scholarly journals OPTIMIZING PRE LIMING PH FOR EFFICIENT JUICE CLARIFICATION PROCESS IN SRI LANKAN SUGAR FACTORIES

Author(s):  
M.G.G Natasha Sewwandi ◽  
Sandya Ariyawansha ◽  
Buddhika Sampath Kumara ◽  
Aloka Maralanda

- This study was conducted treating with Milk of Lime to reach different pH levels (T1- with Initial pH, T2, T3 and T4 with 6.5, 7.5 and 8.5 of pH respectively) to determine the optimum pre-liming pH which could result in best cane juice clarification in Sri Lankan sugar industries. The experiment design used was RCBD with five replicates. ANOVA followed by Duncan’s Multiple Range Test (DNMRT) were used to identify significant mean differences. Regression analyses were carried out to model the variation of turbidity, mud volume and CaO with change of juice pH. Quadratic model (R2 = 99.2 %, p <0.001) best fitted to explain the effect of pH on turbidity of juice. Effect of pH on deposited mud volume and CaO were explained by cubic models with R2 = 99.4 % (p <0.001) and R2 = 93.9 %, (p <0.001) respectively. Among tested treatments, pH 7.5 is selected as the best for turbidity improvement of the clarified juice while pH 8.5 is the second best. However pH 8.5 (370 ml) was able to deposited significantly high mud volume than pH 7.5 (270 ml). Further, the amount of residual Ca2+ ions in the clarified juice at pH 7.5 (2715 ppm) is clearly lower than the amount of Ca2+ ions remaining in the clarified juice at pH 8.5 (2945 ppm). It is expected to obtain high turbidity and higher mud volume with low sugar inversion at optimum pH. Therefore the results suggest optimum pH range lie around pH 7.5 to 8.5. Conducting similar experiment by using mixed juice extracted from sugar factory mills with pH range around 7.0 to 8.4 at 0.2 increments is suggested to validate the optimum pH.

2021 ◽  
Author(s):  
Natasha Sewwandi ◽  
Sandya Ariyawansha ◽  
Buddhika Sampath Kumara ◽  
Aloka Maralanda

Abstract This study was conducted treating with Milk of Lime to reach different pH levels (T1- with Initial pH, T2, T3 and T4 with 6.5, 7.5 and 8.5 of pH respectively) to determine the optimum pre-liming pH which could result in best cane juice clarification in Sri Lankan sugar industries. The experiment design used was RCBD with five replicates. ANOVA followed by Duncan’s Multiple Range Test (DNMRT) were used to identify significant mean differences. Regression analyses were carried out to model the variation of turbidity, mud volume and CaO with change of juice pH. Quadratic model (R 2 = 99.2%, p <0.001) best fitted to explain the effect of pH on turbidity of juice. Effect of pH on deposited mud volume and CaO were explained by cubic models with R 2 = 99.4% (p <0.001) and R 2 = 93.9%, (p <0.001) respectively.Among tested treatments, pH 7.5 is selected as the best for turbidity improvement of the clarified juice while pH 8.5 is the second best. However pH 8.5 (370 ml) was able to deposited significantly high mud volume than pH 7.5 (270 ml). Further, the amount of residual Ca2+ ions in the clarified juice at pH 7.5 (2715 ppm) is clearly lower than the amount of Ca2+ ions remaining in the clarified juice at pH 8.5 (2945 ppm). It is expected to obtain high turbidity and higher mud volume with low sugar inversion at optimum pH. Therefore the results suggest optimum pH range lie around pH 7.5 to 8.5. Conducting similar experiment by using mixed juice extracted from sugar factory mills with pH range around 7.0 to 8.4 at 0.2 increments is suggested to validate the optimum pH.


2014 ◽  
Vol 508 ◽  
pp. 279-285
Author(s):  
Qi Li ◽  
Li Ya Xi ◽  
Yi Yang Feng ◽  
Lin Guo Zhao ◽  
Fei Li

The optimization of xylanase expression by recombinant Pichia pastoris were carried out in this study. Several factors were evaluated and the conclusion were as follow: the optimal conditions were in shake flask cultivation with the rotate speed 180 r/min using BMGY medium with initial pH 7.0, initial OD600 1.0, 0.1% histidine, 0.05% tween80. 1.0% methanol was added into the culture every 24 h. The xylanase activity was up to 1527 U/mL at the optimal conditions after 15 days. The optimum pH and temperature were pH5.0 and 50°C. The recombinant xylanase was stable over a pH range of 2.0-8.0. The optimal conditions of degradation were as below: after 20 h, with the pH 5.0 and temperature 45°C, 2.0% of substrate concentration, 100 U/mL of enzyme dosage and 0.05% of tween80 concentration,the degradation of xylan was the best, which indicating great potential in the bioconversion of lignocellulosic waste to xylooligosaccharide.


1997 ◽  
Vol 35 (7) ◽  
pp. 71-78 ◽  
Author(s):  
Shuzo Tokunaga ◽  
Syed A. Wasay ◽  
Sang-Won Park

A new adsorption process for the removal of As(V) ion from aqueous solutions has been studied using lanthanum hydroxide (LH), lanthanum carbonate (LC) and basic lanthanum carbonate (BLC). These La compounds were effective in removing As ion to decrease the concentration down to &lt; 0.001 mM. Dissolution of these La compounds was measured in the pH range of 2 to 12. The dissolution was appreciable at initial pH &lt;4.3, &lt;4.3 and &lt;4.0 for LH, LC and BLC, respectively. Kinetic study showed that the As removal was a first-order reaction in the neutral pH range and the rate constants were in the order of LH &gt; LC &gt; BLC. The As removal was highly pH-dependent. The optimum pH range was 3-8, 4-7 and 2-4 for LH, LC and BLC, respectively. The following two mechanisms are proposed: (i) adsorption by exchange of CO3 and/or OH group with As ions in the neutral to alkaline pH range where La does not dissolve and (ii) precipitation of insoluble lanthanum arsenate, LaAsO4, in the acid pH range.


1970 ◽  
Vol 4 (1) ◽  
pp. 26-31
Author(s):  
AB Bello ◽  
MS Sule ◽  
AJ Alhassan

The effect of pH on the activity and stability of crude polyphenol oxidase (PPO) extracted from garden egg (Solanum aethiopicum), pawpaw (Carica papaya), pumpkin (Cucurbita pepo), guava (Psidium guajava) and bush mango (Irvingia gabonnensis) fruits were studied. Catechol at concentration of 20 mM was used as a substrate while sodium acetate buffer (0.2 M), pH range between 3.0– 5.5 and sodium phosphate buffer(0.2 M) , pH range between 6.0– 8.5 were used to determine the effect of pH on the PPO activity. Optimum pH values were found to be 6.0,6.5,6.0, 4.5 and 4.0/or 8.0 for the enzyme extracted from Solanum aethiopicum, Carica papaya, Cucurbita pepo, Psidium guajava and Irvingia gabonnensis respectively. The enzyme was found to be stable at the pH range of 5.0-7.5 for the enzyme extracted from garden egg, 6.0-8.0 for that from pawpaw, 4.5-7.0 for that from pumpkin, 4.0-6.5 for that from guava and 3.5-5.5 and 7.0-8.0 for that from bush mango respectively. Increase or decrease of pH from the ranges would cause decrease in the activity of the enzyme, and can be a good way of controlling undesirable changes caused by it in foods. Keywords: Optimum pH, pH stability, Polyphenol oxidase, Common fruits.


2017 ◽  
Vol 1 (1) ◽  
Author(s):  
Rudi Nugroho

A biological denitrification using autotrophic bacteria in batch suspension runs was investigated to clarify the effect of pH on denitrification rate. Elemental sulfur was employed as an electron donor. The culture of autotrophic bacteria was obtained from activated sludge by acclimatization. The effect of pH on denitrification rate could be expressed by bell-shape equation with optimum pH of 7,07. However at a pH range of 5,5 to 8,0, the denitrification rate significantly fastl. Therefore, the application of the denitrification of wastewater using autotrophic bacteria is suggested running well although without controlling pH.  Kata kunci : Denitrification, nitrate, autotrophic bacteria, elemental sulfur, pH.


2010 ◽  
Vol 33 ◽  
pp. 700-703
Author(s):  
Hong Qin Xue ◽  
Xiao Dong Liu ◽  
Zhao Qian Jing ◽  
Chen Zhao

Adsorption of Pb(II) on composite filter material mainly made of fly ash was investigated for the removal of Pb(II) from aqueous solution. Batch experiments have been carried out for adsorption of Pb(II) on to this composite filter material. The effects of various parameters influencing the Pb(II) adsorption such as contact time, initial pH, different dosage of adsorbent and temperature have been studied. Results showed that adsorption equilibrium attained within 60 minutes time. Increase in adsorbent dosage led to increase in Pb(II) adsorption due to increased number of adsorption sites. Adsorption process was found to be highly pH dependent, and the optimum pH range for adsorption of Pb(II) was found to be >8.5. The sorption of Pb(II) increased with rise of temperature.


Water ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2031
Author(s):  
Ruben Miranda ◽  
Isabel Latour ◽  
Angeles Blanco

Effluent reuse is a common practice for sustainable industrial water use. Salt removal is usually carried out by a combination of membrane processes with a final reverse osmosis (RO). However, the presence of silica limits the RO efficiency due to its high scaling potential and the difficulty of cleaning the fouled membranes. Silica adsorption has many advantages compared to coagulation and precipitation at high pHs: pH adjustment is not necessary, the conductivity of treated waters is not increased, and there is no sludge generation. Therefore, this study investigates the feasibility of using pseudoboehmite and its calcination product (γ-Al2O3) for silica adsorption from a paper mill effluent. The effect of sorbent dosage, pH, and temperature, including both equilibrium and kinetics studies, were studied. γ-Al2O3 was clearly more efficient than pseudoboehmite, with optimal dosages around 2.5–5 g/L vs. 7.5–15 g/L. The optimum pH is around 8.5–10, which fits well with the initial pH of the effluent. The kinetics of silica adsorption is fast, especially at high dosages and temperatures: 80–90% of the removable silica is removed in 1 h. At these conditions, silica removal is around 75–85% (<50 mg/L SiO2 in the treated water).


2007 ◽  
Vol 57 (4) ◽  
pp. 730-737 ◽  
Author(s):  
Abdul Majid Maszenan ◽  
He Long Jiang ◽  
Joo-Hwa Tay ◽  
Peter Schumann ◽  
Reiner M. Kroppenstedt ◽  
...  

A Gram-positive bacterium, designated strain PG-02T, was isolated by serial dilution from aerobic granules obtained from a laboratory-scale sequencing batch reactor for bioremediation of phenolic wastewater. Strain PG-02T grew axenically as cocci and is an oxidase-negative and catalase-positive, non-motile facultative anaerobe. It does not reduce nitrate and grows between 15 and 37 °C, with an optimum temperature of 30 °C. The pH range for growth is between 5.0 and 8.5, with an optimum pH of 7.0. Strain PG-02T contains type A3γ peptidoglycan (ll-A2pm←Gly with alanine at position 1 of the peptide subunit). The G+C content of the DNA is 69 mol%. Menaquinone MK-9(H4) was the major isoprenoid quinone. The polar lipids included diphosphatidylglycerol and phosphatidylglycerol, while 13-methyltetradecanoic acid (i-C15 : 0) and 1,1-dimethoxy-iso-pentadecane (i-C15 : 0 DMA) were the major components in whole-cell methanolysates. PG-02T stained positively for intracellular polyphosphate granules but not poly-β-hydroxyalkanoates. It produces capsular material and possesses an autoaggregation capability. Phenotypic and 16S rRNA gene sequence analyses showed that PG-02T differed from its closest phylogenetic relatives, namely members of the suborder Propionibacterineae, which includes the genera Tessaracoccus, Microlunatus, Luteococcus, Micropruina, Propionibacterium, Propioniferax, Nocardioides, Friedmanniella and Aeromicrobium, and that it should be placed in a new genus and species as Granulicoccus phenolivorans gen. nov., sp. nov. The type strain of Granulicoccus phenolivorans is PG-02T (=ATCC BAA-1292T=DSM 17626T).


2017 ◽  
Vol 17 (3) ◽  
Author(s):  
Paula Zaghetto de Almeida ◽  
Marita Gimenez Pereira ◽  
Caio Cesar de Carvalho ◽  
Paulo Ricardo Heinen ◽  
Luciana Sobrani Ziotti ◽  
...  

Abstract Filamentous fungi are widely diverse and ubiquitous organisms. Such biodiversity is barely known, making room for a great potential still to be discovered, especially in tropical environments - which are favorable to growth and species variety. Filamentous fungi are extensively applied to the production of industrial enzymes, such as the amylases. This class of enzymes acts in the hydrolysis of starch to glucose or maltooligosaccharides. In this work twenty-five filamentous fungi were isolated from samples of decomposing material collected in the Brazilian Atlantic Forest. The two best amylase producers were identified as Aspergillus brasiliensis and Rhizopus oryzae. Both are mesophilic, they grow well in organic nitrogen-rich media produce great amounts of glucoamylases. The enzymes of A. brasiliensis and R. oryzae are different, possibly because of their phylogenetical distance. The best amylase production of A. brasiliensis occurred during 120 hours with initial pH of 7.5; it had a better activity in the pH range of 3.5-5.0 and at 60-75°C. Both fungal glucoamylase had wide pH stability (3-8) and were activated by Mn2+. R. oryzae best production occurred in 96 hours and at pH 6.5. Its amylases had a greater activity in the pH range of 4.0-5.5 and temperature at 50-65ºC. The most significant difference between the enzymes produced by both fungi is the resistance to thermal denaturation: A. brasiliensis glucoamylase had a T50 of 60 minutes at 70ºC. The R. oryzae glucoamylase only had a residual activity when incubated at 50°C with a 12 min T50.


2005 ◽  
Vol 71 (7) ◽  
pp. 3709-3715 ◽  
Author(s):  
Meike Ballschmiter ◽  
Martin Armbrecht ◽  
Krasimira Ivanova ◽  
Garabed Antranikian ◽  
Wolfgang Liebl

ABSTRACT Two α-amylase genes from the thermophilic alkaliphile Anaerobranca gottschalkii were cloned, and the corresponding enzymes, AmyA and AmyB, were investigated after purification of the recombinant proteins. Based on their amino acid sequences, AmyA is proposed to be a lipoprotein with extracellular localization and thus is exposed to the alkaline milieu, while AmyB apparently represents a cytoplasmic enzyme. The amino acid sequences of both enzymes bear high similarity to those of GHF13 proteins. The different cellular localizations of AmyA and AmyB are reflected in their physicochemical properties. The alkaline pH optimum (pH 8), as well as the broad pH range, of AmyA activity (more than 50% activity between pH 6 and pH 9.5) mirrors the conditions that are encountered by an extracellular enzyme exposed to the medium of A. gottschalkii, which grows between pH 6 and pH 10.5. AmyB, on the other hand, has a narrow pH range with a slightly acidic pH optimum at 6 to 6.5, which is presumably close to the pH in the cytoplasm. Also, the intracellular AmyB is less tolerant of high temperatures than the extracellular AmyA. While AmyA has a half-life of 48 h at 70°C, AmyB has a half-life of only about 10 min at that temperature, perhaps due to the lack of stabilizing constituents of the cytoplasm. AmyA and AmyB were very similar with respect to their substrate specificity profiles, clearly preferring amylose over amylopectin, pullulan, and glycogen. Both enzymes also hydrolyzed α-, β-, and γ-cyclodextrin. Very interestingly, AmyA, but not AmyB, displayed high transglycosylation activity on maltooligosaccharides and also had significant β-cyclodextrin glycosyltransferase (CGTase) activity. CGTase activity has not been reported for typical α-amylases before. The mechanism of cyclodextrin formation by AmyA is unknown.


Sign in / Sign up

Export Citation Format

Share Document