Study On The Dual-fuel Burning And Heating System For The Boiler On The Hot-oil Paraffin-cleaning Vehicle

With the social and economic fast development, the energy consumeincrease fast. The reserves and output of the rock oil are difficult to meet theenergy demand. So the oil output is in shortage. Now we pursue savingenergy, protecting environment and gaining well economy. It is a trend touse more cleanly energy source --the natural gas.The hot-oil paraffin-cleaning vehicle is designed to be used to clean thewax in the pipeline and out of the pipeline. And it can be used to clear thewax on the cannula wall. It has two functions --cold cleanout and hotcleanout. The hot-oil paraffin-cleaning vehicle nearly all uses the diesel oilas the fuel today. Its configuration is simple and the controlling of it is single.It is operated only by the operator according to his experience and skills tocontrol the optimal ratio between the fuel and the air. But it can't realize. Sothe results are that the fuel can't burn completely and the boiler's heatefficiency is low. And it wastes lots of fuel. Thus the running cost increases.And the boiler gives off lots of black smoke and bad gas to pollute theenvironment. As a result it is urgent to reconstruct the vehicle.The oil field associated gas is a kind of the natural gas. It is the gasassociated with the petroleum. The firedamp is its main component and italso includes the ethane and some other hydrocarbons. Because it hasmuch heavy components its low heat value is higher than the natural gaswhich we call. And the oil field associated gas is a kind of good fuel. Thereare pipelines which convey the oil field associated gas from the gas stationto the oil wells. The cost of the oil field associated gas is very low and it canbe used to be fuel after dealt with. So use it we can decrease thewell-cleaning cost. But the difficult is that the pressure and the flux of the oilfield associated gas are different with various seasons and locations. Sothere are some difficulties in making use of it. To make full use of the oil field associated gas on the well, quicken theoil field's development and decrease the vehicle's running cost, we doresearch on the duel-fuel burning and heating system of the boiler on thehot-oil paraffin-cleaning vehicle. In the study we combined the sensortechnology, the electronic technology, the technology of oil-gasburning-simultaneously and the PLC technology with the burning theory andthe auto-controlling theory and use the study fruit of the dual-fuel automobilefor reference. We built the burning and heating model for the dual-fuelburning and heating system. The dual-fuel system meet the various requirewhich vary with the different temperature and flux of the rock oil medium. Inthe article we research on the burning and heating theory about the dual-fuelburning and heating system of the hot-oil wax-cleaning vehicle boiler.Especially we do some academic work on the optimal ratio between theduel-fuel and the air. Also we design the burning instrument and study thecontrolling system. And we do some alteration on the fuel supply systemand the air supply system. So the dual-fuel burning and heating systemcomes into being. The central content of the work is as being shown below: 1. First we do research on the fuel burning theory and analyze theburning mechanism of the fuels and the flame stabilization theory of the gasfuel. And also we analyze the form mechanism and the condition of thebackfire, the off-fire and the yellow flame and conclude the burningstabilization conditions. We analyze the character of the two fuels (the dieseloil and the oil field associated gas) and the burning theory of the two fuels.We build the burning balanceable equation of the two fuels. And we bringforward the sound model of the ratio between the fuels and the air. Thusthey provide the base for the dual-fuel burning system. 2. Based on the theory analysis some work is done to study thedual-fuel burning and heating system. We make the overall scheme for thedual-fuel system. We do some study on the gas supply system, the diesel oilsupply system and the air supply system. And we select the rational types ofthe valves and the pipelines for the system to meet the system's needs. 3. We study the burning utensil according to the oil-gas burningtechnology and the burning utensil designing theory. The air supply mode ofthe boiler is vertical. We design the burning utensil independently accordingto the designing principle of the fan-burning utensil. The burning utensil canburn the diesel oil, the natural gas or the two fuels synchronously. 4. Using the auto-controlling theory, the electronic technology, thesensor technology and the PLC (Programmable Logic Controller)technology, we study and design the controlling system for the dual-fuelburning and heating system of the vehicle boiler. In the controlling systemwe select the OMRON CPM2A as the controlling center. The controllingsystem can detect the diesel pressure, the gas pressure, the medium intaketemperature, the medium output temperature, the boiler burningtemperature, the air pump rotate speed and the flame signal and so on.Using the testing signals the PLC controlling system can make decisionsand control the diesel oil valve, the gas valve and the air valve to move torealize the rational ratio relationship. 5. In the end, we install and debug the system. We do manyexperiments to test the dual-fuel system. We also do some experiments onthe oil well mouth. In the experiments, we demarcate the sensors and selectthe air excessive coefficient of the diesel oil and the oil field associated gas.We also measure the heat efficiency of the dual-fuel system. Through theexperiments, we prove that the dual-fuel burning and heating system is well,its heat efficiency is higher and it has better economy, better feasibility and...