Selection look-up charts.
Seven tables we work from. Most cover wastewater plant sizing; the newest covers incinerator emissions and process parameters. Every figure carries its evidence level: a national standard clause, a national standard table value, an official guide, an industry statistic, or a vendor-published figure.
How strong is each figure?
A number is only useful if you know where it comes from. Every chart states its evidence level, and the five levels are defined here.
- National standard clause
- A requirement or a calculation method set out in a national standard (GB 50014-2021, GB 50013-2018).
- National standard table value
- A numeric value taken directly from a table inside a national standard, for example GB 50014-2021 Table 4.1.15 or GB 18918-2002 Table 1.
- Official guide
- A value from an official or industry-authoritative design guide rather than a mandatory standard — British Water, US EPA or Saudi MEWA.
- Industry statistics
- A figure from operational statistics. It describes what plants actually receive or consume. It is not a standard value and must not be presented as one.
- Vendor-published figure
- A figure published in an equipment catalogue. It is used only for comparison between ranges; it carries no industry-wide validity.
The seven charts
Population to capacity
Per-capita allowances and the combined domestic sewage allowance rule, with UK, US and Middle East export figures.
Peaking factor Kz
The flow variation factor by average daily flow, and how the 2021 edition differs from the superseded 2006 values.
Container loading
Internal dimensions, volume and payload of 20GP, 40GP and 40HC containers, plus the width and height limits of a standard dry container.
Influent quality
COD, BOD₅, SS, NH₃-N, TN and TP — national statistical means, the 80th percentile and common design ranges.
Effluent standards to process train
GB 18918-2002 Grade 1A, Grade 1B and Grade 2 limits, with the process train that usually delivers each target.
Tank volume and HRT
Anaerobic and anoxic tank HRT, solids retention time for phosphorus removal, the tank volume formula and the Middle East extended-aeration range.
Incinerator emissions and process parameters
Combustion parameters published for incinerators, and the GB 18484-2020, GB 39707-2020 and GB 18485-2014 flue-gas emission limits for medical, hazardous and municipal solid waste.
How to use the charts together
- 1Start from population or flow. Use the population to capacity chart to fix the average daily flow, or take the design flow from the project brief.
- 2Apply the peaking factor. Multiply the average daily flow by Kz to get the peak flow. Tanks and pipes are sized on the peak, not on the average.
- 3Check the influent load. Use the influent quality chart to see whether the organic load is within the range the process can take; high-strength wastewater is often governed by the organic load rather than the flow.
- 4Pick the process train from the effluent standard. Move from the discharge grade to the process combination that delivers it, then size the tanks.
- 5Size the tanks. Use the tank volume chart with V = Q × HRT to turn the process train into volumes, and check the solids retention time against the phosphorus removal target.
- 6Convert to containers for shipment. Use the container loading chart to check whether the assembled unit fits a standard dry container, and how many units or partial shipments the site will take.
Charts pending factory data
Two draft tables in the wastewater plant set are not published yet, and they are the only drafted charts still held back. Both are withheld because the underlying numbers are not confirmed.
Integrated equipment capacity bands (3 / 5 / 10 / 20 / 30 / 50 / 100 / 200 m³/day)
Factory data pending. There is no industry-wide band table, and no national standard maps a flow rate to a footprint or a weight, so the band table is not published here.
Energy and chemical consumption
Factory data pending. The available figures are industry aggregates with no standard source, so the chart is being restructured into influencing factors and an estimation method rather than absolute values.
Both tables stay marked [to be confirmed with factory] until the factory data are supplied.