Design And Implementation Of The Pharmaceutical Factory Workshop Environment Distributed Control System

Along with science and technology progress and economic development, people raise increasingly to the health request. Our government is also increasingly strict with the management of the drugs that relates directly to the people's health. In 1995, our country started to carry out Goodpractice in the Manufacture and Quality Control of Drug, GMP, GMP has strict request for the production environment and control of the pharmaceutical factory. The paper is to deal with the discussion of the technology of environmental control in the production of Johnson's Pharmaceutical Co Ltd.The control system in the production environment of the pharmaceutical factory is to put into effect the automatic control of temperature & humidity, cleanliness and differential pressure to meet with the requirements for GMP. Because of the wide range and the long-distant communication of the environmental control, and in consideration of its advancement, reliability, extensibility and economy, the system of the environment control applies the current distributed control system both in our country and abroad, which is the main points of this paper.First of all, the paper briefly introduces the dispersion control, centralized management, the openness, the extensibility and multi-layer architecture in distributed control system, and makes the detailed elaboration to the fieldbus technology and the communication protocol. At the same time the paper discusses such elements in our country's GMP as the medicine cleaning workshop's production environmental control, the cleanliness, the determination of air rate and the demand of indoor temperature & humidity control, differential pressure control, the air distribution. Meanwhile, in the light of the requirement of the pharmaceutical cleaning production environment, the paper introduces the purifying air-conditioning system's air purification processing method as well as the basic principle of variable air volume air-conditioning system and the composition. The paper analyzes enthalpy value control technology based on the enthalpy wet chart's, the PID control principle and the working principle of central air condition in detail.According to pharmaceutical production requirement, the paper thoroughly analyzes the characteristics of cleaning production environment, and applies the technology of distributed control system, fieldbus and direct digital controller to cleaning environmental control system, and designs a complete pharmaceutical production environmental control system.By applying dispersion control and centralized management, the system controls on-site devices to realize the control of temperature & humidity, differential pressure, air rate, and the cleanliness monitoring warning. The system has been put into use, and met with the design requirements.