Innovative regenerable polyamide particles as new filter aids for wine lees filtration

In oenology, the conventional dead-end filtration with filter aids, used for the processing of wine lees, consumes a high quantity of diatomaceous earth and brings serious environmental, sanitary and economic implications. In a real concern to improve wine quality and to decrease pollution, the “ecological filtration” concept based on the utilisation of a regenerative filter aid is proposed in this study. Polyamide particles were investigated as innovative filter aids for wine lees filtration. Trials were performed with two grades of polyamide particles D80 (D50 = 91.8 µm) and D100 (D50 = 111 µm). Filtration was carried out with wine added with two concentrations of lees (10.8 % and 20.2 %). The impact on wine quality was determined with oenological analyses, showing that the filtration made with polyamide particles did not modify wine organoleptic characteristics, improved turbidity and the filtrate fluxes are higher in comparison to the usual precoat filtration. Then, polyamide particle regeneration experiments proved that these particles could be reused as filter aids several times after cleaning.

Principles of juice purification

The raw juice as obtained by juice extraction of sugar beet cossettes contains dissolved and insoluble impurities (nonsugars) which need to be removed as much as possible to enable a cost-effective production of the wanted quality of white crystal sugar. The most commonly used purification approach of beet raw juice is the so-called classical liming process. The aim and principles of the different successive process steps in juice purification will be outlined in this paper. The purification principles comprise several chemical-physical reactions of particular nonsugars in the juice which are initiated at first by the addition of milk of lime to the raw juice in preliming and main liming. Through injection of the carbon dioxide produced in the lime kiln in the 1st carbonatation calcium ions precipitate as calcium carbonate, which is then used as filter aid to remove by sedimentation and/or filtration the formed slurry. The remaining surplus of lime salts are finally removed in the 2nd carbonatation which after filtration results in a clear thin juice.

Increasing the Efficiency of Vacuum Belt Filter in Gol-E-Gohar Iron Ore Concentrate Production by Adding Surfactants

In this research, filtration experiments were carried out by four types of surfactants as filter aid. Sodium dodecyl sulfate and sodium lauryl ether sulfate as anionic surfactant (SDS and SLES), polyethylene glycol as nonionic surfactant (PEG) and cetyl trimethylammonium bromide as cationic surfactant (CTAB) were used to were used in order to evaluate their effects on moisture reduction of concentrate and improvement of the filtration process. All of the tests were done at the optimal conditions include 60 KPa vacuum pressure, 120 s filtration time, 105 microns particle size and 60% (w/w) solid content of pulp. Results showed that in all of the tests, cake moisture decreased by adding surfactants; however, anionic surfactants SDS and SLES were better than other chemicals. By adding 100 g/t SDS and SLES to the pulp, the filter cake moisture content was reduced by 2%. SDS and SLES improves filtration performance by increasing the ratio of throughput to moisture. At the concentration of 100 g per ton SDS and SLES, the highest throughput and lowest moisture was achieved. Although both of SDS and SLES have similar chemical structure and action, SLES was selected due to better solubility in hard water, economic justification and availability.

Effect of soy protein-based flocculant on flocculation and filtration of diatomite and kaolin suspensions

The effect of ethylated soy protein-based bioflocculant (EtSP) as a filter aid reagent was investigated. The efficiency of EtSP as a filter aid was evaluated in terms of the specific cake resistance, α, and was compared with chitosan and polyaluminum chloride (PAC). Diatomite and kaolin were used as model particles. Total filtration resistance, R, decreased with increasing flocculant dosage (wt.%, flocculant/particle) and was almost constant in the range of 1 wt.% or more for both particles. The α value was significantly decreased from 1.01 × 1011 to 9.01 × 1010 m/kg for diatomite and from 5.11 × 1010 to 5.20 × 109 m/kg for kaolin by the addition of EtSP in the case of 1.0 wt.%. The α value for cakes formed by EtSP was much smaller than that formed by chitosan and PAC. In the case of diatomite, in the dose range of 0.5–1.0 wt.%, the α value for cakes formed by EtSP and chitosan was almost the same. However, at the excess dose of 2.0 wt.% over, the α value formed by chitosan abruptly increased. In the case of kaolin, in the dose range of 1.0–2.0 wt.%, the α values of chitosan and PAC were mostly the same, however, these values were larger by ca. nine times than that of EtSP.

The Effect of Alum as Filter Conditioner on the Performance of Conventional Rapid Sand Filter

Filtration is a one of the most important and critical unit process followed worldwide which removes dirt particles from water. As the water quality standards are changing and becoming more stringent, the improvement in the performance of existing rapid sand filters is unavoidable. The use of filter conditioning to improve filter performance is a relatively recent development in drinking water treatment. Different advantages claimed by such use of filter aid includes lessening ripening period, superior turbidity removal and relatively stable filtrate quality. It also has limitations like reduction in filter run and comparatively higher back washing requirement. To assess the suitability of such method,under the existing conditions is of enormous importance.12 Current research explains the impact of filter media conditioning on the overall performance of conventional rapid sand filter. The study was carried out by installing a pilot plant at Ichalkaranji municipal water treatment plant. Different doses of alum as filter conditioner were tested and the comparison was made with the performance of conventional filter without filter aid. The parameters for evaluation were turbidity removal, filter run and backwash requirements. The dose of alum as filter conditioner was given as slug dose. The effect of zeta (ζ) potential change was observed to be one of the major reasons of the performance improvement, accelerating the surface removal since initial phase