Development of an alcohol content analyzer on a near-infrared by laser

Abstract

This project has the objective of developing an instrument to measure alcohol content using laser by reading the absorbance of near-infrared wavelengths of ethanol/water mixtures. The apparatus uses technology licensed by Tech Chrom Analytical Instruments in a photometer-based fuel analyzer. The major advantage of using near-infrared wavelengths is the ability to rapidly analyze mixtures in real-time without needing much preparation time while also not destroying the samples. An additional benefit is that the process can be done by a person without much training or technical skill. The main difference between the proposed product and the equipment currently used in industry for the purpose of alcohol content analysis will be that the price of the equipment is expected to be at least 50 percent less and the instrument will be manufactured in Brazil. The instrument's technical viability will be proved by means of a prototype using bench instrumentation where the sample's wavelength data will be calibrated and analyzed to validate the concept by determining alcohol content of various samples of anhydrous ethanol and industrial ethanol (with various ethanol/water mixtures). Different distilled beverages (vodka, cachaça, whisky, etc.) will also be tested to determine the viability of the devise for these applications. Several technological improvements will be used to improve the signal stability and resolution and the equipment will utilize a touch-screen interface to make it easier to use in alcohol production and industrial applications using alcohol as a raw material. Among the advances proposed for the project will be the use of a laser diode as the radiation source to improve the signal to noise ratio and the signal detection will be enhanced using lock-in amplification. Signal stability will be increased by the use of a reference signal (a dual-beam or internal reference of the internal laser photodiode). Additionally, the thermal stability of the sample will be maintained to insure repeatability of results. This is an electronic instrument and the software will be controlled by an internal microprocessor. Some of the electronics to be employed will be a power source, an electric supply for the laser diode, a PID (proportional-integral-derivative) temperature control, a signal conditioner for the detector, an amplification lock-in, an interface communication USB, and an LCD display. After the validation of the electronic circuitry is complete, there will be testing of the mechanics and optics involved, followed by the industrial design optimization of the equipment to insure ease of manufacture. An initial batch of four units will be made and tested in industrial applications to eliminate possible defects and compare its utility with current industry practice (AU)