leave the absorption column entered the upper and lower section of the stripper column, respectively. The feed to the stripper column was preheated by the bottom product the stripper column. Liquid and vapor streams reduce hot and cold utilities of the distillation column, and feed preheating reduces the heating duty of the reboiler. The recovered solvent was then precooled by sweet gas. According to the results, the proposed method reduced energy consumption of the basic process by 67%. Based on the results obtained from calculating the amount of CO2 emission, the amount of emission of this poisonous gas decreased by approximately 70%. Moreover, proposed process could reduce total annual cost (TAC) of the basic process in the maximum value of 66.76%. This reduction in TAC is due to the reduction of operating cost and capital cost by 66.77 and 66.66% respectively. Also, in comparison with the basic process, exergy loss of the novel process decreased by 66.5%.

Background: Fire and explosion hazards are considered as the first and second major hazards in process industries. Objective: The aim of this study was to quantitatively assess the fire and explosion hazardsas well as relative classification of such hazards in a petrochemical industry. Methods: This wasa quantitative study in which the process units were selected based on parameters affecting the risk of fire and explosion. Later, these parameters were analyzed using DOW’s fire and explosion index (F&EI). Technical data to determine the index were obtained through process documents and reports as well as the fire and explosion guideline. Following calculating the DOW’s index, the high and low risk process units were determined. Findings: The stripper column with a rank of 226 and the naphtha tank with a rank of 64 were determined as the most and least disastrous process units. The level of hazardwas determined as severe for columns (F&EI>158), heavy for magna-former reactor and gasoline furnace (127< F&EI£158), and moderate for hydrodealkylation reactor and naphtha tank (61< F&EI£96). The radius of exposure was calculated at 57 meters for stripper column. Conclusion: The fire and explosion index is a suitable measure to determine the high and low risk areas of an industry. The stripper column as the most disastrous process unit needs more sensitive methods for hazard assessment.

In the engineering practice, there are two basic alternatives of physicochemical treatment for the removal of volatile compounds from process wastewaters: stripping with air or stripping with steam. In this work, these alternatives are investigated and compared in the case of a real industrial problem that is typical for the fine chemical industry and general conclusion is drawn. The removal of the organically bound halogens, called adsorbable organically bound halogens, is investigated. The two alternatives, air and steam stripping, are first modeled in the professional software environment of ASPEN PlusÒ. The model is validated on the data of an existing air stripper for the removal of organic halogens. Same organic halogens removal is applied for the design of a steam stripper. It is proved that the steam stripping shows better operability and economic performance than the air stripping; moreover, the volatile and/or adsorbable organically bound halogen compounds can be recovered in the distillate and they can be reused improving the sustainability.

Due to the limited uranium reserves, the abundance of thorium compared to it, not being used in nuclear proliferation, and other advantages of thorium fuels over uranium fuels, the development of the thorium fuel cycle in various countries, including Iran, is considered. In this research, the separation and recovery processes of thorium from a real acidic leach liquor solution with a concentration of 500 mg/L thorium on a laboratory scale to produce thorium oxide precipitate were evaluated. The operating parameters affecting the extraction, stripping, and chemical precipitation processes of thorium include the type of extractant (acidic, basic, and neutral), the concentration of the extractant (0.05-1 M), aqueous phase acidity (0.032-6.92), equilibrium time (5-60 min), type and concentration of stripper (1-7 M) and precipitating agent were studied by the univariate method in each section. According to the experimental results, Di(2-ethylhexyl) phosphoric acid with a concentration of 1 M as extractant, aqueous phase acidity equal to 0.1, equilibrium time 60 min, sulfuric acid with a concentration of 5 M as a stripper, and ammonia as a precipitating agent were selected. Recovery of thorium from a real acidic leach liquor solution under obtained conditions resulted in the production of thorium oxide precipitate with a purity of 66%.

In this research, gas sweetening process of the Iraq Majnoon refinery plant and its optimization scenarios were investigated using ASPEN HYSYS 8.4 and genetic algorithm optimization. First, values of optimization parameters such as the values of the population, generations and crossover for single and multi-objective optimizations were obtained. The effect of temperature and molar flow of feed gas and make-up water on concentration of CO2 and H2S in the sweet gas were studied. The result showed that with increasing the temperature and molar flow of feed gas, the concentration of CO2 and H2S in the sweet gas was increased. The single and multi-objectives’ optimizations of process were carried out with minimizing the concentration of CO2 and H2S, minimizing the consumed energy of stripper and overall consumed energy of plant including energy of stripper and cooler. It was observed that for optimization of concentration of CO2 and H2S, mole fraction of CO2 and H2S decreased to minimum amounts of 5.52 e-4 and 6.84 e-9 between optimization data sets. Also, it was found that with increasing the number of objective functions of the optimization, the ability of the algorithm to reduce the amount of the objective functions decreases, because genetic algorithm should consider more constraints with increasing the number of objective functions. The novelty of this research was a comprehensive study of gas sweetening process optimization with single to four objectives.

This paper reports the results of experimental removal process of ammonia from synthetically prepared ammonia solution using a microscale mixing loop air stripper. Effects of various operational parameters (such as pH, air flow rate, wastewater flow rate, and initial ammonia concentration) were evaluated. By increasing pH from 10 to 12. 25, the amount of KLa increased from 0. 26 to 0. 73 h-1. Considerable enhancement, about 150 %, can be found for KLa by changing the air flow rate from 280 to 700 mL/min under a fixed condition. The wastewater flow rate can also increase the value of KLa from 0. 22 to 0. 59 h-1. The values of KLa increased only about 20 %by changing the initial concentration of ammonia in the range between 50 and 500 mg/L. The results showed that any improvement concerning air stripping using microchannel was successfully carried out with enhancing the overall volumetric mass transfer coefficient (KLa) and providing higher mass transfer capabilities compared with other types of strippers, even for lower amounts of used air. The enhancement of mass transfer takes place by efficient mixing induced by the employed microchannel. It has been demonstrated that wastewater flow rate and air flow rate have significant effects on KLa. The optimal stripping conditions and mathematical modeling for ammonia removal and the relation between the parameters were determined using Response Surface Methodology (RSM) with Central Composite Design (CCD) method. The results demonstrate the advantages the proposed system possesses over conventional stripper types.