一种复合有机缓蚀阻垢剂的室内研究

研究了一种复合有机缓蚀阻垢剂对A3碳钢的缓蚀阻垢性能。挂片失重法测定腐蚀速率,并采用正交实验优化了药剂各成分间的质量比。采用极化曲线和交流阻抗谱研究了不同药剂浓度和80 mg/L药剂质量浓度条件下分别改变溶液pH值、Ca2+、Cl-、HCO3-浓度A3碳钢的腐蚀行为。室内静态阻垢实验研究了该缓蚀阻垢剂在溶液浓缩过程中的阻垢性能,并讨论了造成结垢的主要水质指标变化规律。     

荧光标记无磷缓蚀阻垢剂(PESA-X)的制备及其性能研究

针对绿色环保的无磷缓蚀阻垢剂无法用常规总磷检测方法监测的问题,为了实现对循环冷却水系统中的有效无磷缓蚀阻垢剂含量的实时检测与控制,将无磷缓蚀阻垢剂PESA与荧光示踪剂CBS-X按照一定比例复配制备荧光标记无磷缓蚀阻垢剂(PESA-X)。采用荧光光谱法和碳酸钙沉积法来研究PESA-X的性能,同时还建立以荧光强度为指标的动态阻垢模型。结果表明,PESA-X的荧光强度与其质量浓度呈正线性相关,其线性拟合方程为Y=18.805 X-5.26,R^(2)=0.9997。且PESA的阻垢性能基本没有受到荧光示踪剂CBS-X影响。PESA-X的稳定性良好,受pH、温度、光照时间等因素影响较小。通过动态阻垢实验可知,荧光强度(Y)与Ca^(2+)质量浓度(X)的线性方程为Y=2052.38X-198.20,表明了荧光示踪剂CBS-X与PESA同步消耗。因此,通过对PESA-X的荧光强度分析可以实时显示水处理系统内无磷缓蚀阻垢剂PESA的含量,从而实现用荧光强度定量循环水系统中无磷缓蚀阻垢剂PESA的有效质量浓度,为工业循环冷却水系统实时检测与控制无磷缓蚀阻垢剂的含量提供理论基础。     

电厂循环冷却水处理方案试验

实验研究了阻垢剂HEDP、EDTMPS、PBTCA、DTPMPA、ATMP、PAPEMP在电厂循环水中的应用.通过实验筛选出具有良好处理功效的复合配方:ATMP6mg/L、DTPMPA 4 mg/L、PBTCA 3 mg/L,相应的阻垢率达到92.42%.该复合配方在阻垢性能方面存在协同效应,使得复配处理剂具有良好的阻垢效果.     

三种改性淀粉的制备及其缓蚀阻垢性能比较研究

通过对已有的缓蚀阻垢剂的研究和使用现状进行分析,总结其中存在的不足,并从经济角度考虑出发,将原料易得的马铃薯淀粉进行改性,分别制得双醛淀粉(DAPS)、羧基化淀粉(CPS)与氧化磷酸化淀粉(OPPS),并对3种改性淀粉的静态缓蚀性能及阻垢性能进行比较研究,研究表明,CPS和OPPS都具有良好的阻垢性能,但受温度影响较明显;在相同条件下,OPPS、CPS相对于DAPS而言,对碳钢和黄铜的缓蚀性能更好.     

生活饮用水阻垢剂硅磷晶阻垢性能的实验研究

采用静态阻垢法对硅磷晶阻垢剂的阻垢性能进行分析,通过单因素与正交试验探讨了阻垢剂在不同加药浓度、Ca2+浓度、温度、p H等环境条件下的阻垢效果及最佳使用条件。结果表明:阻垢效果最佳组合为:加药浓度2 mg/L,Ca2+浓度300 mg/L,温度30℃,p H=8。各因素对阻垢率影响大小顺序依次为:温度加药浓度p HCa2+浓度。在此优化组合条件下,硅磷晶阻垢率最大可达95%,用于某制药厂生活饮用水的阻垢率可达94%,效果明显,具有良好的阻垢性能。     

新型低磷循环冷却水缓蚀阻垢剂的实验室研究

在实验室合成绿色无磷阻垢剂聚环氧琥珀酸(PESA),进行结构表征与性能测试,表明合成产物有较好的阻垢性能。将聚环氧琥珀酸与氨基三亚甲基膦酸(ATMP)、羟基亚乙基二膦酸(HEDP)进行复配的试验表明,在投加质量浓度分别为25,15,10 mg/L时,能达到理想的缓蚀阻垢效果。对复配药剂阻垢机理的探讨表明,药剂分子的螯合和分散作用改变了碳酸钙的晶型,一定程度上阻止了垢的沉积。     

阻垢剂在矿井水阻垢处理中的应用

将阻垢剂应用到矿井水阻垢处理中,在原水总硬度为700mg/L(以CaCO3计)时,通过实验确定最佳阻垢剂组合为ATMP∶PAA=1.4 mg/L∶ 1.4 mg/L,阻垢率可以达到98.2％,从而有效地解决了输水管道内侧结垢的问题.     

吉林油田注水系统结垢机理分析及适宜阻垢剂研究

吉林油田注水系统管线结垢严重,影响正常生产安全.为了解决结垢问题,对吉林油田注入水和结垢产物进行了分析,并给出了防护对策.结果表明:吉林油田注入水含有大量的HCO3-,Ca2+含量较其他成垢离子含量高;结垢产物主要是CaCO3垢,另有部分MgCO3垢、硅铝酸盐垢和铁垢,垢样具有明显的有机物包裹特征.在此基础上运用化学溶度积和化学反应方程式直观地表示了吉林油田注水系统的结垢机理.吉林油田注入水中碳酸盐的浓度积远大于其溶度积,导致大量碳酸盐析出结垢.注入水中携带有黏土,在管壁沉积形成硅铝酸盐结垢.铁腐蚀导致吉林油田注水系统产生少量铁垢.最后通过室内静态防垢性能测定法从3种常用缓蚀阻垢剂中筛选出适合吉林油田现场水质防腐阻垢的TH-907型缓蚀阻垢剂,在TH-907药剂质量浓度为50 mg/L时,阻垢效果最好.     

炉内水处理药剂

锅炉内水处理药剂在进行炉内化学处理时,可起到阻垢、防蚀和脱垢的作用。使用这种药剂,操作简便,只需向炉内加入少量(几个ppm),无需增添新设备,即可达到目的。 阻垢剂 阻垢剂一般应具备以下特性。(一)为水溶性物质;(二)耐热性要好;(三)不引起腐蚀,最好本身兼具缓蚀性;(四)不起沫,不发生汽水共腾,最好本身有消沫作用;(五)不会增加炉水含盐量、排污量和排污次数,不会增加热损失与能耗;(六)不过分增加炉水碱度,不致引起碱脆;(七)阻垢效率高,低剂量使用有高阻垢率;(八)价廉,易得;(九)无毒。 国外应用的阻垢剂大多数是混合物。它由沉淀剂、吸附分…     

桑树杆活性炭/铁锰氧化物复合吸附剂对磷的吸附研究

采用原位合成法制备桑树杆活性炭/铁锰氧化物复合吸附剂(MSAC/Fe-Mn),用红外光谱、X射线衍射等对其表征,探讨MSAC/Fe-Mn对磷的吸附机理。研究pH值、吸附时间、初始浓度、温度和共存离子等因素对吸附效果的影响,结果表明,pH值为5时,其对磷的去除效果最好;共存离子对磷的吸附影响大小顺序为CO2-3 SO2-4 NO-3;随着离子强度由0. 05 mol/L(Na NO3)增大到0. 50 mol/L,复合吸附剂对磷的去除率降低了40. 6%;准二级动力学模型较好反映了吸附过程,Langmuir等温吸附模型适合拟合MSAC/Fe-Mn对磷的吸附,在温度为25,35,45℃时,其对磷的最大吸附量分别为16. 26,17. 78,20. 82 mg/g。MSAC/Fe-Mn吸附磷的机制包括静电、离子交换、物理-化学吸附等,MSAC/Fe-Mn中铁锰氧化物和其表面羟基和酚羟基均参与了吸附反应。     

PAN dust explosion inhibition mechanisms of NaHCO3 and Al(OH)3

We investigate the PAN dust explosion inhibition behaviors of NaHCO₃ and Al(OH)₃ in a 20 L spherical explosion system and a transparent pipe explosion propagation test system. The results show that, in the standard 20 L spherical explosion system, the highest PAN dust explosion concentration is 500 g/m³, the maximum explosion pressure is 0.661 MPa, and the maximum explosion pressure increase rate is 31.64 MPa/s; adding 50% NaHCO₃ and 60% Al(OH)₃ can totally inhibit PAN dust explosion. In the DN0.15 m transparent pipe explosion propagation test system, for 500 g/m³ PAN dust, the initial explosion flame velocity is 102 m/s, the initial pressure is 0.46 MPa, and the initial temperature is 967 °C; adding 60% NaHCO₃ and 70% Al(OH)₃ can totally inhibit PAN dust explosion flames. Through FTIR and TG analyses, we obtain the explosion products and pyrolysis patterns of the explosion products of PAN dust, NaHCO₃, and Al(OH)₃. On this basis, we also summarize the PAN dust explosion inhibition mechanisms of NaHCO₃ and Al(OH)₃.     

苯酚对生物硝化过程的抑制

硝化细菌由于其特殊的生理生态特性,容易受环境因素和共存有毒有害物质的影响,使硝化过程不稳定,脱氮效率降低.采用批式试验,研究了苯酚对生物硝化过程的抑制效应.结果表明,苯酚对硝化有抑制作用,该抑制属非竞争性抑制,是可逆的.苯酚与2,4-二氯酚共存时产生叠加抑制效应.且抑制剂存在时,温度对硝化速率影响更大.因此含酚废水生物脱氮处理时需引起注意.     

Wire-mesh inhibition of jet fire induced by explosion venting

Explosion venting is widely applied in industrial explosion-proof designs due to the convenient, economical and practical features of this method. Natural gas is usually stored in storage tanks. If the gas in the vessel is mixed with air and encounters an ignition source, explosion venting might occur, producing jet fire, generating new secondary derivative accidents and causing casualties and property losses. In this paper, a set of test platforms including wire-mesh suppression devices is established to study the inhibition of jet fire induced by explosion venting by wire mesh. The experimental research shows that a wire mesh significantly inhibits the jet fire induced by explosion venting. The flame propagation velocity and pressure clearly decrease with increasing numbers of wire-mesh layers. The wire-mesh structure significantly affects the flame propagation, and the more layers of mesh there are, the better the suppression effect is. The flame temperature gradually decreases with the addition of the wire mesh. The mesh size significantly affects the pressure propagation of explosion venting. The explosion pressure gradually decreases with the addition of the wire mesh. With increasing distance between the wire mesh and the explosion vent, the maximum temperature first increases and then decreases, and the maximum explosion pressure first decreases and then increases. In the case of single gas cloud, the flame suppression effect is the most obvious when the wire mesh is 0.2 m away from the explosion vent. In the case of double gas clouds, the flame suppression effect is the most significant when the distance between the wire mesh and the first gas cloud is 0.4 m.     

污染环境重金属酶抑制法快速检测技术研究进展

综述了酶抑制法快速检测环境重金属的原理和方法,介绍了脲酶抑制法及其与之相结合的酶传感器、试剂条、量热计、比色法等痕量重金属快速检测新技术,提出了今后的研究方向.     

碳酸氢钠及其固态分解产物对玉米淀粉爆炸抑制实验研究*

为研究NaHCO3对玉米淀粉爆炸的抑制效果,采用20 L球形爆炸装置测试玉米淀粉在添加不同抑制比NaHCO3及其固态分解产物Na2CO3后爆炸参数变化规律,并分析NaHCO3抑制淀粉爆炸过程。结果表明:NaHCO3及Na2CO3对玉米淀粉爆炸均有抑制作用,NaHCO3抑制效果优于Na2CO3;混合粉尘的最大爆炸压力、最大爆炸压力上升速率与爆炸指数随抑制比增大而逐渐减小,爆炸时间随抑制比增大而逐渐延长。随着NaHCO3浓度增加,物理抑制效果逐渐增加,化学抑制效果基本保持不变。NaHCO3浓度不同时,其抑制主导过程不同,当抑制比为0.1~0.5时,NaHCO3抑制效果以化学抑制为主,物理抑制为辅;抑制比为0.8和1.2时,NaHCO3抑制效果以物理抑制为主,化学抑制为辅;当抑制比为1.2时,玉米淀粉爆炸完全被NaHCO3抑制,此时物理抑制起主导作用。     

Experimental study on explosion inhibition by heptafluoropropane and its synergy with inert gas

The inhibition effect of heptafluoropropane (CF₃CHFCF₃) on methane explosions under different inhibitor concentrations in a closed vessel was studied. A high-speed camera and a pressure sensor were adopted respectively to record flame propagation characteristics and pressure data. Results indicate that the relationship between flame propagation and pressure rising was correlated. As the equivalent ratio (ϕ)≤1, the pressure presented a trend of rising firstly and then decreasing with increasing CF₃CHFCF₃ concentration, and it was found that there existed a critical concentration for pressure decrease. As ϕ > 1, the pressure exhibited a decreasing trend. Although the pressure appeared to seemingly increase, the moment that the pressure began to rise (t_rise) and the moment that the maximum explosion overpressure appeared (t_Pmax) were obviously delayed. The average rate of pressure rise ((dP/dt)_ave) was decreased as the concentration of CF3CHFCF3 increased. It indicates that CF₃CHFCF₃ can effectively reduce the explosion reaction rate. The critical concentration of CF₃CHFCF₃ for complete inhibition was determined. Meanwhile, the synergy of CF₃CHFCF₃-inert gas can improve the inhibition effect. Compared with CF₃CHFCF₃–N₂, the synergy of CF₃CHFCF₃–CO₂ presented a better inhibition effect, and the inhibition effect was increased with increasing inert gas concentration. And the mechanisms of physical and chemical effects on explosion inhibition were analyzed.     

Experimental study on the synergistic inhibition effect of nitrogen and ultrafine water mist on gas explosion in a vented duct

In this study, in order to research the synergistic inhibition effect of nitrogen and ultrafine water mist on gas explosion in a vented duct, a semi-confined transparent chamber was designed with the size of 120 × 120 × 840 mm, and the experiments were carried out with stoichiometric methane/air premixed mixture (fraction of methane: 9.5%), adding different fractions of nitrogen and ultrafine water mist. The experimental results showed the following: The combination of nitrogen and ultrafine water mist had a synergistic inhibiting effect on methane/air explosion, which was preferable to the single use of any kind. With the increase of spraying time of water mist and fraction of nitrogen, the initial shape of the explosion flame became snakelike, and at the same time the peak flame propagation speed and peak overpressure decreased significantly. When the nitrogen fraction was increased to 10% and the mist spraying time was increased to 2min, synergistic inhibiting effect on overpressure was high efficient. However, with the increase of spraying time of water mist and fraction of nitrogen going on, the amount of increase of explosion inhibition efficiency was gradually reduced.     

超细水雾对管内丙烷爆炸火焰抑制效果的试验研究

利用自行研制的超细水雾抑制管内丙烷爆炸的小尺寸试验系统,研究超细水雾抑制管内丙烷爆炸的有效性.试验采用0.6m×0.09m的圆柱形透明玻璃管,研究体积分数为2.7％～3.7％的丙烷/空气预混气体在0～2 mL超细水雾作用下的爆炸火焰传播特性,测定超细水雾作用下丙烷爆炸下限及火焰传播速度的变化规律,探讨超细水雾对管内丙烷爆炸火焰的抑制机理及效果.结果表明:超细水雾可显著提高丙烷的爆炸下限,降低丙烷爆炸的危险性;超细水雾可有效抑制丙烷爆炸的传播速度,且随超细水雾添加量增大,传播速度不断降低;根据抑制率计算结果,在贫燃料情况下,超细水雾对丙烷爆炸的抑制效果随雾量增大和体积分数降低而增强.     

氯化镁微胶囊泡沫作用机理及阻化效果研究

针对现有硫化矿石自燃防治技术在应用中存在的不足,提出了采用氯化镁微胶囊泡沫防治硫化矿石自燃火灾的新思路。首先阐述了氯化镁微胶囊泡沫的特性与作用机理,然后通过实验,制备了微胶囊与微胶囊泡沫并以正交试验确定了制备微胶囊泡沫的最佳配方:微胶囊与水质量比为1∶5、ABS浓度为6 g/L、稳泡剂X浓度为6 g/L;最后采用对照实验,以温度与阻化率为优选依据,对氯化镁微胶囊泡沫、氯化镁溶液与水三者的阻化效果进行比较。结果表明在氯化镁微胶囊泡沫的作用下,硫化矿石堆的温度上升最慢,阻化率最高,达到81.6%,阻化效果优于其他两种阻化剂。