Muhammad Nur

Ozone production by Dielectric Barrier Discharge Plasma for microbial inactvation in rice

Research on ozone production by using silent plasma or Dielectric Barrier Discharge Plasma (DBDP) and implemented for microbial inactivation in rice has been done. The plasma reactor for ozone generating were reactor with multi-point-plane (MP-P) reactor and spiral-cylender (S-C) reactor configurations. The high voltage AC has been used with voltage up to 40 kV and maximum frequency 23 kHz. For implementation in rice, this research used a Randomized Block Design (RBD) with 5 treatments and 4 replications in each treatment. Exposure time was varied such as: 0, 30, 60, 90, and 120 minutes. Total bacteria and molds (fungi) has been detected by using Total Plate Count (TPC) methods with nutrient broth as media for bacteria and, we found that MP-P Reactor needed less voltage comparing with S-C Reactor for the same cocentration ozone. Ozone generated by DBDP can reduce the population of bacteria and fungi in rice. The exposure for 90 minutes can eliminate 58.41% population of bacteria, and 26.23% population of fungi. Through analysis of variance known that ozone treatment is significantly affect the total bacteria at significance level of 5% and 1% (P <;0.05). However, treatment of fungi shown no significant effect, even at the 5% significance level (P> 0.05). Subtances of water, fat, and protein in rice was not change before and after ozone treatment.

Power consumption analysis DBD plasma ozone generator

Studies on the consumption of energy by an ozone generator with various constructions electrodes of dielectric barrier discharge plasma (DBDP) reactor has been carried out. This research was done to get the configuration of the reactor, that is capable to produce high ozone concentrations with low energy consumption. BDBP reactors were constructed by spiral- cylindrical configuration, plasma ozone was generated by high voltage AC voltage up to 25 kV and maximum frequency of 23 kHz. The reactor consists of an active electrode in the form of a spiral-shaped with variation diameter Dc, and it was made by using copper wire with diameter Dw. In this research, we variated number of loops coil windings N as well as Dc and Dw. Ozone concentrations greater when the wires diameter Dw and the diameter of the coil windings applied was greater. We found that impedance greater will minimize the concentration of ozone, in contrary to the greater capacitance will increase the concentration of ozone. The ozone concentrations increase with augmenting of power. Maximum power is effective at DBD reactor spiral-cylinder is on the Dc = 20 mm, Dw = 1.2 mm, and the number of coil windings N = 10 loops with the resulting concentration is greater than 20 ppm and it consumes energy of 177.60 watts

Study of an Atmospheric Pressure Plasma Jet of Argon Generated by Column Dielectric Barrier Discharge

An atmospheric of argon plasma jet was generated by using column dielectric barrier discharge has been investigated. In this study, argon gas was passed through the capillary column by regulating the flow rate of gas. This atmospheric pressure plasma jet (APPJ) was generated by a sinusoidal AC high voltage in the range of 0.4 kV to 10 kV and at frequencies of 15 kHz and 26 kHz. APPJ has been produced with flow rate of argon gas from 1 litter/min - 10 litters/min. The electric current has been taken with variation of voltage and each interval argon gas flow rate of 1 litter/min. The results show that electric current increase linearly and then it trends to saturation condition by the increasing of applied voltage. We found also that the length of the plasma jet increase by augmenting of applied voltage both for frequencies of 15 kHz and 26 kHz. Furthermore, our results show that length of plasma jet optimum for flow rate of argon gas of 2 litters/minute. In addition, we obtained that the larger applied voltage, the greater the temperature of the plasma jet.

Dielectric barrier discharge plasma reactor analysis as ozone generator

Ozone generator by using dielectric barrier discharge plasma (DBDP) has been studied. DBDP reactor was constructed with spiral cylender configuration. We found that ozone concentration increased with increasing of voltage, number of spools coil. The ozone concentration decreases with increasing distance between spiral electrode and cylender electrode. We found something very interesting in the generation of ozone, where electrc current has been measured, in other words ionization has occurred, but ozone was not formed. It can be interpreted that although ionization has occurred but oxygen molecular dissociation has not happened or is not enough for the formation of ozone.

Development of ozone technology fish storage systems for improving quality fish production

Development of ozone technology fish storage system (OTFIS) to maintain the quality of the fish has been done. The ozone technology fish storage system (OTFIS) can be applied in the fishing boat, fish storage in the Fish Auction Market, fish storage in the means transport for fish. In this research, we produced a prototype that was integrated by the fish container and ozone generator. We used Dielectric Barrier Discharge Plasma (DBDP) technology for ozone generator. The characterization of ozone generator has been carried out and showed that ozone generator can produce ozone concentration from 0.5 ppm to 12 ppm. The ozone concentration in the area is very suitable to be used in food technology. The ozone treatment was performed on red tilapia representing the white-fleshed fish with ozone concentrations from 0.5 ppm to 4.5 ppm. The results of this treatment showed that organoleptic and TVBN of fish were still appropriate with Indonesian National Standard (INS). Beside that, TPC testing has been done on the red tilapia showed that the higher the ozone concentration the smaller the remaining of bacteria colonies. Similarly, for a variable of time, the longer the exposure to ozone the less the remaining of colonies. The results of this study have been adapted to realize of OTFIS with a size of 50 cm × 50 cm × 100 cm (250 liters) and can accommodate as much as 100 kg of fish.

Study of ozone reactor with dielectric barrier discharge plasma (BDBP): variations of inner electrode based on Stainless steel, Galvalume, and Copper

The research of ozone reactor with dielectric barrier discharge plasma (BDBP) with variations of inner electrode based on stainless steel, galvalume, and copper has been done. The ozone was produced with oxygen as inputted gas. The ozone concentration has determined with variations of voltage (from 3 to 5 kV) and flow rate (i.e. 2,3,4,5,6,8 and 10 L/min). Ozone reactor, has a frame with cylinder-cylinder configuration. Inner electrode (cylindrical) made of stainless steel, galvalume and copper. The three of materials was used for evaluates the inner electrodes corrosion resistance characteristics for DBDP reactor. The outer electrodes (cylindrical) made of zinc plate, while Pyrex used as dielectric material. AC High Voltage was used as power supply with frequency of 16 kHz. This research has been conducted with five variations of reactors length of 5, 10, 15, 20, and 25 cm. The ozone concentration has measured with KI solution and then titrated using sodium thiosulphate. After used as the inner materials of ozone reactor, the corrosion test has been conducted with SEM and EDX analysis. The results showed that ozone concentration was increasing by the increasing of voltage, and the greater gas flow rate gives the less ozone concentration. In addition, the most corrosion electrodes is one made of copper, which supported by SEM EDX result, that has CuO concentration of 60,77%. Otherwise, from the three of materials, stainless steel is obtained as the most stainless material.

Heating value prediction for combustible fraction of municipal solid waste in Semarang using backpropagation neural network

Backpropgation neural network was trained to predict of combustible fraction heating value of MSW from the physical composition. Waste-to-Energy (WtE) is a viable option for municipal solid waste (MSW) management. The influence of the heating value of municipal solid waste (MSW) is very important on the implementation of WtE systems. As MSW is heterogeneous material, direct heating value measurements are often not feasible. In this study an empirical model was developed to describe the heating value of the combustible fraction of municipal solid waste as a function of its physical composition of MSW using backpropagation neural network. Sampling process was carried out at Jatibarang landfill. The weight of each sorting sample taken from each discharged MSW vehicle load is 100 kg. The MSW physical components were grouped into paper wastes, absorbent hygiene product waste, styrofoam waste, HD plastic waste, plastic waste, rubber waste, textile waste, wood waste, yard wastes, kitchen waste, coco waste, and miscellaneous combustible waste. Network was trained by 24 datasets with 1200, 769, and 210 epochs. The results of this analysis showed that the correlation from the physical composition is better than multiple regression method .