Perancangan Rotating Biological Contactor dalam Pengolahan Air Limbah Peternakan Sapi

Abstract

Air limbah peternakan sapi mengandung senyawa nitrogen, khususnya NH3-N yang berpotensi mencemari badan air apabila tidak diolah dengan baik. Penelitian bertujuan merancang dan mengevaluasi kinerja Rotating Biological Contactor (RBC) dalam pengolahan air limbah peternakan sapi berdasarkan aktivitas mikroorganisme dalam memanfaatkan nitrogen. Prototipe RBC dioperasikan dengan variasi kecepatan putaran cakram 2 rpm dan 5 rpm selama 24 jam. Evaluasi kinerja dilakukan berdasarkan parameter NH3-N, dissolved oxygen (DO), pH, suhu, dan Sludge Volume Index (SVI). Hasil penelitian menunjukkan bahwa rancangan RBC mampu menciptakan kondisi yang mendukung aktivitas mikroorganisme, ditunjukkan oleh nilai DO 0,7–2,4 mg/L, pH 7,17–8,28, suhu 24,7–28°C, serta nilai SVI yang menunjukkan karakteristik sistem attached growth. Kondisi tersebut mendukung penurunan NH3-N dengan efisiensi tertinggi sebesar 72% pada variasi 2 rpm dan 55% pada variasi 5 rpm. Kecepatan 2 rpm merupakan kondisi operasi terbaik karena mampu mempertahankan kestabilan biofilm dan mendukung aktivitas mikroorganisme dalam pengolahan air limbah peternakan sapi.

Cattle wastewater contains nitrogen compounds, particularly ammonia nitrogen (NH3-N), which have the potential to pollute receiving water bodies if not properly treated. This study aimed to design and evaluate the performance of a Rotating Biological Contactor (RBC) for cattle wastewater treatment based on microbial activity in nitrogen utilization. The RBC prototype was operated at disc rotational speeds of 2 rpm and 5 rpm for 24 hours. The performance evaluation was conducted using ammonia nitrogen (NH3-N), dissolved oxygen (DO), pH, temperature, and Sludge Volume Index (SVI) as evaluation parameters. The results showed that the RBC design was able to create environmental conditions that supported microbial activity, as indicated by DO values of 0.7–2.4 mg/L, pH values of 7.17–8.28, temperatures ranging from 24.7 to 28°C, and SVI values indicating the characteristics of an attached-growth system. These conditions supported NH3-N removal, with the highest removal efficiency of 72% at 2 rpm and 55% at 5 rpm. The 2 rpm rotational speed provided the best operating condition by maintaining biofilm stability and supporting microbial activity during cattle wastewater treatment.