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Increased bookings for RHZ

Increased bookings for RHZ

RHZ is pleased to report that demand for high quality service is on the rise - so much so that we are massively overbooked. There aren't enough hours in the day for us to meet the demands of all the potential customers who need IMMEDIATE access to our services. In the last three months alone, we have several large new customers requiring routine maintenance as well as on-demand emergency support and special improvements to their pollution abatement systems. As a result, we are actively adding to our RHZ team.

The Cost of Taking Shortcuts

Gas meterTaking shortcuts may be a short-term gain for OEMs and contractors, but they inevitably lead to long-term problems.  Sure, shortcuts lower overhead and increase profit margins in the short term, but at what cost? Failing tests, compromising system integrity, suffering catastrophic failure, and losing a customer’s trust are risks that should always be considered whenever a contractor or OEM thinks about taking a shortcut.

Mechanical shortcuts often compromise a system’s integrity, leading to costly repairs and failed tests. For instance, I remember working on an RTO that utilized tadpole gaskets in the seats of its butterfly valves. During an inspection I found numerous valve seat bolts were broken. This prevented the valves from properly seating against the gasket. Nearly half of the bolts on one valve had failed. On this particular valve, that meant 14 busted bolts (out of 32 total). How does someone ignore something so critical? The crews who worked on these valves must have assumed that the remaining bolts were “good enough” to pass the upcoming EPA test. However, the consequences of their ill-advised shortcut quickly countered the time they saved in the field.

Bakeout Cures Excessive Pressure Swings

Bake-out in progress. The picture was taken during the bake-out. The orange streaks are embers, and the temperature inside that vessel was around 850F at the time the photo was taken.This past weekend I performed a bake-out on a five tower RTO. For the past few months, this unit had been operating as a four tower due to excessive pressure swings, from 15" WC to over 31" WC. These pressure swings forced the plant to shut down multiple sources, adversely affecting their production. The swings also played havoc with the 140,000 CFM draft fan, placing an inordinate amount of stress on the main draft fan, as it tried to maintain a consistent inlet static pressure. The result was excessive and rapid speed fluctuations. The resulting stresses fractured the 6 foot diameter wheel in multiple places.

After the bake-out, the RTO began operating as a normal five tower. The pressure swings were gone, replaced with a consistent inlet static pressure. The unit now operates with a modest differential pressure drop (between 9 and 10" WC).

Stabilizing thermal oxidizer operation in PSA facilities

Over the past year I've been working on stabilizing thermal oxidizers used in conjunction with a two stage pressure swing adsorption process. PSA is a popular method of refining biogas to create biomethane - a valuable green commodity.

Oxidizers and Heat Exchangers: Improving the bottom line

A number of systems utilize heat exchangers. Their most common application is to preheat the incoming waste gas stream. By preheating the solvent-laden air before it enters the oxidizer the burner(s) do not need to generate as many BTU's to achieve the combustion chamber set point. This reduces utility consumption.

For Example:

Commissioning Concerns: oxidizer mode issues resolved

During commissioning of a thermal oxidizer that used a bypass fan to maintain source static pressure during offline operation, some minor issues arose. When switching between bypass and online modes one, or both, proof of flow switches (for the main draft fan and combustion blower) would momentarily drop out. This resulted in the burner shutting off, which would shut down the oxidizer. Another issue was the dramatic fluctuation in static pressure that occurred during mode switching. The client was very concerned the momentary drop in static pressure could adversly affect their production.

Ship & Shore Two Tower RTO passes EPA tests

After optimizing the new Ship & Shore Two Tower Regenerative Thermal Oxidizer for testing (it had been achieving a Destruction Rate Efficiency around 92% when I arrived) the unit excelled in its EPA tests - achieving Destruction Rate Efficiencies between 97.9% and 98.2%.

In addition to passing the tests, plant sources were balanced. This reduced air volume by 33% - giving the unit more more capacity while reducing gas consumption by nearly 36%. The facility listened to our Scrubber recommendations and have taken steps to correct a fatal flaw that could destroy their new RTO.