Application of Distributed Control System in Fermentation Section of Pharmaceutical Enterprises

Author: Ju-hong Zhu Lv Yongjun


At present, most of the fermentation processes in the domestic pharmaceutical industry are still in the traditional stage, manual operation, experience control, not only the operator's labor intensity, low work efficiency, high energy consumption, but also lack of scientific production, subject to human factors, easy to make mistakes And will cause serious economic losses. This paper describes the application of distributed control system (DCS) in the fermentation process of pharmaceutical companies.

Distributed Control System (DCS) is a decentralized integrated control system that integrates advanced technologies such as computer technology, network technology, automatic control technology, redundancy and self-diagnosis technology. The interface is friendly, powerful, high reliability, easy to operate, flexible in configuration, and has strong applicability.

The fermentation process is a very complicated process. During the fermentation process, it must maintain a certain culture temperature, provide suitable oxygen, and timely supplement the nutrients needed for the growth of the strain. Therefore, it is required to effectively control the temperature and humidity of the inlet air, the temperature of the fermentation liquid and the dissolved oxygen content, and to feed when necessary.

First, the system's hardware configuration

(1) System block diagram

(2) System configuration (main equipment)

1. A set of distributed control system (DCS), including: DCS control station, DCS operation station and system control software.

2. Input and output mechanisms, including: temperature transmitter, pressure transmitter, flow transmitter, differential pressure transmitter, dissolved oxygen meter, pneumatic regulating valve, solenoid valve, speed controller, intelligent control box, etc.

(III) Introduction to the main functions of the system

1. Input section

The input part is mainly composed of temperature transmitter, pressure transmitter, flow transmitter, differential pressure transmitter and dissolved oxygen meter, which completes sampling and conversion of the on-site signal, and forms a standard signal to be sent to the control station for analysis and processing.

2. Control station

The control station is composed of a power box and a cage. The cage is equipped with various types of input, output and main control cards to complete the signal processing and calculation of the input part, and the display information is sent to the operation station through the Scnet network. Perform arithmetic processing according to the configured control scheme and issue control data to the actuator. The control station can also receive operational commands from the operator station and convert them into control data for output to the actuator.

3. Executive agency

The actuator is mainly composed of a pneumatic regulating valve, an electric valve, a speed controller and an intelligent control cabinet, and is used for receiving operation data sent by the control station, performing on-site operations, and completing the automatic control process.

4. Operator station

The operation station is composed of industrial PC, display and Scnet network card. It realizes real-time communication with the control station through Scnet network, completes system configuration, control configuration, control scheme and operation information download, and accepts the scene returned by the control station. The data is displayed in real time and recorded to form historical data for query.

Second, the system software configuration

(1) System requirements to run under windows95/98

(2) Distributed control software

Including: configuration software, flow chart design software, real-time monitoring software and /. user-defined language.

Third, the process and control plan

The fermentation process is cultured in small tanks, medium tanks and large tanks. The fermentation process is an exothermic reaction. In the fermentation process, it is required to maintain a certain temperature, timely supplement nutrients, and control the dissolved oxygen.

The temperature and humidity of the inlet air are controlled by the cooling of the air cooler and the temperature rise of the air heater.

The dissolved oxygen content of the fermentation broth is controlled by varying the amount of air intake and changing the agitation speed of the fermentor.

Large tanks and medium tanks use adjustable refrigerant water to control temperature, and small tanks use regulated refrigerant water valves and steam valves to control temperature.

Fourth, the evaluation of system operation and control effects

Through the preliminary exploration and technical preparation work, we invested more than 700,000 yuan to carry out the one-month renovation, installation and commissioning work of the company's kanamycin fermentation section using the JX-300DCS system of Zhejiang University Central Control. After six months of trial operation. It shows that the system is reliable in operation, flexible in control and convenient in operation. The automatic control system has achieved the expected results and meets the requirements of the fermentation process. The entire system is stable. And achieved good economic and social benefits.

V. Benefit Analysis

(1) Saving energy

The fermentation workshop has large energy consumption and long-term continuous operation, so energy conservation is of great significance.

1. The amount of refrigerant water is reduced, so that the actual power produced by the refrigerant water is reduced from 40kw to 34kw, and the annual electricity consumption is 52,500kwh, and the annual cost can be saved by 31,500 yuan.

2. Reduce the amount of compressed air, so that the actual power consumption of the centrifugal air compressor is reduced from 612kw to 586kw, the annual electricity consumption is 22770kwh, and the annual savings can be 136620 yuan.

(2) Improvement of production level

After the automatic control transformation, the fermentation production level has been improved by the optimization of the process energy quantity, the average fermentation unit is increased by 1.8%, and the economic benefit of 252720 yuan per year can be produced. The two totals can generate economic benefits of 31500+136620+252720=420840 yuan per year. According to the above analysis, the investment payback period is about 17 months, which shows that the project is very investment value.

This transformation not only brought good economic benefits to the company, but also improved the level of industrial automation of our company. After the completion of this transformation, our company obtained the CIMS application engineering demonstration enterprise in Zhejiang Province, and reduced the human factors in traditional production. Make production more scientific, reduce the labor intensity of operators, and improve production efficiency. At the same time, it also laid a good foundation for the further development of industrial automation in our company.

    This classification summarizes the Organic Spirulina Phycocyanin produced by our own factory in northwestern of China .