Build a sludge identity record
Identify primary, waste-activated, digested, mixed or industrial sludge. Include blend ratio, storage time, feed dry solids and any upstream chemical change. Preserve the sample’s fine fraction and avoid comparing material collected from different feed conditions.
Treat a change in digestion or industrial contribution as a reason to recheck the operating range. Increasing product dose without identifying a solids-loading change can hide the real cause of poor capture.
Match the test to the machine
For a belt press, observe free drainage, distribution, side losses and cake release. For a screw press, include filtrate quality, loading and discharge behavior. For a centrifuge, compare centrate, cake and throughput while recording relevant machine settings.
A jar or drainage test narrows the sample set; it does not reproduce every mechanical stress in a full-scale separator. Confirm the finalist during a controlled plant run, allowing sufficient process residence before collecting results.
Report both streams and the dose basis
Record cake solids and return-liquor suspended solids together. A drier cake is not an improvement if solids losses increase beyond the plant’s acceptance condition. Compare commercial consumption per dry tonne, not only solution pump speed.
Use the dry-solids dose calculation and wet-cake troubleshooting sequence when bench performance and production disagree.