Combined heat and power (chp) system

Abstract

Combined Heat and Power (CHP) system, comprising an engine or turbine, a generator and a heat exchanger, wherein the heat exchanger has at least one flue duct in fluid communication with an exhaust of the engine or turbine and at least one fluid duct, the heat exchanger arranged for exchange of heat between flue gasses flowing through the at least one flue duct and a fluid flowing through said at least one fluid duct, wherein the at least one flue duct is formed by at least extrusion.

1 . Combined Heat and Power (CHP) system, comprising an engine or turbine, a generator and a heat exchanger, wherein the heat exchanger has at least one flue duct in fluid communication with an exhaust of the engine or turbine and at least one fluid duct, the heat exchanger arranged for exchange of heat between flue gasses flowing through the at least one flue duct and a fluid flowing through said at least one fluid duct, wherein the at least one flue duct is formed by at least extrusion. 
     
     
         2 . CHP system according to  claim 1 , wherein the heat exchanger is made using extrusion technology and wherein at least the flue duct or ducts and the water duct or ducts are made in light metal, especially aluminium or an aluminium blend. 
     
     
         3 . CHP system according to  claim 1 , wherein the flue duct is defined by flue duct defining walls which have a surface roughness of less than about 25 Ra, preferably less than 12.5 Ra, more preferably less than 6 Ra, even more preferably less than 2 Ra. 
     
     
         4 . CHP system according to  claim 3 , wherein the roughness is less than 1 Ra, preferably about 0.8 Ra or less. 
     
     
         5 . CHP system according to  claim 1 , wherein the at least one flue duct has flue duct defining walls which are, seen in a flow direction of the duct, free of obstructions such as heat exchanging surface increasing elements. 
     
     
         6 . CHP system according to  claim 1 , wherein the at least one flue duct comprises a series of parallel duct sections, fluidly connected to each other for forming a zig-zag flue path, wherein each of the sections, seen in a flow direction of gas through the relevant section, is free of obstructions such as heat exchanging surface increasing elements. 
     
     
         7 . CHP system according to  claim 1 , wherein the at least one flue duct is straight or has parallel sections which are straight, wherein a flow direction of gas through said at least one flue duct or said parallel sections thereof is parallel to a extrusion direction of said duct or duct section. 
     
     
         8 . CHP system according to  claim 1 , wherein the heat exchanger is provided with at least one closable opening into said at least one flue duct, for cleaning of the flue duct. 
     
     
         9 . CHP system according to  claim 1 , wherein the heat exchanger comprises a body made by extrusion, including said at least one flue duct and said at least one fluid duct, and wherein opposite ends of the body are closed by end elements, which are preferably glued to the body. 
     
     
         10 . CHP system according to  claim 1 , wherein the heat exchanger comprises at least two parts made at least partly by extrusion from light metal or light metal alloy, said at least two parts mutually engaging for forming part of a heat exchanging space formed by or comprising said at least one flue duct and/or a water conducting channel formed by or comprising said at least one fluid duct, wherein each of said at least two parts comprises part of said heat exchanging space and/or said water conducting channel, wherein said at least two parts are connected by an elastic bonding agent, in particular an elastic glue, forming a bond and a seal. 
     
     
         11 . CHP system according to  claim 1 , wherein the CHP further comprises a cooling circuit for the engine or turbine, which circuit includes a second heat exchanger, which has a fluid duct connected in or to a fluid circuit including the at least one fluid duct of the first heat exchanger, such that during use heat can be transferred from the cooling fluid of the engine to the fluid flowing through the circuit including the said fluid duct of the first heat exchanger. 
     
     
         12 . CHP system according to  claim 1 , wherein the at least one flue duct or parallel sections of the flue duct(s) has/have straight duct forming walls and substantially rectangular cross sections perpendicular to a direction of flow through said duct or section. 
     
     
         13 . CHP system according to  claim 1 , wherein the flue duct or parallel sections of the flue duct extend in a direction of extrusion of the heat exchanger, and are free from flow obstructions and heat exchanging surface increasing elements extending into the duct or section as such obstruction. 
     
     
         14 . CHP system according to  claim 1 , wherein the heat exchanger is positioned such that the flow of flue gas through the heat exchanger is substantially horizontally. 
     
     
         15 . CHP system according to  claim 1 , wherein the system further comprises at least one of:
 at least one and preferably at least two containers for holding water heated by the said heat exchanger or heat exchangers;   at least one heating circuit for special heating;   at least one additional heating boiler for heating fluid, especially water; and   a controller for at least the engine or turbine, the generator and a pump in a fluid circuit connected to the at least one fluid duct.