Dedicated To Operational & Energy Efficiency, Natural Resource Conservation & Carbon Footprint Reduction

1. Frequently Asked Questions

 

 

1. How is the EVCR Unit more efficient, more economical, and permanent in comparison to existing conventional mechanical steam traps?

The job of any condensate removal device is to keep BTU rich steam in the system and while ridding the system of the condensate that forms continuously as steam gives up its latent heat and condenses. Water in a steam system reduces heat transfer and causes erosion, corrosion and water hammer. It is critical to purge it quickly, completely, and efficiently.

On day one, a properly sized EVCR Unit is more efficient than a brand new mechanical trap - Every condensate removal device, be it an EVCR Unit or a mechanical trap, has an orifice. Whereas the EVCR Unit extracts condensate through a non-moving, continual flow technology; a mechanical trap operates on a batch system - they open in the presence of condensate and close in the presence of steam.

A properly sized EVCR Unit operates continuously in the lower end of a Steam Loss to % Condensate Capacity chart while a mechanical trap (whether it’s open/shut mechanism is activated by internal floats, buckets, bimetals, bellows or discs) ramps up into the upper ranges every time it opens. Therefore, in normal operating steam processes, a properly sized EVCR Unit is usually 3% to 5% more efficient than a perfectly operating brand new mechanical trap.

This superior performance only increases as the mechanical trap begins to wear out. On 24-hour-a-day applications, mechanical traps cycle several times a minute or a couple of million times a year, resulting in wear and leakage. Though mechanical traps average about a 3-5 year lifetime before total failure, the wear and tear from the repeating purge cycle results in the initiation of performance degradation long before that. Due to this degradation, it is not unusual for the entire mechanical trap population of a plant to be operating at 15% to 30% below its maximum, brand new efficiency. On the other hand, since the EVCR Unit has no moving parts, it doesn’t wear out and the efficiency experienced in year ten will be exactly the same as that experienced on day one.

 

2. Why is the EVCR Unit superior to existing mechanical trap technology in handling varying loads?

With the EVCR Unit, steam traveling at the speed of sound continuously forces much slower condensate (about 30 mph) through a precisely sized hole, blocking steam from escaping. The EVCR Unit is sized to handle 100% of the condensate load produced by a particular application. At 100% capacity, it is easy to understand that an accurately sized orifice device loses no steam and backs up no condensate. But varying, not constant, loads are the norm.The question is how well does the EVCR Unit handle this varying capacity – does it lose inordinate amounts of steam?

Actually, the opposite is true. First, since the EVCR Unit continually removes condensate from a system, the size of the EVCR Unit orifice opening is significantly smaller than that of the orifice in a mechanical steam trap because it has to be large enough to handle the batch processing of larger periodic loads.

Secondly, a continual flow technology is subject to the dynamics of two-phase flow physics. When the load drops below 100% capacity, the physics of two-phase flow, along with the magnification effect the venturi design, causes a violent turbulent mixture of steam and water. The turbulence of the significantly heavier and denser water results in a shield that prevents steam loss as the water works its way through the orifice. Even as the varying load drops to 68% of capacity, no steam loss will occur through the venturi orifice due to this turbulence. As the load continues to drop below 68%, the turbulent effect still continues and only allow negligible steam loss.

For instance, in a 100-psi system producing 375 lbs/hr condensate, an accurately sized Enercon unit loses 1.76 lbs/hr steam if load drops to 25% of capacity, which it will do only sporadically. At 100 psi, according to the D.O.E. and trap company ‘Leaking Steam Trap Discharge Rate’ charts, a failed conventional trap with a 1/8” internal orifice loses 52.8 lbs/hr.

We recommend our units for applications where the load may drop as low as 25% of capacity, although sources such as the U.S. Naval Facilities Engineering Command Supplements (10-90 & 1-92) say ‘a fixed orifice sized for a 100% load operates efficiently down to a 10% load.

’ Hampton Affiliates, a leading lumber company which converted multiple mills to the EVCR Unit system in 2003-4 says: "Our operations are all zone control, so we have a constant variable load situation. (Enercon) traps perform with excellence in this type of environment." (Timber Processing magazine July/Aug. 2004)

 

3. What are the anticipated financial and performance results in a complete facility conversion from mechanical traps to EVCR Units?

What are the results? Historically, upon installation of the EVCR Units, our customers typically report 10%-25% fuel savings, save similar amounts of water necessary for steam production, virtual eliminate steam trap maintenance expenses, reduce condensate related equipment damage and experience solutions to some of their steam related problems such as low and inconsistent temperatures, trap-related pressure drops, high back pressure and water hammer.

What does that mean in terms of fuel savings? As the price of fuel has dramatically increased over the past several years (from $1.60/mcf to over $7.00/mcf for gas users), the savings from a more efficient steam system have also increased dramatically.

For example, at $7/mcf; a facility that runs 100,000 lbs per hour of steam through its 500 unit trapped system and has a typical inefficiency rate (due to both totally failed traps and leaking functioning traps) of 15%; the annual fuel savings calculate to $893,000.To this figure is added the economic benefit of increase operational efficiency, savings from water conservation and its related chemical treatment, plus savings on maintenance and equipment repair. The result is that most customers experience project paybacks less than 12 months with some extreme cases experiencing payback less than 3 months. And these savings are repeated annually as the EVCR Units are a permanent solution.

 

4. What are the results of conversion to the EVCR Unit when a company believes it has a first rate steam trap maintenance program?

TO ACHIEVE LESS THAN A 5% TRAP FAILURE RATE, The Department of Energy (Energy Tips - 6-99) states that a facility needs to perform weekly inspections of its systems 150 psig and above, monthly inspections of its systems in the 35 psig to 150 psig range and annually inspect its systems below 35 psig.

Almost every production and maintenance person will tell you that this level of testing is unrealistic. Plants do not have maintenance budgets that allow for such manpower. Just the weekly testing of a 500 unit paper mill would require two, or more full time persons. Then add to that the personnel necessary to change faulty units as they are found along with the cost of replacement traps, fabrication, sectional shut down, and installation and you can see that such recommendations are just not practical. Steam traps are typically viewed as a low priority item and are changed on an ‘as needed’ basis.

As a Result; ‘”Even for companies with annual test-and-replace programs, studies show the average trap has been leaking for six months before it is replaced.” (Textile World - February ’02). The Alliance to Save Energy claims its studies show that on average 15% to 20% of steam traps in a facility will be inoperative – completely failed either open or closed. An English study claimed that 36% of the traps it examined were not functioning properly.

ENERCON UNITS ARE PERMANENT. EVCR Units in plants converted as long as 14 years ago have not needed any maintenance, a replacement, or lost any measurable condensate removal efficiency from the day they were installed. As long as a system does not have chemical problems that eat away piping, the EVCR Unit is typically a maintenance free, permanent solution.

 

5. In what type of applications do the EVCR Units efficiently operate? Thousands of EVCR Units are operating efficiently on tracing lines, unit heaters, humidifiers, drip legs, submerged coils, heat exchangers, jacketed coils and other applications. On completely converted plants, Enercon technology has been applicable for and replaced, on average, 99% of existing conventional traps.

It is company policy that we will not ship an EVCR Unit if it cannot perform the task involved or if there is not an economic benefit for an existing steam trap to be changed out. In the rare instance where Enercon technology is not appropriate, we will tell you what the correct alternative is.