2022 Sasol Sustainability Report - Book - Page 56
SUSTAINABILITY PERFORMANCE AGAINST OUR FOCUS AREAS
INTRODUCTION
DATA AND ASSURANCE
MANAGING OUR ENVIRONMENTAL FOOTPRINT (CONTINUED)
Air quality management (continued)
WHAT WE ARE DOING (CONTINUED)
Air quality offset programme
Air quality abatement achievement: Towards 2025
PHASE ONE COMPLETED FOR SECUNDA, SASOLBURG AND NATREF
PMs, NOx, SO2, VOCS AND INCINERATION
In Secunda, we remain committed to implementing the second phase of our offsetting implementation plan.
This includes an environmental air quality education and awareness programme to be conducted with
7 600 households in the eMbalenhle and Lebohang communities through a door-to-door campaign. More
than 27 000 learners from 26 primary schools in Govan Mbeki Municipality and almost 11 000 learners from
nine secondary schools will participate in the campaign. The scope has been expanded to include education
and awareness campaigns on veld fire management and prevention. Communities will be informed about best
practices on separation, sorting and recycling of waste as opposed to burning, with recyclable waste collected
and taken to a buy back centre by households.
We are on track with our air quality compliance roadmaps to achieve compliance with the new plant
standards in 2025:
• Installation of low NOx burners on the remaining coal-fired boilers in Secunda and Sasolburg Operations
aimed at reducing boiler NOx emissions.
• Installation of high-frequency controllers on the electrostatic precipitators of the remaining boilers
in Secunda and Sasolburg.
• Installation of abatement equipment at the Synfuels catalytic cracker stack within SO.
• Implementing Natref’s low pressure sour gas recovery project to address SO2 emissions at the vacuum
pre-flash off-gas furnace.
In Sasolburg, the offset programme focused on the removal of waste in the areas where waste skips have been
placed by Sasol. The focus on sustainability remains by ensuring the local municipality is in a position to take
over the project post the 2025 implementation period. Challenges with heavy rain and skip servicing have been
overcome with weekly servicing of the skips now taking place. This project removed over 3 700 tons of waste
which would otherwise have been set alight. In addition to an improvement in ambient air quality, this initiative
has contributed to a vast improvement in the aesthetics of the area and the general uplifting of the people
living around the skips. In addition to waste removal, Sasolburg has cut 2,6 million m² of grass, to reduce the
impact of veld fires on the area.
• Installation of the carbon monoxide boiler upgrade for PM reduction at Natref.
• Natref sulphur recovery unit availability improvement projects are in progress.
• Streamlining of Sasolburg Operations’ blending facilities to meet the SO2 standard.
• Installation of VOC abatement equipment at the crude tar tanks within SO.
• Reduction of hydrocarbon releases from our phenosolvan and depitcher vents.
• Abatement of hydrocarbon release to atmosphere via the coal tar filtration west stack at Secunda.
The initial offset programme included Sasol’s sponsorship of emergency vehicles to the local government.
Since then, Sasolburg Operations have monitored the response of these vehicles and found numerous instances
in which they have had a positive impact in responding to fires and even vehicle accidents. For the new financial
year, the offset programme will focus on re-instating the vehicle emission testing programme and expanding
in-person education and awareness sessions.
• Finalising the routing of the biosludge from incineration to gasification.
• Confirming the sustainable alternative method to incineration for the handling of the Sasolburg
waste streams.
PERFORMANCE
Biosludge to gasification
Atmospheric emissions kilotons (kt)
Biosludge at SO is produced from a biological water treatment process and is currently
being incinerated.
The commercial-scale test run proves the technical feasibility of
extending the use of our existing gasifiers. This will enable SO
in moving away from operating four biosludge incinerators and
reducing point source emissions. The picture alongside indicates
the lysis skid deployed for thermal lysing and the lysed sludge
tank in front of the gasifier.
FEATURE STORY
To move up the waste hierarchy and simultaneously improve
ambient air quality, we have investigated co-feeding our
biosludge to our gasification process at SO to move away from
incineration and, at the same time, derive syngas from biosludge.
During the past year our investigation applied thermal lysis
innovatively to reduce the biosludge viscosity and to destroy
pathogens, and successfully completed a commercial scale pilot
of co-feeding biosludge to the existing gasification plant.
PM
NOx
SASOL SUSTAINABILITY REPORT 2022
2022
2021
8,2
119
8,2
124
SOx
162
181
VOC
26,3
27,8
Increase
Decrease
• Although additional PM abatement was installed at our boilers in 2022, due to various
challenges and inefficiencies experienced during the year, PM emissions remained at
2021 levels. However, these emissions were still substantially lower than 2020 levels
attributing to the abatement installations.
• A decrease in NOx emissions due to the installation of an additional low NOx burner.
• Numerous factors, including lower steam production, boiler availability and a reduction
in sulphur in our coal has attributed a SO2 reduction for 2022.
• The VOC emissions decreased due to increased availability of our regenerative
thermal oxiders.
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