Diploma in Heat Supply

Contents

Contents

Summary

Introduction

Heat supply

1. Transfer of heat supply system from Belinsky and Likard boiler houses to centralized heat supply from TSEPRUSS CHPP

1.1. Collection and refinement of heat loads

1.2. Heat consumption schedules

1.3. Calculation and construction of heat release control schedules

1.4. Determination of design coolant flow rates

1.5. Hydraulic calculation of heat network pipelines

1.6. Development of hydraulic modes

1.7. Calculation and selection of equipment for the reconstructed area

2. Calculation of CTP equipment

2.1. Thermal and hydraulic calculation of plate water heaters

2.2. Selection of pumps

2. Automation

3. Automation of thermal and hydraulic mode of CTP

3.1. Automation Goals and Objectives

3.2. Principles of operation of local automation circuits

3.3. Automation Devices and Tools

3. Construction and installation works

4. Arrangement of CIW during installation of heating lines

4.1. Composition of works at Krasnoselskaya 67B and Glazunova sites

4.2. Calculation of volumes of work at Krasnoselskaya 67B and Glazunova sites

4.3. Selection of equipment for construction and installation works

4.4. Main Work Solutions

4.5 Quality control of works performance

4. Construction economy

5. Local estimate and calculation of annual operating costs

5.1 Local cost estimate for construction of heating network in sections

Krasnoselskaya 67 B and Glazunova

5.2 Calculation of annual operating costs

5.3. Main directions for saving energy resources in the heat supply system

5. Safety of life

6. Ensuring Safety Requirements When Laying Heat Trays

6.1. Analysis of hazardous and harmful factors

6.2. Technical and organizational measures to ensure safety requirements for laying and operation of heating lines of the urban area

6.3. Emergency protection activities

Conclusion

List of sources used

Applications

Appendix A - Design Heat Flows and Coolant Flow Rates

Appendix B - Network water temperature control schedules

Appendix B - Hydraulic Heating System Calculation

Appendix D - Calculation of labor costs for heating system

Appendix E - Local Cost Estimate

1.1. Collection and refinement of heat loads

The estimated heat consumption for heating and hot water supply for RTS "TSEPRUSS" subscribers is accepted according to MUP < < Kaliningradteploset > > and is presented in Table A.1 of Appendix A. Total heating load Qo = 7.87 Gcal/h (9.13 MW), hot water supply (maximum) Qhmax = 5.81 Gcal/h. 6.74 The total load was Q = 13.68 Gcal/h (15.87 MW).

The estimated heat consumption for the subscribers of the Belinsky, Likard boiler houses connected to the TSEPRUSS boiler room is taken according to the MUP < < Kaliningradteploset > > and is presented in Table A.2 of Appendix A. Total heating load Qo = 1.081 Gcal/h (0.254 MW), hot water supply (801 MHh Qh) The total load was Q = 1.782 Gcal/h (2.067 MW).

Heat consumption schedules

Heat consumption schedules are necessary to solve a number of issues of district heat supply: selecting heat source equipment, choosing the mode of loading and repair of this equipment, etc.

Seasonal schedules of heat consumption for heating, ventilation and hot water supply are a graphical dependence of the hourly heat consumption on the outside air temperature. For heating and ventilation systems, this relationship is linear and can be shown as straight inclined lines. Heat consumption for hot water supply does not depend on ambient temperature and is considered constant.

1.2.1. Create an annual schedule by day

Results of calculations according to formulas (1.1-1.2) are summarized in Table 1.1.

Table 1.1 - Data for seasonal plots of heat consumption depending on ambient air temperature

The plot is shown in Fig. 1.1.

Table 1.2 [3] is drawn up to plot heat consumption depending on the duration of external temperatures.

1.2.2. Create an annual schedule by month

Average monthly outdoor air temperatures are required to schedule annual body consumption by month

Calculation of average monthly heat consumption is made according to formulas

Calculation and construction of heat release control schedules

Since this project provides for simultaneous heat supply through two-pipe water heating networks to heating, and hot water supply, central qualitative control of heat release by the total heating and hot water supply load (increased temperature schedule) is used.

We calculate and create an increased schedule when the system is closed.

With closed heat supply systems, the selection of the hot water heaters connection scheme should be made based on the value of the ratio of the maximum hourly heat flow to hot water Qhmax and to heating Qo, adopted in heat networks for controlling heat release, as well as the accepted means for regulating water or heat flow (Qhmax/Qo).

In order to maintain the heat balance, the average daily water temperatures in the supply line of the network must be taken higher than the heating schedule. The value of this excess is determined by the water temperature in the return pipeline of the heating system and the following factor:

With this value of the coefficient, central qualitative control of the heating load is taken.

Given different values and ambient temperatures tn (usually tn = + 8; 0; - 10; tv; to) is determined to be t1.0; τ2,0 ; t3.0 and build a heating schedule of water temperatures (Appendix B). To satisfy the hot water supply load, the water temperature in the supply line t1.0 cannot be lower than 60 ° C in open heat supply systems, and 70 ° C in closed heat supply systems. To do this, the heating schedule is straightened at the specified temperatures and becomes heating and household.

To determine the temperature difference of the coolant of the local heat consumption system, use the formula:

To determine the calculated difference of coolant temperatures in the return pipelines of the local heat consumption system and the thermal network, the following formula is applied:

Determination of design coolant flow rates

Design flow rate of network water for determination of pipe diameters in water heat networks with qualitative control of heat release should be determined separately for heating and hot water supply using the formulas:

a) for heating

where: Qo - design heating load, Gcal/h; Cp - heat capacity of coolant (for water is taken equal to - 4.19 kj/kg); t1, t2, respectively, of direct and reverse water temperature, С (temperature plot - 95/70).

b) for hot water supply in closed heat supply systems:

- medium, at two-stage schemes of water heaters connection

where: Qhm design load for hot water supply system, Gcal/h; th hot water temperature in WAN system (60 0С); tc source water temperature (5 0С).

- maximum, with two-stage water heater connection diagrams

Total design flow rates of network water, kg/h, in two-tube heat networks in open and closed heat supply systems with qualitative control of heat release should be determined by the formula

The factor K3, which takes into account the share of the average water flow rate for hot water supply during heating load control, is taken in the amount of 1.2 for a closed heat supply system with a total load of less than 100 MW.

Results of calculations according to formulas (1.6-1.9) are given in Appendix B.

Hydraulic calculation of heat network pipelines

The main task of hydraulic calculation is to determine the diameters of pipelines, as well as pressure losses in sections of heat networks. Based on the results of hydraulic calculations, hydraulic modes of heat supply systems are developed, network and make-up pumps, automatic controllers, throttling devices, equipment of heat stations are selected.

The hydraulic calculation begins with the design diagram of the main line and the nearest branch.

Based on the design scheme, hydraulic calculation is carried out, taking the recommended specific pressure losses for the main line (R0) 50 Pa/m, and for the branch up to 300 Pa/m.

The pipe diameters of the heating network sections are selected depending on the calculated water flow rate and specific pressure losses according to the table compiled for the pipes with the coefficient of equivalent roughness K E = 0.5 mm and the calculated design diameter of the pipeline.

Hydraulic calculation is performed according to Tables [6] and is given in Appendix B.

Losses of heating system pressure from RTS "CEPRUSS" to house number 33 on the street. Radists amounted to 21.4 m. Art. (With a located head on the tie-in 47 m. Art.). The total length of the heating network was 6279 m .

Heat network pressure loss from cat. Likard to house number 25 on the street. Dobrolyubov amounted to 0.65 m. Art. (With a located head of 30 m. Century.). The total length of the heating network was 173 m.

Heat network pressure loss from cat. Belinsky to the house number 67 B on the street. Krasnoselskaya amounted to 1.16 m. Art. (With a located head of 30 m. Art.). The total length of the heating network was 337 m.

Pressure losses on the reconstructed section of the heating network (Glazunova St. 9A11) when replacing pipeline diameters with dn = 159 mm amounted to 0.31 m.

Pressure losses on the reconstructed section of the heating network (Krasnoselskaya St. No. 67 B) when replacing the diameters of pipelines with dn = 114 mm amounted to 0.83 m. Art.

Development of hydraulic modes

Piezometric graphs are widely used to study pressure conditions in heat networks and local building systems.

When connected to an existing thermal network, the initial data for piezometric graphs are:

differential pressure at the connection point;

head losses in the area under consideration (according to hydraulic calculation);

For the piezometer of the heating network from CTP to house number 33 on the street. Radistov:

P1 = 54.8 m, P2 = 27.4 m, the general losses of a pressure according to hydraulic calculation ΔР = 22.4 m.

Build Sequence:

Longitudinal profile of heating line is applied with corresponding horizontal and vertical scale (Mg 1:2000, Mv 1:200).

The absolute elevations of the alignment are placed

Pressure drops in connection points are applied

According to the hydraulic calculation, pressure loss lines in the return and supply pipelines are applied

Static pressure line shall be applied (static pressure shall not exceed 60 m - for systems with cast iron heating devices; must exceed the highest consumer by 5 m - from the conditions of filling the system; must be at the highest point of the route at least 15 m - from the conditions of non-boiling water in the supply pipeline).

When analyzing the constructed piezometric graphs, it was found that the located head at the end of the route is 5 m. Such a head is sufficient for the normal operation of the TTC.

Calculation and selection of equipment for the reconstructed area

Initial data for thermal calculations are coolant temperature, thermophysical characteristics of layers of thermal insulation structure, soil and channel during underground laying, ambient temperature (soil, air).

1.7.1. Calculates the thermal insulation thickness for the cat to be reconstructed. Likard

As per normalized density of heat flow, thickness of heat insulation from bitumoperlite for two heat conductors d = 0.159 m is determined with no-channel gasket. Laying conditions and calculation data we accept :

Average annual temperature of the heat carrier τср1=72 °C, τср2=55 °C. Depth of laying of heat conductors axis h = 1 m. Soils - low-moisture loam p = 2000 kg/m3 average annual soil temperature at depth of laying t0 = 5 ° С.

Rated heat flux density is: q1/norm = 69 W/m and q2/norm = 52 W/m

Accepting coefficient of heat conductivity of the bitumoperlit λ/из = 0.11 W / (m · OS) taking into account coefficient of moistening K =1.1

We determine the efficiency of thermal insulation from bitumoperlite for a two-tube thermal network of a channel-free gasket.

We accept the thickness of the main insulation layer δfrom = 0.18 m (in 2 layers), then the outer diameter of the insulation layer dfrom = 0.519 m, and with the cover layer δp.s. = 0.006 m, the diameter of the pipeline with the insulation structure is dp.s. = 0.531 m.

We determine the thermal resistance of the insulation layer:

Thermal resistance of each heat line is expressed by the formula:

Find a thermal resistance that takes into account the mutual influence of thermal flows of thermal conductors, we find according to the formula:

We determine specific heat losses by supply and return heat lines, having previously received differences in temperatures of network water and soil for supply and return pipelines equal to:

Total specific heat losses by both heat conductors:

Then we calculate heat losses by pipelines in the absence of thermal insulation. Thermal resistance of soil at non-insulated thermal conductors:

The thermal resistance of each heat line in the absence of insulation will be equal to the thermal resistance of the soil,

1.7.2. Calculates the thermal insulation thickness for the cat to be reconstructed. Belinsky

As per normalized density of heat flow, thickness of heat insulation from bitumoperlite for two heat conductors d = 0.108 m is determined with no-channel gasket. Laying conditions and calculation data we accept :

Average annual temperature of the heat carrier τср1=72 °C, τср2=55 °C. Depth of laying of heat conductors axis h = 1 m. Soils - low-moisture loam p = 2000 kg/m3 average annual soil temperature at depth of laying t0 = 5 ° С.

The rated heat flux density based on is:

q1/norm = 55 W/m and q2/norm = 42 W/m

Accepting on coefficient of heat conductivity of the bitumoperlit λ/из = 0.11 W / (m · OS) taking into account coefficient of moistening K =1.1

αfrom = γ/from· K = 0, 11· 1.1 = 0.12 W/( m· ° С)

We find the thermal resistance of the supply and return heat conductors according to the formula (1.21):

We determine the efficiency of thermal insulation from bitumoperlite for a two-tube thermal network of a channel-free gasket.

We accept the thickness of the main insulation layer δfrom = 0.16 m (in 2 layers), then the outer diameter of the insulation layer dfrom = 0.428 m, and with the cover layer δp.s. = 0.006 m, the diameter of the pipeline with the insulation structure is dp.s. = 0.440 m.

Find a thermal resistance that takes into account the mutual influence of thermal flows of thermal conductors, we find according to the formula (1.30):

(m· 0С )/W

We determine specific heat losses by supply and return heat pipelines (1.31, 1.32), having previously received differences in temperatures of network water and soil for supply and return pipelines equal to:

Total specific heat losses by both heat conductors (1.33):

Then we calculate heat losses by pipelines in the absence of thermal insulation. Thermal resistance of soil at non-insulated heat conductors (1.34):

The thermal resistance of each heat pipe in the absence of insulation will be equal to the thermal resistance of the soil, i.e.:

R1nose = R2nose = Rgr = 0.991 (m· 0С )/W

Specific heat loss of non-insulated supply and return heat lines

The total heat loss will be:

Thermal insulation efficiency is calculated by formula (1.35):

Thermal and hydraulic calculation of plate water heaters

When calculating and selecting CTP equipment, it is necessary to take into account the thermal and hydraulic mode of the connected systems.

Considering the lower capital and operating costs, a closed scheme with dependent connection of the heating load was adopted for consideration (Fig.2.1). Preparation of water for hot water supply needs is performed in a two-stage heat exchanger. Heat carrier preparation for heating system is performed by means of mixing valve 14 and mixing pump 8. Reduction of coolant pressure to permissible in local systems is performed by valve 4.

To pump coolant through hot water heat exchangers and heating system, it is necessary to install a circulation pump on the return line. Calculation and selection of CTP equipment is given below.

The scheme of connection of hot water heaters in closed heat supply systems is selected depending on the ratio of maximum heat flow to hot water supply and maximum heat flow to heating

With this ratio, a two-stage scheme for connecting hot water heaters is used.

Calculation of plate water heaters of hot water supply is performed according to the procedure given in [18].

Selection of pumps

To ensure the hydraulic mode in accordance with the piezometric schedule of the thermal network, it is necessary to select pumping (boosting), circulation and mixing pumps.

When selecting pumping pumps to be installed on the return pipeline in accordance with paragraph 3.5 [18], take:

pump supply - by the calculated water flow rate at the inlet to the heat station,

head - depending on the design pressure in the heat network and the required pressure in the connected heat consumption systems.

According to the flow rate G = 202 m3/h and the required head H = 60 m, the SE16070 grade pump in the amount of three pieces (one standby) is selected.

When selecting the mixing pumps for the heating system to be installed in accordance with paragraph 3.5. [18] on the bridge between the supply and return piping, the following shall be accepted:

head - 2-3 meters more than losses in the heating system;

Composition of works at Krasnoselskaya 67B and Glazunova 11 sites

1. Fencing arrangement:

- part tray at a distance of up to 30 m;

- installation of racks with preparation of the base and their fixing on the base with pins;

- suspension of shields with bolting (for shields with a height of 2.2 m).

2. Excavator trench development:

- cutting of vegetal soil by bulldozer;

- installation of excavator in the face;

- soil development with ladle cleaning;

- excavator movement during operation;

- cleaning of soil loading sites;

3. Arrangement of pits in places of welding of non-rotating joints.

4. Refinement of trench bottom:

- manual loosening of soil;

- soil ejection on trench brow;

- cleaning of bottom surface and walls.

5. Sand base arrangement:

- layout of trench bottom by sighting;

- installation of side boards and lighthouses;

- supply of materials to the trench;

- leveling and compaction of materials with inspection by sighting;

6. Assembly of pipes into links with welding on trench edge:

- laying of beds;

- laying of pipes on beds;

- cleaning and adjustment of edges;

- centering and maintenance of pipes in case of joints tacking;

- turning of links at welding of joints.

7. Laying of pipeline links with non-rotating joint welding:

- slinging and lowering of pipe links into the trench;

- laying of pipe links on the base;

- assembly of pipe links;

- fixation of pipes in trench.

8. Installation of gate valves (in Krasnoselskaya 67B section):

- slinging and lowering into the trench;

- installation on the finished base;

- centering and adjustment.

9. Shining of joints.

10. Insulation of heat pipeline joints.

11. Backfilling of trench:

- actuation of the unit;

- soil movement with trench backfilling;

- return empty.

12. Trench backfilling soil compaction:

- trailer and rink uncoupling;

- soil compaction by rollers;

- rink turns and transitions to adjacent platform.

13. Final tests:

- cleaning of pipelines;

- installation of blankings and pressure gauge;

- connection of compressor or air bottle to the pipeline;

- filling the pipeline with air up to the specified pressure;

- preparation and washing of soap solution;

- elimination of defects;

- disconnection and removal of blankings.

14. Disassembling the fence.

Calculation of work volumes at Krasnoselskaya 67B and Glazunova 11

Selection of equipment for construction and installation works

The set of machines for earthworks includes excavators, dump trucks and bulldozers. This set of machines performs work on the passage of the trench, removal of excess soil, backfilling after completion of installation work in it.

For the development of trenches and pits, single-bucket excavators with a capacity of 0.15-1.0 m3, equipped with a reverse shovel or dragline, are most often used.

When determining the required parameters of excavators, it is necessary to build a cross section of the trench in the most buried place (Fig. 4.1).

The required unloading radius of the excavator is caused by the need for a dump device of certain sizes. The most preferred movement pattern of the excavator is the movement of the excavator along the trench axis.

For installation of parts and structures of heat and gas supply systems boom self-propelled cranes on automobile, pneumatic and caterpillar runs are used.

The choice of the type of crane is influenced by soil conditions, the dimensions of the cross section of the trench and the mass of the mounted elements. At that required departure of crane hook during installation of prefabricated elements of heat networks

The bulldozer is selected based on the average distance of soil movement from the dump to the trench. Approximately it can be taken equal to the distance between the axes of the trench and dump. I'm picking up bulldozer D39, with a travel distance of up to 5 m.

Bulldozer specifications:

• dump type: non-rotating

• dump length: 2.56 m

• dump height: 0.8 m

• power: 75 hp

control: hydraulic

Main Work Solutions

4.4.1. Method of works execution

1. The in-line method is used to perform the work in this diploma project. In the flow method, homogeneous processes are performed sequentially, and heterogeneous processes are performed in parallel. This method is characterized by a minimum resource consumption and a short duration of installation work.

2. Electric power is necessary for lighting, as some work is carried out on the second shift

3. Water is required for site employees and for hydraulic testing of the heating network

4. Site oxygen required for metal cutting

5. Number of appliances for the needs of workers - 4 pcs. (one room for 10 workers).

6. For construction and installation work, storage space for materials (pipes, etc.) is required. Number of storage locations:

Pipe storage area (Krasnoselskaya 67B section):

I accept that the number of pipes laid near the brow of the trench is 7 m, and the length of one pipe is 10 m, 6 pieces. Therefore: Lt./60m = l [pcs].

where Lt. - total length of all pipes brought to the construction site

l - number of pipe storage places

364/60 = piece.

Therefore, at the construction site (Krasnoselskaya 67B section) you need 6 places for pipes.

Pipe storage area (Glazunov section 11):

I accept that the number of pipes laid near the brow of the trench is 7 m, and the length of one pipe is 10 m, 6 pieces. Therefore: Lt./60m = l [pcs].

where Lt. - total length of all pipes brought to the construction site

l - number of pipe storage places

400/60 = piece.

Therefore, at the construction site (Glazunov section 11) you need 7 places for pipes.

4.4.2. Determination of labour intensity of construction and installation operations

The calculation of labor intensity of manual and mechanized construction and installation processes, as well as machine time costs, is carried out according to YeniR .

Labor intensity of work in human days. It is determined by the formula:

(4.18)

where is Hvr. - time norm per unit of work, human hour;

V - work volume in units of measure (it is accepted on ENiR);

8 - working shift duration, h.

Calculation results are given in Appendix G.

According to certain labor intensity, a work schedule is drawn up, which is given in the graphic part.

Quality control of works execution

Acceptance of heat networks completed by construction is performed in accordance with SNiP III376 and 1113074. The newly built pipelines are put into operation by a commission consisting of representatives of the customer, contractor and the Department of Heating Networks (Technical Supervision), and with direct water collection and a representative of the sanitary and epidemiological service. Hot water pipelines (t > 115 ° C) are put into operation in accordance with SNiP III3074. Pipelines with a working pressure of 0.07 - 1.6 MPa (0.7 - 16 kgf/cm2) and a temperature of more than 115 ° C are put into operation taking into account the "Rules for the arrangement and safety of operation of steam and hot water pipelines" without registering heat pipelines in the bodies of the State Gortekhnadzor .

The commissioning of the completed construction of the entire facility or its part (which can be independently operated) is preceded by the intermediate acceptance of individual parts or types of work during construction. Intermediate acceptance, drawn up by the relevant acts, is subject to: breakdown of the route, arrangement of the bases of trenches and pits; laying of pipelines; welding of pipelines and embedded parts of prefabricated structures, corrosion protection coating of pipes; installation of building structures; termination and monolaying of joints, thermal insulation of pipelines and drain devices; waterproofing of building structures; electric protection device; stretching of U-shaped compensators; revision and testing of valves; gland compensators; backfilling of trenches and pits; cleaning of the inner surface of the cores, laying of the cases; flushing of pipelines; hydraulic or pneumatic test.

Composition of covert works acts:

check of pipe slope

check of inner surface of pipes (determined by shining)

outer surface of pipes (quality of cleaning)

anticorrosive coating (material)

thermal insulation (material, thickness, crust)

gasket construction (drawing No.)

Commissioning of heat pipelines is carried out by working commissions (from the customer).

Fundamentals of construction products pricing in the market environment

The mechanism for generating prices for construction products is based on regulatory methods. The estimated cost of construction products on the territory of the Russian Federation is determined on the basis of MDS 8135.2004.

Estimated cost of construction and installation works (CIW) amount of funds for construction in accordance with the design model.

The estimated cost is the basis for determining the size of capital investments, financing construction, the formation of contractual prices for construction products, settlements for contracted works.

As part of the diploma project, a local estimate was made for the reconstruction of sections of the thermal network.

The local estimate is based on the estimate base put in place since 1.01.1984.

Basic index method is used to determine estimated cost of construction and construction works in 2009 prices. Calculated indices by type of works to the base of 1984 as of 1.04.2001 (Data of RegioStroyInform).

According to the local estimate, all costs related to the execution of the construction and construction works are determined, which include direct costs, overhead costs and estimated profit. When developing local estimates, open and closed rates were taken into account for ERER collections. At open rates, material resources for SNiP IV484 and price list 0608 (wholesale prices for reinforced concrete and concrete products and structures) were additionally taken into account.

Recommended rates of overhead and estimated profit have been adopted for calculation. The estimated calculation is based on the initial data.

On the basis of the estimated calculation, the contract price is formed as part of the estimated documentation. The contract price accepted by the customer and the contractor may be revised by agreement of the parties. At the end of the contract price, the VAT amount is shown as a separate line.

Local estimate for the reconstruction of the quarterly heating line

The local cost estimate is based on the following input data:

The name of the object is Khabarovsk heat networks (Pobeda, Rudneva St. No. 3345)

Territorial Construction Area - X (HEREP84, Annex 2)

District wage ratio - 1.3 (EREP84, annex 8)

CIW overhead - 25.8% (according to established standards)

Estimated profit - 8% (according to established standards)

Conversion factor from overheads to labor costs - 0.0092

Share of wages in overhead expenses - 0.18

Conversion factor from driver's salary to labor costs - 1.29

Transition index from 1984 to 2001 prices - 26.5

The scope of work is adopted in accordance with design solutions according to process diagrams. Local estimate for the reconstruction of the quarterly heating line is given in Appendix D. Contract prices for the reconstruction of the quarterly heating line are given in Table 5.1.

Table 5.1 - List of contract prices

Customer (General Contractor) ____________________________

General Contractor (subcontractor) ________________________

Based on local estimate and attached to contract (subcontract)

Calculation of annual operating costs

General provisions for calculation of annual operating costs

In its activity, the company is guided by the principles of economic calculation, which is based on self-reliance. The main indicator of the enterprise's work is the cost of thermal energy. Cost reduction can be achieved by application of the most relevant technologies in construction, operation, reduction of heat losses, application of automated control systems, training of qualified personnel.

Annual operating costs are an important cost item.

During operation of the heat network, during its operation

Calculation and estimate of annual operating costs

Initial data for calculation of annual operating costs

annual heat energy consumption of the heat supply system Q = 119836.8 Gcall/year

thermal energy tariff T = 714 rub/Gcall + 18% VAT = 842.52 rub/Gcall

estimated cost of construction and installation works for heat supply system - 259,212 thousand rubles

depreciation rate as a percentage (%) of the estimated cost of construction and construction - 4%

overhaul costs as a percentage (%) of the estimated cost of construction and construction - 2%

maintenance costs as a percentage (%) of the estimated cost of construction and construction - 1.2%

number of maintenance personnel - 2 fitters of III category

official salary - 2100 rubles.

salary bonus - 20%

unified social tax - 26%

contribution rate for management, occupational safety and safety - 30%

The cost of thermal energy is:

→

The main technical and economic indicators of the project are summarized in Table 5.3.

Table No. 5.3 - Main technical and economic indicators of the project

Description of indicators

Units of measurement

Quantity

Main directions for saving energy resources in the heat supply system

Heating networks are very expensive structures, and significant funds are spent on their construction and operation. Due to the increased requirements for cleanliness of the air basin of cities and towns, large thermal stations began to be built outside the city limits at a significant distance from the areas of thermal consumption. This necessitates the construction of long transit routes, which in turn requires increased capital expenditures. The smooth and cost-effective operation of district heating systems depends mainly on the quality of the construction of heating networks and on how well their technical operation is carried out.

The main factor in reducing the cost of building heat networks is the use of new efficient structures and materials, progressive construction methods during the complex mechanization of construction and installation works.

The heat saving strategy is based on three main areas: heat accounting, heat audit and heat consumption control.

To do this, you must:

Focus on fuel and energy savings. Switch to independent consumer connection schemes, introduce telemechanics and create ACS of heat supply systems. Use water and thermal energy meters, provide heat supply to the city in optimal economic conditions. Promptly detect and eliminate equipment failures, eliminate leaks in the thermal networks and basements of the building, switch to the installation of hot water meters. The introduction of heat meters allows the heating network to more efficiently organize the heat distribution and consumption process. Summarizing the experience of the heating network with subscribers having instrument accounting of the received heat, for the further successful implementation of heat meters and the implementation of the energy saving program, it is necessary to ensure a set of measures of the organizational, technical and scientific plan. As a result, the consumption of water by consumers is sharply reduced.

The construction of thermal networks must be carried out using modern structures of thermal conductors with insulation from polyurethane foam in a polyethylene shell, this will reduce heat losses by an order of magnitude compared to traditional structures

Analysis of hazardous and harmful factors

"Occupational safety in construction" is an applied technical science that identifies and studies industrial hazards and occupational hazards and develops methods for their prevention or mitigation in order to eliminate industrial accidents and occupational diseases of workers, accidents and fires.

The main objects of the study are the person in the process of labor, the production environment and situation, the relationship of the person with industrial equipment, technological processes, organization of labor and production. Based on the findings of classical and engineering sciences, labor protection develops a system of measures that constantly increase the level of labor safety in construction.

The methodological basis of Labor Protection in Construction is a scientific analysis of working conditions, the technological process of construction production, applied and obtained building materials and structures in terms of the possibility of the occurrence of hazards and hazards during the construction and operation of buildings and structures. Based on such analysis, hazardous areas of production are determined, possible hazardous situations are identified and measures for their prevention and elimination are developed. These issues are considered in dynamics, in development, in order to ensure further progress in labor protection. The basis of discipline in all its sections is a preventive beginning.

Exposures that can cause negative disorders in the well-being and health of people are called hazards.

Danger is a property of elements of the human-habitat system that can cause damage to people, the natural environment and material resources. According to the sources of their occurrence, it is customary to divide all hazards into natural and anthropogenic.

Natural hazards arise from natural phenomena in the biosphere, such as earthquakes, floods, hurricanes, cyclones, avalanches.

A characteristic feature of natural hazards is the surprise of their occurrence, although some of them have learned to predict, for example, earthquakes, hurricanes, tsunamis. Natural hazards are relatively stable in time and strength of exposure. The occurrence of anthropogenic hazards is primarily associated with active man-made activities.

The sources of anthropogenic hazards are people themselves, as well as technical means, buildings and structures, transport highways - everything that is created by man. Damage from anthropogenic hazards is higher, the greater the density and energy level of the technogenic means used. People almost always interact with technical means (means of transport - car, tractor, train; household appliances; gas and electric plates; tools (machine, conveyor, heating furnace), which on the one hand help them in work and life, and on the other, are sources of dangerous effects.

The growing negative impact on workers involved in the construction and maintenance of heating networks, as a rule, is due to inattention, haste, violation of technological recommendations, labor discipline and, most importantly, the lack of necessary knowledge about the causes of hazards, as well as about the consequences arising in hazard zones.

By the nature of human exposure, all hazards differ on harmful and traumatic (traumatic) ones.

Harmful effects (harmful factors) can lead to deterioration of well-being or disease with prolonged exposure to them. These include the effects of toxic substances contained in atmospheric air, water, food products, insufficient illumination, elevated or reduced air temperatures, and a decrease in the oxygen content in the air of the room. Similarly, the effect on humans of increased noise, vibrations, electromagnetic fields, ionizing radiation.

So, work with insufficient lighting leads to faster (1.52 times) fatigue, and in conditions of increased temperatures labor productivity decreases, the body is dehydrated from loss of vitamins and salts, the body's protective reaction decreases, cardiovascular diseases occur.

Traumatic effects (traumatic factors) lead to injuries or death of people during their single action. Injuries include electric current, falling objects, the action of movable elements of various installations and means of transport, falls, depressurization of high-pressure systems, often leading to explosions and fires.

The action of traumatic factors is characterized by surprise and speed.

Acute and chronic poisoning are also considered negative effects on humans. Chronic poisoning is a disease that develops after systematic prolonged exposure to toxic substances at doses much lower than in acute poisoning. Such properties are characterized by lead and manganese compounds, mercury vapors, which are prone to gradual accumulation in the human body. Getting into the body through the respiratory organs, with food and water, lead accumulates in German. When lead concentrations in the blood reach about 0.7 μg/ml, signs of poisoning appear - the body's resistance to infectious diseases decreases, chronic bronchitis and others are often recorded. The permissible lead content is 0.250.3 μg/ml.

Microclimate.

Indoor microclimate is the climate of the indoor environment of the premises, which is determined by the combinations of temperature, humidity and speed of air movement acting on the human body, as well as the temperature of the surrounding surfaces.

The parameters of the production microclimate primarily affect the thermoregulation of the body. Thermoregulation refers primarily to the ability of an organism to adapt to the environment by increasing or decreasing heat formation and heat transfer so as to maintain a certain constancy in the temperature of its body. In most healthy people, the body temperature is - 36.6 C.

Human diseases due to a violation of the thermoregulation mechanism can occur in the form of hyperthermia (overheating of the body) or convulsive disease. With a mild form of hyperthermia, drowsiness, nausea, thirst, sweating, dizziness appear, and with severe, up to loss of consciousness.

Under the influence of increased air temperature in combination with increased humidity, the risk of exposure to a number of chemicals increases.

Thus, the parameters of the production microclimate have a complex effect on human well-being. In a certain range of temperatures, humidity and air velocity, different combinations of these factors can cause a feeling of comfort or discomfort.

Dust, harmful gases and vapors.

Since there is no production as such, any harmful emissions are excluded. The actual dust content in the room is 1.52 mm3, this value does not exceed the required standards (for this nature of production - 6 mgm).

The room is equipped with a natural plenum ventilation system, air removal is carried out by a deflector installed on the roof of the building, and inflow due to infiltration of fresh air through window and door openings.

Lighting.

Through the visual organs, a person receives up to 80% of the information, the quality of this information depends largely on coverage, unsatisfactory in quantitative terms, it wears the visual organs and the human body as a whole, and can cause accidents.

There is natural, artificial and combined (mixed) lighting.

The natural lighting conditions are determined by the number and area of window openings, the purity of the windows. Artificial lighting conditions are determined by the number of lamps, their power, location in relation to workplaces.

The unit of illumination is luxury (Lc) - surface illumination with an area of ​ ​ 1 m2 with a luminous flux of 1 Lumen.

Various filament lamps and lamps are used for production premises. Incandescent lamps include: vacuum, gas-filled with a mixture of nitrogen and argon, gas-filled bispiral, etc. Gas discharges include luminescent, arc mercury, xenon, etc. Fluorescent lamps are fundamentally different from incandescent lamps in that they use the phenomenon of cold glow.

The required illumination value in the CTP working room is set depending on the nature and accuracy of the works. According to the eight-bit scale, the designed object can be attributed to the average degree of accuracy, where the object of distinction is primarily measuring instruments and the necessary accuracy of perception from 0.5 to 1 mm.

Installed suspended lighting fixtures provide illumination value - 150 Lux (required illumination rate for this room).

Noise and vibration.

Noise - erratic periodic fluctuations of various physical nature. Severe noise causes overload of the hearing aid, hearing fatigue, reduces attention, which can contribute to the occurrence of an accident. Noise affects not only hearing, but also the central nervous system. Noise causes headaches, increased reflex excitability, impaired gastric secretion, increased blood pressure. With prolonged exposure to noise, the functioning of the auditory organs is disrupted and hearing is weakened.

In production, various means are used to reduce noise: this is the isolation of noise in the source by using less noisy elements (for example, replacing sliding bearings with rolling bearings), silencing noise from equipment using local silencers, shielding noise with acoustic screens with sound-insulating ability, using various sound-absorbing materials, using personal protective equipment.

When designing a new or modernizing existing equipment, it is necessary to provide for measures justified by the corresponding calculations to reduce noise to the regulated parameters and permissible values. Normalized noise parameters are standard sound pressure levels.

The source of noise in the CTP room is the pumping unit. Noise level generated at workplaces in rooms by noise sources located in the same rooms

For rooms of this type, at an average geometric frequency of octave bands of 63 Hz, the permissible noise level is 95 dB, [23] it is at 63 Hz that the maximum sound pressure level is observed. Therefore, the noise level does not exceed the permissible limits and does not require additional protection.

The nature of vibration is akin to noise, vibration adversely affects the human body and can cause various diseases.

It is recommended to install equipment on vibration and sound absorbing supports to reduce vibration propagating through building structures. In order to reduce the effect of vibrations, the structural elements of the building should not be connected to the foundations of the machines, powerful electric motors should be installed on separate supports that are not less than 1 m distant from the walls.

For centrifugal pumps with an electric motor, a common foundation plate of sufficiently large sizes is used, various shock absorbers serve as supports for the plate depending on the mass of the electric motor, the rotation speed of its shaft and the natural frequency of soil oscillations.

When calculating shock absorbers, the relationship between the frequency of the disturbance force and the natural frequency of the system is important, usually it is taken equal to more than 4, otherwise the efficiency of vibration isolation is insignificant .

The obtained area of the gasket is the minimum necessary to absorb the oscillations transmitted from the pump and prevent their transfer to building structures and other elements.

Technical and organizational measures to ensure safety requirements for laying and operation of heating lines of the urban area

Protection against moving parts and mechanisms.

The only moving element in the CTP room is a circulation pump, all movable elements are hidden by the pump structure itself, therefore, no special protective equipment and fences are provided.

Protection against heated surfaces.

The heat station is equipped with sectional water-water heaters, for protection from the heated surface, a fence is provided along the entire perimeter of the heat exchanger. Supply pipeline has temperature - 110 0C and is additionally heat insulated. Cylinders from mineral wool with thermal conductivity coefficient -0.076 Wm k are selected as insulation. Insulation layer thickness is selected depending on external diameter of pipeline.

We accept the standard insulation thickness - 50 mm.

Electrical safety.

Electrical safety is a system of organizational and technical measures and means that protect people from harmful and dangerous effects of electric current, electric arc, electromagnetic field and static electricity charges.

In a thermal point, the only element consuming electricity is a circulation pump, not counting artificial lighting.

In order to avoid touching the current-carrying parts, it is necessary to ensure their inaccessibility, in addition, all current-carrying parts must be isolated.

One of the means of preventing electrotraumatism is protective grounding - the deliberate connection to the ground of metal non-conductive parts, which can be energized in the event of a closure to the body of the conductive parts.

The principle of protective grounding is to reduce to a safe value the closure voltages and pitch caused by the closure to the housing. This is achieved by reducing the potential of the grounded equipment (i.e., reducing the grounding resistance), and by equalizing the potential of the base on which a person stands to a potential close to that of the grounded equipment.

Protective grounding is the most common, effective and simple measure of protection against electric shock when closing the housing.

The earthing diagram is as follows:

The pump motor and circuit breaker are connected by means of grounding wires to the common grounding line, the minimum section of which should be at least 48 mm2. Grounding conductors (tubular, angle and rod) are also connected to the same line by welding. Grounding conductors are driven vertically into specially prepared trenches. The trench depth is not less than 0.7 m, the width of the lower base is 0.5 m.

When touching metal current-carrying elements, no shock occurs, since the resistance of the protective ground is hundreds of times less than the resistance of a person. In addition, the protective effect of the grounding is that a person who accidentally touches the current-carrying parts is connected to the electrical circuit in parallel to the grounding, as a result of which the current passing through the human body is sharply reduced.

According to PUE, it is allowed to use natural grounding conductors, various metal structures and equipment that have a reliable connection to the ground, including pipelines, metal elements of buildings and structures that have reliable contact with the ground.

Emergency protection activities

Emergency - a state in which the source of an emergency at a facility or a certain territory violates the normal conditions of life and activity of people, poses a threat to their life, health, etc.

The source of an emergency is understood to mean a dangerous natural phenomenon, an accident, the use of modern means of destruction, etc.

This thermal point serves a residential microdistrict, the number of inhabitants in which is about 1000 people, therefore, in terms of the number of injured people, in case of an emergency, it can be attributed to a regional one. A regional emergency is such an emergency, in which from 50 to 500 people were injured, or the living conditions of from 500 to 1000 people and over 1000 people were violated.

Currently, there are two main areas of minimization of the probability of the occurrence and consequences of emergencies at industrial facilities. The first direction is the development of technical and organizational measures that reduce the risk of realizing the dangerous damaging potential of modern technical means.

Within the framework of this direction, modern technical systems are equipped with protective devices - means of explosion and fire protection of technological equipment, electric and lightning protection, localization and extinguishing of fires, etc.

The second direction is to prepare the facility, service personnel, civil defense services and the population for action in emergency situations.

As part of safety in emergency situations, the CTP is equipped with electro and lightning protection devices, means and auxiliary tools for extinguishing fires and fires.

Training stands are installed in the room, which coordinate the action of working personnel in emergency conditions.

Local estimate for the construction of a heating network in the Krasnoselskaya 67 B and Glazunova 11 sections

The mechanism for generating prices for construction products is based on regulatory methods. The total estimated cost in prices as of the 1st quarter of 2011 is 2425.322 thousand rubles.

The estimated cost is the basis for determining the size of capital investments, financing construction, the formation of contractual prices for construction products, settlements for contracted works. According to the local estimate, all costs related to the construction and installation works are determined, which include direct costs, overhead costs and estimated profit. The estimated documentation was made in accordance with MDS 81352004: the base-index method based on territorial unit rates according to TER2001, TERr-2001. The diploma project used regional indices of recalculation of estimated cost of construction, installation and repair and construction works to the territorial price level for the 1st quarter of 2011, recorded in the estimate base of 2001 .

Recommended rates of overhead and estimated profit have been adopted for calculation. The estimated calculation is based on the initial data. Overhead costs and estimated profit are accrued additionally in accordance with the "Guidelines for determining the amount of overhead costs in construction" (MDS 8133.2004, letter No. UT260/06 dated 31.01.2005) and "Guidelines for determining the amount of estimated profit in construction" (MDS 8125.2001, letter No. AP - 5536/06 dated 18.11.2004) as a percentage of the FOT determined in the current price level. The standards of overhead expenses are adopted for the types of construction and installation works, taking into account K = 0.8 and K = 0.85.

On the basis of the estimated calculation, the contract price is formed as part of the estimated documentation. The contract price accepted by the customer and the contractor may be revised by agreement of the parties. At the end of the contract price, the VAT amount is shown as a separate line.

The scope of work is adopted in accordance with design solutions according to process diagrams. Local budget calculation (local estimate) on construction of a heating system on sites of Krasnoselsky, 67 "B" and Glazunova, 11 is given in appendix D.

Calculation of annual operating costs

6.2.1 General provisions for calculation of annual operating costs

In its activity, the company is guided by the principles of economic calculation, which is based on self-reliance. The main indicator of the enterprise's work is the cost of thermal energy. Cost reduction can be achieved by application of the most relevant technologies in construction, operation, reduction of heat losses, application of automated control systems, training of qualified personnel.

Annual operating costs are an important cost item.

Initial data for calculation of annual operating costs

annual heat energy consumption of the heat supply system Q = 119836.8 Gcall/year

thermal energy tariff T = 714 rubles/Gcall + 18% VAT = 842.52 rubles/Gcall

estimated cost of construction and installation works for the heat supply system - 1328.663 thousand rubles.

depreciation rate in percentage (%) - 4%

Overhaul rates in percentage (%) - 2%

Rate of maintenance costs in percentage (%) - 1.2%

number of maintenance personnel - 2 fitters of III category

official salary - 8000 rubles.

salary bonus - 50%

unified social tax - 34%

contribution rate for management, occupational safety and safety - 30%

The results are summarized in Table 6.1.

Main directions for saving energy resources in the heat supply system

Heating networks are very expensive structures, and significant funds are spent on their construction and operation. Due to the increased requirements for cleanliness of the air basin of cities and towns, large thermal stations began to be built outside the city limits at a significant distance from the areas of thermal consumption. This necessitates the construction of long transit routes, which in turn requires increased capital expenditures. The smooth and cost-effective operation of district heating systems depends mainly on the quality of the construction of heating networks and on how well their technical operation is carried out.

The main factor in reducing the cost of building heat networks is the use of new efficient structures and materials, progressive construction methods during the complex mechanization of construction and installation works.

The heat saving strategy is based on three main areas: heat accounting, heat audit and heat consumption control.

To do this, you must:

Focus on fuel and energy savings. Switch to independent consumer connection schemes, introduce telemechanics and create ACS of heat supply systems. Use water and thermal energy meters, provide heat supply to the city in optimal economic conditions. Promptly detect and eliminate equipment failures, eliminate leaks in the thermal networks and basements of the building, switch to the installation of hot water meters. The introduction of heat meters allows the heating network to more efficiently organize the heat distribution and consumption process. Summarizing the experience of the heating network with subscribers having instrument accounting of the received heat, for the further successful implementation of heat meters and the implementation of the energy saving program, it is necessary to ensure a set of measures of the organizational, technical and scientific plan. As a result, the consumption of water by consumers is sharply reduced.

The construction of thermal networks should be carried out using modern structures of thermal conductors with insulation from polyurethane foam in a polyethylene shell, this will reduce heat losses by an order of magnitude compared to traditional structures.