GB2557310A

GB2557310A - Method of producing energy from animal waste

Info

Publication number: GB2557310A
Application number: GB1620707.8A
Authority: GB
Inventors: Dalgliesh John
Original assignee: Individual
Current assignee: Individual
Priority date: 2016-12-06
Filing date: 2016-12-06
Publication date: 2018-06-20
Also published as: GB201620707D0

Abstract

A method of generating energy from animal waste comprises taking animal or human waste to power plant 2 to be transferred into silos 4. The silos 4 comprise agitators 6 which churn the waste to produce gas which fills flexi-domes 8. Gas is then fed through piping system 10 to drive combustion free gas turbines 12 to generate electricity which is sent to the power grid 14. The spent gas which is generally methane is then bottled in a bottling plant to be sold. The solid waste is then dried and burned to produce electricity.

Description

(54) Title of the Invention: Method of producing energy from animal waste Abstract Title: Method of producing energy from animal waste (57) A method of generating energy from animal waste comprises taking animal or human waste to power plant 2 to be transferred into silos 4. The silos 4 comprise agitators 6 which churn the waste to produce gas which fills flexidomes 8. Gas is then fed through piping system 10 to drive combustion free gas turbines 12 to generate electricity which is sent to the power grid 14. The spent gas which is generally methane is then bottled in a bottling plant to be sold. The solid waste is then dried and burned to produce electricity.

1/1 /Χ

Method of Producing Energy from. Animal Waste

The present .invention relates to a method of producing energy 5 from animal waste and relates particularly, but not exclusively to a method of producing electricity from both the gas and solid material in human waste. The present invention also relates to an apparatus for producing energy from animal waste.

Power plants are known which burn biomass to generate electricity, Most are either wood fuelled or run off animal waste such as slurry. When animal waste is used, the remaining solid material is generally reprocessed to provide fertiliser.

Agricultural biomass power generation suffers from the drawback that additives generally have to be put into the fuel such that the fuel being used is not 100% waste. Also, the remaining solid material from the process then generally has to be reprocessed as fertiliser,

Wood biomass plants suffer from the drawback that woodland has to be destroyed to provide the fuel.

Preferred embodiments of the present invention seek to overcome the above disadvantages of the prior art,

According to an aspect of the present invention, there is 30 provided a method of producing energy from animal waste, the method comprising:

processing animal waste in an agitator to separate gas from the animal waste and form solid waste;

under supplying the gas under pressure to drive a first turbine to generate elec t r i c i t y;

drying the solid waste to produce solid fuel;

burning the solid, fuel to drive a second turbine to generate electricity.

This provides the advantage that, not only the gas (generally methane) produced from animal waste, but also the solid material is used in a two-stage process to efficiently generate electricity.

The method may further comprise pressuring flexi-doraes with separated gas to store the gas at pressure prior to supplying the gas under pressure to drive said first turbine.

The method may further comprise bottling gas used to drive said first turbine.

This provides the advantage of providing a third source of energy from the process.

The method may further comprise supplying heat energygenerated by burning the solid fuel to dry solid waste.

This provides the advantage of improving the efficiency of

--· }·, £0, ry γ'ί-'ν γ“Ό co in a preferred embodiment, wherein the animal waste used is human waste.

-3In some countries, it is generally not allowable to use human waste for fertiliser on land. This method therefore provides the advantage of a process which has minimal leftover byproducts of the power generation,

This method also provide the advantage that methane produced from humans is more potent and therefore more valuable than that, produced b other animals such as pigs,

According to another aspect of the present invention, there is provided an apparatus for producing energy from animal waste, the apparatus comprising:

at least one silo comprising an agitator to separate gas from the animal waste and form solid waste;

a first turbine to generate electricity from gas separated in the silo;

a drying chamber for drying the solid waste to produce solid fuel;

an incinerator for burning the solid fuel to drive a second turbine to generate electricity.

This provides the advantage that not only the gas (generally methane) produced from animal waste, but also the solid material is used in a two-stage process to efficiently generate electricity.

'in some countries, it is generally not allowable to use human waste for fertiliser on land. This method therefore provides

-4· the advantage of a process which products of the power generation

Said at least one silo comprises has minimal leftover bywhen human 'waste is used, a flexi-dome for storing gas under pressure.

The apparatus may further comprise a heat exchanger for transferring heat from the incinerator to the drying chamber.

This provides the advantage of improving the efficiency of the process.

A preferred embodiment of the present invention will now be described,, by way of example only and not in any limitative sense, with reference to the accompanying drawings in which:

Figure 1 is a schematic of a method and apparatus for producing energy from human waste.

Animal waste (excrement) which in a preferred embodiment is human waste sourced from portable toilets, is taken to power plant 2 and transferred into at least one silo 4. in the embodiment shown, three silos are used. The silos 4 comprise agitators 6 which churn the human waste to produce gas which fills flexi-domes 8,

Flexi-domes are pressurised balloons which store and maintain the gas at pressure. Gas is then fed through piping system 10 to drive combustion free gas turbines 12 to generate electricity which is sent to the power arid 14, The spent gas which is generally methane is then bottled in a bottling plant to be sold.

Solid waste left over in the silos is pumped to a drying station 16 and heated to dry the solid waste and provide solid fuel. Solid fuel is then burnt in incinerator 18 to provide heat to drive a second turbine 20 to produce further electricity for the power grid 14. Heat from incinerator 18 is redirected into drying station 16 via a heat exchanger to increase the efficiency of the process,

It will be appreciated by persons skilled in the art that the 10 above embodiment has been described by way of example only and not in any limitative sense and that various alterations and modifications are possible without departure from the scope of the invention as defined by the appended claims. For example, animal waste rather than human waste can be used.

Claims

1. A method of producing energy from animal waste, the method comp rising:

supplying the gas under pressure to drive a first turbine to

10 generate electricity;

drying the solid waste to produce solid fuel;

burning the solid fuel to drive a second turbine to generate

15 electricity.

2. A method according to claim 1, further comprising pressuring flexi-domes with separated gas to store the gas at pressure prior to supplying the gas under pressure to drive

20 said first turbine.

3. A method according to claim 1 or 2f further comprising bottling gas used to drive said first turbine.

25

4. A method according to any one of the preceding claims, further comprising supplying heat energy generated by burning the solid fuel· to dry solid waste.

5. A method according to any one of the preceding claims,

30 wherein the animal waste used is human waste.

6. An apparatus for producing energy from animal waste, the app a ratas camprising:

from

-7at least one silo comprising an agitator to separate gas the animal waste and form solid waste;

5 a first turbine to generate electricity from gas separated in the silo;

a drying chamber for drying the solid waste to produce solid fuel;

7. An apparatus according to claim 6, wherein said at

15 least one silo comprises a flexi-dome for storing gas under pressure.

8. An apparatus according to claim 6 or Ί, further comprising a heat exchanger for transferring heat, from the

20 incinerator to the drying chamber.

Intellectual

Property

Office

Application No: GB 1620707.8 Examiner: Mr Martin Price