**4. Conclusions**

 The results obtained revealed that the combined system (AH+ PTF) is very effective for the treatment of tomato industry wastewater at a total HRT not exceeding 10 h. The total process removed 96% of COD total, 92% of COD soluble, 98% of COD particulate, 85% of TKj-N, 89% of NH4 –N, 97% of TSS, and 98% of VSS. The effluent quality is complying for reuse and /or discharge according to Egyptian standards for discharge.

Polyurethane Trickling Filter in Combination with

Anaerobic Hybrid Reactor for Treatment of Tomato Industry Wastewater 377

Dissolved oxygen: DO

gCOD removed: gCOD R Sludge residence time: SRT

Polyvinyl chloride: PVC

Percentage removal: %R Volatile fatty acids: VFAs

**5. References** 

383–392.

Total nitrogen: TN

Total Kjeldahl nitrogen: (TKj-N), Thermal conductivity detector: TCD

Mixed liquor suspended solids: MLSS

Influent wastewater: Influent WW anaerobic hybrid effluent: AH-eff.

Influent expression: Inflow wastewater Effluent expression: Treated wastewater Anaerobic hybrid effluent: AH-eff

Scanning electron microscope:SEM Flame ionization detector: FID NOx-N: NO3-N + NO2-N

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Mixed liquor volatile suspended solids: MLVSS

 The experimental results obtained here demonstrated that AHreactor and PTF was capable of operating efficiently at short HRT and high values of OLR in the treatment of tomato industry wastewater. Therefore, the volume of the reactor could be reduced five times in comparison with that used in conventional treatment systems without affecting the organic matter removal and nitrification efficiency.
