flue gas heat exchanger

A flue gas heat exchanger is a preheating system used, for example, in boilers where exhaust gases are used to increase the temperature of the incoming air stream by reducing the thermal difference. Thus, the same boiler can achieve the same result using less energy.

In these recovery systems we can find different systems, such as air-air, air-gas or air-exhaust fumes systems, and also using other methods, such as air-water or air-steam systems. For example, in wood dryers.

These systems are important to take advantage of all our industrial resources and use surplus industrial energy to reduce our consumption and be more responsible for the environment.

At Boixac Tech we have air-to-air exchangers that can work with high temperatures, high pressures, dusty and corrosive environments.

Economizer for greenhouses

February 10, 2025February 10, 2025 by Oficina Tècnica

ECONOMIZER FOR GREENHOUSES GREENHOUSES AND FARMS An economizer for greenhouses or farms refers to the heat recovery system designed to improve efficiency in an environment where, among other things, crop performance is optimized by controlling temperature, ambient humidity, and CO₂. Within the wide range of implementations, we highlight three main areas: 1. The first block refers to water treatment for the hydroponic growth of tomatoes, lettuces, peppers, strawberries, etc. Hydroponic cultivation allows plants to grow faster and more vigorously thanks to direct access to nutrients. These nutrients are dissolved in a water flow that is distributed to the plants through channels. For proper nutrient absorption, it is important to maintain the water within certain temperature ranges, which is achieved thanks to our finned tubes. This heat exchange system can use spiral fins or continuous fins following the same direction as the tubes, maintaining a homogeneous temperature and optimizing both plant growth and quality. 2. The second block is air treatment through overhead ducts, where BOIXAC provides the finned heat exchangers that condition the air in the greenhouse or breeding farm. These exchangers can include various accessories such as fans, humidity controls, and temperature controls. 3. The third block refers to the technology that enriches the environment, thus increasing photosynthetic activity. We achieve this by reusing the excess energy from exhaust gases through the ECO, AIRY, or GASY heat recovery systems. These thermal exchange units are selected based on primary and secondary fluids; in addition, the materials are also chosen according to the specific needs of each installation. Custom solutions for energy optimization in greenhouses and farms. Heat recovery systems for greenhouses and farms Water coil Water coil that is often used to condition the environment of greenhouses and breeding farms, improving animal welfare. Energy economizer Energy economizer or heat recovery system that allows the reuse of excess energy, for example, from biomass boilers. Finned heat exchanger Finned tube heat exchanger, a temperature control system that optimizes durability even in environments with certain contamination factors.

Heat exchanger

February 10, 2025September 29, 2023 by Oficina Tècnica

HEAT EXCHANGER QUESTIONS AND ANSWERS The heat exchanger answers provided below are strictly for guidance and should not be considered as definitive technical advice. To ensure correct and safe application, it is essential to contact our technical office, where qualified professionals will advise you based on your specific needs. BOIXAC assumes no responsibility for any misuse or misinterpretation of the information provided here. Always prioritize safety and rely on specialists for any tasks related to our products. What is a heat exchanger? A heat exchanger is a device whose function is to transfer thermal energy from one element to another, cooling and heating. These elements can be gases, liquids or solids and, depending on their characteristics, with the aim of optimizing efficiency in the heat transfer process, the construction of the heat exchangers can vary. What is a heat exchanger for? A heat exchanger facilitates the transfer of thermal energy, cooling and heating different elements among which we can find fluids, gases and solids. This function is especially useful in industrial processes such as drying, pasteurization, evaporation, refrigeration or distillation. Likewise, it also serves to recover residual energy, control ambient temperature and cool engines. What industries use heat exchangers? The thermal treatment of heat exchangers is essential for many of the processes in the energy, food, chemical, sugar, glass, automotive, paper, pharmaceutical, materials drying, textile, oil, gas, metallurgy, data centers and electronics industries. We also find heat exchangers in other areas such as agri-food and tertiary. How does a heat exchanger work? A heat exchanger is characterized by having two sections, in each of which an element circulates that can be fluid, gas or solid. These sections are separated by the thickness of a tube or plate through which heat is transferred from one side to the other without the flows mixing. For thermal energy to be transferred there must be a certain temperature differential between the flows and the selected materials must be conductive. This is why heat exchangers are often made of copper, aluminum, steel, stainless steel, titanium or cupro-nickel, both to maximize the heat exchange coefficient and also to adapt to the different particularities that each element may have. The selection of heat exchanger construction is directly related to the working conditions. What types of heat exchangers are there? Heat exchangers can be manufactured following very different constructions, among which we highlight: 1. Tube exchangers. Heat exchanger with smooth tubes, without fins. Heat exchanger with tubes and continuous fins. Heat exchanger with tubes and helicoidal or spiral fins. 2. Plate exchangers. Pillow plate heat exchangers. Cross flow plate heat exchangers. Removable plate heat exchangers. Welded plate heat exchangers. 3. Multitubular exchangers. Double tube heat exchangers or concentric tubes heat exchangers. Tube and shell heat exchangers. What is the efficiency of a heat recovery unit? A heat exchanger is a passive device, meaning that it does not generate heat or cold by itself. The same design can offer different levels of efficiency depending on the conditions with which we make it work. Among the working conditions we find concepts such as the typology of fluids, flow rates, temperatures, absolute humidity or fouling factors. Once the user has defined the objective, for example, reaching a certain power or a certain temperature at the fluid outlet, the technical office has the objective of finding the construction that optimizes the efficiency of the heat exchanger. Where can we buy a heat recovery unit? Since each facility has its own singularities, in order to optimize the efficiency of each installation, heat exchangers must be custom designed and manufactured. This is why we recommend contacting a specialist who will guide you in the selection and acquisition of these devices. We encourage you to visit our website and contact us, our technical office highly specialized in heat exchangers will guide you. How can I choose the right equipment? To choose the right heat exchanger, it is essential to consider several factors, including the inlet and outlet temperatures of the fluids, the flow rates of the fluids involved, the type of fluids and their characteristics (viscosity, corrosiveness, fouling, etc.), access, space, and installation constraints, as well as maintenance and durability requirements, among others. Its complexity requires contacting a specialist like the experts at BOIXAC to guide you and ensure the design is properly tailored to your needs. What maintenance does a heat exchanger require? Regular maintenance is crucial to ensure optimal performance. The most common steps are: periodic cleaning to remove fouling and deposits that reduce efficiency, inspections of gaskets and components to detect possible wear or damage, especially in critical parts, replacement of worn parts to avoid operational failures, and pressure tests to ensure there are no leaks or structural weakening. The maintenance frequency will depend on the process conditions and usage. What is fouling, and how does it affect performance? Fouling refers to solid deposits that accumulate on the surfaces of the heat exchanger due to sediments, minerals, or other particles present in the fluids. This phenomenon can reduce heat transfer, increase energy consumption, and/or cause premature wear of the system. Prevention through filters and regular cleaning is essential to minimize these effects. How can I detect and prevent leaks in a heat exchanger? Leaks can be caused by worn gaskets, corrosion, or mechanical damage. To prevent them, it is advisable to perform regular visual inspections, implement pressure or temperature sensors to detect anomalies, and use corrosion-resistant materials in systems handling aggressive fluids. If in doubt, always contact our technical team. What are the signs of heat exchanger malfunction? The most common indicators of malfunction are: a drop in thermal efficiency (fluids not reaching the desired temperature), increased pressure loss, visible fluid leaks, strange noises, or vibrations during operation. If in doubt, consult a qualified technician. Can a heat exchanger be customized? Yes! We offer customization options to meet specific needs, such as special materials, unique dimensions, or configurations for unusual fluids. A tailor-made heat exchanger ensures the best results under specific … Read more

Heat exchangers in the energy industry

February 4, 2025February 1, 2023 by Oficina Tècnica

ENERGY INDUSTRY HEAT EXCHANGERS FOR ENERGY OPTIMIZATION Heat exchangers are a very important product in the optimization of energy transformation processes, whether in thermal power plants, nuclear power plants or hydroelectric power plants, among others. Let’s dive deeper into the uniqueness of each of these systems below: 1. In thermal power plants, heat exchangers are used to transfer heat generated by fossil fuels such as coal, oil or gas to a fluid such as superheated water or steam. This fluid reaches high pressures and drives a turbine that generates electricity. As the fluid drives the turbine, it cools and we condense it using a new heat exchanger we call a condenser. Once condensed, we reuse the fluid to heat it with fossil combustion and generate energy again. In thermal power plants we could find cogeneration plants which, in addition to producing heat, generate electricity, as well as trigeneration plants, which, in addition to producing heat and electricity, generate refrigeration energy, which means greater energy efficiency and sustainability. 2. In nuclear power plants, heat exchangers are essential to control the temperature of the reactor with the help of a coolant. The heat transfer fluid absorbs the heat and transmits it to a steam generator which will convert the energy into electricity. This coolant, once cooled, will return to the start to start the process over. Beyond this aspect of operation, heat exchangers are also used as a preventive measure in diesel engines with the aim of controlling a possible electrical shutdown. There are many other models of energy generation, all with very particular singularities that we will analyze in other articles. Beyond the explanatory brushstrokes we have made, all projects require in-depth analysis and a highly experienced professional team. If you have any needs, contact us, we are at your disposal. Heat recovery for the energy industry Gas heat recovery Heat recuperator that economizes with the use of exhaust gases from boilers, turbines or combustion engines used for example in cogeneration. More efficiency and less emissions. Counter flow heat exchanger Cross-flow heat exchanger, usually between a stream of fumes or gases and another of air, without them mixing. With a design that is easy to clean and maintain. It is ideal for the energy, oil and gas sector. Steam heat exchanger Coil of tubes designed to convert saturated or wet steam into dry, superheated steam, usually by steam turbines for electricity generation. They can withstand temperatures of up to 950ºC.

Industrial economizer

February 4, 2025June 1, 2022 by Oficina Tècnica

ECONOMIZER GREENHOUSES AND FARMS An industrial economizer or heat recovery system helps improve efficiency in many different areas, one of which is greenhouses, where, among other things, it optimizes crop performance by controlling temperature, humidity, and CO2 levels. Within the wide range of implementations, we highlight three main blocks: 1. The first block refers to water treatment for the hydroponic growth of tomatoes, lettuces, peppers, strawberries, etc. Hydroponic cultivation allows plants to grow faster and more vigorously thanks to direct access to nutrients. These nutrients are dissolved in a water flow that is distributed to the plants through channels. For proper nutrient absorption, it is important to maintain the water within certain temperature ranges, which is achieved thanks to our finned tubes. This heat exchange system can use spiral fins or continuous fins following the same direction as the tubes, maintaining a homogeneous temperature and optimizing both plant growth and quality. 2. The second block is air treatment through overhead ducts, where BOIXAC provides the finned heat exchangers that condition the air in the greenhouse or breeding farm. These exchangers can include various accessories such as fans, humidity controls, and temperature controls. 3. The third block refers to the technology that enriches the environment, thus increasing photosynthetic activity. We achieve this by reusing the excess energy from exhaust gases through the ECO, AIRY, or GASY heat recovery systems. These thermal exchange units are selected based on primary and secondary fluids; in addition, the materials are also chosen according to the specific needs of each installation. Custom solutions for energy optimization in greenhouses and farms. Heat recovery systems for greenhouses and farms Water coil Water coil that is often used to condition the environment of greenhouses and breeding farms, improving animal welfare. Energy economizer Energy economizer or heat recovery system that allows the reuse of excess energy, for example, from biomass boilers. Finned heat exchanger Finned tube heat exchanger, a temperature control system that optimizes durability even in environments with certain contamination factors.