安全高效型聚合物降解剂的筛选及优化

聚合物在驱油过程中容易堵塞地层,降低地层渗透率,因此需要利用降解剂对聚合物进行降解,实现解堵目的。本文将降解剂与稳定剂进行复配,研制出一种安全高效的聚合物降解剂。通过降解率以及活性氧质量分数测量优选出氧化物SOU作为降解剂主剂和柠檬酸作为稳定剂,配方为3%氧化物SOU+0. 1%柠檬酸。该体系降解效果高效安全,在油田及矿场具有良好的推广应用价值。     

冻胶型堵剂解堵实验研究

本文针对冻胶型堵剂在油田调剖堵水中的广泛应用，但用冻胶封堵地层会对中低渗透层产生污染的情况，选用了过硫酸铵溶液进行解堵研究，并通过浓度、pH值、矿化度等因素对解堵效果的影响对其进行了评价。从而得到最佳解堵效果的过硫酸铵配方。     

三价铬氧化方法比较研究

三价铬氧化为六价铬、六价铬与二苯碳酰二肼显色是测定水溶液中三价铬含量最常用的方法,该方法的关键是既要方便快捷地将三价铬完全转化为六价铬,同时还要避免氧化剂与显色剂反应干扰测定。通过实验比较了几种文献中报道的三价铬氧化方法,并进行了优化研究。实验结果表明,高锰酸钾、过硫酸铵和过氧化氢都是适宜的三价铬氧化剂,而高氯酸和溴效果不好。综合准确、简便、安全等因素,推荐过硫酸铵和过氧化氢作为首选氧化剂。     

用过氧化氢作氧化剂测定镀铬溶液中的铬(Ⅲ)

提出采用过氧化氢作氧化剂,结合碘量法测定镀铬溶液中的铬(Ⅲ)。对模拟的镀铬液进行了滴定,检验了该方法的可行性与准确性。采用该法、过硫酸铵-高锰酸钾法、过硫酸铵-碘量法3种方法分别对镀铬原液中的铬(Ⅲ)进行了测定与比较。结果表明,过硫酸铵作氧化剂结合碘量法,易产生Ad沉淀,影响精确度;而该法的滴定终点清晰,易于掌握和观察,精确度高,特别适用于镀铬液的现场常规分析,但应注意控制待测液的酸碱度。     

针对高台子X区块注聚井解堵剂配方研制

针对大庆油田聚合物驱造成地层堵塞问题,采用室内物理模型实验,对注聚井进行解堵剂配方研制,筛选出适合的溶蚀剂、洗油剂和降解剂,并确定最佳浓度。实验结果表明;8%HCl+2%HF作为溶蚀剂、0.5%XY-J作为洗油剂和1%超稳氧化解聚剂0.3%BH_1作为降解剂;并通过岩心模拟实验评价其解堵效果明显,可作为现场实施配方,并具有指导意义。     

渤海油田注聚井复合解堵技术现场应用

随着聚合物驱大规模的推广,注聚井堵塞问题越发严重,聚合物溶液不能进入低渗层,层间矛盾加剧,造成驱油效率低下。常规的注聚井解堵技术有效期短,本文通过对注聚井堵塞原因分析入手,研制出由聚合物降解剂、复合酸组成的复合解堵技术,在渤海油田试验成功并得以推广应用。     

胍胶压裂液高效破胶降解剂体系研究

胍胶压裂液是低渗透油藏水力压裂应用最广泛的压裂液体系,针对其破胶不彻底,残渣、残胶易造成压后储层伤害的问题,通过耐温耐剪切性、破胶液黏度、破胶液残渣含量测试实验,从10种破胶剂、9种降解剂中筛选、优化了胍胶压裂液复合破胶降解剂。并利用凝胶渗透色谱仪和激光粒度仪对胍胶压裂液破胶液中聚合物分子量和残渣粒径进行了测试。结果表明,0.06%(质量浓度)破胶剂P4(过硫酸铵∶亚硫酸钠=9∶1,质量比)+0.009%降解剂M2(BAT-2)为最佳复合破胶降解剂体系,其对应胍胶压裂液耐温耐剪切性测试稳定黏度、破胶液黏度、破胶液中残渣含量分别为103 mPa·s, 1.5 mPa·s和202 mg/L。相对于现用过硫酸铵破胶剂,优化的破胶降解剂体系可降低破胶液中聚合物平均分子量16.0%;减小破胶液中残渣粒径中值21.5%。     

桩西疏松砂岩油藏防砂井解堵技术研究

油井防砂后堵塞降产是制约油井开发的难题,分析认为,油井降产的主要原因是有机垢和微粒运移双重堵塞,同时有机垢堵塞和微粒运移堵塞的相互加剧。针对以上难题,开展了解堵及固砂稳砂研究,筛选出了针对性较强的解堵固砂剂。室内实验表明,解堵剂具有较好的解堵和固砂能力。现场应用后,解堵固砂效果明显,增液显著。     

含聚污水回注储层解堵复合添加剂研发

为降低含聚合物污水回注地层后对储层物性的损伤,借助化学分析的方法对含聚污水的成分迚行了深入的分析,从含聚污水造成堵塞的具体原因出収,研制了以氧化剂、表活剂和洗油剂为主要成分的降解剂;为了有效防止污染物沉积于孔道壁面及提升解堵剂的解堵性能,研制了孔道防堵剂和润湿剂;为了能够防堵剂对管线以及井筒造成腐蚀、避免地层中的粘土矿物与解堵剂収生反应,研制了储层解堵复合添加剂。经实验研究収现,配制的含聚污水解堵配方即能够起到良好的作用,对于孔道也有着良好的保护作用,具有一定的推广意义。     

渤海油田注聚井解堵技术研究与应用

聚合物驱油已经成为渤海油田提高采收率的主要技术手段,但是随着聚合物注入量的不断增多,注聚过程中经常出现注入压力过高、无法达到配注量、相应的增产措施效果不明显等问题,影响了聚驱效果。针对上述情况,在对渤海油田注聚井堵塞原因进行了分析和研究后,研发出了适用于渤海油田注聚井解堵的体系和相应的施工工艺,其中协同降解剂对聚合物堵塞的解堵率在80%以上,注入强穿透剂可以提高解堵率最高达1 4.3%,加入孔道保护剂后防堵率最高达到4 1%。现场应用了7井次,取得了良好的降压增注效果。     

Surface oxidation of low‐density polyethylene films to improve their susceptibility toward environmental degradation

Polyethylene wastes, particularly as films, have accumulated over the last several decades resulting in a major visual litter problem. The aim of this study was to investigate the ability of chemical reagents to oxidize the low‐density polyethylene (LDPE) film surface to increase their susceptibility toward photodegradation and thermal degradation. Three chemical agents, namely, potassium permanganate, potassium persulfate, and benzoyl peroxide, were used to oxidize the film surface to generate chromophoric groups, such as carbonyl groups, which are the main reason for the enhanced environmental degradation of photolytic polymers, such as ethylene–carbon monoxide and ethylene–vinyl ketone copolymers. For the chemical treatment, LDPE films of 70 ± 5 μm thickness were prepared by a film‐blowing technique and subsequently reacted with the aforementioned oxidizing agents. To aid the oxidation process, the reaction with potassium persulfate and potassium permanganate was performed under microwave irradiation heating. In the case of benzoyl peroxide aided oxidation, the films were subjected to repeated coating–heating treatments up to a maximum of 10 cycles. The treated films were subjected to accelerated aging, that is, xenon‐arc weathering and air‐oven aging (at 70°C), for extended time periods. The chemical and physical changes induced as a result of aging were followed by the monitoring of changes in the mechanical, structural, and thermal properties. The results indicate that the surface‐oxidized LDPE films exhibited enhanced susceptibility toward degradation; however, the extent was reduced as compared to photolytic or other degradable compositions. The ability of the chemicals to initiate degradation followed the order potassium persulfate < potassium permanganate < benzoyl peroxide. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

氧化剂对钢铁表面氟铁酸盐转化膜的影响

通过中性盐雾试验,研究了过氧化氢、钼酸钠、澳酸钾、碘酸钾和过硫酸铵等氧化剂对Q195冷轧钢表面所形成的氟铁酸盐转化膜耐蚀性的影响.结果表明,氧化剂为过硫酸按时,形成的转化膜效果最好,其质量浓度为7 g/L时,转化膜的耐盐雾时间可达到8h.过硫酸按的加入使氟铁酸盐转化膜的形成加快,形成的无定形结构亦使得膜层耐蚀性能更好.     

不同引发剂引发纤维素和丙烯酰胺接枝共聚的研究

本文研究了硫酸铈铵,硫酸亚铁/过氧化氢,硫脲/过氧化氢,高锰酸钾引发蔗渣微晶纤维素与丙烯酰胺的接枝聚合。通过上述引发剂的比较,发现高锰酸钾是一种优良的引发剂。探讨了高锰酸钾引发微晶纤维素接枝聚合的反应机理。     

The accelerated degradation of aqueous polyacrylamide at low temperature

The accelerated degradation of aqueous polyacrylamide at low temperature was studied. The selected degradation agents included several peroxides, such as potassium persulfate (K₂S₂O₈), ammonium persulfate ((NH₄)₂S₂O₈), hydrogen peroxide (H₂O₂), and the potassium persulfate–sodium thiosulfate (K₂S₂O₈–Na₂S₂O₃) redox system. The redox system showed the highest degradation rate at the first 2 hours, but its final degradation level was lower than that of potassium persulfate. The degradation temperature, concentration of potassium persulfate and polyacrylamide, and original molecular weight of polyacrylamide all affected the degradation rate and final degradation level. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 791–797, 1998     

离子液辅助制备二氧化锰及催化性能研究

以高锰酸钾和三乙醇胺型离子液为原料合成了二氧化锰,采用X射线衍射技术和扫描电子显微镜考察了二氧化锰的相组成和形貌,并以酸性品红为降解对象考察了二氧化锰的催化性能。结果表明：催化剂的加入量,双氧水的加入量,pH值和焙烧温度对于催化剂的降解活性都有显著的影响,酸性品红降解的最佳条件为：0.05 g的二氧化锰,pH等于7,双氧水的加入量为2 mL。实验还表明催化剂高温煅烧后活性会下降。     

木素磺酸钙的氧化改性研究

研究了木素磺酸钙 (简称木钙 )的氧化改性工艺 ,比较了几种氧化剂与木钙反应后性能的差异。结果表明 ,过氧化氢对木钙的聚合或降解作用均较弱 ,过硫酸铵在适宜的条件下可使木钙发生聚合反应 ,并显著改善木钙的表面物化性能。过硫酸铵氧化木钙时 ,适宜的氧化条件是过硫酸铵的用量为 4%～ 6 % ,反应温度为 80～ 90℃ ,pH =8～ 10。初步探讨了木钙的氧化聚合机理 ,过硫酸铵在碱性条件下使木钙酚型物发生离子化脱氢 ,产生了游离基 ,从而提高了木钙的反应活性 ,促进了木钙分子游离基之间的聚合反应。     

Investigation of the reaction products of unsymmetrical dimethylhydrazine with potassium permanganate by gas chromatography-mass spectrometry

The gas chromatography-mass spectrometry technique was used to investigate the composition of the reaction products of unsymmetrical dimethylhydrazine with a potassium permanganate and potassium permanganate-hydrogen peroxide mixture. If the water contamination level is within 50 threshold limit values (TLV) (1 mg/ml), the proposed detoxication method utilizing potassium permanganate in combination with hydrogen peroxide allows for the reduction of the UDMH concentration to a safe level without the accumulation of transformation products. The detoxication of aqueous solutions with significant UDMH concentrations (up to 50000 TLV) (1 g/l) with potassium permanganate alone or in combination with hydrogen peroxide reduces the UDMH concentration to a safe level, but UDMH transformation products, including the extremely toxic nitrozodimethylamine, are accumulated in the solution.     

Novel High-Viscosity Polyacrylamidated Chitosan for Neural Tissue Engineering: Fabrication of Anisotropic Neurodurable Scaffold via Molecular Disposition of Persulfate-Mediated Polymer Slicing and Complexation

Macroporous polyacrylamide-grafted-chitosan scaffolds for neural tissue engineering were fabricated with varied synthetic and viscosity profiles. A novel approach and mechanism was utilized for polyacrylamide grafting onto chitosan using potassium persulfate (KPS) mediated degradation of both polymers under a thermally controlled environment. Commercially available high molecular mass polyacrylamide was used instead of the acrylamide monomer for graft copolymerization. This grafting strategy yielded an enhanced grafting efficiency (GE = 92%), grafting ratio (GR = 263%), intrinsic viscosity (IV = 5.231 dL/g) and viscometric average molecular mass (MW = 1.63 × 10⁶ Da) compared with known acrylamide that has a GE = 83%, GR = 178%, IV = 3.901 dL/g and MW = 1.22 × 10⁶ Da. Image processing analysis of SEM images of the newly grafted neurodurable scaffold was undertaken based on the polymer-pore threshold. Attenuated Total Reflectance-FTIR spectral analyses in conjugation with DSC were used for the characterization and comparison of the newly grafted copolymers. Static Lattice Atomistic Simulations were employed to investigate and elucidate the copolymeric assembly and reaction mechanism by exploring the spatial disposition of chitosan and polyacrylamide with respect to the reactional profile of potassium persulfate. Interestingly, potassium persulfate, a peroxide, was found to play a dual role initially degrading the polymers—“polymer slicing”—thereby initiating the formation of free radicals and subsequently leading to synthesis of the high molecular mass polyacrylamide-grafted-chitosan (PAAm-g-CHT)—“polymer complexation”. Furthermore, the applicability of the uniquely grafted scaffold for neural tissue engineering was evaluated via PC12 neuronal cell seeding. The novel PAAm-g-CHT exhibited superior neurocompatibility in terms of cell infiltration owing to the anisotropic porous architecture, high molecular mass mediated robustness, superior hydrophilicity as well as surface charge due to the acrylic chains. Additionally, these results suggested that the porous PAAm-g-CHT scaffold may act as a potential neural cell carrier.     

Decolourisation of dyes and dyehouse effluent in a bubble‐column reactor by ozonation in the presence of H2O2, KMnO4 or Ferral

The decolourisation of aqueous solutions of dyes by ozonation in the presence of hydrogen peroxide, potassium permanganate or Ferral using a bubble column reactor was investigated. Addition of hydrogen peroxide in the ozonation reaction of dyes did not affect its decolourisation efficiency. The addition of potassium permanganate considerably increased the decolourisation efficiency during ozonation of all of the dyes studied. Ferral showed excellent catalytic activity under acidic conditions but in alkaline conditions its catalytic activity diminished. The effect of the ozonation on COD was also monitored and was found to be highly effective in reducing the COD of aqueous dye solutions. In addition to studying the effect of addition of hydrogen peroxide, potassium permanganate or Ferral on the ozonation of aqueous solutions of individual dyes, tests were carried out on effluent from a commercial dyeing unit. Copyright © 2005 Society of Chemical Industry     

玉米淀粉氧化工艺的研究

研究了玉米淀粉的氧化工艺。通过次氯酸钠、过氧化氢、高锰酸钾二次氧化、高碘酸钠氧化的比较,优选了高锰酸钾二次氧化作正交实验。直观分析及方差分析结果表明,最佳的氧化工艺为:氢氧化钠0.6 g,硫酸3 g,淀粉乳浓度40%,高锰酸钾1.2 g。