Case Studies

Eliminating De-Rate and Maximizing Fuel Flexibility

EES conducted a successful demonstration on a 750MW tangential fired PC boiler using EES^© CoalTreat™ technology for controlling slag in PRB boilers. The objective of the demonstration was to reduce molten slag and prevent plugging on the front face of the reheat section.

Engineered Modifications to Solve a Refinery Package Boiler’s Vibration Issues

A package boiler at a refinery had a long history of vibration issues. In lieu of burner replacement, STEP suggested an engineering first approach beginning with a holistic system review. The STEP Combustion recommended modifications were installed in parallel with a new control system. The system was commissioned and is successfully operating at ~4% O2,<25ppm NOx, and <50ppm CO. O2 was reduced from 6%to 4% improving boiler efficiency and NOx was reduced from 100ppm to 25ppm.

Biomass Slag Mitigation

EES provided an AddChem-30 fuel pretreatment system to eliminate slag formation by altering ash chemistry. The slagging was eliminated, and the boiler is now running much more smoothly, doubling the downtime between outages, and reducing maintenance.

KLeeNwater ELG demonstration unit

A five gallon per minute KLeeNwater ELG demonstration unit was installed at a major utility to determine the most cost effective treatment program to meet ELG limits for either treat and discharge or zero liquid discharge (ZLD) scenarios.

KLeeNwater Scrubber Fines Dewatering Case Study

A newly commissioned FGD Fines Thickening Clarification System was not performing as expected. After performing a study, EES recommended specialty chemical solution enabling reduced costs, elimination of compliance issues, and improved gypsum profit.

Boiler Tuning for Emissions Compliance
An international chemical company needed to reduce NOx/CO emissions on their package boiler to meet state permit limits.

Burner Vibration of an Oil Fired Industrial Air Heater
A mineral supplier with an industrial air heater used for spray drying was experiencing problematic vibration.  After unsuccessful attempts to eliminate the vibration through tuning and OEM recommended changes, the customer contacted STEP for an onsite evaluation.

Combustion Diagnostic Testing
A utility boiler was de‐rated due to elevated opacity levels during high load operation.  STEP was contracted to provide field diagnostics in order to evaluate the root cause of the elevated opacity as well as to provide an action plan for opacity mitigation and future preventative measures.

Package Boiler Burner and Induced Flue Gas Recirculation System
A utility needed to convert their single fuel (heavy oil) to dual fuel (heavy oil and natural gas) boilers and reduce NOx emissions.

 Dual Fuel Wall‐Fired Boiler (230t/h)
An overseas industrial high‐tech materials manufacturer needed dual fuel burners and additional equipment for their new coal and natural gas fired boiler.

 Electrostatic Precipitator Capture Efficiency Improvements
A utility boiler equipped with a cold‐side electro‐static precipitator (ESP) is subject to chronic elevated opacity levels.

Sound Attenuation Analysis
A marine customer had to reduce the NOx emissions of a quad engine ferry utilizing a selective catalytic reduction (SCR) system.  The SCR catalyst and housing would replace the existing silencer, and the customer needed to verify that noise levels would remain the same.

Transient Piping Analysis
A utility boiler was experiencing regular opacity spiking during start‐up, along with burner trips and instability. Recent operation as a peaking unit with a high frequency of starts and stops, the utility needed to improve the opacity and reliability  during light‐off and warm‐up.

Canadian Oil Refinery Engineering Study
STEP analyzed various technology combinations from a technical and economical aspect to narrow down the options to meet to meet BLIERS and MSAPR regulations.

NOx Reduction from Waste Steam
STEP Combustion successfully utilized waste steam to reduce NOx emissions by up to 69% with no impact on CO or stability in a catalyst activator burner.

Diverging to Low NOx
The aerodynamics of the diverging throat burner are optimal for Low-NOx performance. The internal recirculation Zone (IRZ) creates a stable core flame and allows for the balance of the fuel to stage down the furnace, reducing NOx emissions.

 Gas Conversion and Low NOx Retrofit of a 450 kpph Tangentially Fired Boiler
A North American utility company needed to convert a tilting tangential oil‐fired boiler to a dual fuel (natural gas and oil) unit. Additionally, heavy oil NOx emissions were to be reduced from the current low NOx burner levels.

STEP Variswirl staged burner with optional gas injection configurations
A corn ethanol plant’s burner produced severe harmonic vibration throughout the combustor and was unable to safely operate above 25% of the required heat input. As a remedy a STEP Combustion Variswirl burner was commissioned and is successfully operating at <3% O2, <60ppm NOx, and 0ppm CO. Stability was proven with a remarkable 15:1 turndown with no vibrations.