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This paper presents the findings on thermal expansion behavior of slaked lime doped rice husk silica (RHS) refractory monitored between 25 ℃ and 1500 ℃. It also reports the phase transition analysis within the temperature range of 850-1450 ℃. A sudden expansion of 0.7% noticed at 220 ℃ is due to the transformation of α-cristobalite to β-cristobalite. The highest expansion (0.85%) reached within the temperature range of 650-850 ℃, remains almost constant for the investigated temperature range, and is not high enough to cause macro cracks in the refractory. The phase transition order is similar to those reported for quartzite refractory after 600 ℃, though the crystallization temperature is lowered due to the presence of the dopant. Modulus of rupture, apparent porosity, bulk density, refractoriness and reheat change are reported and their results meet with the standards qualifying them for use in coke ovens.

There are many plant extracts that have been studied for possible use as corrosion inhibitors in the oil and gas industries. Hence, this work is focused on optimization of blended Guava and Fluted Pumpkin Leaves extract as corrosion inhibitor of mild steel in HCI using Weight loss method. Response Surface Methodology of Design Expert trial version 12 StatEase was used to design and analyze the result of the 35-run experiments. Three factor-three level was adopted in the design. Time, Temperature and Inhibitor Quantity were the independent variables, while the acid concentration of 0.5M was constant throughout the experiments and Inhibition Efficiencies were measured using IE formula. Intervals of 1 hr, 0.2g, and 10°C were chosen for the immersion time, inhibitor quantity and temperature, respectively. Phytochemical analysis carried out on the Guava and Fluted Pumpkin Leaves shows that each leaf extract contains phytochemicals which are responsible for inhibiting corrosion. Weight loss result shows that the Blended extract reduces the corrosion rate of mild steel in 0.5M HCl. Additionally, 4 experiments for Blended Extract, Fluted Pumpkin, Guava Extract and Industrial Inhibitor were carried out at optimal conditions as predicted by the software at time 4.036 hr, temperature 49.5°C, inhibitor quantity 0.487g and ratio of 59.21GE:FP40.79 Inhibition Efficiencies of the Blended, Fluted Pumpkin, Guava Extracts and Industrial Inhibitor were 93.70%, 78.14%, 63.7% and 95.18%, respectively. The results show that the blended and Industrial Inhibitor compared well with the software predicted IE of 96.085%. Therefore, the blended extract could serve as good substitute to the industrial inhibitor.

Small manufacturing plants usually experience challenges of inefficiency and low production yields. These problems have previously been addressed using methods to redesign plant layouts and reduce distance between workstations. Furthermore, assessment techniques like the machine-distance matrix method have then been required to evaluate layout performance. However, these assessments that rely only on distance evaluation are severely limited. In this paper, a new model called Production-time evaluation is presented for evaluating production layout efficiency. It involves computing the estimated time for production at workstations, time for movement between workstations and number of units of a product manufactured. It is then applied on a case study in small furniture plant. The existing layout of the plant was extracted and the production processes for its three products were outlined. A new layout was designed and both layouts were compared using the Production-time methodology, revealing improvements in reduced production time and increased daily production capacity by up to 37% for a product.