I-DEV0409: Deviations on i) the monitoring point of COD of POME leaving closed tank digesters, ii) frequency of monitoring of COD in the project activity, iii) monitoring of biogas Calorific Value, and iv) method of measurement for loss of biogas from pipeline

The request for deviations is for a registered CDM project activity “Kim Loong Methane Recovery for Onsite Utilization Project at Kota Tinggi, Johor, Malaysia (project reference no. 0867)” which is registered against AM0022 version 3 on 8 April 2007. During the first periodic verification, as per the requirement of VVM para 210, SIRIM QAS Intl. found that the project participant (PP) had deviated from the provisions of the registered monitoring plan. Four deviations were found as follows:

i) Deviation no. 1 – monitoring point of COD of POME leaving closed tank digesters (monitoring I.D.3-4)

According to the monitoring plan in the registered PDD, the monitoring of COD leaving the closed tank digesters (I.D.3-4) is to be measured daily (during the first year). In the project activity, there are 3 closed tank digesters. During the period from 1 February 2009 to 31 July 2009, PP had measured the COD at the outlet from each tank, and I.D.3.4 was taken as the average of the three measured values rather than taking the measurement at a common point at the outlet of the three tanks, i.e. I.D.3.4 was based on calculation of the average of three measured values rather than a single measured value .

Reason for the deviation :
During the initial period of operation, the PP had decided to monitor the performance and efficiency of each of the digesters. Therefore, the COD was measured at the outlet of each of the digesters rather than at a common point at the outlet of the three digesters.
The POME from the mill was pumped to an overhead tank which was then fed to each of the digesters by gravity flow. Since the diameter of the pipe from the overhead tank to each of the digesters is the same and the tanks are located in close proximity to each other, the volume of flow into each of the digesters and the volume of overflow through the outlet of each of the digesters can be considered to be the same. Hence, measuring the COD at the outlet of each of the digesters and taking the average should not produce a value that is significantly different from measuring the COD value at a common point after the outlet of the digesters, as implied in the monitoring plan.

ii) Deviation no. 2 – monitoring of COD I.D.3-2, I.D.3-4, I.D. 3-5, I.D.3-18

According to the monitoring plan in the registered PDD, the monitoring of COD shall be carried out on a daily basis during the first year of operation. During the period from 1 February 2009 to 31 March 2009, PP had carried out monitoring activities only 6 days in a week. No monitoring was carried out on Sunday.

Reason for the deviation :
Sunday is an off day for the mill. During the initial period, the operators had not been instructed to collect the samples on Sunday as it is an off day and due to PP’s unfamiliarity with the CDM project requirement. However, from 1 April 2009 onwards, this omission was rectified and daily monitoring was carried out.

iii) Deviation no. 3 – monitoring of biogas Calorific Value project (monitoring I.D.3-11)

According to the monitoring plan in the registered PDD, the biogas calorific value is to be measured annually. During this monitoring period, only one measurement was carried out (on 16 December 2010). No measurement was carried out in 2009

Reason for the deviation :
The reason for the deviation was that PP had difficulty in sourcing a local accredited laboratory to carry out the test. The only accredited laboratory in Malaysia that is capable of carrying out this test is in SIRIM which is also the verifier. Eventually, a laboratory in the region was found (Intertek Testing Services (Singapore) Pte. Ltd.) and the analysis was carried out on 16 December 2010.

iv) Deviation no. 4 – method of measurement for loss of biogas from pipeline (monitoring I.D. 3-12)

According to the monitoring plan in the registered PDD (Table 8: Monitoring Parameters for Project Emissions), the method of measurement for loss of biogas from pipeline is to be tested annually through pressuring the system and establishing pressure drops through leakage.

Reason for the deviation :
The pressure test was carried out after construction and installation on 10 July 2007 i.e. prior to the operation of the plant. It is impractical to measure pressure drops annually using the method specified in the registered PDD because biogas is flowing continuously. Leak detection by using detergent solution at the welded pipe joints is an effective leak detection method and it was carried out annually.

The first three deviations (Deviation no. 1, 2 and 3) do not require revision of the monitoring plan or change from the project activity as described in the registered PDD, as all parameters were now being monitored in accordance with the monitoring plan described in the registered PDD.

A request for revision of monitoring plan will be needed for deviation no. 4 before the next verification. Since the project is newly commissioned and the results from soap bubble tests revealed no leak at all the welded joints and flanges, a request for deviation is considered adequate for this monitoring period.

Deviation no. 1 – monitoring of COD of POME leaving closed tanks digesters (monitoring I.D.3-4)
The volumes of digested POME from all 3 digesters are the same. This assumption can be proven by comparing the average value of the COD obtained from measurements at the outlet of the 3 digesters during the deviation period,with the measurements taken at a common point after the deviation period, which showed no significant variation in values. Please refer to the data attached – Appendix 1

Deviation no. 2 – monitoring of COD I.D.3-2, I.D.3-4, I.D. 3-5, I.D.3-18
The COD values from various outlets are taken as average of the measured results for the whole month. The are only 9 missing data in 2 months (i.e. on every Sunday for the month of February and March 2009), and therefore, it is considered this should not have a significant impact on the emission reductions calculation for the whole monitoring period.

Deviation no. 3 – monitoring of biogas Calorific Value project (monitoring I.D.3-11)
The project activity does not claim any emissions reduction from the generation of heat component. Therefore, this value is not in used in any of the calculation of the ER.

Deviation no. 4 – method of measurement for loss of biogas from pipeline (monitoring I.D. 3-12)
In accordance with the registered PDD, this parameter is to be included as project emissions if it is proven that the biogas leak from the pipe is more than 1% of CER. The material used in the biogas pipeline is stainless steel, and the potential for leak is at the welded joints. The current method of testing the biogas leak in the pipeline is the simplest method to detect leaks without distrupting the operation of the project. Since no leak was detected during the two tests that were conducted, it can be concluded that there was no project emission due to these losses.