Creating Mini Wastewater Treatment Plants
Student teams design and then create small-size models of working filter systems to simulate multi-stage wastewater treatment plants. Drawing from assorted provided materials (gravel, pebbles, sand, activated charcoal, algae, coffee filters, cloth) and staying within a (hypothetical) budget, teams create filter systems within 2-liter plastic bottles to clean the teacher-made simulated wastewater (soap, oil, sand, fertilizer, coffee grounds, beads). They aim to remove the water contaminants while reclaiming the waste material as valuable resources. They design and build the filtering systems, redesigning for improvement, and then measuring and comparing results (across teams): reclaimed quantities, water quality tests, costs, experiences and best practices. They conduct common water quality tests (such as turbidity, pH, etc., as determined by the teacher) to check the water quality before and after treatment.
A student design for a wastewater treatment plant model.Copyright 2017 SHIFTED RET Program, University of Kansas Lawrence and Greenbush
Environmental engineers design wastewater treatment plants to clean water before discharging into rivers, streams, lakes and seas. They use a variety of stages and processes to remove solids and contaminants from wastewater, including biological and mechanical processes. Filters and settling are common mechanical processes used to remove large particles from raw wastewater. The removal of plastic from a water source is a new challenge for engineers, given the fact that plastic is not soluble nor magnetic and varies in its size and decomposition state.
After this activity, students should be able to:
- Develop and test a model for an innovative and efficient water filtration system, and recover resources.
- Conduct water quality tests.
- Provide qualitative and quantitative results that describe the success (or failure) of a model filtering system in meeting the project objectives.
- Understand the steps of the engineering design process.