Increasing the energy and economic indicators of the operation of enterprises using steam
Due to the intensive development of all industries over the past decades and the high European requirements for environmental standards, the issue of modernizing outdated and ineffective existing enterprises of the post-Soviet space is acute.
An enterprise for the production of autoclaved aerated concrete, hereinafter referred to as AGB, was chosen as the object of research. A trip was made to the site for personal acquaintance with the equipment and technology of the enterprise. On the territory of the plant there are two gas boilers with a nominal productivity of 17 tons of steam per hour, after which the high-temperature coolant is sent to the autoclaves for the purpose of heat treatment of workpieces from finely dispersed aluminum raw materials with a strongly alkaline cement or lime mortar, resulting in the formation of gaseous hydrogen, foaming cement mortar and output we have a finished product - AGB. After such a technological process, the steam becomes "crumpled" and, it would seem, loses its value as a heat carrier. Therefore, the waste steam was discharged into the atmosphere, thereby causing thermal pollution of the environment, not to mention the constant need for make-up water in the boiler circuit.
Based on the processing of the information received by the engineers of the commercial department of LLC NPP OPEKS Energosystems, a number of measures have been developed to increase the energy and environmental performance of the enterprise:
- To "drain" the steam after the autoclaves, it was proposed to install a centrifugal steam separator OPEKS-1-SC16-1-F100 manufactured by OPEKS Energosystems, which, due to centrifugal forces, will separate the steam from moisture particles, thereby giving it a high dryness coefficient "X"; Moisture is removed through the drainage hole at the bottom of the separator, where a thermodynamic-type condensate drain of the Japanese brand YOSHITAKE model TD-10NA DN20 is installed, the official distributor of which is OPEKS Energosystems.
After that, it is necessary to direct the dried steam into a shell-and-tube heat exchanger manufactured by OPEKS Energosystems to transfer energy in the form of heat to the make-up water to the deaerator installation so that the steam moves in the intertube space with minimal pressure loss, and the water in the coiled tubes, the design of which forces the flow turbulize over the entire heat exchange surface. For the actual effective operation of the TO, it is necessary to organize the heat exchange process in such a way as to ensure the minimum pressure loss of the crumpled steam and achieve its complete condensation on the outer surface of the tube to release the latent heat of the phase transition. Also, after the heat exchanger, it is planned to install a float steam trap of the Japanese brand YOSHITAKE model TSF-11F DN50 PN25.
The heat exchanger was calculated for the following parameters:
- Water inlet temperature = 50 0 С;
- Water outlet temperature = 95 0 С;
- Water consumption = 15 m 3 / hour = 4.17 kg / s;
- The amount of heat in this case is Q = 786 kW = 0.675 Gcal / hour.
By not complicated technical and economic calculations, we get the payback period of the proposed equipment about 3-4 months (quarter).
After the implementation of the above series of measures, we get:
- Saving money for obtaining the coolant of the make-up circuit;
- Instant increase in the energy and environmental performance of the enterprise;
- Efficient and high-quality heat exchange, steam-condensate equipment with a minimum payback period.
Thus, the complex of the above positive effects obtained gives us the right to assert that the modernization of enterprises using steam in technology is a reasonable and necessary measure that must be implemented at all existing plants.