waste water system
DESCRIPTION
Group 4 project onTRANSCRIPT
Why would you pay for heat only to let it go down the drain?
Drain-Water Heat Recovery
• Whether washing clothes by hand or letting the machine do the work, the water going down the drain contains a lot of heat energy.
• For homeowners, this wasted heat energy costs several thousands kroner per year.
• For a business (school), it can add up to more than tens of thousands of kroner.
OUR PROPOSAL
• To implement “Drain-water heat recovery” in Uncle Tom’s Cabin, using the hot water used by the washing machines.
How does it work?
• Drain water flows through a spiral tube; this warms the tank water, which rises to the top. Water heater takes preheated water by circulation through a coil at the top of the tank.
Benefits
• Saves up to 40% on water heating costs!*• Maintenance-free and has no moving parts to
break down.• Is environmentally friendly, reducing the
energy consumption by five to 10%.• Reduces greenhouse-gas emissions.
• * Heat-Recovery Water heating http://gfxtechnology.com/HR3-7-1.PDF
Data
• After sampling 15 out of 200 students the results show that an average of 1.13 washes per person each week are done 200*1.13=226.6 washes per week.
• The washing machine takes 0.25 kWh per kilogram of clothes. An aproximation of 5-7 kilograms are washed each time0.25*5=1.25 kWh 0.25*7=1.75 kWh
• For 230 washes between 287.5-402.5 kWh are used.
• The cost of each 1kWh is 0.50 kr:287.5 kWh (0.50)=143.75 kr402.5 kWh (0.50)= 201.25 kr
• Assuming that the machines are used 9 months each year:– 5545kr – 7765kr
• According to investigations this system can save up to 40% of the costs. – 5545kr saving 40% =2218kr.– 7765kr saving 40% =3106kr.
FINANCIAL ISSUES
• Costso Between 2145 and 3580 kroner per system.oWith the saving of 2218kr-3106kr the investment
would be recovered in one year.
CONCLUSION
• If the system is applied:– The college will save money (3000 kr per year,
after the first year), and energy will be recycled. – It would contribute to our goal of an eco-village.
ALTERNATIVE OPTION
• If for certain reasons the system can’t be applied in Uncle Tom’s Cabin, we recommend the College to use it in the new Leirskule building as a general system. It would be minimize the waste of energy through dissipated heat.