Science: Technology:

An Optimal Bio-Processor Design for Environmental Solutions

By Dr. Keiji Taniguchi, Fukui University
and C.E.O. Hidekazu Noda, Noda Electric Corp.

1. Introduction

This paper deals with an optimal design technique for a bio-processor which changes organic wastes such as “remains of meals ” into fertilizers by utilizing the powerful decomposition effect of bacteria. By utilizing the self-heat-generation effect that occurs when the mixture of organic wastes, bacteria colonies and buffer material is heated, the temperature of the organic waste mixture actually becomes higher than that of the heat-source. By utilizing this phenomenon effectively, we can design a control system for the bio-processor which allows minimum use of the electrical power required for converting the organic wastes into fertilizers.

2. Experiment to Determine the Optimum Bio-Effect

The configuration of the bio-processor used for this experiment is shown in Figure 1. As depicted in the figure, the temperature of the heat-source, which is located at the bottom of the bio-processor, can be controlled by the reference value of the control system (see Figure1). In this case, the temperature of the surface of the heat-source is about 55°. The major operations for the bio-processor are as follows: initial mixtures of organic waste, colonies made by certain types of bacteria and buffer-material (rice husks, etc.), and bio-processing of the organic waste into the mixture. The weight ratio between the organic waste and the bacteria colonies with the buffer-material is roughly 1:1.

3. Self-Heat Generation and its Propagation in the Organic-Wastes

In this experiment, the temperature of the organic waste, bacteria colonies and buffer-material mixture is measured at positions A, B and C, as shown in Figure 1. These results are graphically illustrated in Figure 2 as a function of time. As is evident from Figure 2, the peak values , andof the temperatures at positions A, B and C of the organic waste, bacteria colonies and buffer-material mixtures, as shown in Figure1, actually become higher than that of the heat-source; concurrently, the peak temperature at position C has the highest value of the three.

After the heat energy values of the organic waste, bacteria colonies and buffer-material mixtures from the heat source was given, two processes are observed: first, an active self-heat-generation is caused in the organic waste, bacteria colonies and buffer-material mixtures at the vicinity of the heat-source; and then, the resulting heat energy propagates within the organic waste, bacteria colonies and buffer-material mixtures, from position A toward position C.

In this situation, the heat energy supplied from the heat-source into the organic waste, bacteria colonies and buffer-material mixtures equals zero. Figure 3 shows the current(A) supplied to the heat-source as a function of time (×5 sec).


4. Optimal Design for the Bio-Processor Controller

By using the results obtained from this experiment, it is evident that the optimal control system for the bio-processor must be designed in the following three stages:

1.      Initial mixture operation among organic wastes, colonies made by certain types of bacteria and buffer material,

2.      Bio-processing as described above, until the following condition  (is a constant value) is satisfied (See Fig.3),


3.      Drawing off of any water which was created as a by-product of the bio-processing. The water is drawn off as moisture by the use of a fan. The end of the bio-processing procedure can be determined calculations using the time constant of the temperature variation of organic wastes.

5.      Conclusion

An energy-efficient method of processing organic waste is described in this paper. The matter produced by this method can be used as fertilizers for agriculture.



(1) K.Taniguchi, H.Noda, M.Arakawa,Y.Noda, Y.Fujii and E.Son: A Low Power Consumption Bio-processor, P2002-210442A, July 30, 2002, Japan Patent Agency



BWW Society member Dr. Keiji Taniguchi is Honorary Professor at Japan's Fukui University as well as at Xi'an University of Technology in China. He first worked at Osaka Gear Works as a mechanical designer from 1952 to 1955, and then took a license of the First Class professional wireless communication engineer authorized by the ministry of the Japanese Government. As a result, he enlisted in the Japanese Air Force (JAF) in 1955, graduated from the officer candidate school of JAF in 1957, and then was an instructor of electronics and communications engineering from 1957 to 1964. His advanced grade was "First Lieutenant" in 1962. At the same time, he studied Electrical Engineering at the Night School of Kinki University in Japan, and received the B.E. degree in 1964. After resigning from JAF, he worked at Osaka University in Japan as a research associate from 1964 to 1973, while he was given the D.E. degree from Osaka University in 1972. He joined the Faculty of Engineering at Fukui University in Japan in 1973 as an associate professor, and was promoted to a Professor of Electronics Engineering in 1976. Since 1996 he has been an Honorary Professor of Xi'an University of Technology in China, and also an Honorary Professor of Fukui University since 2000. Dr. Taniguchi has been a consultant of Noda Electric Co. in Japan since 2000 and has been the technical advisor for Fukui Prefecture Government since 1981. He has also been a part-time professor of Tokyo Medical and Dentist University, Kyoto-Sosei University and Fukui Polytechnic College in Japan.

Dr. Taniguchi is the coauthor of 8 books concerning Image Processing, Signal Processing, Medical Electronics and Electronics Circuits. He is also the author or the coauthor of more than 140 technical papers published in refereed journal articles and proceedings. Furthermore, he is the editor, the author and the coauthor of three books, Fundamentals of Image Processing, published in 1996, Application to Image Processing, published in 1999 and Introduction to Signal Processing, published in 2001 (these titles are not contained in the 8 books cited above). Moreover, he is an inventor with 18 patents; his recent patents (USA) are related to the measuring devices for determining the amount of charge in toner particles. He is a Life Senior Member of the Institute of Electrical and Electronics Engineers in the United States and is also a Member of the Institute of Medical Imaging Technology in Japan.

Dr. Taniguchi has both licenses of an Instructor for skiing authorized by the Ski Association of Japan (SAJ) and a Coach for swimming authorized by the Swimming Association of Japan (NSR). He has been a member of SAJ since 1985. During the winter he has worked at Fukui Ski School authorized by SAJ as a part-time Instructor since 1988. In the swimming competition of Japanese Senior Olympic Meet held in Osaka in 2000, he has been awarded the silver and the copper medals in the butterfly stroke and the breast stroke respectively. He has also been awarded many gold, silver and copper medals in Master's Swimming Competition Meets in Japan since 1984. As another hobby, he has operated an amateur radio station with the call sign JA9OGI. Regarding his family, his father is Teijyu and his mother is Kazue (nee Ebara). Dr. Taniguchi and his wife, Junko (Ariki) have three children, Yoshikazu, Haruko and Teruaki, who lives in Bangkok and manages the training center of a new type of martial arts (Japanese name is  Sin-Kakuto-Jyutsu, "Taniguchi Do-Jyo").


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