NOPR Collection:

pH Control of industrial effluent using CDM based PI controllers

2015-05-01T00:00:00Z

Title: pH Control of industrial effluent using CDM based PI controllers Authors: Meenakshipriya, B; Saravanan, K; Krishnamurthy, K; Kanthabhabha, P Abstract: Coefficient Diagram Method (CDM) based PI controllers (CDM-PI and CDM-PI-P) has been implemented in a pH neutralization system to control the pH value of industrial effluent. The proposed techniques are tested with collected effluent in lab-scale pH neutralization system. Experimental runs are carried out at the operating point of pH 8 as per the requirement of PCETP and the regulatory performance in terms of Error Indices (ISE and IAE) and Total variations (TV) are reported. The results of the proposed control techniques are compared with conventional control techniques such as Ziegler Nichols PI controller (ZN-PI) and Internal Model Control based PI controller (IMC-PI). The experimental results show that the proposed CDM based PI controllers had impeccable performance with industrial effluent in pH neutralization system. Page(s): 141-147

PSO-Fuzzy eliminates deficiency of neuro-fuzzy in assessment of asphaltene stability

2015-05-01T00:00:00Z

Title: PSO-Fuzzy eliminates deficiency of neuro-fuzzy in assessment of asphaltene stability Authors: Zargar, Ghassem; Gholami, Amin; Asoodeh, Mojtaba; Bagheripour, Parisa; Vaezzade-Asadi, Mohsen Abstract: Precipitation and deposition of asphaltene during petroleum production is a challenging problem confronted by the oil industry compromising the profitability of production fields through loss efficiency of recovery process as well as create remedial cost. Hence, developing a robust model for assessment of asphaltene stability in crude oil is necessary. ΔRI (ΔRI = RI - PRI) is a novel criterion for stability determination of asphaltene in crudes. An integrated intelligent method, called neuro-fuzzy (NF) has been used in this study for estimation of ΔRI from SARA fraction data. NF develops a fuzzy inference system which is subsequently optimized by virtue of learning capability of neural network (NN). Since NN structure, embedded in NF systems is highly at risk of sticking in local minima, another improved fuzzy model is constructed and is subsequently optimized by virtue of particle swarm optimization (PSO) technique. Correlation coefficients for neuro-fuzzy and PSO-fuzzy model are found to be 0.857 and 0.9102, respectively. Comparison between constructed models show optimization of fuzzy model by virtue of PSO technique significantly improves accuracy of final prediction. Implementation of the proposed method indicate that PSO-fuzzy model is capable of accurately predicting asphaltene stability. Page(s): 135-140

Equilibrium and kinetic studies on Ni(II) removal from aqueous solution by Citrus Limettioides peel and its carbon adsorbent

2015-05-01T00:00:00Z

Title: Equilibrium and kinetic studies on Ni(II) removal from aqueous solution by Citrus Limettioides peel and its carbon adsorbent Authors: Sudha, R; Srinivasan, K Abstract: Activated carbon has been prepared from Citrus limettioides peel (CLPC); a novel waste material by chemical modification with sulphuric acid followed by bicarbonate treatment applied for the adsorption of Ni(II) from aqueous solutions. Batch experiments have been carried out to study the effect of various parameters such as contact time, pH and adsorbent dosage on various Ni(II) concentrations along with, raw Citrus limettioides peel (CLP). The optimum pH required for the maximum adsorption of Ni(II) is found to be 4.0-9.0 and 5.0-8.0 for CLPC and CLP, respectively. The optimum contact time is found to be 4 hr in all cases of carbon and raw peel. The presence of hydroxyl and carboxylic acid groups are confirmed by FT-IR spectra. Equilibrium data agreed well with Langmuir model. Based on Langmuir isotherm the adsorption capacity is found to be 38.46 mg g^-1 for CLPC and 25.64 mg g^-1 for CLP at 300K. The kinetic data follow pseudo-second order model with film diffusion process. Similar studies have also been carried out using commercial available activated carbon (CAC) for evaluation purposes. The adsorption capacity of CAC is found to be 11.36 mg g^-1. Hence the adsorption capacity (Q_o) of CLPC and CLP is found to be 3.4 and 2.3 times greater than that of CAC. These adsorbents are also tested for the removal of Ni(II) from electroplating wastewater and found to remove 85% and 99% for CLP and CLPC respectively whereas the CAC show 75% removal only with an initial concentration of 220 mg/100 mL. The overall results indicate that carbon derived from Citrus limettioides peel (CLPC) could effectively be used to remove 99% of Ni(II) from water and wastewater. Page(s): 126-134

In vitro release characteristics of 5-fluorouracil from Aloe vera gel /guar gum blend as a carrier matrix

2015-05-01T00:00:00Z

Title: In vitro release characteristics of 5-fluorouracil from Aloe vera gel /guar gum blend as a carrier matrix Authors: Subramanian, K; Vijayakumar, V Abstract: Aloe vera gel (AVG) which is increasingly used as an excipient in sustained release pharmaceutical dosage forms due to its health benefits is sporadically studied as a drug carrier for controlled delivery. Guar-gum (GG) used for colon specific delivery is not a desirable matrix for the sustained release of 5-Fluorouracil (5-FU) in stomach and small intestine (SI) for treatment of stomach cancer as only 2% of 5-FU is released. Hence AVG is investigated as a co-carrier with GG to facilitate a sustained release of 5-FU in stomach in the present study. GG is solution blended with AVG in different proportions to achieve sustained release of 5-FU, in simulated biofluids. FT-IR, TG and DSC studies reveal only a mild physical interaction of the drug with the matrix through weak hydrogen bonding and there is no drug-matrix chemical interaction. The temperature of major weight loss degradation decrease both on the addition of drug and AVG. The in vitro release characteristics of the drug imply that addition of AVG to GG facilitate sustained release of 5-FU in stomach and SI due to enhanced matrix swellability. Blend composition and pH of the fluid control the release kinetics and the mechanism of release is found to be non-Fickian. The study demonstrates that AVG/GG blend of appropriate composition may serve as a promising matrix for the sustained release of 5-FU in stomach and SI which is difficult with pristine GG and AVG. Page(s): 120-125