| The Hexi Corridor district of Gansu is one of the best barley bases in China. The quality of barley malt plays an important role on its price. Therefore, the key development factor of the barley malt plant relies on promoting drying process technology and drying malt quality.In this paper, Ganpi No.4 is selected as the drying raw material, because it is the main strain of barley planted in the Hexi Corridor. The hot wind drying method is used in the cooperative plant of the research project, and the optimum drying process is applied as the technological basis of study, which was sought for many experiments by another research team of our project.The project aims to set up barley malt drying system. Under the condition of the present drying process and the plant's equipment, systematic control study and experiments were implemented with the emergy analysis method and heat transmission technology, based on the important principles of system engineering, automatic control and artificial intelligent control theory, and on the integrated technology of fluid numerical analogy, sensing and measurement, electronics, microcontroller and interface techniques, microcomputer control, fuzzy control, neural network control, virtual instrument, and motor speed control.The main results of this experimental study are as follows.1. While the drying room is chosen as a study object for the heating energy calculation, the results showed that the cylinder type of drying house has the dewatering capacity of 1330 kg/hr, and consumes 216384 m3 of wind volume every hour. The calculated results of energy balance showed that the drying system needs heat energy 11.81×105 kJ/h (kilojoules per hour).The computer modems analog and numeric simulations were completed by the software of ANSYS for the fluid dynamic analyses. The results showed that after drying winds enter the drying house, the velocity decreases gradually and has a little of increase where near the outlet, at the same time, two large vortexes are formed in the both left and right sides of the room. The maximum velocity occurs in the entrance. Therefore, it has been demonstrated that through altering the wing parameters of air blower, the resistant forces of wings will be reduced and also blowing efficiency will be improved.2. Barley malt drying experiments were carried out in a drying furnace, and a mathematical matrix, P=31.5He2.38V, was built up in relation to malt thickness (H, meter) and wind speed (V, m/s) as well as the air drag of malt (P, mmH2O).3. In the Zhongchuan Barley Malt Company, the emergy analyses conclusions of the drying ecological system follows. First, the circulation ratio of energy flow (CREF) and organic energy input are relatively lower, which shows the main input is inorganic energy and the industrialized level is high. Second, the emergy investment ratio (EIR) is generally lower, between 0.3 and 0.7, which means that the malt cost is lower and is strongly competitive. Third, the emergy yield ratio (EYR) trended upwards generally for these years, which shows the energy utilization efficiency is higher and economic competition power rises up continuously. Fourth, the environmental loading ratio(ELR) increases from 2.62×106 (in 2005) up to 3.94×106 (in 2009), which shows that pressure to the environment increases gradually and the plant development depends mainly on the energy input and consumption of unrenewable resources.4. A barley malt drying temperature and humidity control system design based on fuzzy logic control theory is introduced in this paper. The system hardware circuits with the AT89C51 controlling core were designed. The amplifying and regulating circuits were also designed attached with AD590 temperature sensors and HS1101 humidity sensors. A/D converter, keys and displaying circuit were expanded. Fuzzy algorithm, fuzzy control table and fuzzy controller were developed. Single-chip microcontroller controls frequency converter to drive air blower operation. In addition, inner RAM units of AT89C51 were distributed, and assembly language main program and 6 subprograms, such as data sampling and storing subprogram, digital filter subprogram, and fuzzy control subprogram etc., were developed accordingly.The results of the MATLAB analogue and control experiments showed that the control system has better stability and reliability, and has reached the accuracy requirements. The controlled temperature range is from 0 to 99℃, accuracy errors are between-0.25℃and +0.25℃, and average differences are less than±0.20℃in the confidence coefficient Kt of 4.3 (P=0.095). Additionally, the average relative humidity standard deviation (mean square error) is less than 0.30.5. To adapt to the microcomputer management of the plant, then a computer control drying system based on LabVIEW software of virtual instrument (VI) was designed. The hardware circuits and virtual instrument software, as data acquisition sub-VI and neural network PID control sub-VI etc., were developed. System simulation experiments showed that neural network PID control has good stationary and dynamic characteristics, and the system runs steadily.After the barley malt drying neural network PID control system based on LabVIEW experiments had been completed, the initial conclusions were that the average errors of the temperature control system are less than±0.20℃, and that the system has a highly stability and small overshoot.6. For three years of drying test operations on the microcontroller and microcomputer control system designed, with which the frequency converter is coupled with the driving motor, it has been shown that for each 1 tonne of barley malt production, an average of 1.5 tonne of water,0.05 tonne of coal, and 50 kW-hr of electricity are saved. Accounting for 20 ktonne of annual production of the barley malt plant, the drying process saves 946000 kW-hr of electricity and 2320000 kWh electric energy (all energy savings are converted to electricity quantities). Malt production saves 1129 tonne of standard coal per year. Compared to the former system, comprehensive energy saving is more than 14%.Therefore, this practical and experimental study improves the automation and intelligent levels of barley malt drying, and has the functions of energy saving and ecological efficiency.
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