A method of producing hydrocarbon mixtures rich in aromatics from naphtha feedstock (100 or 100a) comprising the steps of: i. feeding naphtha feedstock (100 or 100a) and liquified petroleum gases, LPG (101a and 101b) into reactor effluent/feed heat exchanger (200 or 300) to yield a mixture (102 or 102a), wherein the naphtha feedstock (100 or 100a) and the LPG (101a and 101b) have an initial temperature of below 100°C prior to the step (i) and wherein the mixture (102 or 102a) achieves a temperature in the range between 350°C to 500°C in the reactor effluent/feed heat exchanger (200 or 300); ii. channeling the mixture (102 or 102a) obtained from the step (i) into at least one reactor via integrated heater to produce hydrocarbon mixtures rich in aromatics, wherein the heater raises the temperature of the mixture (102 or 102a) to at most 550°C; iii. channeling effluent obtained from the step (ii) into the reactor effluent/feed heat exchanger (200 or 300) for reducing its temperature to below 100°C before it is transferred to a cooling tank, wherein the temperature of the effluent is reduced by transferring the heat to the incoming mixture (102 or 102a); iv. cooling the effluent obtained from the reactor effluent/feed heat exchanger (200 or 300) in the step (iii) in the cooling tank to a temperature below 40°C; v. introducing cooled effluent obtained from the step (iv) into first stage separator to obtain light gases, wherein the separation is carried out at a temperature below 40°C and at a pressure ranging between 5 to 30 bars; vi. transferring the remaining liquid obtained from the first stage separator in the step (v) into second stage separator and separating the remaining liquid in the second stage separator to yield LPG, wherein the separation is carried out at temperatures and pressures above the temperatures and the pressures in the first stage separator; and vii. directing the effluent obtained from the second stage separator in the step (vi) into stabilizer to separate off gas, LPG and reformate, wherein the reformate is the hydrocarbon mixtures rich in aromatics, wherein the mixture (102 or 102a) achieves a temperature in the range between 350°C to 500°C in the reactor effluent/feed heat exchanger (200 or 300) in the step (i) by way of heat exchange from the effluents obtained from step (ii) to the mixture (102 or 102a) in the reactor effluent/feed heat exchanger (200 or 300), wherein the heater generate waste heat that is recycled into air preheater to raise the temperature of air from around 30°C to at least 100°C by way of heat exchange from the waste heat to the incoming air that eventually used along with fuel as heating source to run the heaters and wherein the LPG is recycled back into the reactor effluent/feed heat exchanger (200 or 300) without using a compressor. i. feeding naphtha feedstock (100 or 100a) and liquified petroleum gases, LPG (101a and 101b) into reactor effluent/feed heat exchanger (200 or 300) to yield a mixture (102 or 102a), wherein the naphtha feedstock (100 or 100a) and the LPG (101a and 101b) have an initial temperature of below 100°C prior to the step (i) and wherein the mixture (102 or 102a) achieves a temperature in the range between 350°C to 500°C in the reactor effluent/feed heat exchanger (200 or 300); ii. channeling the mixture (102 or 102a) obtained from the step (i) into at least one reactor via integrated heater to produce hydrocarbon mixtures rich in aromatics, wherein the heater raises the temperature of the mixture (102 or 102a) to at most 550°C; iii. channeling effluent obtained from the step (ii) into the reactor effluent/feed heat exchanger (200 or 300) for reducing its temperature to below 100°C before it is transferred to a cooling tank, wherein the temperature of the effluent is reduced by transferring the heat to the incoming mixture (102 or 102a); iv. cooling the effluent obtained from the reactor effluent/feed heat exchanger (200 or 300) in the step (iii) in the cooling tank to a temperature below 40°C; v. introducing cooled effluent obtained from the step (iv) into first stage separator to obtain light gases, wherein the separation is carried out at a temperature below 40°C and at a pressure ranging between 5 to 30 bars; vi. transferring the remaining liquid obtained from the first stage separator in the step (v) into second stage separator and separating the remaining liquid in the second stage separator to yield LPG, wherein the separation is carried out at temperatures and pressures above the temperatures and the pressures in the first stage separator; and vii. directing the effluent obtained from the second stage separator in the step (vi) into stabilizer to separate off gas, LPG and reformate, wherein the reformate is the hydrocarbon mixtures rich in aromatics,