Odour control at Pesticide Facilities: Eliminating volatile compounds
Chemical formulation plants are susceptible to emissions of unpleasant and malodorous volatile compounds, a fact which makes the implementation of efficient odour control measures essential.
North-western Spain is home to one of the country's oldest industrial sites for the manufacture of phytosanitary products, with some facilities located relatively close to populated areas.
Recently, the facility dedicated to the formulation of solid-state pesticides underwent a total modernisation and automation of the manufacture process, applying measures for maximum safety and minimum human contact.
For regulatory and security reasons, the formulation includes some malodorous volatile compounds with very low odour detection thresholds.
Additionally, once the product is packaged, contains a very small quantity of fine particles. For this reason, the last stage of the process involves a fluidized bed to eliminate dust, which is situated just before the packaging machine.
This fluidized bed for the elimination of fine particles causes a fairly elevated air flow (6000 Nm3/h), thus causing some unpleasant odour particles to be emitted into the surrounding environment. As the bed is open to the outside, it causes occupational health concerns in the workplace and, in some cases, complaints about the unpleasant odours from residents living near the facility.
Bioconservacion was contacted by the manufacturers of the fluidized bed equipment in order to find a solution for treating the bad smells.
Tests were carried out at the Bioconservacion laboratory in which the conditions of the fluidized bed process for eliminating fine particles were reproduced on a smaller scale. To do this, the end client, in accordance with the confidentiality terms agreed, provided the data and reagents required to reproduce the problem.
Under these conditions, several of Bioconservacion's filter media were tested. Using the data from the pilot tests in the laboratory, the engineering department at Bioconservacion was able to find an all-round solution for optimum odour control
The recommended filtration equipment, due to the relatively high flow to treat and the need to avoid affecting the existing process, was a SAH system (a modular filter unit with lateral access) with PP18 modules. The V-shaped PP18 modules provide for an optimal solution in terms of equipment size, minimal load loss and elimination efficiency.
Furthermore, the whole unit is situated at floor level, with side doors that allow for quick changes and for the used modules to be handled safely.
Upon analysis of the data from the filter media tested at the pilot plant, the use of the Bi-On+AC activated carbon filter medium was recommended. It is specifically designed for the elimination of high molecular weight compounds.
Once the solution is implemented, Bioconservacion guarantees the proper functioning of the filtration equipment and the optimisation of the filter media. At regular intervals, the client takes representative samples from the different filters and sends them to the Bioconservacion laboratory for analysis of the degree of saturation of the filter media. Bioconservacion then advises the client with regards to changing the filter at the correct time, with reasonable advance notice before the filter media become saturated, in order to avoid problems with bad odours.