Synthesis of Methanol Using Closed Thermodynamic Cycles

One of the most promising technological solutions for methanol production is a small-sized and autonomous process that allows reducing energy intensity through the efficient use of heat-flow energy. This article presents the technological development of a plant for small-scale methanol production, which includes processes for desulfurization of natural gas and synthesis of raw methanol. In the production of methanol directly in natural-gas production areas, full-cycle technology using low-temperature energy carriers is relevant for the implementation of drying and purification processes of natural gas. The purpose of this work is to present an approach to increasing the energy efficiency and environmental safety of the method for producing methanol. When developing the installation, the possibilities for rational use of the energy potential of heat flows, namely, converted gas and flue gas flows, are taken into account. In addition, the involvement of an absorption water–ammonia refrigeration unit in the technology makes it possible to provide low-temperature condensation by freezing out moisture from natural gas produced in any gas-condensate fields. It is shown that when organizing a process using closed thermodynamic cycles of material and heat flows with the possibility of maximum recovery and utilization of secondary energy resources, a reduction in specific energy costs by 10–12% is ensured in advance. The question remains open about the complete mathematical description of the process, which will make it possible to develop a control system for technological parameters in the region of optimal values in terms of the yield of the target product in specified volumes with minimal energy costs. The material presented in the article can be used in the petrochemical industry, in particular in the production of methanol near gas-condensate fields.