In wastewater treatment, both polyaluminium chloride and
polyacrylamide serve as effective water purification agents. Many practitioners routinely employ these two products in tandem during the treatment process. What advantages does this combination offer, and is such usage justified? Let us explore.
In conventional wastewater treatment, many practitioners predominantly employ polyaluminium chloride for water purification. Should results prove unsatisfactory, dosage is often incrementally increased. However, excessive polyaluminium chloride usage can lead to elevated suspended solids during treatment. Concurrently, an overabundance of positive charges diminishes turbidity removal efficacy. Simply put, excessive polyaluminium chloride not only fails to improve turbidity but may even have counterproductive effects, increasing operational costs. The combined use of polyaluminium chloride and polyacrylamide has gained user recognition. Polyacrylamide itself possesses strong hygroscopic properties. When used in conjunction with polyaluminium chloride, it effectively improves water quality to achieve wastewater treatment objectives, presenting a favourable option.
During water treatment, certain wastewater streams prove difficult to treat satisfactorily using a single coagulant alone. Employing polyacrylamide alongside polyaluminium chloride can ameliorate wastewater issues. However, polyaluminium chloride functions as a coagulant, requiring only brief reaction time with wastewater during treatment. Thorough and vigorous mixing is essential after its addition to water. Polyacrylamide, conversely, functions as a flocculant. During mixing, agitation must not be excessively vigorous to prevent disruption of the formed flocs. Typically, when employing both polyaluminium chloride and polyacrylamide products, polyaluminium chloride should be added first, followed by polyacrylamide. Nevertheless, for safety, it is advisable to conduct trials to determine the optimal dosing sequence. Questions regarding brief interval times, dosage quantities, and proportion ratios can be definitively resolved through rigorous scientific testing. It is crucial to note that polyaluminium chloride and polyacrylamide products must never be mixed together for combined use. Similarly, products from different manufacturers should not be used together. This practice not only directly compromises wastewater treatment efficacy but also increases operational costs.
