SI RICE NESHAP — Business Opportunity for Engine Distributors & Packagers

Emission control technology that will be used is Oxidation Catalysts. One needs to be aware of the type of coating on the catalyst element's substrate. Platinum coated substrates are more durable than Palladium. Platinum lasts longer and is more robust to poisons like sulfur. SI RICE NESHAP requires CO reduction. Most catalysts on the market today are calibrated on the order of 90% CO reduction which may exceed your actual reduction needs and therefore cost more. Look for a catalyst provider that can adapt to these lower CO reduction requirements. 4SRB non-emergency 100 to 500 HP at major sources and 4SRB non-emergency >500 HP at area sources require formaldehyde reduction. Oxidation catalysts and Non-selective catalytic reduction devices are used for this purpose.

Engine backpressure also needs to be considered when adding a catalyst to an existing engine. Adding a catalyst will add backpressure that may exceed the engine exhaust backpressure threshold. A catalyst can add an additional 3-4” of water to engine backpressure. Replacing the silencer with a combination silencer/catalyst unit is a solution to minimize the additional backpressure. They are designed for lower backpressure by reducing the number of expansion and contractions of the exhaust gases. Another option is the catalyst itself can be designed for lower backpressure.

Placement of the catalyst in the exhaust system is critical as the exhaust gas temperature needs to be managed so the catalyst works properly. Most catalysts need to operate above 250 degrees C. The further the gas path is from the source, the lower the temperature. In some applications, this may require additional insulation around the exhaust system in order to maintain the proper exhaust temperature. The system should be optimized for the lowest temperature seen throughout the year. For example, colder climates may need additional insulation because of winter temperatures. Also, proper attention needs to be paid to the components upstream from the catalyst system. If you are using a packed silencer in sequence with the catalyst system, fibers may come loose that may coat or plug the catalysts element and reduce its effectiveness. In these instances, the catalyst system should be located upstream from the packed silencer.

Before installation of the catalyst system, the physical support structure needs to be considered. For larger catalyst systems, the connecting pipe will not be able to support the catalyst’s weight. A steel ladder system may be required to support the catalyst from the package’s base. The supportive structures should be fabricated before on-site installation to minimize service time.

Proper attention needs to be given to catalyst sizing. The volume of the catalyst most be properly sized for the exhaust flow rate to meet the required emissions reduction target. If it is undersized, you won’t meet the emissions target. And if it is oversized, the catalyst may be overpriced and uncompetitive when selling to an end user.

Catalyst Configuration & Service

Catalysts require periodic servicing, typically every 8700 hours of operation. The catalyst system needs to be placed where it can be easily accessed, whether near a service panel or open area. Engines less than 500 HP may utilize a more economical disposable/non-service catalysts housing. For larger HP Engine applications, it is more cost effective to utilize a removable catalyst element housing design. This design should allow easy access and removal to the catalyst element without special tools or cumbersome capture mechanisms. The quicker to remove and replace the catalyst element, the more time your technicians have for other billable jobs. Exhaust bypass is a common problem in some catalyst housing designs. This is where the exhaust gas circumvents the element and is not forced through the catalyst. This issue will impact the effectiveness of the catalyst system. Seek a housing and catalyst design that includes a positive seal against the side of the housing, forcing the exhaust gas to flow through the catalyst element.

Many engines that will be affected by the SI RICE NESHAP ruling will come in enclosed skid-mounted packages. Space inside the enclosures is at a premium. Finding a location to fit a catalyst can be difficult. However, by utilizing an integrated silencer/catalyst system, you may be able to place it in the same footprint as the current silencer. Also, you will need catalyst housings that have different mounting configurations, such as end-in/end-out, side-in/end-out, and high-side in/end-out.

Existing stationary engines that require the addition of a catalyst system require before and after emissions testing to validate compliance. To make this requirement easier for your organization, work with an emissions control supplier who can provide the testing. In this way, the emission control supplier can receive information immediately if changes need to be made to meet compliance.

An additional opportunity for your organization is continuous monitoring requirements. The SI RICE NESHAP ruling requires engines that are larger than 500 hp and are a major source of hazardous air pollutants to maintain a service log of catalyst differential pressure and temperature. You can sell and install a continuous monitoring system to make this documentation requirement easier for your customer. Offer a continuous monitoring device that allows the storage of multiple readings. Also, a monitoring device with CANBUS capabilities will allow integration into a facilities Building Automation System. Or, you may want to consider offering a monitoring service to your customers that will handle the data tracking requirements for a monthly or yearly fee.

Labor time to retrofit an existing stationary engine is quite variable. One needs to consider the catalyst systems size, weight, site accessibility, lifting equipment, if the package is enclosed or open and installation complexity. Because compliance requirements aren't until Aug 10, 2013, you have time to actively seek some test project sites to hone the skills and techniques required before the majority of the retrofit projects take place in late 2012 and early 2013.