The truth about pollution and evaporative towers

Let’s make it clear, there’s a bad rumor about evaporative towers when speaking of environment, carbon footprint and pollution. When news on tv and newspapers talk about environment and pollution, it’s indeed very easy to see images of evaporative towers installed in industrial facilities near residential areas and roads, along with their huge plume, used as a symbol of emissions.

Well, for technicians and operators of the sector, it’s clear that these are not pollutant emissions, but simply water vapor. Cooling towers are indeed very simple machines employed for water cooling in industrial processes, using the evaporation of water to dissipate heat. Evaporative towers have very low levels of power consumption, while on the other side they consume water in direct proportion with the amount of heat to be dissipated.

The huge plume coming out of the top of cooling towers is therefore simply water vapor, droplets of evaporated water that get carried away in the atmosphere. It’s easy to understand how not-skilled people can associate it with pollution and fine dusts, but it has nothing to do with that: the plume is nothing less than water vapor, becoming even more visible during winter season, clearly due to a difference in temperature levels.

The only side effect that evaporative towers can generate is that water vapor gets condensed in the atmosphere during the coldest season, creating ice crystals. When laying on the roads nearby industrial plants, they can become dangerous for the traffic of vehicles. That’s why very often, early morning in the winter season, it’s easy to see workers charged by the industries nearby throwing salt on the streets, in order to avoid freezing and the formation of ice layers.

Evaporative towers are therefore one of the most eco-friendly machines for water cooling, and among the most efficient solutions for water cooling in industrial production processes.

Absorption chillers, free and green refrigeration power from waste heat

We gladly host a contribution from Robur, an Italian company based in the province of Bergamo, specialized in heating and cooling systems with low carbon footprint. In particular, the following article is about absorption chillers with energy recovery from high temperature waste heat in industrial processes.

Thermal energy is a very common presence in industrial production. Heat is indeed required in a number of production processes in industries such as food, industrial, textile, glass and ceramic industry, chemical, oil & gas and metallurgy.

Many among these industrial processes involve waste materials, and thermal energy is one that gets often lost at the end of the process. This is usually referred to as waste heat, and it can be present in several forms: fumes coming from furnaces combustion, or from internal combustion engines, turbine’s or cogenerators exhausts, steam coming from heat treatment plants or from drying tasks, just to name a few.

Within these same production processes, in a different step of the production line, a cooling system is then often required, also employing thermal energy but with a negative value, meaning a need for thermal cooling.

All these cases are suitable for the application of equipments that enable to employ that same waste heat to obtain chilling power, without further expenses in terms of primary energy consumes, by mean of heat recovery of the waste energy.

chiller assorbimento Robur TK

Waste heat can be divided in three classes: high energy, exceeding 650° C, mid temperature, between 225° C and 650° C, and low temperature, up to 225° C.

High and mid temperature waste heat are the most useful and ‘precious’, because they can be employed both directly or to feed further machinery such as cogenerators (combined production of heat and power) and absorbers, aimed to the production of chilling power. Low temperature waste heat can thus be employed in the form of hot air or water for heating purposes or pre-heating of further production processes that require low temperatures.

Cold production from mid-high temperature waste heat
The essential components of a machinery for cold production from waste heat are basically:

– waste heat at temperature higher than 220°C, with a proper flow rate
heat exchangers, to achieve the thermal transfer from waste heat (such as exhaust fumes of a furnace) to a thermal fluid (diathermic oil or pressurized water)
– a circulating circuit for the distribution of the thermal transfer fluid to the absorber
– an indirect fired absorber for cold production

The overall system only require additional power for the operations of accessory equipments, such as circulating pumps and fans.

Power Fluid absorber units by Robur
Robur Power Fluid absorber units are an example of efficient thermal machines that allow to ‘produce cold’ leveraging the thermal heat coming from a technological process. The working cycle of the units is showed in this scheme.

chiller assorbimento Robur

The thermodynamic cycle employs a solution of water and ammonia, in a hermetic closed circuit that avoids refill, substitution and disposal operations. The thermodynamic cycle is triggered by the waste heat flow, heating the generator by mean of a coil, in which diathermic oil or pressurized water are flowing.

Condensation happens in air, without the need of a cooling tower, thus avoiding the related hydraulic circuit and control devices.

refrigerazione recupero di calore

These units enable to produce cold water to be employed for air conditioning, production processes cooling or even for food preservation, being able to supply cold or chilled water down to -10° C.

Advantages of Power Fluid units
Each industrial process involving the presence of waste heat above 200° C and the need of chilling power can benefit from these absorber units, such as metallurgy industry, chemical, glass or cement industry, agrifood and dairy, achieving high energy savings and maximizing the efficiency of the overall production process.

Further advantages offered by Power Fluid units are:

easy engineering and installation of the plant, not requiring cooling towers and suitable for outdoor installment, with small footprint
– high reliability, thanks to an almost static refrigeration cycle (only two moving parts are employed, including fans) ensuring long life span without efficiency decrease
wide operating range, in terms of both external air (condensation) and outlet cold water, which can be supplied even at low temperatures of -10° C
– no particular permissions nor authorizations are required, since refrigerants are not employed, replaced by the use of ammonia, a totally natural and eco-friendly refrigerant (near zero ODP and GWP values)
– economically convenient, especially if the unit can be used for many hours/year, being that the chilling power obtained is actually for free

Preliminary feasibility conditions of the recovery plant
Some conditions must finally be verified for a first evaluation of the solution:

– Availability of waste heat at temperatures higher than 220-240° C. This is a mandatory condition to obtain a sufficient transfer fluid able to feed the absorber and effectively trigger the thermodynamic cycle

– concomitant presence of heat recovery and need of chilling power. The cooling energy supplied by the absorber is always subjected to the presence of waste heat to feed it. When chilling power production exceeds the cooling need it is also possible to store it, but it involves higher investments in the chiller circuit to be carefully evaluated
– Estimation of operating hours/chilling power required in order to calculate the ROI. The overall amount of chilling power produced will cover the costs of the plant, so that the higher the indicator is, the shorter will be the ROI.

Adiabatic dry cooling in steel wire drawing

We’re working on an interesting application for industrial cooling in the wire drawing process in the steel industry. In particular, the process requires cooling with water at a temperature of 25-28° C.

This is a peculiar temperature range, because this is not low enough to justify the implementation of a chiller. The application involves indeed the dissipation of several hundreds of thermal kW, and a chiller should require high costs for the machinery, first of all, and then high amounts of power absorbed, especially during the warmer season. On the other side, the temperature levels involved are too low to be satisfied using a cooling tower, especially during the warm season, even though offering very low energy consumption. In addition, being a cooling process with direct contact with the product, the water of a cooling tower has to be treated with chemicals, anti-algae, anti-bacterials and anti-limescale, thus not compatible with the product itself.

Facing this doubts, an ideal solution would be to employ a thermal machine with water in closed-loop, but we should adopt an evaporative tower combined with a heat exchanger, and furthermore we won’t obtain water at a suitable temperature.

The solution we offered employs closed-circuit adiabatic coolers, or adiabatic dry coolers. These are dry coolers with an adiabatic booster, that during the summer season employs a spray system on the air drawn into the cooler by the fans, creating a sort of ‘evaporative tower’ effect. The reference temperature is thus the wet bulb temperature, involving a low water consumption for evaporation, limited to the warmer hours of the day, in the warm season only. The system ensures to have water at the temperature of 25-28° C during the entire year, also during summer, avoiding direct contact of the water with ambient air.


Our system allows in particular very low water consumption, limited to the warmer months, not scaling nor clogging the finned coil of the exchanger. This systems ensure very high levels of efficiency, achieving cooling by using closed-circuit water with temperatures that are halfway those achieved by chiller and cooling towers.

As usual when engineering this kind of plants in Tempco, the system has been obviously equipped with an inverter on the fans. With ambient air at our latitudes, indeed, during winter and the mid-season, spring and autumn, water at the temperature of 25° C is very easy to obtain. Having fans working at their maximum speed is thus useless, and the adoption of an inverter can deliver high energy savings.

An evaluation made with the customer forecasts that the consumption of water will be limited to only two months per year, and probably only during the warmer hours. The facility also works over three shifts, and overnight the consume of water should be near zero, if not even completely avoided, also probably with a reduction of fans’ speed.

Finally, we’ve implemented a remote monitoring solution, in order to control the effective water consumption and the amount of energy absorbed by fans, looking forward to a future optimization of the overall process, in which the company is planning further investments. The gathered data also offer advantages for both of us, improving the engineering and proposal phase in Tempco, and for the customer, that can have full transparency and awareness on its thermal energy and power needs. Being also able to make an energy accounting and to evaluate the savings that can be achieved.


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Making of an effective IT Disaster recovery plan

We gladly host a contribution of Houston-based TRG Datacenters, a company that offers an innovative and customer-centric approach to datacenter management, here giving some very clear and useful tips on how to make an effective IT disaster recovery plan work.

Data centers are an important application field for Tempco, especially with TCOIL immersion heat exchangers for liquid cooling, also a crucial asset to ensure the business continuity of IT infrastructures.

An effective IT disaster recovery plan is vital for all businesses. When it comes to IT disasters, slow responses and mismanagement can quickly prove catastrophic. Data can be lost, reputations can be damaged and customers can be left very unhappy indeed. But an effective disaster recovery plan can help businesses to limit the impact of all manner of problems, guiding teams through the murky waters and straight out the other side.

Take a look at some of our top tips to ensure that your business’s IT disaster recovery plan is as good as it can be, and make sure your company is fully protected.

IT disaster recovery TRG datacenters


Regular testing and clear processes
Too many companies have a clearly defined disaster recovery plan that they hardly ever test. And when you consider some of the costs involved in full testing processes, it’s easy to see why. But testing is vital in ensuring the effectiveness of any disaster recovery plan.

Plans should be tested regularly, and in full. Because let’s face it – it’s quite likely that every single aspect of your recovery plan won’t go exactly as you had imagined. Thorough testing will enable you to iron out any little hiccoughs at your own pace, and double check every detail of your plan. Do this and you’ll avoid potentially stressful, time-critical challenges if you ever do need to employ the plan in a real-life situation.


Awareness of the human factor
It’s a slightly awkward fact that a whopping 70% of IT outages aren’t actually caused by problems in infrastructure design. They’re the result of human error.
Errors can be caused by many different factors, ranging from insufficient training to poor management decisions. There’s no failsafe way to protect your systems from human error, but there are ways to minimise the risks.
We always recommend that the vast majority (at least 70%) of your disaster recovery planning efforts focus on the humans that power your business. Invest time and energy in the human aspect of your strategies, and you’ll start to limit the associated risks.


A well defined set of objectives
Before you can create the ideal disaster recovery plan, you need to know what constitutes a disaster in the eyes of your business. Decide on what a disaster, and subsequent recovery would really mean, and how you might measure the success of your plan.
As a starting point, consider the amount of uptime your business requires, what you mean when you say that systems are ‘working’, and what your teams would call a success in terms of disaster recovery.


A role in day to day management of operating responsibilities
Disaster recovery planning should never be a task that’s done once and quickly forgotten about. For plans to be truly effective, they must be discussed and updated regularly.
It’s a good idea to incorporate disaster recovery into the day to day management of operating responsibilities, and make sure all team members are on board with what the plan entails, and how to use it. Disaster recovery strategies must become part of normal operations for IT teams, if they are ever to fulfil their real potential.


Few things are as important as disaster recovery planning, particularly when you consider the impact that inadequate plans and processes can have on a company. Take the time to make sure your systems are protected from the wide range of risks out there. Think carefully about what disaster planning means to your business, and you’ll be able to effectively prevent the hugely damaging impact of insufficient planning.

Tempco, testing on enlarged energy saving

Going on with the enviromental theme, I would like to talk about something new and a little unusual, not exactly focused on heat exchangers, cooling towers and thermoregulating units. Or to say it better, these are all involved, but from a different perspective. The energy saving is something the whole industrial world is increasingly looking at, and when in Tempco we are asked to evaluate a solution for temperature regulation in some industrial process, the very first thing we are requested to is which kind of energy saving levels can be achieved, by implementing technologies and solutions for energy efficiency along the temperature regulation in the production process involved.

Some example are the employ of inverters on engine fans, saving energy when a lower power capacity is required for ventilation, for instance on dry coolers, cooling towers and free coolers. But also the use of tiristors on heating resistances, when engineering a thermoregulating unit with electrical heating section, enabling the adjustment of the power absorbed supplying a lower power capacity in kilowatt needed in a certain moment. Finally, the use of inverters on circulating pumps, as we are actually installing on a very interesting application for a customer in the metallurgical sector in the northern province of Milan, where we are implementing a saving and energy efficiency system for the pumps working in the cooling circuit.

But even more interesting would be the possibility to extend the use and the advantaged of these solutions in the civil sector also, for everyone’s benefit, and not only for the industry. In fact, I’ve been recently in contact with many companies, and one in particular, highly committed in the research of energy saving applications in non-industrial fields, thus regarding applications in the civil sector such as with conditioning, heat pumps and geothermal heat pumps. Discussing these opportunities really gave me thrills, moreover in the past Tempco has already developed applications with TCOIL dimple jacket immersion heat exchangers for the energy and heat recovery from sea water, feeding the condensing water of heat pumps. A similar application was also installed on the Lake of Como, and another one in Ispra, on heat pumps leveraging the water of a turbine drain.



Well, this being said, this company asked us to do some tests for energy recovery with our TCOIL immersion heat exchangers, from heat waste coming from domestic hot water and other services. An application surely worth a more in depth study. The main problem here are the costs of investments that can rise up, with a return of investment quite in the long term period. But I really feel and think it is truly worth it here to invest a bit more, even with a long-term ROI and thus a different pay back compared to the very short-term pay backs usually required for industrial investment plans.

I’m therefore very convinced that it is worth it to study what it can be achieved and done in these new sectors, and that’s why in Tempco we have ensured our full availability to make tests and attempts, hoping we will be soon able to meet in person – not really easy in this period of public health emergency due to the cover-19 outbreak we’re all living – and proving this systems, collaborating to contribute in our own small way to the health of the planet.

A new effort that joins what we are already doing in Tempco for the environment, as we’ve already talked about it, such as the use of 100% renewable energy and the dematerialization of our paper archives. These are themes that I would love to discuss with you all, and looking forward for your comments and suggestions here below. Maybe a webinar or a Skype call would be also interesting to plan, to find out what are the latest trends and best practices in energy saving solutions for the next years.

Environment and health and safety policy in Tempco

We don’t talk about that very often, but environment and health and safety policies are very much important in Tempco, as we operate in total compliance with Italian regulations in this fields.
Our collaborators’ safety is at the very top place above everything else, and not only in reference to the particular and exceptional times we are currently living because of covid-19 emergency.

We’ve suddenly ensured to be compliant with the requirements of the DVR (Italian risks assessment document) as soon as it was released, on topics regarding health and safety at work (D.Lgs. 81/2018 and following integrations introduced with D.Lgs. 106/2009 in Italian legislation).

Now more than ever important, the DVR also includes a section regarding the risks related to biological agents exposure, which has been properly upgraded with all the measures adopted in order to ensure the maximum protection to our collaborators against coronavirus.

Maximum attention is then also due to the protection of data of our customers, suppliers and collaborators. We are moreover compliant with tax regulations.

Tempco ambiente sicurezza


On the environmental side, Tempco embraced since its beginnings all the technologies and green solutions available to lower the impact of our activities, getting continuously updated to effective laws.
Since the very first project of the new building hosting our activities, we pursued the goal to reduce as much as possible our carbon footprint. A photovoltaic plant has been installed and is operating since the start of 2011, in order to employ only renewable energy. For the additional power supply required, we chose an energy provider, Duferco, that is able to guarantee at 100% the origin from renewable sources of the energy supplied.

The company is also a Tempco customer, so that the choice was made aiming to minimizing the environmental impact, likewise to a near ‘Zero food miles’ supply chain approach.

Tempco energie rinnovabili


At last, but not least, we put maximum attention on recovery and reuse of materials. We carefully select our partners and suppliers following parameters based not only on quality, but also upon the provenance of materials and the ethics and social responsibility policies of their production activities.
On packaging materials, Tempco adopts an active annual campaign for the recovery of wood/cardboard/plastics. Each month we supply exhaust boxes to companies that reuse them for promotional and exhibition purposes and/or in the agricultural sector.

We would also like to recall here the example of our collaboration with Besana Farm, that employs the shredded paper coming from the dematerialization of our archives for the care and well-being of their horses.



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Oil viscosity grade in plate heat exchangers design

Plate heat exchangers, but shell and tube exchangers as well, are widely employed in oil cooling for hydraulic units and plants. A main factor to consider in this kind of applications is the viscosity grade of the oil, a crucial element in the sizing process of the heat exchanger. For engine oils, the viscosity is usually expressed in SAE grades, while hydraulic oils use ISO-VG classification, indicating the oil viscosity grade.

Higher viscosity grade oils involve higher pressure drops inside the exchanger, which must be considered during the design of the heat exchanger, in order to avoid problems with the pump that ensures oil circulation within the exchanger.

When working with high viscosity grade oils, for instance ISO-VG 320 or ISO-VG 220, typically lubricating oils, it is mandatory to use gear pumps, thus with high pressures, that allow higher pressure drops inside the exchangers, even up to 1,5 bar or 2,5 bar.


In case of lower viscosity grade oils, typically employed in drive hydraulic plants, with viscosity grade such as ISO-VG 46 or ISO-VG 68, pressure drops can be even lower, in the measure of 1 or 1,5 bar, because the oil is less viscous and therefore smoother, leading to lower pressure drops inside the heat exchanger.

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Covid-19, even a heat exchanger makes a difference

The global Covid-19 health emergency requires a collective commitment that embraces all the companies directly involved in the production of individual protective devices and protective masks, respirators and medical equipment aimed to intensive care units, drugs and pharma products and all the services supporting the healthcare sector.

Many Italian enterprises are offering their support in this period, giving their innovation capacity and flexibility to help hospitals in severe difficulty due to the coronavirus outbreak.

coronavirus pharma covid-19


Recent industrial reconversions and the readiness and creativity of entrepreneurs gave many great examples. Starting with Tenaris from Dalmine, near Bergamo, that supplied in record lead times a lot of tanks for the oxygen produced by Siad, but also the automotive world with Ferrari and FCA together with Magneti Marelli, ready to convert their production lines to increase the availability of ventilation machinery, supporting the activities of Siare Engineering, the leading Italian supplier of these essential medical equipments in intensive care units. The Armani Group has also announced that it will immediately start to produce medical protective disposable white coats for all the hospitals and the healthcare operators fighting the coronavirus from the front row.

Another brilliant example is the Isinnova Italian startup, that under urgency designed a special Venturi valve, printed in additive manufacturing, to connect respiratory masks to ventilators at the Chiari hospital, in Brescia. The same company then adapted a commercial snorkeling mask, by the sport gear and equipment specialist Decathlon, turning it into a respiratory mask for sub-intensive therapy, thanks to a special patented junction valve.

Tempco designs and realizes plants serving many industries that are often directly involved in the production of materials and products in the chemical, medical and pharmaceutical industry. The status of emergency put the production facilities under an intensive workload, so that equipment’s availability is becoming even more important and strategic when compared to usual market demand conditions. The best efficiency is also granted thanks so more frequent monitoring on all the industrial production processes, especially on heat exchangers, which are at the core of thermal energy control tasks.

Tempco scambiatore API covid-19


The images in this article are showing a plate heat exchanger with clear wear and corrosion signs, following years of working service, fouling on equipments and damaged gaskets. This is not a common heat exchanger: the plate heat exchanger pictured above is indeed installed in the facility of a customer in the pharma sector and employed in the production of an API, i. e. an active pharmaceutical ingredient, actually employed to treat Covid-19.
Last week the customer contacted us under extreme emergency, asking for our intervention for the substitution of the plate pack or the supply of a new equivalent heat exchanger, everything that was feasible but in the shorter time possible.

scambiatore di calore API covid-19


The customer is one of the many companies, part of the healthcare industry supply chain but not only, which are actually dedicating all of their resources and know-how to contrast the outbreak of the coronavirus disease in Italy.

Understanding the delicate emergency situation of our customer, that needed the exchanger fixed, ready and delivered as sooner as possible, a day of heavy work started in Tempco, after having retrieved all the necessary materials around Italy, with a considerable logistic effort.

On Friday morning the plate heat exchanger was finally ready for delivery.

scambiatori a piastre pharma covid-19


We’ve been glad to be able to make our own tiny part too, and this clearly shows how everyone is deeply concerned in the solidarity chain triggered by the health crisis, and that economy is grounded on the tight collaboration among all the companies, big and small enterprises, and professionals.

To all the actors that during these times are making their best to contribute in this public health emergency, ensuring at the same time the best safety measures to all their workers, a huge applause and thanks, because working together all the industries can make a difference, as they’re already doing it.

Tempco scambiatori calore API covid19

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How to properly install multi-pass plate heat exchangers

This week, let’s talk about mono pass and multi pass plate heat exchangers. Despite we’re used to see images of heat exchangers with the traditional four attachments on a single side, the front, there are also exchangers with attachments of two sides, both the front and the rear. These multi-pass heat exchangers have inside usually a particular scheme of the plates, called multi-pass design which involves a multi-pass flow control.

This multi-step diagram is employed in case we need very long thermal lenghts and very high temperature crossings, usually required in heat recovery applications. This sort of a ‘trick’ allows to stretch the plates, obtaining a thermal length of the plates a lot higher, in fact twice high compared to the height of the exchanger. This solution allows to push the recovery, that is the intersection of temperatures, up to very high limits.


On the other side, this solution brings some inconvenience, such as the pressure drops that will tend to increase. But it’s also true that those can be managed while designing the exchanger, by inserting them into the engineering software in order to compensate pressure drops by increasing the number of plates, i.e. the number of channels in parallel.

Another possible issue in case of a multi pass exchanger installation is the fact that it has connections on both the front and the rear, and it can bring some inconvenience. Having valves directly mounted on the rear side of the exchanger, when doing maintenance of the heat exchanger the pipes will make it difficult to access the rear stem to dismantle the plates, washing them, replacing the gaskets and so on. That’s why in case of multi-pass heat exchangers is suitable to install 90° curves on the rear connections, moving the valves outside the shape of the exchanger, so that during maintenance valves can be intercepted and the curves can easily be disassembled, gaining easy access to the rear stem.

One last issue that occurs with multi-pass exchangers is the fact that they cannot be boosted and upgraded without connection pipes adjustments.

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Atex thermoregulation for resins and chemical products

Pictured here are ATEX thermoregulating skid units of reactors employed in the production of resins and other chemical products. This particular application saw maximum satisfaction of our customer, a company operating in the chemical sector, involved in the production of special adhesives largely employed in food industry packaging and the automotive industry.

Tempco termoregolazione Atex chimica


The customer previously used to employ a solution with direct jacket injection of steam and cold water. The implementation of our thermoregulating units solution gave excellent results, so that the company presented the case study with our skid units as a best practice to both the Group in the USA and the European affiliated companies.

Termoregolazione skid Atex

Tempco termoregolazione resine

Tempco centraline Atex chimica

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