The article covers methodology for construction of technological processes management systems using web technologies. The structure of modern management systems was analyzed, the emphasis was made on the higher management layer – SCADA-systems. The main advantages of distributed Web SCADA were presented in comparison to the desktop systems. Review of modern Web SCADA systems was made, their architecture, key components and interactions were investigated. Limitations in regard to application of existing Web SCADA systems to objects that demand constant optimization of management settings were displayed. Implementation of Web SCADA system using Arduino controller, based on the example of the absorption technological process was proposed. Algorithms for collection, storage, processing and visualization of process data were provided, as well as a mathematical model of absorber to calculate control actions. The interaction of SCADA with low-level controller was presented. Software components for SCADA were developed, based on open-source web-technologies such as: user interface (html + js), backend (php), database (mysql). Advantages of both the developed software and SCADA-systems in general were described. Recommendations and possible ways of implementation for Web-SCADA were provided.