Advanced Materials Research Vols. 62-64

Abstract: The effect of particle sizes on the reinforcing properties of locally sourced filler (P.K.S) on rubber compound (foot mat) was investigated. This was also compared with the characteristics of kaolin filled vulcanisate. Various particle sizes of kaolin and palm kernel shell (P.K.S); 75µm, 150µm, 212µm and 300µm were used. Different physical tests relating to the required service conditions (hardness and compression set) were carried out on the vulcanisate. From the results, it was observed that P.K.S (pH of 6.25 and moisture content of 10.9%) at particle sizes 75µm and 212µm had better hardness and compression set resistance and this could be recommended for products where these properties are desired.

Abstract: The effect of two lubrication additives on the physical and chemical properties of refined soybean oil was studied. The two additives used were a complex blend of anti-oxidant; anti-wear and pour-point depressant-AP821 and AP820- used in the production of Super v and Visco 2000 brands of lubricants respectively. The physical and chemical properties of the soybean oil and base oil samples containing varying percent by volume of each additive were analysed. Results obtained show that the flashpoint of soybean oil increased from 256.6oC to 265oC and 284oC for the AP821 and AP820 additives respectively. This was better than the increase recorded for the base oil which increased from 208oC to 215 oC and 228oC for the AP821 and AP820 additives respectively. Other results obtained for pour point reduction, specific gravity and viscosity showed a positive effect of the additives on soybean oil.

Abstract: The samples in the study of Ashaka cement environs were collected on both mineralized and unmineralized ground. These were analyzed to determine the amounts of the elements absorbed by the plants in the area under study using analytical methods (IR, AAS). The observations and prediction of the results show that secondary carbonate minerals, especially those of the common base metals such as magnesium, lead and zinc may be found in Gombe-Bauchi ore bodies include associate minerals. The associate minerals that may be found are hydrozincite, Zn5(CO3)2(OH)6, hydrocerussite, Pb3 (CO3)2 (OH)2 and the very rare mineral plumbonacrite, PbOO(OH)6(CO3)2, Dypingite, Mg5(CO3)4(OH)2.5H2O etc. This is in accordance with the statistical interpretation of the results. The standard deviation were identified as action line , which is equivalent to 59.16 and 49.84 , while two standard error as warning lines, that is resulting in 58.91 . The expectation of these minerals in abundance depends on the ratio of a(Ca2+)/a(Mg2+), a(Ca2+)/a(Zn2+) and a(Ca2+)/a(Pb2+). The technological importances of these associate and very rare minerals are discussed.

Abstract: Hot flat rolling simulation by use of the Bland and Ford’s cold rolling (HRBF) theory confirmed the reverse sandwich effect in selected carbon steels at low strain rates. The Reverse Sandwich Model (RSM) was subsequently integrated into the HRBF theory for load and torque estimation. In this work, the effect of pass reduction on rolling temperature distribution, yield stresses and rolling load were studied for AISI Type 316 stainless steel (HCSS316). For this new simulation, at low and high strain rates, results showed that the ratio of experimental to calculated roll load and torque were higher at lower reduction than at higher reduction. These results confirmed excess load and torque in the hot rolling of HCSS316 at low reductions. This is in agreement with results obtained using Sim’s theory, HRBF theory and the RSM.

Abstract: This work developed several welding flux compositions and came up with an optimum composition using the bending strength test technique. The technological performance of the optimum flux compositions with respect to the bend test was 230kN/m2. Preliminary weld tests showed that the flux performed well.

Abstract: Nigeria imports large quantities of activated carbon annually for local use. In this study the development of low cost and effective adsorbent from the palm kernel shell for the treatment of waste water is examined.Palm kernel shells were used to produce activated carbon by carbonization at different temperatures (500 -10000C) and by chemical activation using 1M citric acid and saturated ammonium chloride as activated agents. The optimum temperature of carbonisation was found to be 950oC, the activated carbons produced were characterized. The measured characteristics: yield, pH, bulk density, surface area, porosity, resistance to mechanical abrasion and total surface charge of the activated carbon prepared from palm kernel shell were 18.6%, 7.8, 0.636g/ml, 112.09mgl2/gC, 19.23%, 2.36molH+/gC respectively, for citric acid activated carbon . For ammonium chloride activated carbon they were determined to be 17.50%, 8.55, 0.716g/ml, 109.69mgl2/gC, 19.76% and 2.06, 2.36molH+/gC respectively. The experimental results showed the possibility for the production of activated carbon with well developed pore structure, surface, and bulk density high mechanical abrasion and reasonable total surface charge.

Abstract: This research seeks to explain the effects of various preservative agents on starch adhesives. Adhesives were produced from cassava starch by gelatinizing with sodium hydroxide and heat. Modifications and addition of preservative agents to these adhesives were done in order to obtain a suitable working consistency and also to prolong their shelf life. Starch adhesives formed by gelatinizing with sodium hydroxide possesses good working properties, but requires mild alkalinity (pH 9.60). The stability of the final adhesives produced was also found to be dependent on the pH. At pH 9.60, the percentage decrease of viscosity after 18 days was 69.6%, while at pH 3.2, it was 98.85%. The shelf life was also controlled by adding various preservative agents to the adhesives pastes. The preservative agents added were formaldehyde, benzoate and butraldehyde. The addition of 2g of these preservative agents per 100g adhesives reduced the percentage decrease of viscosity by as much as 40% compared to that when preservative agents were not added.

Abstract: Case studies from two Nigerian hydrocarbon processing industries, where gas turbine generators (GTG) were used for power generation were analyzed. The first study analyzed a simple cycle power generation where the GTG produced 25 MW of electricity and three separately fired boilers produced the required process steam. The second study analyzed a combined cycle (cogeneration) where the same GTG that produced 25 MW of electricity also generated 90700 Kg/hr of steam from the turbine exhaust gas. The study shows that cogeneration (combined cycle) satisfied all the electric power and steam requirements of the plant. Simple cycle only satisfied the electric power requirement. Other disadvantages of simple cycle show that over 60% of the generated energy is lost to the environment in form of heat. A loss in production worth over $6,182,400 as a result of failure in a separately fired boiler was calculated. The study concludes that cogeneration must be undertaken with an awareness of energy system expansion, generation costs and the need for industrial energy consumption of a given plant.

Abstract: Dimensionless pressure derivatives of a laterally infinite reservoir drained with a horizontal well are studied. The effect of anisotropy on the derivative response is also studied. It is revealed that anisotropy mainly affects the start of the late radial flow regime, and for cases where LD is small (<0.5), affects the end of the first radial flow regime. Time criteria equations were also developed to delineate flow periods and have been shown to give good results for the range 0.00005 ≤ rwD ≤ 0.01 and 0.1 ≤ LD ≤ 100.

Abstract: Layered reservoir systems present a huge challenge to both reservoir and production engineers, because of difficulty encountered in reservoir management and well completions. In this paper, the solution to a 2D reservoir model is utilized to study pressure and pressure derivatives of a two-layered crossflow reservoir with a vertical well. No skin and wellbore effects are included. The interlayer fluid transmissibility ratio is varied for the same layers properties, to study the effects of layers heterogeneity and well completion choice on flow performance. Results show that decreasing values of specific transmissibility ratio, , signifies completion in the more permeable layer, a shift in the pressure response to the left and a short transition period to depletion of the second layer. Furthermore, increasing values  means that the well is completed in the lower permeability layer causing delay in the depletion of the second layer as a result of long transition period.