Development and Application Characteristics of High Gradient Magnetic Separator

As one of the most effective techniques for fine particle processing, high gradient magnetic separation is mainly used in the separation and enrichment of fine and weak magnetic particles and other important industrial fields. High gradient magnetic separator is a new type of high intensity magnetic separator, which has strong ability to capture fine and weak magnetic particles, developed on the basis of ordinary high intensity magnetic separator. Based on the early periodic- high -gradient magnetic separators, the optimization development direction of high gradient magnetic separators and their application characteristics of various high gradient magnetic separators in these decades were summarized, and the future development directions of high gradient magnetic separator were presented.

Photodegradation of Dyes From Cual Batik Waste Using TiO2 Photocatalyst From Ilmenite Bangka

Cual batik is one of the local products of the Bangka Belitung Islands. The expansion of cual batik in Bangka Belitung continues to increase, resulting in an increase in the production of cual batik cloth. Cual batik contains remasol dyes which are carcinogenic so that waste handling is appropriate and safe for the surrounding environment. One of them is using the TiO2 photocatalytic method from ilmenite Bangka. The results of XRF characterization showed that the TiO2 content after magnetic separator and HCl washing reached 69,975% and 77,260%. The results of XRD characterization showed that the optimal temperature of calcination was at 700ºC with the peak diffraction intensity of anatase TiO2 crystals at 2θ 48.9º, 53.53º and 53.92º. In FTIR characterization, there is a functional group spectrum of titanium dioxide (TiO2) at the absorption wave number 795 cm-1 showing Ti-O-Ti stretching vibrations, at wavenumber 2326 cm-1 showing Ti-O stretching vibrations. The results of photodegradation of cual batik waste showed a decrease in the dye content of remazol briliant blue when exposed to UV lamps and sunlight at contact times of 30, 60, and 90 minutes 85.21%, 82,75%, and 86,72% (UV light); 70,75%, 78,92%, and 93.51% (sunlight).

Components’ Characterization of End-of-Life Dishwashers

The treatment of Wastes of Electrical and Electronic Equipment (WEEE) is a significant source of secondary raw materials. Ferrous and non-ferrous metals, electronic equipment, and plastics are among these materials. One of the most common metals sourced out of WEEE is stainless steel. Dishwashers are common sources of stainless steel, so large amounts of stainless steel can be recovered from them. In this project, dishwashers were submitted to size reduction via shredding, and the shredded products went through a magnetic separator (which separates all the magnetic ferrous components), an eddy current sensor (which separates all the non-ferrous components) and an induction sorting sensor (which removed all the metallic fractions). This procedure led to the following two streams: one with stainless steel, boards, and cables and another stream mainly including plastic. In the next stage, the stainless-steel stream passed through a high-intensity magnetic separator, leading to a magnetic and a non-magnetic stream. Thereafter, hand sorting was applied to both streams which aimed to increase the recovery from each stream.

Visual Quantitation of Copper Ions Based on a Microfluidic Particle Dam Reflecting the Cu(II)-Catalyzed Oxidative Damage of DNA

Due to the use of copper water pipes and the discharge of industrial wastewater, contamination of copper ions in drinking water has become a severe hazard globally. To routinely check water safety on a daily basis, easy-to-use platforms for quantitative analysis of trace amounts of copper ions (Cu2+) in drinking water is needed. Here, we report microfluidic particle accumulation integrated with a Cu(II)-catalyzed Fenton reaction for visual and quantitative copper ion detection. Microparticles (MMPs) and polystyrene microparticles (PMPs) are connected via a single strand DNA, MB155. However, when Cu2+ is present, MB155 is cleaved by hydroxyl free radicals (•OH) produced from Cu2+/hydrogen peroxide (H2O2) Fenton reactions, causing an increased amount of free PMPs. To visually count them, the particle solution is loaded onto a microfluidic chip where free MMPs and MMPs–MB155–PMPs can be collected by the magnetic separator, while the free PMPs continue flowing until being accumulated at the particle dam. The results showed a good linear relationship between the trapping length of PMP accumulation and the Cu2+ concentration from 0 to 300 nM. A limit of detection (LOD) of 70.1 nM was achieved, which is approximately 449 times lower than the 2 × 103 μg·L−1 (~31.5 μM) required by the World Health Organization (WHO). Moreover, the results showed high selectivity and good tolerance to pH and hardness, indicating compatibility for detection in tap water, suggesting a potential platform for the routine monitoring of copper contamination in drinking water.

Optimization of Airflow Field for Pneumatic Drum Magnetic Separator to Improve the Separation Efficiency

Traditional dry magnetic separation has poor separation efficiency for fine-grained materials, and combining airflow and a magnetic field may be one of the most effective means to improve it. Based on the pneumatic drum magnetic separator developed by our team, an improved pneumatic magnetic separator with a segmented flow field is proposed, which pushes materials to move along the separation surface. Analysis of flow field in the separation zone and the forces on particles show that the improved pneumatic magnetic separator makes it easier to collect fine magnetic particles, while nonmagnetic particles are more easily removed by airflow. Separation test results also show that the iron grade and the recovery of concentrate improved from 37.89% and 74.75% to 51.76% and 91.79%, respectively. The separation efficiency of the pneumatic drum magnetic separator has been remarkably improved by optimizing airflow field in the separation zone.

Optimization of ilmenite ore processing using induced roll magnetic separator

PT Timah Tbk has been processing residual ore (SHP) with a low tin grade of ± 10-30% wt. To increase tins grade and associated mineral products to be a high grade (> 70% wt), an evaluation and optimization process is needed on Induced Roll Magnetic Separator processing equipment. The evaluation and optimization process was carried out on magnetic products, especially ilmenite minerals. Sampling is done on the feed and the product based on the tool parameter settings. The feed rate is set at 380, 320, 250, 420, and 470 gr/10s. The splitter opening is set at 10, 15, 20 mm of magnetic rollers. While the electric current is set at 2, 4, 6, 8, 10, 12, 14 amperes. Mass and grade data are then analyzed by regression and variance statistical methods and optimized by the response surface method. The evaluation results show that only the splitter opening parameters and electric current strength are significant in explaining the product results obtained with a level of hypothesis error of 5%. The results of IRMS optimization show that the best parameter conditions are in the 2-4 ampere of electric current and 10-15 mm of splitter openings with illmenite grade capable of> 80% wt in the second order of central composite design.