• Environmental Engineering Research
• /
• v.16 no.4
• /
• pp.205-212
• /
• 2011

Reverse osmosis (RO) technology has developed over the past 40 years to control a 44% market share in the world desalting production capacity and an 80% share in the total number of desalination plants installed worldwide. The application of conventional and low-pressure membrane pretreatment processes to seawater RO (SWRO) desalination has undergone accelerated development over the past decade. Reliable pretreatment techniques are required for the successful operation of SWRO processes, since a major issue is membrane fouling associated with particulate matter/colloids, organic/inorganic compounds, and biological growth. While conventional pretreatment processes such as coagulation and granular media filtration have been widely used for SWRO, there has been an increased tendency toward the use of ultrafiltration/microfiltration (UF/MF) instead of conventional treatment techniques. The literature shows that both the conventional and the UF/MF membrane pretreatment processes have different advantages and disadvantages. This review suggests that, depending on the feed water quality conditions, the suitable integration of multiple pretreatment processes may be considered valid since this would utilize the benefits of each separate pretreatment.

• Asian-Australasian Journal of Animal Sciences
• /
• v.28 no.3
• /
• pp.369-373
• /
• 2015

An experiment was conducted to determine the effect of cellulose concentration in diets containing no phosphorus (P) on the basal endogenous loss (BEL) of P in growing pigs. Twelve barrows (an initial mean body weight = $49.6{\pm}3.2kg$) were individually housed in metabolism crates. Pigs were allotted to 4 experimental diets according to a cross-over design with 12 animals and 2 periods. Four P-free diets were mainly based on corn starch, sucrose, and gelatin, and were formulated to contain 0%, 4%, 8%, or 12% cellulose. Each period consisted of a 5-d adaptation and a 5-d collection period. The marker-to-marker method was used for fecal collection. The feed intake (p<0.05, linear and quadratic) and dry feces output (p<0.01, linear and quadratic) were increased with increasing dietary cellulose concentration. However, P concentration in the feces was decreased (p<0.01, linear and quadratic) with increasing dietary cellulose concentration. There was no significant difference in total P output and the BEL of P as mg per kg DMI (ranging from 157 to 214 mg/kg of dry matter intake) among experimental diets. However, values for the apparent total tract digestibility of energy, dry matter, organic matter, crude protein, and calcium were linearly decreased (p<0.01) with increasing cellulose concentration in the diet. In conclusion, dietary cellulose affected the amount of feces and digestibility of energy and nutrients, but did not affect the endogenous loss of P.

• Journal of Korean Society of Water and Wastewater
• /
• v.25 no.3
• /
• pp.343-348
• /
• 2011

Since 2005, food waste has been separately collected and recycled to animal feed or aerobic compost in South Korea. However, the conventional recycling methods discharge process wastewater, which contain pollutant equivalent to more than 50% of food waste. Therefore, anaerobic digestion is considered as an alternative recycling method of food waste to reduce pollutant and recover renewable energy. Recent studies showed that hydrogen can be produced at acidogenic stage in two-stage anaerobic digestion. In this study, the authors investigated the effects of pretreatment time and pH low set value on continuous mesophilic hydrogen fermentation of food waste. Food waste was successfully converted to $H_2$ when heat-treated at $70^{\circ}C$ for 60 min, which was milder than previous studies using pH 12 for 1 day or $90^{\circ}C$. Organic acid production dropped operational pH below 5.0 and caused a metabolic shift from $H_2/butyrate$ fermentation to lactate fermentation. Therefore, alkaline addition for operational pH at or over 5.0 was necessary. At pH 5.3, the result showed that the maximum hydrogen productivity and yield of 1.32 $m^3/m^3$.d and 0.71 mol/mol $carbohydrate_{added}$. Hydrogen production from food waste would be an effective technology for resource recovery as well as waste treatment.

• Asian-Australasian Journal of Animal Sciences
• /
• v.14 no.4
• /
• pp.474-478
• /
• 2001

Eighteen Murrah male buffalo calves were allotted into three groups of six each. The calves in group I (control) were fed with whole milk, skim milk, calf starter and green maize fodder. The calves in group II (high butyric acid) and group III (low butyric acid) were fed with the same diet as control along with 24 ml and 12 ml of butyric acid/calf/day for 120 days, respectively for 120 days. Dry matter intake was higher in group II and III as compared with group I. Digestibility of dry matter, organic matter, crude protein, crude fibre, ether extract, neutral detergent fibre, acid detergent fibre, cellulose and hemicellulose was the highest in group II followed by group III and the control group. Body weight gain and conversion efficiency of dry matter, digestible crude protein and total digestible nutrients were better in group II. Cost of feed for per unit of live weight gain was the lowest in group II. It was concluded that dietary addition of butyric acid (24 ml/day) was economical and had positive effect on the performance of Murrah buffalo calves.

• Asian-Australasian Journal of Animal Sciences
• /
• v.17 no.5
• /
• pp.659-662
• /
• 2004

A growth trial of 60 days with 16 male buffalo calves (10 to 11 months age; 100${\pm}$7 kg live weight mean) was conducted to investigate comparative efficacy of cottonseed meal (CSM) and sunflower meal (SFM). Cottonseed meal was substituted isonitrogenously with SFM at 0, 12, 24 and 36% levels in four rations viz. A, B, C and D. Daily feed consumption was 5.07, 4.30, 4.17 and 3.20 kg, while daily weight gain was recorded to be 0.98, 0.74, 0.57 and 0.33 kg under rations A, B, C and D, respectively. In the digestibility and nitrogen balance trial using eight calves, digestibility of organic matter was 63.2, 62.9, 62.1 and 61.7, respectively. Nitrogen retained as percent of intake did not differ significantly. Sunflower meal was purchased at half the price of CSM but economics of weight gain did not favor SFM inclusion in rations. Results suggested that SFM should not be fed to buffalo calves gaining more than 0.7 kg/day.

• Asian-Australasian Journal of Animal Sciences
• /
• v.14 no.8
• /
• pp.1125-1128
• /
• 2001

The objectives of this study were to evaluate the effects of feeding undegradable intake protein (VIP) on body weight changes and the return to estrus of Awassi ewes during the early postpartum period. Twenty multiparous Awassi ewes $(BW=57.4{\pm}3.0kg)$ were randomly assigned to two dietary treatment (10 ewes per treatment) for 4 weeks in a completely randomized design. Experimental diets were isonitrogenous, isocaloric, and were formulated to contain either 20% (CON) or 35% (SBM) of the dietary CP as UIP. On day $9{\pm}3$ postpartum (day 0=parturition) ewes were housed in individual pens. Feed intake was recorded daily. Dry matter intake (DMI), organic matter intake (OMI), crude protein intake (CPI), undegradable protein intake (UPI) and metabolizable energy intake (MEI) were higher (p<0.05) for ewes on SBM diets compared with ewes on CON diet. Ewes receiving SBM diet gained more (p<0.05) weight than the controls (5.3 vs 0.5 kg). There was a tendency (p>0.10) for SBM ewes to have more luteal activity than the controls. Ewes in the SBM group came into estrus 4 days earlier than CON ewes (p<0.10). These results indicate that Awassi ewes receiving adequate nutrition are capable of returning to estrus one month postpartum thus posing the possibility of being able to lamb every 6 months.

• KSBB Journal
• /
• v.23 no.2
• /
• pp.169-176
• /
• 2008

The concentration of fresh gel from Aloe vera L. by using ulfrafiltration (UF) process was investigated and analyzed. The two membranes (organic and ceramic) with different molecular weight cut-off (MWCO) and modules (flat sheet and tubular) was used. Under optimum operation conditions, ceramic (zirconium dioxide) tubular membrane with MWCO of 50 kDa resulted in higher flux, less fouling, more turbid, higher total solid, higher polysaccharide and less aloin content. Optimum operation conditions were transmembrane pressure of 1.0 bar, feed velocity of 240 L/hr and temperature of $23^{\circ}C$. Volume concentration factor of aloe gel was 3.13 at permeate flux of $51.1\;L/m^2{\cdot}hr$ after processing time of 1.66 hr. Aloin in fresh aloe gel by UF process was effectively removed as permeate and bioactive polysaccharide content was 2.1 times higher than that of fresh aloe gel. These results allowed a very good level of concentration degree and polysaccharide content. Thus, ultrafiltration process of this study was suitable for the concentration of fresh aloe gel though the aloe concentrate showed both the viscosity decrease and partially separation of liquid layer during storage at $4^{\circ}C$.

• Microbiology and Biotechnology Letters
• /
• v.32 no.4
• /
• pp.352-355
• /
• 2004

The extracts from 70 different plant natural products were used to investigate the antimicrobial activities against Brachyspira hyodrsenteriae, the causative agent of swine dysentery. Among them, the extracts from Terminalia chehula exhibited the highest antimicrobial activities against B. hyodysenteriae. It showed the antimicrobial activity against B. hyodysensteriae mostly in parts of its shell. Minimum inhibitory concentration (MIC) of the water extracts of T chehula was 12.5 mg/ml. After organic solvent extractions, the ethylacetate extracts exhibited higher antimicrobial activities against B. hyodysenteriae, and their antimicroactivities were similar to that of the tannin. In conclusion, these findings suggest that the extracts from T chebula may be used as animal feed additives for their antimicrobial activities against B. hyodysenteriae.

• Applied Chemistry for Engineering
• /
• v.4 no.2
• /
• pp.300-307
• /
• 1993

The phase-transfer polymerization of methyl methacrylate with tricaprylmethylammonium chloride-$Na_2S_2O_4-CCl_4$ initiator system was investigated in an aqueous-organic two-phase system. The observed rates of polymerization were compared with those obtained from the polymerization mechanism proposed with a cyclic phase-transfer initiation step. The rate of polymerization was found to be proportional to the concentration of $Q^+$ and square root of ${S_2O_4}^{-2}$ in the aqueous solution and the feed quantity of $CCl_4$ and MMA.

• Applied Chemistry for Engineering
• /
• v.3 no.2
• /
• pp.327-334
• /
• 1992

As a promising method for the volume reduction of the low-level liquid waste, the pervaporation process was studied using a cellulose acetate membrane. Experimental results showed that the pervaporation method, usually applied to separation of organic materials, has a good decontamination effect for the volume reduction of liquid waste and the evaporation rate of water in this process was markedly faster than that of natural evaporation method, a wide-used process for the volume reduction of liquid waste. Depending on the feed solution conditions, the pervaporation characteristics were evaluated by the experimental results and the optimum conditions for preparation of the cellulose acetate membrane were established to increase the pervaporation flux through the membrane.