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Open access

Oleksandr Kvartenko, Larysa Sabliy, Nataliya Kovalchuk and Andriy Lysytsya

Abstract

The use of the biological method is promising for treating underground waters from iron compounds. Iron bacteria used in the process are widely spread in weak acidic and neutral underground waters containing iron ions (II), dissolved carbon dioxide and minimum concentrations of oxygen. The relevant direction of present-day biotechnology is the use of iron bacteria for treating underground waters. The goal of this research is to compare the efficiency of using the biological method for treating underground iron containing weak acidic and neutral waters under different conditions. As the test-objects, Gallionella and Lepthotrix iron bacteria were used. The sedimentation of bio-minerals was obtained from the washout waters of the biological deironing station. Calcium soda was used as an additional source of inorganic carbon for bacteria. As a result of the studies it is established that the use of the non-reagent method gives the possibility to achieve only 80% efficiency in removing iron compounds while the use of sodium carbonate results in increasing efficiency up to 93%. To determine the contribution of biological purification of ground water from iron compounds, the bacteria were inhibited with the preparation of polyhexamethylene guanidine (PHMG) chloride. It was found that inhibition of Gallionella and Lepthotrix led to the reduction of 50% of the iron removal effect. The mechanism was developed of inhibiting the process of iron bacteria metabolism by PHMG (polyhexamethylene guanidine). The new technology of arranging a block-module station for treating underground waters is proposed.

Open access

Serhii Martynov, Victor Fylypchuk, Vitalii Zoshchuk, Serhii Kunytskyi, Andrii Safonyk and Oleg Pinchuk

Abstract

Different types of filters are used to remove iron from underground water, one of them is foam polystyrene. Depending on the chemical water composition, tasks for water supply and other working conditions of iron-removing filters, it is necessary to define an exact grain size, specific granulometric composition, the thickness of the layer and the adequate rate of filtration. This kind of problems is multifactorial and its solution is based on the mathematical modelling.

As a rule, two parallel processes considered during iron removal of underground water in filters: efficiency of water treatment and growth of head losses. Therefore, the model of water iron removal based on two main blocks, clarifying block takes into account the material balance and kinetics of the process; hydrodynamic block describes the dynamics of head loss in the granular loading. The kinetics of the detention of iron compounds in granular loading consists of two mutually opposite processes. With an increase of the amount of adsorption-catalytic precipitate, the rate of sorption of iron compounds and oxidation of ferric iron increases and the efficiency of iron-removing increases. On the other hand, with decreasing porosity of loading the true velocity of the fluid increases, that reduces the intensity of adhesion of iron compounds.

Developed mathematical model allows for determining optimal values of structural and technological parameters of iron-removing filters taking into consideration the specific filtering conditions.

Open access

Caiyun Gu, Peng Zhao, Li Wang and Hongxia Guo

Abstract

To solve the problem of offshore oilfield development, based on the newly introduced pulsed neutron oxygen activation logging instrument, the application research of test design and interpretation method was carried out and applied to actual production. The structure, technical indicators and logging principles of pulsed neutron oxygen activation logging tools were introduced. The test design under different well conditions was studied, including general positive and negative injection, oil sleeve injection, single oil pipe configuration and multitubing configuration. A large amount of field test data was collected and analysed technically. A set of effective interpretation models was proposed. The corresponding interpretation software was developed. A set of test design methods and operating specifications for different well conditions were developed. Based on the conventional interpretation method, the peak selection, the double-tuber peak identification and the carbon dioxide flooding interpretation method were added. The results show that the test design and interpretation methods were applied well through a large number of field tests and production applications. Therefore, pulsed neutron oxygen activated injection profile logging technology is successfully applied in offshore oil fields.

Open access

Marek Kopacz, Agnieszka Kowalczyk, Sylwester Smoroń and Zbigniew Ostrach

Abstract

The article presents the results of the analysis of water needs in agricultural production of the Grybów commune (the district of Nowy Sącz, the Małopolska province). The aim of this study was to determine both the current water needs for agricultural purposes as well as changes in this regard based on structural and production data. The guidelines specified in the Ordinance of the Minister of Infrastructure of 14 January 2002 concerning average norms of water consumption were applied to determine water needs. The average annual water demand of crops together with permanent grassland (meadows, pastures) amounts to 23.7 mln m3, of which about 2.15 mln m3 is for winter wheat, 1.92 mln m3 for potatoes and 17.6 mln m3 for permanent grassland. Significant amounts of water (over 130,000 m3) are used also for watering home gardens and cultivating vegetables in plastic tunnels and greenhouses. Water needs for animals farming reach about 235,000 m3 in a year. Most water is needed for farming the cattle. It is predicted that the demand for water in the agricultural sector of the commune will increase by about 5.5% by 2030. Therefore, the activities monitoring the awareness of water saving and proper water management among the population of the villages are important.

Open access

Lili Dong, Gouhui Liu, Xin Ye and Wei Wang

Abstract

To realize “seamless” connection of ocean port container multimodal transport, efficiently carry out “door-to-door” transport of ocean port containers and overcome the shortcomings of existing highway and railway vehicles, this study takes the standard for heavy-duty container vehicles in TB1335-1996 Railway Vehicle Strength Design and Test Identification Code as the design basis and designs a new ocean port container transport vehicle in combination with automatic guidance technology. This study innovatively designs the automatic lifting system of the bogie and the docking part of the vehicle, introduces the automatic guidance technology and the remote-control technology to optimize the car body structure, and uses the SAP software to carry out the finite element analysis of the car body load capacity and Flexsim software to carry out the simulation analysis on the operation of vehicles. The designed transfer vehicle can improve the transfer efficiency of ocean port containers, reduce the transit time of field and station equipment and container transport links, and improve the level of multimodal transport and comprehensive economic benefits.

Open access

Jun Du, Ruo Nan Li, Xin Wu and Yan Zhang

Abstract

With the rapid development of shipbuilding industry exhaust world is also very harmful one kind of environmental issues, and the ship marine diesel engine exhaust gas is mainly produced, so in recent years it has developed a diesel engine SCR system. SCR system can control emissions of nitrogen oxides in the exhaust of vessel, furthermore air pollution can be reduced. The main goal of article was using fluent software to correct SCR system selection and flue gas flow under different size best deflector arrangement is simulated. Next goal is further optimize the structure of the SCR system.

Open access

Desen Kong, Meixu Deng, Yi Liu and Xiaoyan Tan

Abstract

To study the force and deformation characteristics of subsea mudmat-pile hybrid foundations under different combined loads, a project at a water depth of 200 m in the South China Sea was studied. A numerical model of a subsea mudmatpile hybrid foundation is developed using the numerical simulation software FLAC3D. The settlement of the seabed soil, the bending moments of the mudmat, and the displacements and bending moments along the pile shaft under different load combinations, including vertical load and horizontal load, vertical load and bending moment, and horizontal load and bending moment load, are analyzed. The results indicate that settlement of the seabed soil is reduced by the presence of piles. The settlement of the mudmat is reduced by the presence of piles. Different degrees of inclination occur along the pile shaft. The angle of inclination of pile No. 1 is greater than that of pile No. 2. The dip directions of piles No. 1 and No. 2 are identical under the vertical load and bending moment and are opposite to those under the other combined loads. The piles that are located at the junctions between the mudmat and the tops of the piles are easily destroyed.

Open access

Fu Qiang, Chen Ming, Wang Xiuli, Zhu Rongsheng, Zhang Guoyu and Yu Jianen

Abstract

The micro air nucleus widely distributed in the ocean is a necessary condition for the cavitation of hydraulic machinery in seawater. In order to study the stability of air nucleus in seawater and cavitation inception, the computational domain of water molecules with air nucleus was studied using the method of molecular dynamics simulation, and the transient characteristics of air nucleus in liquid water were obtained. The key factors influencing nuclei stability were analyzed. The results showed that air nucleus with a certain mass could maintain the dynamic equilibrium in liquid water. The internal density of air nuclei had a critical value that allowed the nuclei to stably exist in water. The air nuclei mass was the decisive factor in its equilibrium volume in water, and the two were positively correlated. The internal density of air nuclei was negatively correlated with the nuclei radius when the nuclei was stable in water. Liquid surface tension was an important factor affecting the stability of the air nuclei. The larger the initial radius of nuclei, the smaller the water pressure, and the more likely the cavitation occurs.

Open access

John W. Magugu, Song Feng, Qiuqiong Huang and Gilbert O Ototo

Abstract

Agro-forestry (AFR) technologies are perceived to improve livelihoods and natural resource sustainability of the rural households. Despite their aggressive promotion by multiple national and international agencies, the adoption of AFR technologies has been minimal in Kenya. This study conducted a survey to examine the socio-economic factors that affect the adoption process in Nyando, Kenya. Results revealed that farmers with bigger farms and higher education were more likely to adopt the new technology. Additionally, farmers were quicker to adopt technology if they had an increase in crop yields and had stayed longer in the study area. Generally, wealthier famers tended to adopt more AFR technology than those with less income. Access to information was the only factor strongly correlated with the rest of the independent variables. The results suggest that, adoption would be more enhanced with a clear focus on extension activities, income enhancing AFR practices and soil amelioration technologies. This study may be replicated in other parts of Kenya and East Africa to improve the level of AFR technology adoption for sustainable rural development.

Open access

Yanzhe Hu, Mengjie Xu and Yang Li

Abstract

In order to discuss the simulation model of the ship transmission line and the state of the transmission line, an early fault model is built according to the evolution principle of the short circuit fault of the transmission line and combining with the fault characteristics of the early fault. A small distributed ship transmission line system is built in MATLAB/ Simulink. Then, combined with the constructed fault module, the original short circuit module, and the load module, the various states (normal state, early fault state, severe early fault state, short circuit state) of the ship transmission line are stimulated, and the features of voltage signal in each state is analysed. It is concluded that, due to the normal operation of the ship transmission line system, the variation characteristics of the flow signal and voltage signal caused by the sudden load mutation, that is, the sudden load and the sudden increase load, are very similar to the changes caused by the early fault. Therefore, in order to find a more accurate early fault detection method, the state is divided into normal state, sudden load state, sudden increase and sudden decrease load state.