A multi-criteria proximal bundle-based optimization approach to chick-mash feed formulation

The development of feed formulation is essentially a problem of optimization which involves selecting the best alternative, starting from a specified set of possibilities. This study is aimed at developing a generic decision supporting system for optimizing the poultry feed production through the application of multi-objective proximal bundle approach, taking into consideration the energy optimization, limiting the amino acid variation and providing a least cost of production. A non-differentiable interactive multi-objective bundle-based optimization method was used in solving this problem. This technique provided a wide range of alternatives choices for the decision maker to formulate an effective and optimum feed that will minimize the costs, achieve more balanced ration, limit the methionine variation for growth, and optimize the metabolized energy based on feed at his/her disposal. The algorithm of this method is based on the objective functions classification. According to this classification, a new (multi-objective) optimization problem was formed and solved by a Multi-objective Proximal Bundle method. The method in turn generated different alternative formulations from which the decision maker arrived at the final decisio

Hydrophobic mullite ceramic hollow fibre membrane (Hy-MHFM) for seawater desalination via direct contact membrane distillation (DCMD)

A low-cost hydrophobic mullite hollow fibre membrane (Hy-MHFM) fabricated via phase inversion/sintering technique followed by fluoroalkyl silane (FAS) grafting is presented in this study. The prepared CHFMs were characterized before and after the grafting step using different characterization techniques. The pore size of the CHFM surface was also determined using ImageJ software. The desalination performance of the grafted membrane was evaluated in direct contact membrane distillation (DCMD) using synthetic seawater of varying salt concentrations for 2 h at various feedwater temperatures. The outcome of the evaluations showed declines in the permeate flux of the membrane at increasing feed concentration, as well as increased flux with increased feed temperature. The long-term stability of the membrane was achieved at time 20 h, feed temperature 60 °C, and permeate temperature 10 °C, the membrane achieved a salt rejection performance of about 99.99 % and a water flux value of 22.51 kg/ m2 h

A Multi-Criteria Proximal Bundle-based Optimization Approach to Chick-Mash Feed Formulation

ABSTRACT The development of feed formulation is essentially a problem of optimization which involves selecting the best alternative, starting from a specified set of possibilities. This study is aimed at developing a generic decision supporting system for optimizing the poultry feed production through the application of multi-objective proximal bundle approach, taking into consideration the energy optimization, limiting the amino acid variation and providing a least cost of production. A non-differentiable interactive multi-objective bundle-based optimization method was used in solving this problem. This technique provided a wide range of alternatives choices for the decision maker to formulate an effective and optimum feed that will minimize the costs, achieve more balanced ration, limit the methionine variation for growth, and optimize the metabolized energy based on feed at his/her disposal. The algorithm of this method is based on the objective functions classification. According to this classification, a new (multi-objective) optimization problem was formed and solved by a Multi-objective Proximal Bundle method. The method in turn generated different alternative formulations from which the decision maker arrived at the final decision. The results were displayed as value path according to their range of values, and from the lists of alternatives, it is clear that none of the alternatives can be better improved without impairing others. At this point the decision maker will now make a choice from the list, based on his preference. This is done by ranking the three objectives according to the decision maker's order of preference. The decision maker must therefore be willing to sacrifice something. This work therefore provided a platform to provide solution to the problem of conflicting objectives of energy optimization, limiting amino acid variation and ration cost minimization in feed formulation

Development of high strength, porous mullite ceramic hollow fiber membrane for treatment of oily wastewater

Ceramic hollow fiber membranes (CHFMs) are known for their excellent characteristics including high surface area, compact design, and good chemical, thermal, and mechanical stabilities. Despite these interesting attributes, CHFMs are also prone to certain limitations, such as brittleness and high cost that hinder them from being commercialized. To mitigate this drawback, we have developed a high strength, porous ceramic hollow fiber membrane, derived from mullite–kaolinite powder, for efficient oil–wastewater separation. The superhydrophilic, low-cost mullite-based (CHFM) was successfully fabricated through combined phase inversion and sintering techniques. Prior to the fabrication, the as-received mullite–kaolinite was characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and Brunauer–Emmett–Teller (BET) analyses. Subsequently, operational parameters such as the effect of mullite content, sintering temperature, and air gap were optimized during the fabrication of mullite ceramic hollow fiber membrane. The resulting membranes were systematically characterized and evaluated in terms of morphology, porosity, mechanical strength, water flux, and oil–water separation. Increasing the mullite content, air gap, and sintering temperature enhanced the formation of microvoid structure. It is interesting to note that the mechanical strength of 86 MPa was obtained for the membrane containing 60 wt % of mullite sintered at 1450 °C and an air gap of 5 cm. The membrane induced a stable permeate water flux and oil rejection of mullite CHFM of 182 L/m2·h and 97.1%, respectively. As compared to kaolin ceramic counterparts, this porous mullite ceramic hollow fiber membrane can be used in various water treatment applications, including for the separation of oily wastewater due to its mechanical strength and water flux

Hydrophobic silica sand ceramic hollow fiber membrane for desalination via direct contact membrane distillation

A porous hollow fibre ceramic membrane derived from a low-cost natural material (silica sand) and fabricated by combine phase inversion and sintering technique followed by fluoroalkylsilane (FAS17) grafting to improve its hydrophobicity is reported in this study. Prior to the subjection of the silica sand ceramic hollow fibre membrane (SSCHFM) to a desalination performance test via direct contact membrane distillation (DCMD), characterization studies were performed on the SSCHFM before and after grafting using different characterization techniques, such as scanning electron microscopy (SEM), atomic force microscopy (AFM), 3-points bending, water liquid entry pressure (LEPw), and water contact angle measurement. Mercury porosimetry analysis (MIP) was also used to determine the pore size distribution and porosity of the SSCHFM. The grafting process caused an increasing of the contact angle from 0° to 142.5° ± 2.0, and LEPw value of (2.6 ± 0.4 bar) was achieved. AFM images showed an increment in the surface roughness of the grafted SSCHFM from 0.305 µm to 0.375 µm, with a slight decrease in the average pore size and porosity from 0.17 µm and 17% to 0.12 µm and 14.7% respectively. After the grafting process, the performance of the membrane in DCMD was evaluated on a salt solution for 32 h at different NaCl concentrations (8,16, 24, 32 and 40) g/L, feed flow rates and feed temperatures. The results showed a decrease in the permeate flux at increasing feed concentration, but the reverse was at higher feed flow rates and feed temperatures. The surface-modified membrane recorded a water flux value of 35 kg/m2.h and 100% salt rejection. The results indicate that the hydrophobic hollow fibre ceramic membranes derived from silica sand have significant potential to be developed for membrane distillation application in water purification and reclamation

Novel silica sand hollow fibre ceramic membrane for oily wastewater treatment

Hollow fibre ceramic membranes are well-known to have unique characteristics, including superior thermal, chemical, and mechanical stabilities. The main drawback of ceramic membranes that limits their commercialisation is their high cost of raw materials. To overcome this disadvantage, a low-cost silica sand-based hollow fibre ceramic membrane (SS-HFCM) was successfully fabricated via combined phase inversion/sintering technique. Prior to fabrication, silica sand powder was first characterised using X-ray fluorescence (XRF), X-ray diffraction (XRD), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET), and Fourier transform infrared spectroscopy (FTIR) analyses. Furthermore, the morphology and mechanical strength were investigated using scanning electron microscopy (SEM) and three-point bending test, respectively. The effects of two major fabrication process parameters (i.e., sintering temperature and ceramic content) on the mechanical strength, morphology, pure water flux (PWF), and oily-water separation of the SS-HFCM were examined. Based on the findings, the most suitable sintering temperature was 1300 °C. Satisfactory morphological structure and strength of sponge- and finger-like voids at 55 wt% ceramic powder loading was found to be advantageous for the characteristics of the fabricated SS-HFCM. The mechanical strength of 210 MPa was obtained at the sintering temperature and content loading of 1300 °C and 57.5 wt%, respectively. The mechanical strength of SS-HFCM obtained at 1300 °C in this work is significantly higher than those reported in previous studies. Furthermore, enhanced oil-water separation performance was obtained with the highest oil rejection rate of 99.7%. This SS-HFCM has a satisfactory structure with functional inner and outer layers of separation, which can be beneficial for water treatment applications, such as microfiltration, ultrafiltration, membrane distillation, and membrane contactor

Hydrophobic mullite ceramic hollow fibre membrane (Hy-MHFM) for seawater desalination via direct contact membrane distillation (DCMD)

A low-cost hydrophobic mullite hollow fibre membrane (Hy-MHFM) fabricated via phase inversion/sintering technique followed by fluoroalkyl silane (FAS) grafting is presented in this study. The prepared CHFMs were characterized before and after the grafting step using different characterization techniques. The pore size of the CHFM surface was also determined using ImageJ software. The desalination performance of the grafted membrane was evaluated in direct contact membrane distillation (DCMD) using synthetic seawater of varying salt concentrations for 2 h at various feedwater temperatures. The outcome of the evaluations showed declines in the permeate flux of the membrane at increasing feed concentration, as well as increased flux with increased feed temperature. The long-term stability of the membrane was achieved at time 20 h, feed temperature 60 °C, and permeate temperature 10 °C, the membrane achieved a salt rejection performance of about 99.99 % and a water flux value of 22.51 kg/ m2 h