The Need for Hot Oil Filtration

Hot oil filtration is a necessity. Thermal cracking and oxidation lead to the degradation of heated oil which results in the collection of sludge and coke. These substances which collect in pump seals and internals, values, etc., cause equipment problems and eventually break down the system. Continuous contaminant, if kept uncontrolled without hot oil filtration, can affect the heating surfaces of your system and thus reduce heat transfer efficiency. There is also a cost factor involved with rapid hot oil breakdown.  Hot oil has to be replaced more frequently. Seals, valves, rotors and mag-drive canisters get affected and have to be replaced. Increased maintenance and repair time which would mean higher labor working hours.

Increasing the fluid life with an in-line filtration system

Many system problems cause the oil to degrade prematurely.  By installing a side stream or an in-line filtration system, you can increase the fluid life. In-line filters should be used only with positive displacement pumps (gear) not a centrifugal pump. In critical applications such as high-temperature electric systems, a second filter in parallel duplex can be installed. Side stream configuration is recommended for systems with centrifugal pumps. The optimal flow rate through a side stream filter is 10% of full system flow. Minimum recommended flow rate is 3%.

Typical filters embody a canister, which is a metal housing with a fiberglass element labeled as filter or cartridge. Cartridges come in sizes ranging from 5 to 100 microns. For more severely contaminated hot oil systems you can start with a 100-micron cartridge and over time work down to a 5 to 10-micron cartridge.

The inlet of the filter is installed close to the discharge side of the pump. The heat transfer fluid is then diverted to the filter by drawing off the existing pipe, for maximum performance of 10% of the stream. The fluid is cleaned through the filter and then piped back in downstream or to the suction side of the existing pump. Positive shut-off ball valves should be installed on both sides of the filter to allow for cleaning without shutting down the entire system.

Advantages of Filtration

• Filtration removes particulates that can vitiate the oil
• Viscosity of fluid is maintained longer by reducing sludge build-up
• The thermal efficiency of the system lasts longer and you can save on energy costs.
• Prolongs oil life
• Reduced maintenance costs by protecting pumps and valves from contaminates

Many reputed companies provide filtration systems that are incredibly effective for cleaning and maintaining the efficiency of heat transfer fluids, thermal or hot oils. Built for in-system filtration their patented filter housings use proprietary filter elements to enhance optimum cleaning of the oil at elevated temperatures since they can withstand system temperatures of up to 750°F (399°C). The filter elements have an excellent dirt-holding capacity, are economical and disposable. The Sentinel series offers a complete stand-alone system that will re-circulate a portion of the fluid through the filter unit and discharge the clean fluid downstream into the main piping at a pressure higher than the system.

An Effective Industrial Equipment for the Industry

Saving energy is a costly problem for business enterprises and the primary reason for choosing devices that helps to save as much heat as possible. Heat exchangers are often used for this purpose. So what exactly are heat exchanger systems and how do they work for transferring the heat?

Put simply; a heat exchanger helps to transfer heat from a liquid or gas from one medium to another without directly contacting the fluids.It helps to pass the heat from the warmer fluid to the colder fluid, with both streaming the flow with the aid of the pipe network.

What are heat exchangers used for?
Heat exchangers are commonly used in all kinds of places, such as a refrigerator or air-conditioners. As these machines usually work to heat or cool, they need an efficient medium to work more capably. However, their primary use is in complex machines in industrial factories that require sophisticated heat exchangers to manage the enormous amount of heat that is produced every day.

In power plants or industrial machines, exhaust gases often contain a high amount of heat that is unnecessarily released into the open air. This cause waste of precious energy. With an efficient heat exchanger system, this wastage can be reduced ( not entirely, as some amount of heat gets inadvertently wasted).

How to make a heat exchanger more efficient?
When a heat exchanger is installed, maintaining the difference between the hot fluid and coolant is very essential.  The coolant always needs to be at a lower temperature than the hot fluid because if the coolant is lower than the warmer coolant temperature, it will take more heat out of the hot liquid.
Another important point to be considered is the flow of the fluids between the both sides of the heat exchanger. While a greater flow will mean that the rate of transferring the heat will increase, it also will result in a greater mass that will cause an increase in velocity and pressure loss.

It must be remembered that a heat exchanger should always be installed by keeping manufacture guidelines in mind. Each heat exchanger comes with a different type of directives and its specific requirements. It must be noted that heat exchangers should be allowed for easy servicing and easy maintenance. When heat exchangers are used in industry, it becomes even more important that they are regularly cleaned and maintained.

Liquid Process Systems, Inc. have years of experience in providing customized heat exchanger systems, heat recovery systems,  pumping and filtering systems to serve a wide range of industries across many industries.

Industrial Filtration Systems and Solutions

Heat transfer  fluids or hot oils  are used for  the indirect  heating of processes. The hot oil is circulated between hot oil boilers and reactor vessels,  tanks,  molds,  calenders,  extruders,  or heat exchangers.

These fluids are subjected to temperatures ranging from 300°F to 750°F depending on the need of the process industry. Over a period, however, the hot oils degrade.

Some of the contributors to degradation of the thermal fluid are…

• Exposure to oxygen (air)
• Low velocity of the fluid through the heating chamber and piping
• Improper heater selection
• Operating the system at temperatures above manufacturer’s recommended maximum temperature.

Types Of Contaminants
Pipe slag, mill scale, dirt, and dust accumulated in the system during installation or maintenance could be the pollutants.

Problems caused by contaminants
With the increase of contamination in the system, the fluid undergoes drastic property changes that affect the heat transfer capability of the overall system. Some of the issues could be…

• Wearing of rotating components (pump impellers, gears and shafts, mechanical seals, valve stems, etc.)
• Increased energy consumption
• Reduced capability of heaters and heat exchangers
• Increased viscosity of the oil 

Such issues are overcome by liquid filtration system
 
Different Industrial Filtration Methods
Traditional Filtration Method
Incorporate a strainer before the system pump. Strainers are signed to protect a piece of equipment such as a pump, valve, or flow meter.
They capture particles, preventing the particles from entering the pump and eventually the system.

A strainer must be cleaned regularly to prevent cavitations, which causes mechanical seal failure or magnetic de-coupling.

Full Flow Method

Another liquid filtration system is to install a filter in either a side stream or full flow
arrangement.

For both the types industrial filtration systems, the filter consists of a filter housing with a basket made of stainless steel, with perforations designed to trap fine particles.

In the case of side stream installation, the inlet of the filter is installed close to the discharge of the pump. The fluid is diverted through the filter, cleaned, and removed to the suction side of the same pump or a low-pressure return line.

The most efficient filtration is a forced flow and sidestream system arrangement that incorporates a pump and filter designed for high-temperature use.

 This system has its filter pump to divert 5 to 10% of the process flow continuously through the filter as the heating system is operating. The entire fluid passes through the filter at least 15 to 20 times per day.

The inlet of the filter pump is plumbed into the discharge piping close to the process pump to take advantage of the turbulence in the tubing which keeps the solids in suspension.

The dirty fluid is forced through the filter, and the clean fluid is discharged into the same process line at a pressure higher than the system pressure or to the return pipeline downstream from the process pump.

​How Does A Heat Exchanger Work?

Typical industrial heating systems use water or steam as a heat carrier. But, at higher temperatures, both steam and water need high operating pressures. This may not always be desirable from an installation or safety standpoint.

Because the piping system requires more thickness that increases weight and thermal stresses. It needs special manufacturing techniques and safety procedures. This increases costs.

When considering industrial heating systems where high-temperature process output is required, maintaining high-temperature is important.

Liquid heat transfer medium has a definite advantage here. High-temperature levels can be maintained using synthetic heat transfer fluids or heat transfer oils without increasing operating pressure.  

The heat transfer oils are capable of withstanding very high temperature. Organic thermal oils can operate in temperature up to 6000F and some synthetic heat transfer fluids can even go up to 8000F.  The thermal fluid used in heat transfer could be glycols or specially designed oil and high operating temperatures are easily achieved at quite low operating pressures.

Thermal oil boiler heat exchangers use such liquid medium or thermal fluids for heat transfer. A thermal oil boiler fires through a helical coil and generates energy from the hot products of combustion by heating the coil through radiation and convection.

 The coil heats thermal oil or fluid that is pumped through the thermal oil boiler. The thermal oil heats coils in various types of heat exchangers. Unlike a water or steam boiler, this heating process of oil boiler heat exchangers does not heavily pressurize the system.

Components of Heat Exchanger Systems

Operating heat exchanger systems is not difficult if the components of a system are understood, how to start-up & shutdown the system properly and general operational procedures.

System components and their function - The system is made up of …

• A pump that pushes the heat transfer fluid through an insulated piping system to a heater to the processing equipment.
• A piping system that carries the fluid from one location to another in the most direct path. These could be rigid or flexible, made of steel, copper, aluminum or  brass pipes depending on the type of thermal fluids used
• There is an expansion tank on the system to allow for the expansion of the hot oil as it gets hot and contraction when the hot oil is cooled.
• Filtration units to remove particles from the system, some systems have in-line or sidestream (preferred method) filtration units. The in-line filters 100% of the flow, where the side stream takes 10% or less of the system flow rate.
• Heaters which are classified by the amount of BTU produced per hour and the fuel that is used to generate the heat such as electric, gas, oil, and wood.

Operation Procedure

A. Start Up

1.  The system pump is started to get the fluid flowing through the system.

2. Once a good flow is ensured, heat is applied in increments. The reason for this is to ensure that a turbulent flow is maintained through the heater (where the hot oil can remove just as much heat as the heater can supply to the coil in the heater) so that there is no thermal cracking of the oil.  The increments are continued until the heat transfer fluid gets to a viscosity of 10 cP (centipoise) or less.

3. Once the heat transfer fluid is 10 cP or less, the heater can be dialed to the required operating temperature.

B. Shut Down

1. The heater is turned off

2. The pump continues to circulate the heat transfer fluid to remove any residual heat that is in the heater, the process, and the pipes. For some systems, this may take awhile depending on the system size. The reason for this is to make sure that when the pump gets turned off, the residual heat in the various components of the system does not thermally crack the heat transfer fluid.3. Once the temperature has dropped to 200°F (93°C) the residual heat has been removed the pump is shut off.

Oil Heat Exchanger Problems
 

Normal leakage in thermal fluid systems. This consist of fluid seeping out from threaded fittings, flange gaskets, mechanical seals and valve stem and pump shaft packing glands. Any droplets formed will cool rapidly on exposure to air.

Extremely low volume leaks may produce a light gray smoke. This is an indication that the fluid is oxidizing immediately on exposure to air. This smoke may cause respiratory irritation if inhaled for a period of time as can any type of smoke.

Catastrophic Equipment Failure may result in the rapid release of large quantities of thermal fluid.

 If the total system pressure is low and the fluid is operating below its atmospheric boiling point, then the leak will consist of liquid that may spray a short distance before falling to the ground.

Higher system pressure may produce a finer spray that ejects a greater distance from the equipment; however, the relatively larger surface area of the droplets and their velocity will result in rapid cooling.

A severe potential for fires can exist if the thermal fluid flow is interrupted without causing the heater to shut down. Under this no-flow condition, the temperature of the fluid inside the still energized heater increases rapidly to well above its boiling point. Any equipment failures may result in spontaneous ignition of the leaking fluid.

These are some of the oil heat exchanger problems and each needs to be handled carefully.

Types of Heating Systems - Heater Boliers

The use of electricity in homes cannot be overemphasized. So, obviously, heating makes the electricity bill fatter than it should. From the straightening of rumpled clothes to cooking and to the heating of water.

 Heat has been the meet for most domestic needs, and has been the accomplisher of some of our basic survival activities. Heat, especially the one produced by heat boilers, is needed for different domestic purposes such as to administer warmth in our bathing systems, to cook most of our foods from their raw state, and for boiling of water for disinfection from germs before drinking.

Heat boilers are electric devices consisting of a metallic component, an insulated handle and a connector. They come in different makes and in different fashion but work on the same principle. Heating is brought about by the simple conversion of electrical energy into heat energy through the opposition caused over an electric current flux through an electrical resistor.

The electrical resistor is the heating element embedded in heat boilers which acts as converter of energy from the electricity we use to the heat we need to carry out some basic domestic activities.

These heat boilers serve as perfect devices to bring about any rise in temperature as desired by the user over the water to be heated. The conventional level for heating water suited for domestic purposes ranges from 300C to 1000C depending on the heating level preference of the user.

These home use devices suited for heating purposes have over time, been fashioned in different models. Some come with the metallic device bare and unenclosed. These types are used by simple immersion into the water to be heated and connected to an electric power supply.

Another fashion of heat boiler come as an enclosed vessel housing the metallic device containing the heating and the water to be heated. Some also have been designed to run automatically by switching off heating process at 940C or when it is near 1000C.

For bathing purposes, modern bath tubs and bathing showers come with heating elements wired in the bathing shower stands controlled by heat-preference switches to administer warmth at the demand of the user during bathing.

Heat boilers have become traditional home appliances that cannot be antiqued. Their method of uses is simple and easy to carry out. They come in cheap prices and do not consume too much electricity.

Importance of Electric Boiler Systems

The use of electric boilers in heating systems is becoming more and more commonplace because of its many advantages. They are excellent alternatives to gas boilers and are now being used as primary as well as additional sources of heating not only for homes and residential establishments, but for commercial facilities as well. An electric boilers system is a type of boiler system where heat and steam is generated with the use of electricity instead of fuel combustion. Although slightly more expensive to operate than their gas or oil-fired counterparts, electric boilers—especially those that are designed for use in commercial settings—are popular because they cost less to install and are simple to use and maintain. Commercial boilers are commonly found in locations like food processing factories, laundromats, hospitals, and other commercial establishments requiring alternative heating.

Electric boilers work by converting electrical energy into heat (thermal) energy at 100% efficiency, offering dependable, albeit variable overall thermal efficiency. In most cases, the use of an electric boilers system is a lot more advantageous than gas powered equipment. In fact, experts agree that commercial boilers that use electricity are superior to oil/fuel heated boilers in a lot of ways. Many even say that electric systems may in fact be cheaper in the long run, not to mention being more environment-friendly. Electric boilers also win in terms of ease of use and installation, as they require less equipment to operate than traditional boilers. More compact than usual gas boilers, these systems can easily fit into small areas, making them an excellent choice for those who want to maximize space.

Choosing between an electric and a fuel heated boilers system should also be a matter of operational safety. Traditional fuel powered boilers typically require multiple equipment and parts in order to operate successfully—a stark contrast to electric boilers, which are incredibly simple devices to install and use. Electric boilers don’t require complex forms and methods of heat exchange, eliminating many of the hazards that are usually present in fuel heated boilers. Moreover, electric boilers are a lot easier and cheaper to maintain because they have no need for expensive tube and parts replacement that gas powered devices and systems often require. Whereas fuel powered boilers conk out because of fuel and soot residue, none of these contaminants hinder the smooth operation of electric powered boilers system. Sustainability is also a major benefit because they require less energy to ensure efficient operation.

Heat Exchanger: An Effective Equipment for Industries

Heat exchangers—whether they be in compact, diffusion bonded, or shell-and-tube form—offer a world of advantages in a wide range of industry applications. The oil and gas, chemical processing, and power generation industries are among the many sectors that benefit from a myriad of performance-related and monetary benefits of using of heat exchangers and related products. Here are some of the most significant benefits different industries can expect from utilizing industrial heat exchangers in their day to day operations:

• Innovative heat exchanger systems and technologies offer tremendous advantages particularly in maintaining performance at extreme pressures and temperatures. Heat exchangers are widely used in an extensive range of light hydrocarbon liquid and gas processing duties, in conjunction with different types of heavy duty machines and units and assemblies that range from 6 to 100 tons. This is why there is a huge market for heat exchangers and related equipment in the oil and gas industry. In fact, oil and gas companies are some of the longest standing and most established markets that heat exchanger suppliers cater. Heat exchangers are truly invaluable in keeping oil and gas operations up and running.
• Power generation industries also benefit from heat exchanger equipment, which provide safe and reliable temperature equalizing properties during critical processes and applications like energy recovery, storage, and solar thermal energy generation. Advanced heat exchanger technology enable optimal effectiveness in power plant operations, thus helping companies translate greater returns through cost-effective, highly reliable solutions in every aspect of their implementation.
• Heat exchangers are likewise critical in chemical processing industries. Heat exchange units and machinery can be designed and modified according to industry needs so that features and capabilities can be tailored to processes that are crucial to industry operations. Bespoke solutions like these allow for maximization of output. In chemical processing plants, heat exchangers are often used in compact steam reforming, passage reactors, as well as adiabatic bed reactors, among many chemical reactor applications.
• Industrial gas markets also need robust heat exchange systems, particularly in regulating energy demands generated by processes like cryogenic air separation. Industrial gas industry clients often request for tailored systems that enable them to optimize the operational performance of their machinery, all while minimizing costs. Heat exchanger systems are used in industrial gas markets to complement different types of air processing technologies, allowing enhanced effectiveness of entire systems, while making sure that overall footprint of equipment is reduced, thus enabling more environmentally friendly and health-conscious operations. Heat exchange systems benefit industrial gas markets by helping ensure reduced risk of explosion and other related incidents, especially in environments where mercury and similar types of elements are used and at high risk of contamination.

With the highly sensitive and demanding applications that heat exchangers cater, it is crucial that you find reliable companies that supply advanced, well-designed, and duly insured equipment that are built to meet all the demands of your particular industry. The best companies are constantly on the lookout for bigger and better ways to provide support for the different industries they serve.