We are specialists in the design and supply of Cogeneration Plants with gas engines, diesel engines or gas turbines.
– Cogeneration Plants with engines:
These cogeneration plants use gas, petroleum or fuel-oil as fuel. The heat recovery system is designed according to the requirements of the industry and is generally based on the production of low pressure steam, thermal oil and use of the high temperature cooling water circuit from the engine. The boiler is designed with a special supporting structure for resist the pulsating vibrations transmitted by the engine.
– Cogeneration Plants with gas turbines:
In gas turbines cogeneration plants, fuel is burned in a turbine generator that converts mechanical energy into electrical energy to produce electricity. These Gas turbine Cogeneration plants allow easy heat recovery and are economically profitable. The heat recovery boiler may have a post-combustion system incorporated into it to give greater flexibility for steam production.
We design, optimise and supply equipment for different cycles in cogeneration power plants:
• Simple cycle (chemical, food, pulp and paper mills)
The simple cogeneration system is equipped with a gas turbine generator and a waste heat recovery boiler, generating steam directly at the pressure of the process plant associated with cogeneration. It application is appropriate when the steam requirements are important.
• Combined cycle
The flue gases from the turbine go through the recovery boiler, where high pressure steam is produced. This steam expands in a steam turbine producing additional electrical energy. There will be low pressure steam at the turbine outlet, which can be used as such or condensed in a pressurised condenser, producing hot water or superheated water, which will be used in the associated industry. For this type of cycle, if the demand for heat decreases, the excess steam in the outlet of the turbine could be condensed, so that all the energy in the gases will not be lost but at least a certain amount of electricity will be produced.
Trigeneration plants jointly generate heat, electricity and cooling.
When there is a significant cooling requirement near a cogeneration plant, the implementation of a trigeneration plant may be feasible.
A trigeneration system optimize very high energy efficiency and reduces the energy cost of productive processes where significant amounts of waste heat in the form of steam or hot water, cooling and electrical energy are required.
• ORC Cycle : Organic Rankine Cycle
Aitesa has carried out several studies on ORC cycles (Organic Rankine Cycle) for the glass industry, electrical power generation and cement works.
The organic Rankine cycle uses an organic fluid (oil) to create a liquid-steam phase change at a lower temperature than in a traditional water-steam cycle. Due to the physical properties of the organic fluid, the expansion of saturated steam does not lead to the wet steam area, but stays in the superheated steam area.
In order to increase efficiency, a regenerator is usually placed between the turbine and the condenser to preheat the organic oil. This is performed using an economiser to recover waste heat from the existing boiler exhaust gas stream.
As a steam boiler is not required, investment and maintenance costs are considerably less than for steam plants. It is also highly flexible as you can choose high efficiency at partial loads (between 30% and 100%).