exhaust gas exchanger

An exhaust gas exchanger, is a preheating systems used, for instance, in boilers where exhaust fumes are used to increase the temperature of the inlet air flow reducing the thermal difference. So the same boiler can achieve the same result by using less energy.

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

These systems are important to take advantage of all our industrial resources and use the exceding industrial energy to reduce our consumption and being more responsible with the natural environment.

At Boixac Tech we have exhaust gas heat exchangers that can work with high temperatures, high pressures, dusty and corrosive environments.

Heat exchanger

December 15, 2023September 29, 2023 by Oficina Tècnica

HEAT EXCHANGER QUESTIONS AND ANSWERS 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 exchanger? 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 exchanger? 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.

Industrial economizer

July 10, 2023June 1, 2022 by Oficina Tècnica

ECONOMIZER GREENHOUSES AND FARMS Heat recuperators are important in many fields and one of them are greenhouses and farms. In this area we work in two main blocks: 1. The first block refers to the treatment of water for the hydroponic growth of tomatoes, lettuce, peppers, strawberries, etc. One solution is to heat the water in the channel before it is distributed to the plants through finned tubes. These heat exchange systems can be supplied with spiral fins or continuous fins in the same direction as the tubes. This technology homogenizes the heat in all plants and facilitates its control. Another solution is heating the air through upper ducts where BOIXAC provides the finned exchangers that heat the air in the greenhouses and farms. These exchangers can include multiple accessories such as fans and controls. 2. The second block refers to the technology that enriches the environment and thus increase photosynthetic activity. We do this by reusing the excess heat from the exhaust gases through the ECOND, AIRY or GASY heat recuperators. These heat exchange equipment are selected based on the primary and secondary fluids, in addition, the materials are also chosen according to the specific needs of each installation. Customized solutions for greenhouses and farms optimization.

Industrial heat recovery

July 10, 2023June 1, 2021 by Oficina Tècnica

INDUSTRIAL HEAT RECOVERY THE GREENEST, OPTIMAL AND SUSTAINABLE ENERGY BOIXAC had the honor of being invited and participate in the podcast Con G de Geo, which aims to bring engineering closer analyzing concepts such as sustainability, through renewable energies, energy optimization and the efficient use of our resources. You can read the trasncription of our contribution below and we encourage you to listen to us through the following link. “In December 2019, the European Green Deal was approved, which aims to achieve climate neutrality by 2050. To do this, a scale was made with the different actions to be carried out and, one of the steps on which we will stop and we will analyze if we have done our job is in 2030. In addition to aspects such as recovering biodiversity, improving animal welfare or promoting sustainable forest management, there are three aspects that directly influence the field of energy: – Establish a minimum share of renewable energies of 40%. – Improve energy efficiency by 36-39%. – Reduce greenhouse gas emissions by 55%. All these aspects are important to find a solution to the climate emergency but, at BOIXAC, we understand that if the world population continues to increase, for example, only in Spain an increase of 2% in the next 15 years is prevented, beyond the use of renewable energies, sustainability goes through the change in consumption habits and the optimization of our resources. In this sense, considering that the Spanish industry consumes about 31% of total energy, its modernization and optimization is one of the keys to our future. When we go along the highway, as far as the eye can see, we see factories that need energy for their processes, for instance to heat wastewater and facilitate the biological digestion of sludge, dry cement for its correct conservation, increase CO2 in greenhouses to increase the rate of photosynthesis, cool foods such as chocolate for modeling, etc. All processes that need to heat or cool require energy, and energy maintains a balance. In fact, heat is the transfer of energy from an area of high temperature to another area of lower temperature. If, for example, we look at what happens in our homes when we turn on the air conditioning, we will see this balance. While the indoor unit blows out cool air, the outdoor unit blows out excess heat. Starting from this energy balance, we see that a certain renewal of the indoor air is needed to maintain its quality. For this renewal we take the outside air and cool or heat it depending on each need. At the same time that we introduce the new air, we must expel the excess air from the interior so that the new one can fit and this is where we come in with heat recovery. If we make a leap from our homes to the industry and imagine, for example, that the outside air is at 20ºC and we want to heat it so that it reaches 80ºC inside, for example, in a dryer where we need to extract moisture . Here we apparently need equipment that is capable of increasing the air temperature by 60ºC, from 20 to 80ºC. However, there is another option that is smarter, cheaper and more sustainable. When we take this air from the outside at 20ºC and we want to heat it to introduce it into a room, the same flow of air that was inside at 80ºC will be expelled. By means of a heat recovery system we make these two air flows cross each other without mixing through a system known as cross flows. We do not mix these flows in order to maintain the quality of the previously filtered air, but we do extract the heat from the outgoing air flow and transfer it to the incoming air flow. With this system we achieve two objectives; 1. The cold air that we are introducing will rise in temperature, so that the equipment we use to heat it, often boilers, will be able to work more relaxed, consuming less energy and, therefore, saving and being more sustainable. 2. The hot air that we are expelling will significantly lower its temperature, resembling the ambient temperature and, therefore, we will be even more sustainable. The technology of heat recovery units may change depending on the application and the manufacturer, but, as we have seen, it is based on perfecting the filters to offer correct air quality, and the fans to obtain air circulation. the lower electricity consumption and the energy recuperators that are the heart that allow the magic of heat exchange. Here you can add other added values such as control or isolation. In our particular case, from BOIXAC, we specialize in industrial heat exchangers and, just as it is important to work to improve ventilation and filtering techniques, exchangers also progress to offer solutions resistant to corrosive environments, high pressures and temperatures. up to 950ºC, with flattened tubes to reduce pressure losses and compact constructions that currently reach efficiency levels of over 80%. In the industrial field, applications have many singularities such as fluids, viscosities, pressures, temperatures, materials, fouling coefficients, etc. That is why each project is studied in detail to optimize its construction and thus achieve the objectives of energy efficiency, sustainability and savings necessary for industrial progress.”