FR2467530A1 - PLANT FOR THE PRODUCTION OF METHANE USING LIQUID AND SIMILAR WASTE - Google Patents

Abstract

Installation for producing methane from liquefied waste from livestock feces, intended to recover energy in the form of methane gas, and comprising an anaerobic container 1 at controlled temperature with stirrers 5, in communication with a device ensuring the supply of waste and on the upper part of which is grafted a gas release pipe 12 ending in a tank 13. The residual treated waste, discharged from the container 1, lending itself to being used as fertilizer fertilizer.

Description

The present invention relates to an installation

  intended to produce methane using liquid and similar waste.

Currently great importance is given to

  problem in order to achieve energy saving, and also looking for

  che allowing to take advantage of various wastes in order to recover energy

what they contain.

  Among the wastes with a certain energy value

tick, there is in particular liquid waste containing faecal matter from livestock farming

So far, this waste has only been used for fertili-

  sation of the soil. Collected in pits or other suitable receptacles, they are left to rest for a certain time in order to make them undergo a transformation to allow them to be used as fertilizer. It has been found that in the idle state, this waste releases gases considered so far

as an inconvenience polluting the atmosphere. We never had the idea to shoot

made of these emanations, since their quantity was considered negligible.

  The object of the present invention is to provide an installation for collecting the methane contained in this waste to serve

  energy source, with a treatment that makes residues faster-

usable as fertilizer.

  According to the invention, the installation used to extract

  re methane starting from the liquid waste mentioned, is simple and of dimen-

  very reduced while presenting the guarantees of efficient operation

completely avoiding the risks of polluting the environment.

The installation according to the invention does not require

  maintenance and its operating cost is very low. In addition, it

  puts to recover a significant amount of energy, in the form of methane gas

  of biological origin. It can be easily carried out using materials

rants in trade, and is very competitive in terms of its performance.

The installation includes an anaerobic container

controlled temperature communicating with a device supplying it with waste.

  At the upper part of this container is a gas release pipe communicating with a reservoir which receives it, while in an intermediate part of the container is provided a pipe

of the treated waste.

  -2- The attached schematic drawing represents as

  non-limiting example, an embodiment of this installation.

  An anaerobic container 1 at controlled temperature is closed in a sealed manner at the top by a cover 2 forming a good thermal insulator. The container 1 communicates with a device 3 bringing the waste, which is connected to the container 1 by means of a pipe 4,

  opening at the bottom of the container 1.

  Inside the container 1 is provided an agitator l 5, preferably of the type with horizontal shaft with radial blades functioning so as to keep in continuous movement the mass of waste contained in the

  container for the purpose of promoting the chemical reaction giving off gas.

The agitator 5 is rotated about its axis

by an electric or other motor.

  At the top of container 1, and more precisely in

the insulating cover 2, there is a gas release pipe 10 communicating

  as for a bubbling tank-11 in which is contained a certain amount of water. On this bubbling tank 11 is grafted another pipe

  12 pqur the gas which ends up in a tank 13 o the gas is accumulated.

  The tank 13 is equipped with safety means which

  are normally provided for this kind of container.

  The bubbling tank 11 has the very important function

  bearing to act as a diaphragm on the junction between the reservoir 13 and the container

pient l. in order to prevent possible flashbacks or other phenomena

  dangerous nomenes that can occur.

  At an intermediate height of the container l is

  a discharge line 20 for the treated waste provided with a siphon 21,

  plugging in a collector 22. This residual treated waste which is sent there

  born can be directly used as fertilizer.

  The operation of the installation is very simple.

In fact, the faeces of the cattle, preferably those coming from cattle breeding, are brought into the container 1 o the agitator 5 keeps them in continuous movement so as to promote the release of methane from these wastes during the treatment. t ', t Then the gas is sent to the tank where

  it can be taken for the appropriate uses.

In an testing facility, an anaerobic container with a capacity of 9m3 and a filling coefficient was chosen.

from 0.85.

  The waste used was dry excrement -3- of bovids of 20% weight treated at a temperature of 250 C in a medium

having a pH = 7.

The gas collected as a result of the anaero-

bie produced in this container was at a pressure of 0.015 bars and an average daily production of 1 Dm 3 of gas was obtained. The tank re-

  however the gas had a capacity of 3m3.

  The gas obtained presented energetic characteristics.

optimal getics.

  Indeed it was found by a chemical analysis that said gas had the following composition: CH4 (methane) 57% Co2 42.5%

CG 0%

02 0%

  other gases (NI-3 and H2S) traces Joules calorific value 21.106

This result makes it possible to affirm that the treatment of ex-

  dry creatures of cattle and waste in general allows to obtain a significant production of energy in the form of methane gas thus largely justifying its

  adoption, both for domestic use and for industrial applications

trielles.

  Among the advantages, it is worth mentioning first

  better than producing a significant amount of energy and then

  considerably reduce the processing of waste from cattle farms

  dice and the like, thus making rapid and practically immediate use possible

waste as fertilizer.

  In addition, the installation requires practically no monitoring, since it can be easily automated without it arising

problems for the user.

  The invention is of course liable to modify

cations and variations with respect to the constituent technical details-

32 equivalents.

_4-

Claims (5)

  1. Installation intended to produce methane using liquefied waste, characterized in that it comprises an anaerobic container at controlled temperature, communicating with a device bringing the waste to be treated, the upper part of this container comprising a discharge pipe for gas communicating with a tank where the gas is collected, while at a height of an intermediate part of the container   a residue discharge line is connected. 2. Installation according to claim 1, character- laughing in that the container is closed at the top by a lid, made of insulating.   3. Installation according to claims 1 and 2, characterized in that inside the container is arranged an agitator of the type preferably with a horizontal shaft provided with radial blades set in rotation by a motor.   4. Installation according to one or more of the res- dications 1 to 4, characterized in that in the gas release line   is inserted- a bubbling container.   5. Installation according to one or more of the res-   above, characterized in that on the discharge line of the treated waste is provided with a siphon.