Key Engineering Materials Vol. 814

Abstract: A large amount of foreign matter appears in the Sulige gas well, causing blockage and corrosion of the pipeline, increasing the pressure difference in the wellbore and seriously affecting the normal production of the gas well. The gas wells with serious conditions mentioned above were selected to analyze the quality of single well produced water and the composition of blockage and core. Combined with the XRD analysis results of the cuttings, the long-term leaching experiments on the cuttings in different simulated solutions were carried out to study the sources of scaled ions in the gas wells. The experimental results showed that the extracted water from SD6-1 had high salinity and high content of scale ions Ca²⁺, Ba²⁺ and Sr²⁺;the main component of blockage is the acid insoluble strontium sulfate (barium) scale, and contains a small amount of corrosion products. The easily scalable Ca²⁺、Mg²⁺、Ba²⁺ and Sr²⁺ produced from the dissolution of the core in the formation water or working fluids, especially the acid erosion dissolves. According to the scaling mechanism, two kinds of Sr/Ba scale inhibitor were selected. The results showed that the barium II scale inhibitor performance is relatively good, and at the concentration of 40 mg/L, and the scale inhibition rate was more than 95%. The clogging of a single well can be reduced by adding a scale inhibitor.

Abstract: Phosphorus scale inhibitor is a kind of agent which can disperse insoluble inorganic salts in water, prevent or interfere with the precipitation and scaling of insoluble inorganic salts on metal surface, and maintain better heat transfer effect of metal equipment. Sodium triethylenetetramine hexamethylphosphonate (TETHMPS) and tetraethylenepentamine heptagon methylene phosphonic (TEPHMPS) were prepared by one-step synthesis method. The effects of temperature, concentration and mixing ratio on scale inhibition were investigated. The results showed that as the concentration of TETHMPS and TEPHMPS increases, the scale inhibition rate increases. At the same temperature, compared with TETHMPS, TEPHMPS has better scale inhibition performance, and the maximum scale inhibition rate can reach 93.59%. The scale inhibition rate of the synthesized scale inhibitor at 80 °C is better than that at 60 °C. The scale inhibition performance of the compound scale inhibitor is better than that of the single scale inhibitor, showing an ideal synergistic effect. When the concentration is 60 mg/L, the scale inhibition rate of TETHMPS is 94.26%, TEPHMPS is 94.55%, and the scale inhibition rate is above 91%.

Abstract: Compared with bio-oil from sawdust (common lignocellulosic biomass), the bio-oil obtained by fast pyrolysis of coffee waste has a unique feature to contain a significant amount of fatty acids such as oleic acid and palmitic acid. It is necessary to conduct C-C cracking of fatty acids present in coffee-waste bio-oil to maximize gasoline fraction (C₅-C₁₂) production. In this work, catalytic cracking of oleic acid as a model compound for the fatty acids was carried out in batch reactors to understand the effect of major parameters such as zeolite type (HZSM-5, SAPO-11, MCM-41), reaction temperature (380-500 ^°C), and reaction time (0-50 min) on gasoline fraction production. The GC-MS analysis showed hydrocarbons and aromatics to be major compounds present in the gasoline fraction irrespective of zeolite type and reaction conditions. At 400 ^°C and 0 min reaction time, the yield of gasoline fraction was 18.6, 6.7, and 33.1 % with HZSM-5, SAPO-11, and MCM-41, respectively. As reaction temperature increased to 500 ^°C, the total gasoline fraction yield reached 43.7 and 22.7 % with SAPO-11 and MCM-41, respectively. In all the catalysts, the content of aromatic compounds in the gasoline fraction increased with the increase in reaction temperature and reaction time. Meanwhile, the formation of hydrocarbons in the gasoline fraction showed different optimum temperature with catalyst: 11.8 % yield with SAPO-11 at 500 ^°C and 27.0 % yield with MCM-41 at 400 ^°C.

Abstract: The amount of waste produced increases globally, and valuable resources are lost if materials contained in wastes are not recycled. One such important material group is plastics, but it is typically mixed in municipal solid waste. In this paper, the effect of maleic compatibilizer on the melt properties of mixed waste plastic is studied in order to evaluate the effect of compatibilization on the processability of reclaimed plastics. The results indicate, that compatibilization has significant effect on both melt flow rate and melt volume index. Both are decreased notably, suggesting that compatibilization may impair the processability of mixed waste plastic, even though it is expected to improve other properties.

Abstract: Jasminum Subtriplinerve Blume (Oleaceae) is herbal plants widely a tea for weight loss, stimulates milk glands. Extract product it easy used yet had little research. This study was carried out to evaluate the effect of extracting conditions such as water/material ratio, extraction temperature and extracting time on extracting yield, polyphenol content and antioxidant activity of J.subtriplinerve extract. The total phenolic compounds were determined according to the Folin–Ciocalteu method. Extraction yield (0.22g/100 g) was obtained at water/material ratio 15:1 (ml/g), 40°C and 4 hours extraction time. Under these optimized conditions, the polyphenol content of was 2640.4 μg/1g extract. And the extract can harvest 46.11 % of DPPH (30 μg/ mL) at 10 000 μg/ml concentration