Current environmental problems and industrial needs require the permanent modification and improvement of existing technologies or the implementation and design of the new technological methods. One of the most effective and cheapest ways to meet real practical requests and needs and new methods development can be a computer-aided simulation and technologies design. In turn, the cheapest way to develop simulation tool for a new chemical process is to use an integrated simulation environment, which incorporates all necessary functionality and thus can reduce the cost of the new model development. Chemical WorkBench is such integrated platform, which is opened for incorporation of new models of chemical processes. The Chemical WorkBench meets main requirements for the open simulation platform: a) integrity: the code includes the all essential tools, which are required for complete cycle of chemically-centered simulation – visual flowsheet designer, chemical reaction scheme generator, substance and chemical reaction databases, visual post-processor; b) modularity: the code is based on a modular principle which permits to construct technology chains or processes models from universal reactor modules simulating the separate steps of processes and easily add new reactor modules, which meet predefined module interface; c) built-in information support: the code includes extended databases of physical-chemical properties, which can be accessed by all reactors through the universal data objects.