The biocarrier escape routes Identifying leaks through a Product Chain Organisational study

Abstract

Biocarriers used in the Moving Bed Bioreactor process serve a good operational purpose, cleaning wastewater that would otherwise pollute the ocean without using toxic chemicals. But, incidents occur when biocarriers escape from the process and leak into the sea. The good purpose is lost, and the carriers become harmful marine plastic waste. These process leakages are within human and natures best interest to prevent, which means taking full responsibility for an extended length of the prod- uct’s life cycle. The biocarriers are suspended HDPE/PE plastic objects for housing and protecting microbes separating wastewater from nitrogen compounds. Applied in thousand or millions into the wastewater processes for municipal and industrial purposes, they add surface for the microbes to more efficiently treat wastewater and comply well with capacity and seasonal changes. Complication of biocarrier leakages is the added environmental impact from plastic pollution, including micro- and nano-plastics as carriers break down to smaller particles when exposed to wear and UV-light. Production, system installation, operation and waste management are the four phases in the life cycle approached in this thesis. The actors for each phase are identified to build the understanding of the Product Chain Organisation (PCO) of biocarriers. The PCO study method visualises interconnections, actor influences, system failures and possible sustainable system changes to detect, support and de- velop measures and strategies for better management of biocarrier processes with a mitigated impact from leakages. Quantification of the problem remains deficient due to non-specific categorisation in beach litter monitoring. Experiences and witnesses from beach litter actors along with estimations in data collected describes this litter as abundant across the north-east Atlantic coastal areas. To prevent and reduce biocarrier leakages, three levels of recommendation is con- cluded by the project. The first is the internalisation of externalises by the process owners given by additional barriers assigned for leak prevention. The second is surveillance and permit approval to increase system requirements from regional reg- ulators. The third is higher instances of regulators and international collaborations to regulate this type of marine plastic pollution and make additions in required risk assessments to specify biocarrier leaks.