Reducing Over-consumption of Acid during Skim Latex Coagulation in Cameroon’s Rubber Processing Factories

  • Louden Motina Institute of agricultural research for development, Batoke, 77 Limbe, Cameroon
  • Ambe Rex Vrije Universiteit of Brussels, Boulevard de la Plaine 2, 1050 Brussels, Belgium
Keywords: Skim latex, coagulation, acid overconsumption, rubber processing


Latex processing factories in Cameroon transform field latex to latex concentrate and skim latex is generated alongside, being poor in dry rubber content and high ammonia content, it is mostly coagulated as skim rubber, for use in rubber products. These factories face enormous problems with the overconsumption of acid during skim coagulation, which results to extra expenses and high acidic waste water production problems. Therefore the is a need to reduce the overconsumption of acid during skim coagulation. In order to solve this problem we started by identifying all possible causes of acid overconsumption at the factory using the ISHIKAWA diagram. We further hierarchized these causes using a Pareto diagram and sought out 3 main causes of great impact to be addressed which are: the low performance of the deammoniation process; poor practice of coagulation; negligence. We proposed solutions by optimising the deammoniation process at the tower i.e. controlling its skim and air flow rate inside the deammoniation tower to optimal values. Also we determine the optimal volume of acid needed for effective coagulation which when applied reduces acid consumption. Lastly we optimized by proposing a new mode of operations for the coagulation process. By implementing this new approach, we recorded an estimated total acid reduction of 28,924 L/month (347088L/ year) and this will enable the company to save money about 770,469 FCFA/month (21,245,639 FCFA/year). This approach can be adapted in any other rubber processing unit and will reduce acid overconsumption during skim latex coagulation.


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