Advanced Materials Research Vols. 734-737

Abstract: The sidewall rock area was divided into destruction zone, damage zone and elastic zone, considering that the fracturing fluid can cause sidewall rock damage and change the stress status of sidewall rock. The stress distribution calculation models for every zone were established basing on elasticity and damage mechanics. The relationship between radial stress, circumferential stress and destruction radius, damage zone was calculated. We can conclude from the calculation results that the radial stress and circumferential stress will increase with the distance away from the axis of wellbore increasing, and radial stress is greater than circumferential stress in destruction and damage zone. However, in elastic zone the radial stress and circumferential stress will decrease with the distance away from the axis of wellbore increasing. The radial stress approaches the maximum horizontal principle stress, and the circumferential stress approaches the minimum horizontal principle stress at last.

Abstract: Aiming at the southern areas of Bohai glutenite reservoir natural capacity is low, without obvious interlayer, filter lost badly, cause conventional hydraulic facturing in short of effect on increasing production, the paper conducted the research and application of technology on Y104-6 well. According to the reservoir geological characteristics and well conditions, the paper studied on fracturing scale determination, the perforating section, and the optimization of fracturing material selection, and application. Completed the injection into well fluid amount 1491.9 m³, proppant 188 m³, displacement of pump 7.5 m³/min. After treatment, average fluid flowing production achieved 18.6 t/d, average daily oil production 6.8 t, stimulate effect and the economic benefit is remarkable. This well fracturing technology, make the successful application of the southern areas of Bohai glutenite reservoir a significant breakthrough, recoverable reserves get promoted for big thick section glutenite reservoir development and vertical fracturing of the organization and implementation has provided valuable experience.

Abstract: The gathering and transportation technology on electrical heating is one of major ways of the gathering and transportation for low permeability and low-yielding oil field, this paper has set up the physical model and mathematical model of the gathering and transportation that is controlled by time. By solving the model, we can determine the start and stop cycle of the gathering and transporting pipelines and dendriform net by electrical heating. And we also have conducted field test, the experiment turns out that the error of the result which is calculated by model compared with actual operational result is less than 1%, the phenomenon meets the requirements of production, the results can be used to determine the start and stop cycle of the gathering and transportation by electrical heating in the process of production.

Abstract: In the process of bottom argon blowing large argon flow rate can cause vigorous fluctuations on the surface of the molten steel and splash and reoxidize the molten steel, making the slag rolled into the steel slag, also causing the erosion of the ladle lining refractories. A 1:7 ratio ladle water model system of 150 ton ladle was established from the similarity theory in the lab. Study and analyze the effects of the inserting depth and diameter of immersed tube and bottom blowing flow rate on the fluctuation of the surface of liquid steel. Results show that the fluctuations on the surface of steel can be limited effectively by changing the diameter and inserted depth of immersed tube when selecting a larger flow rate of bottom blowing, which improve the mixing effect of liquid steel.

Abstract: There were two controlling factors, which should be kept balance of raw input and energy during titanium slag smelting in closed high power direct current electric arc furnace, DC furnace for short. The first factor contains compositions and ratio of input raw materials. Compositions of the raw could influence the progress and technical indicators of DC furnace smelting, and on the meanwhile, it could determine the compositions of impurity and contents of TiO₂ in titanium slag. On the other hand, the ratio of input infected the compositions of the slag, while too much anthracite would disadvantage to produce high quality slag because of impurity being reduced continually. Meanwhile much more low-state titanium would be generated. The second factor was an important one that energy equilibrium, which influence the production safety of DC furnace. It could keep balance of input and output energy, while the heatloss was 4.971 MVA. While the ratio of anthracite remained the same, the energy would effect slag viscosity and equilibrium of freeze lining directly. The energy input higher than smelting need would result in burnthrough of furnace wall and hearth, on the contrary, lower than smelting need would bring about slagging difficulties. Consequently, raw input and energy must be kept dynamic balance in order to achieve high quality titanium slag and protect freeze lining.

Abstract: According to working conditions of guizhou alumina plant, the influence of sodium sulfate impurity on the seed precipitation process was studied. The results showed that the seed decomposition rate decreased with the increasing of the sodium sulfate content, and when the additive amount of Na₂SO₄ was lower, the sodium sulfate can facilitate the agglomeration of aluminium hydroxides, when the additive amount was too high, sodium sulfate can make the granularity of the product fine finally.

Abstract: Aiming at the research and develop of high sulfur bauxite, the salt discharge experiment in sodium aluminate seeded precipitation mother liquor had been studied. The results proved that, in the evaporation process, Na₂O_k concentration should be controlled in 300-320g/l to prevent Al (OH)₃ from precipitation. The additive amount of Na₂SO₄ had a great influence on the precipitate of Na₂CO₃, Na₂SO₄ and Al (OH)₃. The precipitation rate increased with the increasing of Na₂SO₄ content. All things considered, salt discharge effect was better when N_s was 4.5~5g/l.

Abstract: The high-carbon steel was micro-alloying by Ce and Nb respectively, and the effect of micro-alloying on the nucleation of pearlite was reported in the present work. The results show that the pearlite could nucleate in rare earth sulfide inclusions and Nb-containing precipitates. The formation of NbC caused the C-depleted zone, promote the formation of proeutectoid ferrite of the pearlite. And the strain energy caused by rare earth sulfide inclusions will provide activation energies for pearlitic transformation. The inclusion and precipitates will increase the rate of nucleation of pearlite and refined the microstructures of pearlitic steel.

Abstract: As soft magnetic alloy, Si steel has been brought to the attention of the people. When the content of Si is about 6.5%, the magnetic induction intensity is highest, and the wastage of the iron is lowest, with good magnetic energy. Due to the brittleness and poor process-ability of the 6.5% Si silicon, the traditional production process is very difficult to be used for the production. With traditional production process, the content of Si in silicon steel is commonly 0.1% ~ 4.0%, which makes the property of the silicon steel limited. Use molten salt electro-position method to product silicon steel on the basis of silicon steel surface, to lay the foundation for producing 6.5% Si silicon steel. The influence of the process parameters of molten salt electro-position method to the deposit surface morphology and the silicon content distribution from surface to inside shows that along with the increase of the electro-position time, the size of sediment particle on the deposit surface gradually increases. The sedimentary thickness is proportional to the electro-deposition time.

Abstract: This paper involves the preparation of cold bonded carbon bearing pellets of metallurgical dust for direct reduction using binder. Investigation reveals that the binder is of vital concern to the preparation of cold bonded carbon bearing pellets. For agglomeration these metallurgical dust, quick lime displays excellent adhesive ability. The strength of pellets with addition 10% quick lime and mixing 9% moisture content after 2 h dried are about 700 N and over 20 times respectively, which is enough to charge the composite pellets into rotary hearth furnace or rotary kiln. In cold bonding, the (3, 3) simplex lattice method was used to find a blend of binders that would result in optimum mechanical properties. Pellets were made up by composite binders, in which quick lime content within the range from 5 to 10%, bentonite content within the range from 0 to 2% and X from 0 to 0.7% possessing the CSP and DSP higher than 300 N, 11 times respectively, from the models of the mechanical properties.