Performance Test for
Removal of Hydrogen Sulphide and Ammonia
Deodorant Effect of "ACF-32"

Test Report

January 2008

Wellab Limited
Unit C, 1/F, Goldlion Holdings Centre,
13-15 Yuen Shun Circuit,
Siu Lek Yuen, Shatin, N.T.
Tel: (852) 2898 7388 Fax: (852) 2898 7076

TABLE OF CONTENTS

1 OBJECTIVE
1.1 The test was performed by Wellab Limited on 8th January 2008 and the objective of the test was to determine the removal efficiency of a liquid deodorant called ACf-32 provided by Cinotech Solution Limited.

1.2 On 8th January 2008, the liquid deodorants were delivered to Wellab for testing its efficiency in removing hydrogen sulphide and ammonia gas of a known concentration.

2 THE REACTION CHAMBER
2.1 An air-tight reaction chamber was established with size 0.4m x 0.4m x 0.8m. A schematic drawing is shown in the following diagram:

2.2 In the chamber, a circulation fan has been installed near the sample injection port to disperse the liquid deodorant sample.

2.3 The reaction chamber has one sample injection port, which is centrally located on the side for the application of liquid deodorant sample. The sample injection port was equipped with a 0.3 mm orifice diameter nozzle.

2.4 The reaction chamber also has a separate gas injection port, which is located at the top of the chamber, for introducing hydrogen sulphide (H2S) and ammonia (NH3) gas to fill the chamber.

2.5 A detection port was set directly opposite to the sample injection port, in the reaction chamber. The detection port was used for collecting air sample inside the chamber by an air pump for H2S/ NH3 gas measurement.

2.6 The following photos show the set-up of the reaction chamber:

3 TESTING PROCEDURES
3.1 During the test, the reaction chamber was filled with standard testing gas (H2S or NH3) through the gas injection port and allow for mixing/stabilization after introduction of the standard gas by operating the circulation fan. The reaction chamber was stabilized at normal laboratory room temperature/relative humidity and without any pH adjustment. This initial H2S concentration within the chamber should be at the targeted level of 25  5 mg/m3. This initial NH3 concentration within the chamber should be at the targeted level of 5  2.5 mg/m3

3.2 After mixing/stabilization, an air sample from the chamber through the detection port was collected and measured its H2S/NH3 gas according to ISC 3rd ed. 701 and 401 . The rate of air sampling rate was suitably adjusted such that the air sampling time was at least 1 minute while the minimum detection level of 1 mg/m3 can be attained for the H2S/ NH3 measurement. The temperature and relative humidity within the reacting chamber were recorded as well.

3.3 A specified volume (21mL) of liquid deodorant sample through the sample injection port was applied at an appropriate injection rate (in mL/min).

3.4 An air sample was collected from the chamber through the detection port after application of the liquid deodorant sample for 1 hour and 5 hours. The H2S/ NH3 gas concentration in the air sample was measured. The temperature and relative humidity within the reaction chamber were also recorded.

4 TEST RESULTS
4.1 The performance test was conducted on 8th January 2008. The test results are shown below:

5 CONCLUSION
The test results show that ACF-32 could reduce both hydrogen sulphide and ammonia gas content, resulting in significant reduction…almost elimination of odors.

Mark Krupka, VP Technology, Microbiologist from Rutgers University, comments…

I agree with Dr. Choy's conclusion from the data above, ACF-32 does have a positive effect in reducing hydrogen sulfide, though to what extent will depend on the exact environmental conditions being treated.

A septic tank usually has different zones with respect to redox potential, and, as a result, on the type of bacteria that will function in each zone. Since a septic tank is not sealed, there is a headspace with air that is in contact with the surface of the septic tank. For this reason, the top 3 - 5% of the tank will be aerobic if the septic tank has typical loading. Below that there will be a microaerophilic zone where there is a little oxygen and the redox potential is still positive, but low. Next, is a combined anoxic and anaerobic activity, depending on the availability of oxygen bearing inorganic compounds, primarily nitrate and sulfate, and the organic load. It is the facultative anaerobic activity of Sulfate Reducing Bacteria (SRB's) that results in the generation of hydrogen sulfide.

The sulfide oxidizers in ACF-32 can function on the aerobic and microaerophilic zones, so you have competing reactions. The SRB's are generating hydrogen sulfide and the sulfide oxidizers are converting it to elemental sulfur or sulfates. The balance of these reactions dictates how much residual hydrogen sulfide that will be left.

By sealing the bottles in the above documented test, the aerobic and microaerophilic zones, which you would find in most anaerobic environments, were reduced or eliminated. This then favors the SRBs, so the experimental design was skewed in favor of hydrogen sulfide production. Despite this, the ACF-32 was still able to show consistently less hydrogen sulfide than the control and other units.

As such, I am confident that if the experiment were run with the reactors unsealed, assuming that they would have a neck that would limit oxygen transfer, but in a way the hydrogen sulfide could be collected, it would more accurately reflect a septic tank environment, and that ACF-32 would show even better results. Bottom-line, ACF-32 will prove to be far more economical than any other chemical alternative in a real septic tank environment,

In BioDigesters (Municipal or Agricultural) used to produce Methane, ACF-32 has been proven to reduce sludge by 25 to 30%, resulting in upwards of 40% more BioGas (Methane), while eliminating the production of Hydrogen-Sulfide. This will certainly be the case in septic systems as well.