In a series of themes , Greg Yeoman, designer and co-founder of Enviropod explores the 4 fundamental areas of product re-development of the modern day Enviropod LittaTrap from the development of improvements from the somewhat ‘agricultural’ folded sheetmetal filterbox and cage design from 1996 to the latest 2021 generation modular composite Enviropod LittaTrap available today.
Design – Form follows FEA
Materials – Coping with -40C - to +40C
Performance – It’s in the bag
Packaging – Less is More
At the heart of the Enviropod LittaTrap redevelopment was product performance across removal efficiency, ease of installation and ease of maintenance. After two decades of experience designing and installing Catch Basin inserts a wealth of knowledge culminated in a design with improvements across all these key areas.Removal efficiency and maintenance frequency are directly related to a couple of key factors for any catch basin insert, these being screening area and storage volume.
The bag (basket)- The larger the useable screening area and volume in the insert basket, the better the long-term performance. In order to maximise the basket volume, are evolutionary battening system was developed. Taking the lead from New Zealand's innovative yachting industry the concept of battening to hold and support the fabric basket was employed. Glass fibre battens are used as part of the patented basket system which allows a flexible mesh basket to be filled with pollutants (or stones) without the bag walls bulging, and hence can be lifted through the support frame in any state. Another learning from supplying Enviropod products for 25 years is that no two sites are the same and different customers have different needs depending on pollutant removal goals or maintenance budget or a balance between the two.
The Enviropod LittaTrap comes standard with a durable plastic mesh Gross PollutantTrap (GPT) basket which will capture all material over 5mm in size – targeting pollutants such as Litter/trash, macro-plastics and cigarette butts. By targeting larger pollutants GPT basket will have a much lower maintenance frequency, often requiring maintenance as little as once or twice a year depending on the site.
Performance can be enhanced by adding a series of custom liners to the basket. 1mm fibreglass mesh liners can be installed to target resin pellets (nurdles) from plastic manufacturing, shipping or trans load sites. A 200 micron liner can be added (Enviropod200) to capture fine sediment (TSS) or finer plastic granules and other custom liners can be manufactured for custom requirements. DesignerGreg Yeoman recounts “The move away from a filterbag bag sitting in a large metal reinforcing mesh cage to a soft mesh GPT basket meant that we could place any liner within the basket as it was continuously supported. With the previous design mesh bags were constantly tearing during maintenance due tothem bulging through the cage, but now the entire basket and liner are removed together via the ‘LIFT’ handles. Maintenance contractors are loving the fact that it is now hand maintainable and intuitive, feedback from site owners and contractors is that hand maintenance is significantly cheaper than using a vactor truck”
Health and Safety of installing and maintaining pit inserts and pipe screens can also be a costly exercise. Unlike many other technologies where a person requiring confined spaces training needs to enter the pit, in almost all cases, the new Enviropod LittaTrap can be easily and safely installed and maintained from above the ground, meaning time, cost and the associated risk of working underground are eliminated.