A Plan to Retrofit Three Diesel Generators with the Rypos / Bekaert System

This page updated November 23, 2005.

Rypos Inc.

A Plan to Retrofit Three Diesel Generators
with the Rypos / Bekaert System

CARB Grant Number ICAT 01-6


The statements and conclusions in this Report are those of the grantee and not necessarily those of the California Air Resources Board. The mention of commercial products, their source, or their use in connection with material reported herein is not to be construed as actual or implied endorsement of such products.

Objective
The objective of the ICAT project was to demonstrate the capability of the RYPOS TRAP diesel emission control system to remediate particulate matter from diesel exhaust. This report presents the results of a field demonstration of the RYPOS TRAP. This demonstration was partially funded by the ICAT program of the California Air Resources Board. The RYPOS TRAP is an actively regenerated diesel exhaust particulate trap that is self-cleaning and automatic in operation.
Rypos Trap
The RYPOS TRAP is a highly effective Diesel particulate filter for exhaust emission control. The system consists of filter housing, flow control, electrical control circuit, and removable filter cartridges. The trap itself is composed of fine metal fibers that are shaped into filter elements and then incorporated into filter cartridges; these sintered fibers are capable of capturing the very fine carbon particles present in the exhaust stream. It can be used alone or in conjunction with a Diesel oxidation catalyst to reduce the soluble organic fraction, gaseous hydrocarbons, and carbon monoxide while suppressing the formation of sulfate.

It is an active regeneration system (controlled regeneration) with high efficiency and soot holding capacity and is regenerated independently of the exhaust temperature. The filter element is electrically heated while the exhaust flow is reduced, thereby saving considerable energy during the regeneration cycle. Each element, which represents a small fraction of the total filter, is regenerated individually to reduce the maximum amount of electrical energy required. In a medium size engine (100 hp - 200 hp), fuel penalty is less than 1% of the rated horsepower of the engine.
The RYPOS TRAP also serves as a sound absorption device and can be designed to fit the same envelope as the muffler or catalytic converter it replaces.
Field Demonstrations
The field demonstration consisted of a nine-month series of tests on three electrical backup generators, all located in Riverside, California. The generators were rated at 100 kW, 225 kW, and 350 kW. Measurements of the diesel emissions were made before installation of the RYPOS TRAP, after installation of the trap, after accumulation of 100 hours of operation under varying load conditions, and after removal of the trap. This provided an accurate record of the performance of each RYPOS TRAP.
The demonstration showed that the RYPOS TRAP can effectively remove total particulate matter from diesel exhaust, and regenerate (clean) itself reliably independent of engine exhaust temperature or fuel sulfur content. During these demonstrations, the backpressure remained within acceptable limits.
Measurements And Results
Before the installation of each of the RYPOS TRAPs, the following operation characteristics of the diesel generator were monitored to help evaluate the performance of the trap:

a. Engine Load

b. Engine Speed

c. Exhaust Temperature.

Exhaust samples were collected before and after the installation of the systems and the Total Particulate Matter (TPM) measurements were used to evaluate the Traps’ efficiency.

100 kW System

200 kW System

Load

Efficiency

Idle

78%

40 kW

86%

80 kW

89%

Load

Efficiency

Idle

85%

125 kW

86%

175 kW

91%

Figure 1 below shows the pressure profile of the 100 kW generator, running for a day. The pressure measurements were taken every second. Different segments of the graph depict different engine load settings:
  1. Idle, for about 1 hour

  2. 40 kW, for about 3.5 hours

  3. 80 kW, for about 30 minutes.
Figure 2 shows the backpressure for the 225 kW generator, after the installation of the RYPOS TRAP. As in Figure1, the following settings can be distinguished:
  1. The first part shows the engine idling for about 30 minutes.

  2. The second part, 125 kW for about 20 minutes.

  3. The third part, 175 kW for 20 minutes.

Figure 1

Pressure Drop (mbar), 100 KW Caterpillar Diesel Generator, May 13, 2002.


Figure 2

Pressure Drop (mbar), 225 KW Caterpillar Diesel Generator, May 17, 2002.


Energy Penalty

100 kW Generator

Setting

Regeneration
Duty Cycle

Energy
Consumption

Energy
Potential (%)

Idle

20%

0.3 kW

NA

40 kW

35%

0.53 kW

1.3%

80 kW

50%

0.75 kW

0.9%

225 kW Generator

Setting

Regeneration
Duty Cycle

Energy
Consumption

Energy
Potential (%)

Idle

10%

0.3 kW

NA

125 kW

20%

0.6 kW

0.5%

175 kW

30%

0.9 kW

0.5%

350 kW Generator

Setting

Regeneration
Duty Cycle

Energy
Consumption

Energy
Potential (%)

Idle

20%

0.6 kW

NA

50 kW

33%

1.0 kW

2.0%

150 kW

100%

3.0 kW

2.0%

The “Energy Penalty” reflects the percentage of average power consumption needed to regenerate as compared to the power generated by the engine. Notice that for both the 100 kW and 225 kW generators at “Idle,” the PM production is minimum, which results in the minimum regeneration duty cycle. As the PM production increases, the regeneration duty cycle increases from about 20% to 50% for the 100 kW generator and from 10% to 30% for the 225 kW generator.
The system used in the 350 kW generator was under-sized on purpose to help us optimize our design, this resulted in higher regeneration duty cycle and relatively high energy penalty.
Conclusions
The completion of the ICAT demonstration program has shown that the RYPOS TRAP is a viable solution to the problem of particulates in the exhaust of diesel engines operated under low exhaust temperature or high sulfur fuel conditions. During this demonstration program, the RYPOS TRAP maintained consistently low back pressure under a variety of engine loads, and stayed within our target for regeneration efficiency.

Funding Source

Funding Amount


ICAT

$100,000

Grantee

$  24,750

Bekaert Corp.

$  76,810


Click here for the entire final report.




ICAT Funded Projects

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