RU2408666C2 - Method for continuous production of biodiesel fuel and apparatus for realising said method - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: apparatus has a continuous-type reactor, alcohol and raw material reservoirs, high pressure pumps, a vacuum pump, a cooler and a holding vessel. The apparatus is also fitted with a heat exchanger inside the raw material reservoir, a gravity-dynamic separator connected to the holding vessel, pressure regulators inside the alcohol reservoir and the holding vessel, as well as a pre-heating line which connects the outlet of the reactor to the pressure regulator inside the alcohol reservoir. The vacuum pump and cooler are on the same line and are connected in series. The method involves feeding alcohol and raw material into the reactor, feeding reaction products into the holding vessel, condensation in the cooler and sucking alcohol vapour using the vacuum pump. The reactor is preheated and alcohol is fed at pressure P=(1-8)P_cr and temperature T=(1-1.8)T_cr. The raw material is heated in the heat exchanger using heat from the reaction product. Alcohol vapour is condensed and sucked simultaneously and the reaction product is separated in the gravity-dynamic separator.

EFFECT: invention simplifies the scheme for producing biodiesel fuel, reduces power consumption and duration of the process.

2 cl, 1 dwg

Description

The invention relates to the field of fuel energy and for the preparation of biodiesel based on vegetable or animal fats (oils), as well as products of their esterification (materials from Wikipedia. Found on the Internet <https://ru.wikipedia.org/wiki/Biodiesel>) .

A known method of producing biodiesel by transesterification of triglycerides of vegetable or animal origin (hereinafter raw materials) with alcohol under supercritical conditions in a continuous reactor with a stoichiometric excess of alcohol (see Rodney J. Gleason, Albert S. Worrell, application US 2008/0221344 A1).

The specified method is carried out using a device consisting of tanks for alcohol and raw materials, pumps and a reactor.

The disadvantages of this method and device when using it for the production of biodiesel are the presence of a large list of energy-intensive equipment and the impossibility of practical implementation of the process of separating biodiesel from glycerol and excess methanol.

The closest technical solution is the installation for the continuous production of biodiesel (Gabitov F.R., Gazizov R.A., Gumerov F.M., Usmanov R.A., Yakushev I.A., Yarullin R.S., Pat. RF PM No. 71117), which contains a continuous type reactor, tanks for alcohol and raw materials, high pressure pumps, a vacuum pump, a refrigerator and a delay vessel.

In this device, the method is carried out by supplying alcohol and raw materials to the reactor, feeding the reaction products into a retention vessel and aspirating the alcohol vapor.

The disadvantages of this method and device when using it for the production of biodiesel are: the lack of a preheating line, the reaction product is cleaned of excess methanol in two stages (complex plant design), the separation of the reaction product occurs due to the natural long process of separation of biodiesel and glycerol, complex construction of the holding vessel combined with the reservoir for raw materials.

The objective of the invention is to simplify the technological scheme for producing biodiesel, reducing energy consumption in the process, reducing the duration of the process for producing biodiesel.

The solution to the technical problem is achieved by the fact that the claimed device for the continuous production of biodiesel fuel containing a continuous reactor, tanks for alcohol and raw materials, high pressure pumps, a vacuum pump, a refrigerator and a delay vessel, is additionally equipped with a heat exchanger located inside the tank for raw materials, gravity a dynamic separator connected to the delay vessel, pressure regulators located in the alcohol container and in the delay vessel, as well as a pre-line Yelnia warm connecting the reactor outlet to a pressure regulator disposed in the tank for alcohol, wherein the vacuum pump and a refrigerator arranged in a line and connected in series.

The objective is achieved in that in a method for producing biodiesel fuel, which includes supplying alcohol and raw materials to the reactor, supplying reaction products to a retention vessel, condensing and aspirating alcohol vapors, the reactor is preheated, while the alcohol is supplied to the reactor at a pressure of P = (1 ÷ 8) P _cr and a temperature T = (1 ÷ 1,8) T _cr, raw heat exchanger is carried out by the heat of the reaction product, condensation of the vapor and alcohol extraction is performed simultaneously, and the process of separating the reaction product is carried gravitationally into the dynamic separator.

The drawing shows a diagram of a device for producing biodiesel containing a tank for alcohol 1; continuous type 2 reactor; reservoir for raw materials 3; retaining vessel 4; refrigerator 5; gravitational-dynamic separator 6; vacuum pump 7; high pressure pump 8, 9; pressure regulator 10, 11; heat exchanger 12; preheating line 13.

The method is as follows.

The preparatory work includes the preliminary heating of the reactor, namely:

- open the shutoff valves between the alcohol tank 1, the high pressure pump 8 and the continuous type 2 reactor, turn on the high pressure pump 8 and pump the alcohol through the continuous type 2 reactor at a pressure of P = (0.5 ÷ 1) P _cr .

- at the same time voltage is applied to the magnesia cable of the reactor to heat the alcohol to a working temperature T = (1 ÷ 1.8) T _cr .

Then open the shutoff valves between the raw material tank 3, the high pressure pump 9 and the continuous type reactor 2. Turn on the high pressure pump 9, feed the raw materials to the continuous type reactor 2. At the same time, the shutoff valves between the continuous type reactor 2 and the stop vessel 4 are opened, and also between the holding vessel 4, the refrigerator 5, the vacuum pump 7 and the tank for alcohol 1.

The resulting product of the reaction of transesterification of raw materials in a medium of supercritical alcohol begins to flow into the retaining vessel 4.

Excess alcohol is sucked out of the latter by a vacuum pump 7, which is in a vapor state, which, concurrently condensing in the refrigerator 5, begins to enter the alcohol storage tank 1.

In the retaining vessel 4, an accumulation of the reaction product — glycerol and biodiesel — occurs. Upon reaching a predetermined level, open valves between the retaining vessel 4 and the gravity separator 6.

The presence of a reactor pre-heating line, a heat exchanger for heating raw materials allows more efficient use of thermal energy of various flows, reduces energy consumption in the process; the location of the vacuum pump in line with the refrigerator simplifies the technological scheme for producing biodiesel; gravitational-dynamic separator operates without any additional energy costs, because the rate of separation of the product in it depends on the flow rate of the product itself entering the retention vessel, thereby reducing the duration of the biodiesel production process.

Claims (2)

1. A device for the continuous production of biodiesel fuel containing a continuous reactor, tanks for alcohol and raw materials, high pressure pumps, a vacuum pump, a refrigerator and a delay vessel, characterized in that the device is additionally equipped with a heat exchanger located inside the raw material tank, gravitationally dynamic a separator connected to the delay vessel, pressure regulators located in the alcohol container and in the delay vessel, as well as a preheating line, connect the output of the reactor with a pressure regulator located in the tank for alcohol, while the vacuum pump and the refrigerator are located on the same line and are connected in series. 2. A method for continuously producing biodiesel on a device according to claim 1, comprising supplying alcohol and raw materials to the reactor, supplying reaction products to a retention vessel, condensing in a refrigerator, and aspirating alcohol vapor with a vacuum pump, characterized in that the reactor is preheated, wherein feeding an alcohol to the reactor are at a pressure P = (1 ÷ 8) P and temperature T _cr = (1 ÷ 1,8) T _cr, raw heat exchanger is carried out by the heat of the reaction product, condensation of the vapor and alcohol extraction is carried od TERM, and the process of separation of the reaction product is carried out in the gravity-dynamic separator.