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041, e • O Design Design Basis To ensure that the system is designed properly for a given application,it is critical to first determine the design basis.The design basis for any treatment system consists of careful evaluation of several parameters that control the system's design and subsequent performance.Orenco's"Engineered Project Questionnaire,"NFO-ATX-ADM-2,is available to assist in identifying and characterizing these parameters.It can be downloaded from Orenco's Document Library at www.orenco.com,or you may contact Orenco or your local Orenco Dealer for a copy.This document provides a list of the typical design param- eters necessary to determine the suitability of Orenco products to a given project and for forming the system's design basis. Average Day and Maximum Day Flows Flows may be defined or calculated differently by application and local regulation; however,as used in this document: Design Average Flow(QA)is the average of the daily volume to be received for a continuous 12-month period expressed as a volume per day.For facilities having critical seasonal high hydraulic loading periods(e.g.,recreational areas,campgrounds)the design average is based on the daily aver- age flow during the seasonal period. Design Maximum Day Flow(QM)is the largest volume of flow to be received during a continuous 24-hour period expressed as a volume per day. The Design Maximum Day Flow is highly dependent on the application and collection technology used.For Effluent Sewer(STEP),Grinder Sewer,and Vacuum Sewer,a typical value is two times the Design Average Flow(20A). For Conventional Gravity Sewer applications,a typical value for QM is four times the Design Average Flow(40A)for new construction and can range to over ten times(10QA±)for existing systems.Make sure to carefully evaluate any existing flow information and regulatory requirements when estab- lishing this design parameter. Primary-Treated Effluent Wastewater Strength Organic Constituents in Wastewater The two primary organic constituents in wastewater used in determining applicability and sizing of AdvanTex Treatment Systems are biochemical oxygen demand(BOD and total suspended solids(TSS).These constituents are typically quantified either in raw wastewater or after the primary treatment stage.In order to determine the waste load to the AdvanTex Treatment System,it is necessary to determine the constituent concentrations after primary treatment.These constituent concentrations are referred to as primary-treated effluent throughout this document,and all percent reduction estimates are calculated relative to these concentrations.If these constituents are provided as raw wastewater values,it is the responsibility of the designer to determine the appropriate primary treatment requirements to achieve the primary-treated effluent values used in the design.Industry experts typically estimate that appropriate primary treatment(see Appendix A for primary tank sizing recommendations)will provide 50%reduction of BODS(down to a minimum of 150 mg/L)and 90%reduction of TSS(down to a minimum of 50 mg/L). Nitrogen Constituents in Wastewater The principal forms of nitrogen found in wastewater are Organic Nitrogen (Organic-N),Ammonia Nitrogen (NH3 N),Ammonium Nitrogen (NH4 N), Nitrite Nitrogen (NO2 N),and Nitrate Nitrogen (NO3 N).These are expressed either individually or as components of the following: • Total Kjeldahl Nitrogen (TKN),which is the sum of Organic-N+ NH3-N • Total Inorganic Nitrogen (TIN),which is the sum of NH3-N + NO2-N +NO3-N • Total Nitrogen (TN),which is the sum of TKN+ NO2-N +NO3-N As with the organic constituent concentrations,the nitrogen constituent concentrations must be quantified after the primary treatment stage to determine waste load to the AdvanTex Treatment System and are listed as primary-treated effluent throughout this document.A thorough under- standing of the nitrogen cycle and how it works within the wastewater system is important when designing a system to treat for these parameters. A brief description of the processes follows: Ammonification Nitrogen is usually introduced into the wastewater system as Organic-N and NH4-N.Organic-N(including feces,urea,and other animal and vegetable matter) in wastewater is converted into NH4-N by the process of ammonification.In ammonification,proteins,amino acids,and other nitrogen-containing compounds are biochemically degraded by heterotrophic bacteria.Ammonification typically occurs in primary tankage and trans- port lines,as well as in the secondary treatment process.Because of this,a raw wastewater ammonia measurement may be significantly lower than the true value. In these instances,TKN is a better measure of overall nitrogen content and should be used when determining waste load to the AdvanTex Treatment System. NDA-ATX-1 Orenco Systems®•800-348-9843•+1 541-459-4449•www.orenco.com Rev.8,©10/20 Page 6 of 38