Startup and operation of anaerobic EGSB reactor treating palm oil mill effluent

A bench-scale expanded granular sludge bed （EGSB） reactor was applied to the treatment of palm oil mill effluent （POME）. The reactor had been operated continuously at 35℃ for 514 d, with organic loading rate （OLR） increased from 1.45 to 17.5 kg COD/（m^3·d）. The results showed that the EGSB reactor had good performance in terms of COD removal on the one hand, high COD removal of 91% was obtained at two days＇ of hydraulic retention time （HRT）, and the highest OLR of 17.5 kg COD/（m^3·d）. On the other hand, only 46% COD in raw POME was transformed into biogas in which the methane content was about 70% （V/V）. A 30-d intermittent experiment indicated that the maximum transformation potential of organic matter in raw POME into methane was 56%. Volatile fatty acid （VFA） accumulation was observed in the later operation stage, and this was settled by supplementing trace metal elements. On the whole, the system exhibited good stability in terms of acidity and alkalinity. Finally, the operational problems inherent in the laboratory scale experiment and the corresponding countermeasures were also discussed.

Removal of phenol by activated carbons prepared from palm oil mill effluent sludge

The study was attempted to produce activated carbons from palm oil mill effluent （POME） sludge. The adsorption capacity of the activated carbons produced was evaluated in aqueous solution of phenol. Two types of activation were followed, namely, thermal activation at 300, 500 and 800%, and physical activation at 150% （boiling treatment）. A control （raw POME sludge） was used to compare the adsorption capacity of the activated carbons produced. The results indicated that the activation temperature of 800℃ showed maximum absorption capacity by the activated carbon （POME 800） in aqueous solution of phenol. Batch adsorption studies showed an equilibrium time of 6 h for the activated carbon of POME 800. It was observed that the adsorption capacity was higher at lower values ofpH （2--3） and higher value of initial concentration of phenol （200--300 mg/L）, The equilibrium data were fitted by the Langmuir and Freundlich adsorption isotherms. The adsorption of phenol onto the activated carbon POME 800 was studied in terms of pseudo-first and second order kinetics to predict the rate constant and equilibrium capacity with the effect of initial phenol concentrations. The rate of adsorption was found to be better correlation for the pseudo-second order kinetics compared to the first order kinetics.

High performance electrocoagulation process in treating palm oil mill effluent using high current intensity application

Electrocoagulation process using high current intensity to treat palm oil mill effluent(POME) was investigated in this study.Various operating parameters such as electrolysis time, inter-electrode distance and initial pH were carried out to determine the efficient process condition on the removal of chemical oxygen demand(COD),biological oxygen demand(BOD) and suspended solids(SS).The highest treatment was achieved at 50 min with the removal efficiencies for COD, BOD and SS obtained as 85%, 83%, and 84%, respectively.More than 50 min treatment showed the fluctuated trends of removal efficiencies which can be considered insignificant.The application of higher current resulted in higher removals of organics while the gas bubbles also assisted in removing the pollutant particles by floatation.In an inter-electrode distance study, the removal efficiency decreased when inter-electrode distance was either higher or lower than 10 mm due to the increase of solution resistance and the decrease of anode active surface area.In initial pH study, it was found that high removal efficiencies were achieved in slightly acidic POME sample rather than in neutral or basic condition.An electrocoagulation process by using the optimum operating parameters was able to remove COD, BOD and SS up to 95%, 94% and 96% respectively.The experimental results confirm that application of high current intensity in electrocoagulation provided high treatment efficiency at a reduced reaction time.

Integration of biological method and membrane technology in treating palm oil mill effluent

Palm oil industry is the most important agro-industry in Malaysia, but its by-product-palm oil mill effluent （POME）, posed a great threat to water environment. In the past decades, several treatment and disposal methods have been proposed and investigated to solve this problem. A two-stage pilot-scale plant was designed and constructed for POME treatment. Anaerobic digestion and aerobic biodegradation constituted the first biological stage, while ultrafiltration （UF） and reverse osmosis （RO） membrane units were combined as the second membrane separation stage. In the anaerobic expanded granular sludge bed （EGSB） reactor, about 43% organic matter in POME was converted into biogas, and COD reduction efficiency reached 93% and 22% in EGSB and the following aerobic reactor, respectively. With the treatment in the first biological stage, suspended solids and oil also decreased to a low degree. All these alleviated the membrane fouling and prolonged the membrane life. In the membrane process unit, almost all the suspended solids were captured by UF membranes, while RO membrane excluded most of the dissolved solids or inorganic salts from RO permeate. After the whole treatment processes, organic matter in POME expressed by BOD and COD was removed almost thoroughly. Suspended solids and color were not detectable in RO permeate any more, and mineral elements only existed in trace amount （except for K and Na）. The high-quality effluent was crystal clear and could be used as the boiler feed water.

A Study on Zeolite Performance in Waste Treating Ponds for Treatment of Palm Oil Mill Effluent

Oil palm currently occupies the largest acreage of farm land in Malaysia. In 2011, the production of palm oil in Malaysia was recorded as 19.8 million tons which has led to a huge amount of wastewater known as palm oil mill effluent (POME). This work focuses on the ponding system which acts as wastewater treatment plant in order to treat POME. The conventional ponding system applied in mills consists of a series of seven ponds. The maintenance costs of the pond are expensive thus study of alternative methods is needed. POME treatment using zeolite shows a potential to overcome the problem. Samples collected from selected ponds are tested and analyzed using water analyzer method. Result from adsorption by zeolite shows a significant reduction of COD, BOD, Fe, Zn, Mn and turbidity. This shows that zeolite is highly potential to be applied as adsorbent in the POME treatment plants. The results here may lead to lower maintenance cost, lower quantity of treatment ponds and lesser land occupied for the treatment of POME in Malaysia.

Biochemical Characterization of Lipase Produced by <i>Bacillus</i>spp. Isolated from Soil and Oil Effluent

The aim of the present work was to isolate Bacillus spp. With high lipase activity;to characterize the isolates using both biochemical and molecular methods;to produce lipase using Bacillus isolates and to study the biochemical and biophysical characteristics of the produced lipase. Sixty five Bacillus isolates were isolated from soil 20 isolates from guar field soil (G), 15 isolates from Abusabein field soil (B), 15 isolates from sun flower field soil (S) and 15 isolates from oil effluent (O). Lipase producing isolates were screened;a Chromogenic plate’s method was used. Enzyme activity was quantitatively assayed. Lipase production under submerged fermentation (SMF) conditions using a production medium that contained metal salts, Tween-20 and olive oil as substrate at different period 24, 48, 72 and 96 h, the optimum pH, temperature for lipase activity was determinated and kinetics as well. The isolates showed the highest lipase activity which was identified as Bacillus sp. The optimum pH, temperature, thermostability and kinetic of the produced enzymes were found in three isolates G14, O1 and B10 with the highest enzyme activity and best stability. The isolates G14, O1 and B10 revealed the highest lipase activity of 63.4, 41.2 and 28.3 U/ml, respectively. The results showed optimum pH of the lipase activity from isolates G14, O1 and B10 8.0, 6.0 and 6.0 and the optimum temperature 40, 60 and 75˚C, respectively. Lipase enzymes from isolates O1 and B10 were found to be more thermostable after incubation time for 120 min at 90˚C. The Vmax and Km values of lipase for isolates G14, OI and B10 were 17.6, 135 and 24.4 μmole∙min−1 and 1.3, 1.6 and 0.681 mM, respectively. According to these results Bacillus spp. with high lipase activity and thermostability can be used to promote food, pharmaceuticals, paper, detergents agrochemicals industries and pollution control in Sudan.

Comparison of ASBR and CSTR reactor for hydrogen production from palm oil mill effluent under thermophilic condition

Hydrogen production from palm oil mill effluent (POME) by Thermoanaerobacterium thermosaccharolyticum PSU-2 was investigated both in batch and continuous reactors using anaerobic sequencing batch reactor (ASBR) and continuous stirred tank reactor (CSTR). The hydrogen production determined from batch experiment of POME at an inoculum size of 0%, 10%, 20% and 30% (v/v) was 161, 201, 246 and 296 mL H2/g-COD with COD removal efficiency of 21%, 23%, 23% and 23%, respectively. Continuous hydrogen production was start-up with 30% (v/v) inoculum in both ASBR and CSTR reactors and more than 30% COD removal could be obtained at HRT of 4 days, corresponding to OLR of 11.3 g COD/ L·day. Similar hydrogen production rates of 2.05 and2.16 LH2/L. day were obtained from ASBR and CSTR, respectively. COD removal efficiency of ASBR was 37.7%, while it was 44.8% for CSTR. However, ASBR was stable in term of alkalinity, while the CSTR was stable in term of hydrogen production, soluble metabolites concentration and alkalinity. Therefore, the CSTR was found to be more stable in hydrogen production than ASBR under the same OLR.

Isolation of Bacteria with Purifying Potential and Application in the Treatment of Effluents from an Artisanal Palm Oil Mill in the Littoral Region of Cameroon

It is with the aim of solving the problem of generating large quantities of effluents from palm oil production in the littoral region of Cameroon that this study was carried out with the general objective of reducing the pollutant load of these effluents by using bacteria. To this end, raw palm oil mill wastewater samples were taken for their characterization by evaluating the in-situ (Temperature, pH and (CND) Conductivity) and ex-situ (SS (suspended solid), COD (chemical oxygen demand), BOD (biological oxygen demand) and O/F (oil and fat)) parameters. In addition, bacterial isolation and screening were carried out from samples of contaminated soil based on the production of lipolytic enzymes, the degradation of oils and fats and the reduction of the pollutant load. Results revealed that 28 isolates were able to reduce the pollution parameters of palm oil mill effluents of which D17, D22 and D23 seemed to be the best purifying isolates. The characterization of the POME (palm oil mill effluent), basing the temperature, pH, CND, O/F, SS, BOD and COD showed us values greater than the recommended rate. Partial characterization of these isolates revealed that D17 and D23 are bacteria that could reduce the polluting parameters of the effluents belonged to the Bacillus sp. genus and D22 to the Acinetobacter sp. genus. These results are satisfactory and the bacteria strains obtained could be used in bioremediation.

Utilization of Mill Effluent for Growth, Availability and Uptake of Nutrients by Palm Oil Seedlings

A large amount of palm oil mill effluent is one of the issues faced by palm oil producers in Indonesia. To alleviate the environmental pollution, it is necessary to reduce the problem by using it as a liquid organic fertilizer. A pot experiment to determine the effects of mill effluent on growth of palm oil seedlings （Elaeis guineensis Jacq.）, availability and uptake of macronutrients was conducted in Tandun Plantation Unit, province of Riau, Indonesia. The experiment used a randomized block design, consisting nine combinations of mill effluent doses （3.2, 6.4 and 9.6 L） and recommended fertilizer doses （100%, 75%, 50% NPKMg） in 20 kg soil and one control. The experiment was replicated three times. The results showed that plant height, stem diameter and number of fronds of palm oil seedlings at 26 weeks after planting （WAP） were significantly affected by application of 9.6 L mill effluent with 50%-75% NPKMg, The enhancement of soil organic C （Co,g） content, soil pH and cation exchange capacity due to the application of 9.6 L mill effluent combined with 50% NPKMg caused the availability of soil P and total N （Ntot） increased significantly, while exchangeable K was affected by application of 6.4 L mill effluent combined with 100% NPKMg. All treatments did not affect soil exchangeable Mg. A positive correlation between availability of soil N, P, K and its uptake by palm oil seedlings at 26 WAP were indicated by r = 0.61, 0.63 and 0.57, respectively.

Overview on Application of Response Surface Methodology （RSM） in Treatment of Palm Oil Mill Effluent （POME）

There are many factors affecting the performance of a treatment system especially in the treatment of palm oil mill effluent （POME） as its contains high amounts of suspended solid, low pH, high salt content and high chemical oxygen demand （COD）. However, one factor at a time approach is complicated method in establishing relationship between multiple parameters. Response surface methodology （RSM） is a recommended approach as it is widely used to analyze and study the interactions between multiple parameters and provides optimum output as well as minimizing the defects which result in good treatment system. This paper overviews the recent and current research in the application of RSM in optimizing the treatment development of POME.

Di(2-ethylhexyl) phosphoric acid-coconut oil supported liquid membrane for the separation of copper ions from copper plating wastewater

Permeation of Cu（Ⅱ） from its aqueous solution through a supported liquid membrane （SLM） containing di（2-ethylhexyl）phosphoric acid （D2EHPA） carrier dissolved in coconut oil has been studied. The effects of Cu（Ⅱ）, pH （in feed）, H2SO4 （stripping） and D2EHPA （in membrane） concentrations have been investigated. The stability of the D2EHPA-coconut oil has also been evaluated. High Cu（Ⅱ） concentration in the feed leads to an increase in flux from 4.1 × 10^-9 to 8.9 × 10^-9 mol/（m^2·s） within the Cu（Ⅱ） concentration range 7.8×10^-4-78.6×10^-4 mol/L at pH of 4.0 in the feed and 12.4 × 10^-4 mol/L D2EHPA in the membrane phase. Increase in H2SO4 concentration in strip solution leads to an increase in copper ions flux up to 0.25 mol/L H2SO4, providing a maximum flux of 7.4 × 10^-9 mol/（m^2·s）. The optimum conditions for Cu（Ⅱ） transport are, pH of feed 4.0, 0.25 mol/L H2SO4 in strip phase and 12.4 × 10^-4 mol/L D2EHPA （membrane） in 0.5 μm pore size polytetrafluoroethylene （PTFE） membrane. It has been observed that Cu（Ⅱ） flux across the membrane tends to increase with the concentration of copper ions. Application of the method developed to copper plating bath rinse solutions has been found to be successful in the recovery of Cu（Ⅱ）.

Aerobic Degradation Process in Palm Oil Mill— Issues, Challenges and Upsurging Its Efficiency through Bioremediation

Palm oil mill effluent (POME) is liquid waste produced from palm oil extraction process. Discharging it to the river without treatment is violation according to Malaysia Environment of Quality Act (EQA) 1974. In Malaysia, ponding system is a conventional treatment method for POME due to its economical and simple process. The treatment process mainly involves two main treatment phases;anaerobic and aerobic degradation. Anaerobic degradation has a proven track record in reducing pollutant properties in POME up to 85%. The real challenge is to increase the efficiency of aerobic process as the biological oxygen demand (BOD) discharge limit has been further reduced from 100 mg·L-1 to less than 20 mg·L-1. One of economical and feasible approach to increase the efficiency of aerobic phase is via bioremediation. This paper describes the limitation of aerobic degradation in ponding system, besides discussed on the important aspects that need to be optimized for a success implementation of bioremediation and its challenges.

Using Nonconventional Water in Irrigation of Olive Trees and Its Effect on Olive Oil Properties

The response of olive orchard with same age and type to irrigation with treated municipal wastewater and freshwater was investigated in three years. Physical and chemical properties of the treated municipal wastewater reuse in agriculture (the effluent) produced by the Sheikh Ejleen wastewater treatment plant in Gaza Strip, freshwater, soil, and olive oil were determined and compared with Palestinian and international standards. The biological oxygen?demand (BOD) of Sheikh Ejleen effluent is 60 mg·l-1, which indicates low quality effluent. The results indicate that most of olive oil quality parameters—including heavy metals and trace elements for both fruits irrigated with treated wastewater or irrigated with freshwater—fall within the acceptable standard limit values. Moreover, soil analysis shows that organic content and cation exchange capacity were improved in soil irrigated with treated wastewater in comparison with that irrigated with freshwater. The results also show that there is no trace elements or heavy metals accumulation in soil.

驱油用阴离子表面活性剂的识别与检测方法研究

针对油井采出液中复杂离子条件下驱油用阴离子表活剂难以检测的问题,利用高效液相色谱系统,建立了油田产出液中驱油用阴离子表面活性剂的识别与检测方法,并验证了方法的准确性与有效性。该方法具有快速准确、操作简便、适用性强的特点。确定了表面活性剂从油田产出液(包括原油和污水)中分离的方法,矿场应用效果较好,为油田驱油用阴离子表面活性剂的矿场测试提供技术支持。

俄罗斯难采石油及税收优惠研究

俄罗斯剩余石油储量中,难采石油储量占比不断上升。目前俄罗斯没有统一的难采石油划分标准,既有专业技术指标的划分,也有税法规定的相关标准。开发难采石油是现今俄罗斯油气行业面临的主要问题。俄罗斯主要的难采石油包括低渗透储层、高粘度、边远地区、高采出程度等不同种类。为了激励难采石油储量开发,俄罗斯政府从2005年开始制定了矿产开采税税收优惠政策,在2014年以统一的公式纳入石油开采税计算公式。为了进一步鼓励俄罗斯油气产业投资和新技术开发利用,从而激励难采石油的开发和资源替代升级,引入了额外收入税制度,从2019年起在部分未开发区块或老油田试点实施。自实施税收优惠政策以来,俄罗斯难采石油产量快速增长,未来其石油产量的稳定也将主要依靠难采石油的增产。俄罗斯是中国对外油气战略合作区之一,难采石油储量的勘探开发是未来中俄油气合作重要领域。

多层砂岩油田热采油藏管理提高采收率

概述了美国科恩河油田多层砂岩稠油油藏的特征和开发历史,重点讨论了强化热采油藏管理提高采收率的实践。科恩河油田为水动力圈闭的单斜油藏,蒸汽驱开采后期,碳氧比能谱测井、四维时移热采动态及注采井动态监测结果,孤立单河道砂体识别、追踪,全油田三维地质建模及数值模拟研究为识别剩余油和提高采收率提供了依据。人工智能、蒸汽泡沫驱、双油管完井分层注蒸汽等措施扩大了蒸汽驱波及体积。加密井、水平井钻井及浅部油藏侧钻水平井可大幅度增加可采储量,水平井产量达到相邻直井的3倍以上。为开采油藏下倾部位油水界面附近未动用的“冷油藏”,在下倾部位水层钻产水井泄压,使蒸汽驱得以有效波及到该部位剩余油。

气凝胶在稠油热采井水泥浆中的应用

随着稠油油气资源不断勘探开发,稠油黏度升高。在热采过程中,由于热量散发大,油气温度很低,导致流动性变差,甚至出现凝固,降低了稠油产量。针对这一问题,以SiO_(2)气凝胶为原料,采用正辛烷溶剂对其进行改性制得了具有良好分散特点的纳米亲水性气凝胶HYA-1。研究表明,加入2%亲水气凝胶HYA-1,水泥石养护14 d后抗压强度衰减不明显,抗折强度提高了1.09倍,具有良好的力学性能,渗透率降低了97%,水泥石导热系数降低了91%,实现了二氧化硅气凝胶低导热的属性。HYA-1应用到旅大热采固井中,显著降低了热采固井水泥浆的导热系数,固井质量优秀,解决了渤海辽东湾海域热采井热量损失大的问题,满足了正常热采固井水泥浆的隔热和保温需求。

从含油污泥中回收油技术的研究

研究从某炼厂含油污泥中回收油的问题，分析结果表明：此种油污泥含油率46.7％、含水率51.2％、含砂率1.7％。实验中分别研究了离心法、热滤法的回收油效果。最终以热滤法实现了油回收率95％、脱水率99%。确定了以热滤法作为该含油污泥回收油的方法。

基于三碳醇溶剂精制再生废润滑油

溶剂精制再生废润滑油具有环保、经济、高效的特点,采用单因素实验方法,以三碳醇(异丙醇、正丙醇)极性溶剂为萃取剂、乙二胺为絮凝剂组合精制再生废润滑油。最佳工艺条件:萃取溶剂异丙醇、精制时间25min、精制温度40℃、剂/油质量比9、絮凝剂质量分数1.2%。在该精制工艺条件下,再生油的性能指标得到明显改善,黏温指数达130以上、闪点超过210℃、酸值为0.05mg KOH/g、灰分降至0.01%以下、重金属元素含量显著下降,再生油产率为76.8%,基本上符合HVI150基础油指标,表明该精制工艺再生废润滑油可行,具有广阔的应用前景。

TC-2复合絮凝剂处理稠油污水达标回注

针对稠油污水乳化严重 ,油水密度差小 ,分离沉降慢的特殊条件 ,通过实验筛选研制出具有强化破乳和高效絮凝作用的TC - 2复合絮凝剂 ,现场试验证实TC - 2复合絮凝剂是一种性能优良、工艺适应性好。