The specific characteristics of sewage generated by the PWC parking areas (a lot of urine and a high proportion of toilet paper and coarse particles in the sewage), the cause of this (user behaviour, water saving sanitation facilities) and the consequences (disturbances of operation by clogging, difficulties in biological treatment and sludge removal) require adapted concepts and technologies for the economical and safe operation of wastewater disposal. Based on the findings of the research project FE 02.202 / 2000 / MRB, the design and implementation of the wastewater treatment system of the PWC Jalmer Moor at the BAB A7 was scientifically supported and the concept and the operation were evaluated. On the one hand, attention was focused on the effective retention of solids in a primary clarifier, which is particularly important for the operational safety of sand filters. On the other hand, the separation of male urine from the wastewater mixture was investigated as a possible option for stabilizing the purification process. In the project, it was possible to derive constructive recommendations for the settling tanks of PWC plants and to show that curved screens as an alternative to settling tanks are not suitable due to operational problems. The investigations on urine separation showed that separation could make a significant contribution to the safeguarding of effluent limits and in particular to the stabilization of nitrification in the soil filter. Urine separation alone is not a guarantor for compliance with limit values. Important is the proper operation of the entire system, which requires a firm specialist and therefore should preferably be handed over to a suitable institution / company. Day-to-day inspections, such as would normally be required by trained or educated staff, cannot be dispensed with. The time required for this can only be limited by a suitable structural design of the plant. The design of future plants must take into account the interests of the subsequent operator. (Author/publisher)
Samenvatting