Study of different operating parameters of fcc unit with aspen-hysys

Fluid catalytic cracking unit (FCCU) is known as the heart of the modern refinery process. An FCC gives a product specific process eliminating undesired products to a larger extent. While it is mostly used to increase the production of gasoline, it also has the ability to give different products like propylene and butylene under different conditions. Crude oil contains hundreds of hydrocarbons from light gases to molecules boiling above 343 °C, most of the molecules being in the higher end. About 30 % of the feed to the distillation column cannot be separated into usable fractions in the market. FCC uses this as its feed, the atmospheric gas oil and vacuum gas oil. An FCC is used to produce low molecular weight compounds like gasoline from heavier molecules by the process of catalytic cracking. In this project, a basic refinery process was designed and the atmospheric gas oil from the distillation column was used as feed in the FCC unit.The plant data was referred from the plant data collected by Theologous et al. in which few changes were made in order to achieve proper simulation. A variation of certain parameters was also carried out to give a view of the effect of these parameters on the production of Naphtha, coke and the total conversion in the FCC unit. Two different catalysts were also used and product yield was noted. The effect of dual riser with respect to one riser was also carried under a specific range

Quantification of the energy required for the destruction of Balanus amphitrite larva by ultrasonic treatment

Ultrasonic treatment, a relatively less explored technology in water disinfection, was used to quantify the energy required for the destruction of larvae of barnacle Balanus amphitrite, which is a major marine fouling and a potential invasive organism. Since the power used and treatment time for disinfection are economically, and practically, the most important parameters, the energy required to pulverize the larvae into pieces ≤30 μm was determined as a function of the acoustic power density. The present investigation suggests that an ultrasonic system operating at 20 kHz and 0.0975 W/cm3 can effectively pulverize barnacle larvae having length (~440 μm) and breadth (~350 μm) within 45 seconds using 0.1 mJ/larva of pulverization energy. It was also observed that following pulverization of the larvae, the bacterial abundance increased and the rate of release of bacteria was dependent on power level and treatment time, which in turn decided the pulverization rate and hence the rate of release of bacteria

Larvae of fouling organisms and macrofouling at New Mangalore Port, west coast of India

Polychaetes, bryozoans, barnacles and ascidians were the dominant groups in the fouling community at New Mangalore Port. Polychaete and cirripede larvae were encountered throughout the year. Even though bivalve were present in the planktonic hauls throughout the year, their representation in the macrofouling community was not prominent and yielded a poor correlation with recruitment. Bryozoan and ascidian larvae were sparsely encountered but indicated as significant correlation with their recruitment in macrofouling community

Biokemijska karakterizacija rekombinantne ksilanaze iz bakterije Bacillus tequilensis BT21 i njezina primjena u proizvodnji ksilobioze iz poljoprivrednih otpadaka

Bacterial strain Bacillus tequilensis BT21 isolated from marine sediments was found to produce extracellular xylanase. The xynBT21 gene encoding xylanase enzyme was cloned and expressed in Escherichia coli. The gene encoded a protein consisting of 213 amino acid residues with calculated molecular mass of 23.3 kDa. Purified recombinant xylanase had optimum activity at 60 °C and pH=6. The enzyme was highly stable in alkaline pH, at pH=7 it remained 100 % active for 24 h, while its activity increased at pH=8 and 9 during incubation. B. tequilensis BT21 xylanase had alkaline pI of 9.4 and belongs to glycosyl hydrolase family 11. The mode of action of XynBT21 on beechwood xylan and xylooligosaccharides was studied. It hydrolysed xylooligosaccharides and beechwood xylan yielding mainly xylobiose (X2) with a small amount of xylose (X1), indicating that XynBT21 was probably an endo-acting xylanase. Enzymatic hydrolysis using wheat bran as a substrate revealed that xylanase reported here has the potential to produce xylobiose from wheat bran. Xylooligosaccharides, especially xylobiose, have strong bifidogenic properties and are increasingly used as a prebiotic. This is the first report that describes this novel xylanase enzyme from marine B. tequilensis BT21 used for the release of xylobiose from wheat bran.Utvrđeno je da soj bakterije Bacillus tequilensis BT21, izoliran iz morskog sedimenta, može proizvesti izvanstaničnu ksilanazu. Gen xynBT21 za kodiranje ksilanaze kloniran je i eksprimiran u bakteriji Escherichia coli, gdje je kodirao protein molekularne mase od 23,3 kDa, koji sadržava 213 aminokiselinskih ostataka. Optimalna aktivnost pročišćene rekombinantne ksilanaze postignuta je pri temperaturi od 60 °C i pH=6. Enzim je bio izuzetno stabilan pri alkalnim pH vrijednostima. Pri pH=7 aktivnost mu je bila 100 % tijekom 24 sata, dok se tijekom inkubacije pri pH=8 i 9 aktivnost enzima povećala. Ksilanaza iz B. tequilensis imala je alkalnu pI vrijednost od 9,4; a pripada obitelji glikozilnih hidrolaza 11. Ispitano je djelovanje ksilanaze XynBT21 na ksilan iz bukve i ksilooligosaharide. Njihovom hidrolizom dobivena je pretežno ksilobioza (X2) uz manju količinu ksiloze (X1), zbog čega je zaključeno da je XynBT21 vjerojatno endoksilanaza. Enzimskom hidrolizom pšeničnih mekinja potvrđeno je da ksilanaza može proizvesti ksilobiozu na toj podlozi. Ksilooligosaharidi, osobito ksilobioza, imaju snažna bifidogena svojstva, pa se sve češće primjenjuju kao prebiotici. Ovo je prvi rad koji opisuje primjenu nove ksilanaze iz morske bakterije B. tequilensis BT21 za oslobađanje ksilobioze iz pšeničnih mekinja

Effect of hydrodynamic cavitation on zooplankton: a tool for disinfection

Application of hydrodynamic cavitation for disinfection of water is gaining momentum, as it provides environmentally and economically sound options. In this effort, the effect of cavitating conditions created by differential pump valve opening and that created by flowing through a cavitating element (orifice plates) on the microbes (zooplankton in sea water) is described. The experimental results are compared with modelling of cavitating conditions that includes cavity dynamics, turbulence generated by individual oscillating cavity, cell wall strength and geometrical and operating parameters of cavitation device. Theoretical model for quantifying the cavitationally generated turbulent shear and extent of microbial disinfection has been developed. Experimental results indicated that cavitation and/or turbulent fluid shear dominantly originating from cavitation are effective tools for sea water disinfection as more than 80% of the zooplankton present in the sea water were killed. It was also observed that shock waves generated due to cavitation is not the sole cause for zooplankton disruption. A correct physical mechanism accounting fluid turbulence and shear, generated from stable oscillation of cavity, significantly contribute towards the disruption. Further refinement of the model presented will serve as a basis for higher degree of disinfection and provide a practical tool for sea water disinfection

Phytoplankton and Bacterial Communities in South Harbour, Manila Bay, Philippines

In line with the ASEAN-India project “Extent of Transfer of Alien Invasive Organisms in South/Southeast Asia via Shipping”, phytoplankton and bacterial communities in the waters off South Harbour, Manila Bay were investigated. Sampling was done in July and August 2012 and in April and May 2013. A total of 67 phytoplankton species including 29 diatoms and 38 dinoflagellates were identified. Potentially toxic Pseudo-nitzschia spp. were among the diatoms found as well as dinoflagellates Alexandrium spp., and Gymnodinium spp. The diatom Skeletonema costatum appeared to be the dominant species in July and August 2012, whereas Chaetoceros spp. constituted over 85% of the total phytoplankton assemblage in April and May 2013. Mean bacterial abundance ranged from 9.53 x 102–3.18 x 105 cells/mL in July 2012. In addition, 93 bacterial isolates were  identified using 16S rDNA, several of which belonged to the following phyla: Actinobacteria, Bacteriodetes,  Firmicutes, and Proteobacteria; whereas, others were determined as uncultured bacterial clones. These results will serve as a valuable baseline for future studies on phytoplankton and bacterial community structure in Manila Bay

Structural characterisation of the N-glycan moiety of the barnacle settlement-inducing protein complex (SIPC)

Many barnacle species are gregarious and their cypris larvae display a remarkable ability to explore surfaces before committing to permanent attachment. The chemical cue to gregarious settlement behaviour – the settlement-inducing protein complex (SIPC) – is an α2-macroglobulin-like glycoprotein. This cuticular protein may also be involved in cyprid reversible adhesion if its presence is confirmed in footprints of adhesive deposited during exploratory behaviour, which increase the attractiveness of surfaces and signal other cyprids to settle. The full-length open-reading frame of the SIPC gene encodes a protein of 1547 amino acids with seven potential N-glycosylation sites. In this study on Balanus amphitrite, glycan profiling of the SIPC via hydrophilic interaction liquid chromatography with fluorescence detection (HILIC-fluorescence) provided evidence of predominantly high mannose glycans (M2–9), with the occurrence of monofucosylated oligomannose glycans (F(6)M2–4) in lower proportions. The high mannose glycosylation found supports previous observations of an interaction with mannose-binding lectins and exogenous mannose increasing settlement in B. amphitrite cypris larvae. Transmission electron microscopy of the deglycosylated SIPC revealed a multi-lobed globular protein with a diameter of ∼8 nm. Obtaining a complete structural characterisation of the SIPC remains a goal that has the potential to inspire solutions to the age-old problem of barnacle fouling.No Full Tex

Recruitment in the sea: bacterial genes required for inducing larval settlement in a polychaete worm

Metamorphically competent larvae of the marine tubeworm Hydroides elegans can be induced to metamorphose by biofilms of the bacterium Pseudoalteromonas luteoviolacea strain HI1. Mutational analysis was used to identify four genes that are necessary for metamorphic induction and encode functions that may be related to cell adhesion and bacterial secretion systems. No major differences in biofilm characteristics, such as biofilm cell density, thickness, biomass and EPS biomass, were seen between biofilms composed of P. luteoviolacea (HI1) and mutants lacking one of the four genes. The analysis indicates that factors other than those relating to physical characteristics of biofilms are critical to the inductive capacity of P. luteoviolacea (HI1), and that essential inductive molecular components are missing in the non-inductive deletion-mutant strains

Understanding our seas: National Institute of Oceanography, Goa

The present article summarizes the research done at the CSIR–National Institute of Oceanography in 2014 in ocean science, resources and technology. Significant research has been conducted on air–sea interactions and coastal circulation, biogeochemistry, biology, marine geophysics, palaeoceanography, marine fishery, gas hydrates and wave energy. Technological advances covered topics like oceanographic tools. Major strides have been made in marine resources research and evaluation